interim -2010final

CAB 4013

PLA�T DESIG� I

July 2010 Semester

I�TERIM REPORT :

POLYETHYLE�E TEREPHTHALATE (PET) PRODUCTIO�

BASED O� ESTERIFICATIO� PROCESS TECH�OLOGY

GROUP 28

MUHAMMAD AIMEN BIN ISA 10284

MUNIRAH BINTI SAMSUDDIN 9813

NIK ASMADI BIN AZNAN 9603

AHMAD NIZAR BIN YUNUS 10216

NUR FATHIAH BINTI JASMARI 10233

CHEMICAL ENGINEERING PROGRAMME

UNIVERSITI TEKNOLOGI PETRONAS

Bandar Sri Iskandar, 31750 Tronoh, Perak Darul Ridzuan

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CERTIFICATIO� OF APPROVAL

CAB 4013

PLA�T DESIG� I

July 2010 Semester

I�TERIM REPORT :

POLYETHYLE�E TEREPHTHALATE (PET) PRODUCTIO�

BASED O� ESTERIFICATIO� PROCESS TECH�OLOGY

GROUP 28

MUHAMMAD AIMEN BIN ISA 10284

MUNIRAH BINTI SAMSUDDIN 9813

NIK ASMADI BIN AZNAN 9603

AHMAD NIZAR BIN YUNUS 10216

NUR FATHIAH BINTI JASMARI 10233

APPROVED BY,

( IR. DR. ABD HALIM SHAH MAULUD )

CHEMICAL ENGINEERING PROGRAMME

UNIVERSITI TEKNOLOGI PETRONAS

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EXECUTIVE SUMMARY

Polyethylene Terephtalate is a thermoplastic polymer resin of the polyester family and

most often used to make synthetic fibers, containers for food and beverages, pharmaceuticals,

make-up and other thermoforming applications, where engineering resins often come out in

combination with glass fiber. Polyethylene terephthalate is frequently shortened to PET or

PETE. In order to produce PET, there are two major processes, called esterification and

transesterification, where esterfication used ethylene glycol (EG) and terephthalic acid (TPA)

as its raw material while transesterification used EG and dimethylterephthalate (DMT).

Regarding these two process, both will be further explain in the next chapter as well as why

esterification process is being choose in this project.

Technically speaking, PET is a linear thermoplastic resin that has several advantages,

especially when it’s being used for packaging. PET does not break easily and edibles stored

since it acts as a good barrier to elements outside of the container. The main objective of this

project is to investigate the feasibility of setting up a polyethylene terephthalate (PET)

producing plant based on the selected process technology.

Throughout this project, Chapter 1 will mainly emphasize on the project background,

problem statement as well as scope of work, while the Chapter 2 gives details of the project

background, market survey, properties of chemicals used, site feasibility study and feedstock

supply. The location chosen for the plant is Kerteh because of the availability of raw material

utilities and transportation. On the other hand, Chapter 3 discusses the preliminary hazard

analysis which includes identification of material and chemical hazard, safety aspects in order

to reduce potential accidents and also local safety regulations.

Then analysis on the conceptual process design was done in Chapter 4. It is important

to understand the basic principle of the whole process ; such as what reaction is taken place,

chemical reaction involved and types of reactor that we should used. In this chapter, the plant

is to be operated in continuous mode and the type of reactor used is the conversion reactor.

The separation units required for the process route is including distillation column for the

purification of ethylene glycol (EG) or act a main medium to separate water during reaction.

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In achieving better conversion, unreacted EG is recycled to the main stream. Overall, the

whole process of producing PET was done by using iCON simulation result.

Chapter 5 mainly describes the process flow and process flowsheet as well as manual

calculation on iCON simulation result of material balance. Heat integration calculation is also

mentioned by using pinch technology, in order to maximized energy used. Meanwhile, in

Chapter 6, the description about the process is determine by types of reactor used.

Throughout the project, estimate production rate of the plant is 30,449 ± 1.72 kg/year,

which is equivalent to 30.449 ± 0.00172 tonnes per annum with high purity of PET produced,

98 ± 0.4%. Thus, the proposed plant design will be justified based on the economic potential

of the process, by comparing the price of PET and price of raw materials needed (TPA and

EG). Hence, overall process description on this project will be further explained in each

chapter that has been mentioned earlier.

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ACK�OWLEDGEME�T

Alhamdulillah, thanks to Allah for giving us opportunity to complete this Plant

Design 1 course for this semester after have been struggling with all the problems and

challenges in completing this design project for the past several months.

There were about fourteen (14) weeks have been given to us in completing the design

project in Plant Design Project 1 (CAB4013) course under the supervision of our keen

supervisor, Ir Dr Abd Halim. We as the member of this group would like to pass our highest

gratitude to Ir Dr Abd Halim for all his guidance and continuous supports throughout the

semester. He has been a very supportive supervisor and willing to share his knowledge, in

order ensure that we could learn and understand every single thing in this project. Our

gratitude is also extended to PDP 1 coordinator, Dr. Rajashekhar Pendyala and Dr. Ridza for

their efforts in arranging the iCon seminar and planning the course structures so that we could

complete our project smoothly throughout this whole semester.

Last but not least our appreciation is to our beloved group mates, course mates and

also friends, thanks for all the supports and motivations that help us to complete this project

with a successful ended. Not to forget to those who directly or indirectly involved in giving

us the opportunity to learn and work as a team while designing our first plant project.

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TABLE OF CO�TE�TS

EXECUTIVE SUMMARY ..................................................................................................... 3

ACK�OWLEDGEME�T ....................................................................................................... 5

ALHAMDULILLAH, THA�KS TO ALLAH FOR GIVI�G US OPPORTU�ITY TO

COMPLETE THIS PLA�T DESIG� 1 COURSE FOR THIS SEMESTER AFTER

HAVE BEE� STRUGGLI�G WITH ALL THE PROBLEMS A�D CHALLE�GES I�

COMPLETI�G THIS DESIG� PROJECT FOR THE PAST SEVERAL MO�THS. ... 5

LIST OF FIGURES ................................................................................................................. 9

CHAPTER 1 : I�TRODUCTIO� ........................................................................................ 11

1.1 BACKGROU�D OF DESIG� PROJECT .................................................................................. 11

1.2 PROBLEM STATEME�T ........................................................................................................ 11

FIGURE 1 : GLOBAL PET DEMA�D ............................................................................... 12

1.3 OBJECTIVE ........................................................................................................................... 13

1.4 SCOPE OF WORK .................................................................................................................. 14

CHAPTER 2 : LITERATURE REVIEW ........................................................................... 15

2.1 BACKGROU�D OF DESIG� PROJECT .................................................................................. 15

2.1.1 Overview of product, feedstock and byproducts ........................................................... 15

2.1.2 Process Primary Routes to PET Production ................................................................. 19

2.1.3 Process Alternative Routes ........................................................................................... 20

2.1.4 History, Applications and Usage .................................................................................. 22

2.2 PRODUCT MARKET SURVEY ............................................................................................... 24

2.2.1 Resources and raw Materials ....................................................................................... 24

2.2.2 Global Market Outlook ................................................................................................. 27

2.2.3 Asian Market Outlook ................................................................................................... 28

2.2.4 Overall Market Outlook ................................................................................................ 30

2.2.5 Overall Production Estimation ..................................................................................... 31

SITE FEASIBILITY STUDY ................................................................................................................ 32

2.2.6 Introduction ................................................................................................................... 32

2.2.7 Selection Criteria .......................................................................................................... 32

2.2.8 Contributing Factors in Site Selection .......................................................................... 33

2.2.9 Summary Of Characteristic at Each Location .............................................................. 35

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2.2.10 Concluding Remark ............................................................................................... 41

2.3 PHYSICAL A�D CHEMICAL PROPERTIES ............................................................................ 43

2.3.1 Polyethylene Terephthalate (PET) ................................................................................ 43

2.3.2 Ethylene Glycol (EG) .................................................................................................... 43

2.3.3 Diethyl Glycol (DEG) ................................................................................................... 44

2.3.4 bis-hydroxyethyl terephthalate (BHET) ........................................................................ 44

2.3.5 Terephthalic Acid (TPA) ............................................................................................... 45

2.3.6 Water ............................................................................................................................. 45

2.4 FEEDSTOCK SUPPLY ............................................................................................................ 46

2.4.1 Supplier Profile ............................................................................................................. 46

CHAPTER 3 : PRELEMI�ARY HAZARD A�ALYSIS .................................................. 48

3.1 SAFETY ISSUES A�D PRELIMI�ARY HAZARD A�ALYSIS ................................................... 48

3.2 IDE�TIFICATIO� OF MATERIAL A�D CHEMICAL HAZARD .............................................. 48

3.3 EMERGE�CY SITUATIO� PROCEDURE ............................................................................... 58

3.4 LOCAL SAFETY REGULATIO�S ........................................................................................... 59

CHAPTER 4: CO�CEPTUAL DESIG� A�ALYSIS ....................................................... 62

4.1 PRELIMINARY REACTOR OPTIMIZATION .................................................................................... 62

4.1.1 Reactions Involved ......................................................................................................... 62

4.1.2 Esterification Reaction .................................................................................................. 62

4.1.3 Polymerization Reactions .............................................................................................. 64

4.2 PROCESS SCREE�I�G .......................................................................................................... 66

4.2.1 Heuristic Approach for Separation System Synthesis.................................................... 66

4.2.2 Sequencing of Separators .............................................................................................. 66

4.2.3 Operating Conditions for Separators ............................................................................ 68

4.3 ECO�OMIC POTE�TIAL (EP) .............................................................................................. 69

4.3.1 Economy Analysis .......................................................................................................... 69

4.3.2 Total Capital Investment ............................................................................................... 69

4.3.3 Fixed Capital Investment .............................................................................................. 70

4.3.4 Working Capital Investment .......................................................................................... 72

4.3.5 Start Up Cost ................................................................................................................. 72

4.3.6 Total Capital Investment ............................................................................................... 73

4.3.7 Utilities .......................................................................................................................... 73

4.4 MASS BALANCE BY MANUAL CALCULATION & ICON SIMULATION ......................................... 77

4.4.1 Block Diagram for Production of PET Process ............................................................ 82

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CHAPTER 5 : HEAT I�TEGRATIO� .............................................................................. 83

5.1 PI�CH A�ALYSIS .................................................................................................................. 83

5.5.1 Pre-design Target for Utility Consumption .................................................................. 83

5.2 DIFFERE�CE I� HEAT EXCHA�GER DUTY REQUIREME�T BEFORE A�D AFTER HEAT

I�TEGRATIO� (HI) .......................................................................................................................... 90

CHAPTER 6 : PROCESS DESCRIPTIO� ........................................................................ 91

6.1 PROCESS DESCRIPTION ............................................................................................................... 91

6.2 FEED RAW MATERIAL ................................................................................................................ 92

6.3 REACTIONS INVOLVED................................................................................................................ 92

6.31 Esterification Process ..................................................................................................... 92

6.32 Separation Process ......................................................................................................... 93

6.33 Purging system ............................................................................................................... 95

6.34 Polycondensation Process .............................................................................................. 96

CHAPTER 7 : CO�CLUSIO�S .......................................................................................... 99

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LIST OF FIGURES

Figure 1 : Global PET Demand ............................................................................................... 12

Figure 2 : Usage of PET........................................................................................................... 24

Figure 3 : World Consumption of Ethylene Glycol ................................................................. 25

Figure 4 : Usage of Ethylene Glycol........................................................................................ 24

Figure 5 : World Consumption of TPA ................................................................................... 26

Figure 6 : TPA World Consumption In Year 2009.................................................................. 27

Figure 7 : Global PET Demand by Regions ............................................................................ 28

Figure 8 : World Consumption of PET Resins ........................................................................ 29

Figure 9: Tariff for High Voltage Industries............................................................................ 70

Figure 10 : Overall Esterifiction Reaction ............................................................................... 60

Figure 11 : Pre-Polycondensation Reaction ............................................................................. 61

Figure 12 : Final Polycondensation Reaction .......................................................................... 62

Figure 13 : Block Diagram of the Process ............................................................................... 80

Figure 14: Heat Balance By Manual Calculation .................................................................... 82

Figure 15 : Problem table Algorithm By manual Calculation ................................................. 83

Figure 16 : Composite Curve generated by using Aspen HX-Net 2006 software ................... 85

Figure 17 : Grand Composite Curve generated by using Aspen HX-Net 2006 software ........ 86

Figure 18 : Heat Exchanger Network ...................................................................................... 87

Figure 19 : Reaction Flow of PET Production......................................................................... 89

Figure 20 : Esterification Process ............................................................................................ 91

Figure 21 : Series of Esterification Reactor ............................................................................. 91

Figure 22 : Ethylene Glycol Recovery System ........................................................................ 92

Figure 23 : Purging Syatem ..................................................................................................... 93

Figure 24 : Series of Polycondensation Process ...................................................................... 95

Figure 25 : Reactions of Functional Group in PET Production Stage ..................................... 96

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LIST OF TABLES

Table 1 : Contributing Factors to Operability and Economy Aspects ..................................... 30

Table 2 : Summary Of Justification On Site Location ............................................................. 35

Table 3 : Weighted marks and explanation on the plant site location factors ......................... 38

Table 4 : Weight Matrix On Site Location .............................................................................. 39

Table 5 : PET Properties .......................................................................................................... 41

Table 6 : EG Properties ............................................................................................................ 41

Table 7 : DEG Properties ......................................................................................................... 42

Table 8 : BHET Properties ....................................................................................................... 42

Table 9 : TPA Properties.......................................................................................................... 43

Table 10 : Water Properties ..................................................................................................... 43

Table 11 : Equipment Required and Estimated cost for PET Plant ......................................... 67

Table 12 : Fixed Capital Investment for PET Production Plant .............................................. 68

Table 13 : Plant Utilities ......................................................................................................... 71

Table 14 : MSDS for Selected Chemical ................................................................................. 47

Table 15 : Safety Risk and Mitigation Measures ..................................................................... 54

Table 16 : Separators with types of mixtures and Operating Condition .................................. 65

Table 17: Data from iCon Simulation ...................................................................................... 81

Table 18 : Summary Of % Saving After Heat Integration ....................................................... 88

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CHAPTER 1 : I�TRODUCTIO�

1.1 Background of Design Project

Polyethylene Terephthalate (PET) has been widely used, especially when plastics

bottles or food container popped-out in our mind. Thus, the advantages of PET have been

explored to understand its importance in industries. In Malaysia, we do understand that there

is no PET production plant exists, but somehow, Malaysia does have several companies

whom buy PET from other countries and process PET into plastics or any other necessary

PET-based products. These companies act as a supplier to supply and process PET, before

they distribute them in the form of desired products. Referring to our title ‘PET Production

Based On Esterification Process’, there are two basic raw material involved, which consists

of Ethylene Glycol (EG) and Terephthalic Acid (TPA).

Consequently, depending on PET processing and thermal history, PET may exist both

as an amorphous (transparent) or as a semi-crystalline material. The semi-crystalline material

might appear transparent or opaque and white, depends on its crystal structure and particle

size. During esterification process, reaction between Ethylene Glycol (EG) and Terephthalic

Acid (TPA) will produce monomer bis-hydroxyethyl terephthalate (BHET) and water as

byproduct.

1.2 Problem Statement

Based on the increasing number of PET demand, a petrochemical plant of

Polyethylene Terephthalate (PET) has been discussed to be constructed in Malaysia. As being

mentioned earlier, PET production plant will considered esterification process as its produce

only water as its byproduct. Generally, the plant is expected to operate for 330 days in a year,

including maintenance work or plant shutdown. The interest rate for the project is estimated

to be 10% per year and the project life is about 20 years. Thus, the whole study about this

coming construction plant needs to be developed to cater its manufacture and economical

feasible production capacity.

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The majority of the world's PET production is for synthetic fibers (in excess of 60%)

with bottle production accounting for around 30% of global demand. In discussing textile

applications, PET is generally referred to as simply "polyester" while "PET" is used most

often to refer to packaging applications. PET consists of polymerized units of the monomer

ethylene terephthalate, with repeating C10H8O4 units. PET is commonly recycled, and has the

number "1" as its recycling symbol.

Referring to below diagram on the Global PET demand, it is expected that year 2020

will needed huge amount of PET, which is approximately reaching 27 Million Tons. As the

demand increase proportionally with time, huge PET production is also expected to increase

by the existing number of plant or manufacture. By also considering the usage of PET

whether in industries or non-industries, Malaysia is about to take one step ahead in planning

and setting up a new plant for its own benefits.

Figure 1 : Global PET Demand

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1.3 Objective

Plant Design Project (PDP) 1 has come out with its own objective, especially to

educate and develop simulation skills among students. The project of designing industrial

plant required knowledge, passion and attitude in solving design problems for typical process

exists in industrial plant. Hence, this project is given with its own purpose ;

• To complete the design of PET Production plant by conducting literature survey,

which includes its process routes, properties, uses, and market cost data.

• To identify chemical and physical properties for all raw materials, intermediate

products, final products and environmental and safety considerations.

• To study and select the best process route of producing PET for a selected design

project (chosen process - esterification).

• To perform energy balance calculations and apply related computer-aided design

engineering software (iCON) as a tool for the design.

• To make necessary decisions, judgments and assumptions in design problems.

• To execute the process design and mechanical design of the major process units by

doing research on equipment used.

• To perform economic evaluation including capital cost estimation and manufacturing

cost estimation.

• To understand the environmental and safety issues related to the plant, by discussing

potential chemical hazard in the process.

• To develop working skills in a team and understand the basic principles of plant

design as well as reaction involved

• To generate cost effective process and maintain operation safety

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1.4 Scope of Work

There are several guidelines or scope of work that has been highlighted in this design

project, which mainly includes ;

• Conduct literature review survey about the product including its properties, usage,

cost, process involved, chemical and physical properties of raw materials, final

products, environmental considerations and safety considerations

• A clear complete Process Flow Diagram (PFD) of optimized process including all the

equipment.

• Provide stream flow table including all the stream variables e.g. temperature,

pressure, total flow rate and component flow rate.

• Identify and select the best process route for this design project

• Develop and performed complete material and energy balance calculations for

selected process

• Use related computer-aided design/engineering software (e.g. iCON, HYSYS, Visio

and Microsoft Excel) as the main tools for the design

• Make necessary decisions, judgments and assumptions based on plant design

knowledge, especially to solve design problems

• Perform economic evaluation including economic potential and initial cost estimation

• Consider environmental and safety issues which related to the plant

• Prepare preliminary and interim report as per standard format and do a presentation

on the design plant

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CHAPTER 2 : LITERATURE REVIEW

2.1 Background of Design Project

2.1.1 Overview of product, feedstock and byproducts

Product : Polyethylene Terephthalate (PET)

Polyethylene Terephthalate (PET)

In the 1950s, Polyethylene terephthalate (PET) came into prominence as a textile

material. PET is supplied by resin manufacturers in the form of small pellets, which each of

them are approximately 0.05 gram in size. Its strength, temperature tolerance and wear-

resistance made it an ideal replacement for or addition to natural fibers such as silk, cotton

and wool. PET is also a linear thermoplastic, which have long-chain molecule and consists of

repeating units, with white but bluish characteristics of resin. PET is made from terephthalic

acid and ethylene glycol through poly-condensation.

PET is also belongs to semi-crystalline polymer group and when heated above 72°C,

PET will change from a rigid glass-like state into a rubbery elastic form. In this condition,

polymer molecular chains can be stretched and aligned in either one direction to form fibres,

or in two directions to form films and bottles. Consequently, if the material melt is cooled

quickly, the chains will be frozen, with their orientation remaining intact in the stretched

state. Crystallization of PET in this condition makes the material starts to become opaque,

more rigid and less flexible. However, nowadays, many modifications are introduced to

develop specific properties for the various packaging applications to suit particular

manufacturing equipment. Special grades are offered with the required properties for the

different applications.

In industries, the best thing about PET is that it can be recycled to make many new

products, including fiber for polyester carpet; fabric for T-shirts, long underwear, athletic

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shoes, luggage, upholstery and sweaters; fiberfill for sleeping bags and winter coats; and new

PET containers for both food and non-food products.

By recycling, there are lots of advantages has been proved, such as ;

• Recycling a ton of PET containers saves 7.4 cubic yards of landfill space.

• According to the EPA, recycling a pound of PET saves approximately 12,000

BTU's.

• The average household generated 42 pounds of PET plastic bottles in the year

2005.

• Custom bottles (which are bottles used for products other than carbonated soft

drinks) represent 62% of all PET bottles available for recycling.

Feedstock : Terephthalic Acid (TPA) and Ethylene Glycol (EG)

Terephthalic Acid (TPA)

Terephthalic acid is an organic compound with formula C6H4(COOH)2. The

abbreviation used for this acid is TPA. The common properties for TPA are colorless solid,

and it is being used in the application of polyester PET, especially for clothing and plastic

bottles. In industries, several billion kilograms are produced annually to cater the needs of

TPA in many sectors. TPA also considered as one of the three isomeric phthalic acids. In this

project, TPA used is assume to be 100% purified. Another characteristic for terephthalic acid

is including poorly soluble in water and alcohols, and most of the crude terephthalic acid was

converted to dimethyl ester for purification. PTA also sublimes when heated (since it is

already mentioned that PTA is in a solid condition).

Virtually the entire world's supply of terephthalic acid is consumed as precursors to

polyethylene terephthalate (PET), as TPA is plays very important role for PET production

(raw material). With lots of application of PTA, by 2006, global purified terephthalic acid

(PTA) demand had exceeded 30 million tonnes. While in the research laboratory, terephthalic

acid has been popularized as a component for the synthesis of metal-organic frameworks.

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Ethylene Glycol (EG)

Ethylene glycol is an organic compound widely used as an automotive antifreeze and

also the main precursor to polymers. Ethylene glycol falls under alcohol group with formula

C2H6O2. The short form for ethylene glycol is EG, where in its pure form, it is odorless,

colorless, syrupy and sweet-tasting liquid. Ethylene glycol is also known to be toxic, and

ingestion can result in death.

Ethylene glycol is produced from ethylene (ethene), via the intermediate ethylene

oxide. In this reaction, the major byproducts are ethylene glycol oligomers, diethylene glycol,

triethylene glycol, and tetraethylene glycol. In industries, about 6.7 billion kilograms of EG

are produced annually. Another application of EG are includes ; medium for coolant and heat

transfer, hydration inhibition to remove water and inorganic salts, and in niche application.

Byproducts : Diethyl glycol (DEG), bis-hydroxyethyl terephthalate (BHET) and Water

Diethyl glycol (DEG)

Diethyl glycol (DEG) is a class of organic chemicals groups that contribute to high

water solubility and reactivity with many organic compounds, usually linear and aliphatic

carbon chain. The general formula for DEG is O(CH2CH2OH)2. Ethylene glycol is the

simplest member of the glycol family. Mono-, di- and triethylene glycols are the first three

members of a homologous series of dihydroxy alcohols. The basic characteristic of EG is a

colorless, odorless, involatile and hygroscopic liquid with a sweet taste. It is somewhat

viscous liquid, which miscible with water. In plastic industries, EG has become increasingly

important for the manufacture of polyester fibers and resins, including polyethylene

terephthalate, which is used to make plastic bottles for soft drinks (PET bottles). Ethylene

glycol is by far the largest volume of the glycol products in a variety of applications including

anti-freezing additive, intermediate polymer, solvent or plasticizer for plastic, dehydrating

and textile conditioning.

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bis-hydroxyethyl terephthalate (BHET)

Throughout this project, bis-hydroxyethyl terephthalate (BHET) is known as

monomer in the production of PET. BHET is then polymerized up to about 30 in

polymerization process. One of the characteristic found in BHET is that it is obtained as an

amorphous to very finely crystalline mass and difficult to separate. This BHET can undergo

polycondensation process and to be removed during PET production process without any

further additives. However, polycondensation of BHET with the addition of a corresponding

molar amount of terephthalic acid makes it possible to utilize this ethylene glycol to produce

huge amount of PET.

Water (H2O)

In this project of PET production plant, we have decided to choose esterification

process as the main route. Thus, the main byproduct produced is water. Water is widely

known as a liquid at ambient conditions, but it often co-exists on Earth with its solid state,

ice, and gaseous state, water vapor or steam. Water is a tasteless, odorless liquid at standard

temperature and pressure. The color of water and ice is, intrinsically, a very slight blue hue,

although water appears colorless in small quantities. Water is also transparent, where sunlight

can be seen through water.

Water is a good solvent and is often referred to as the universal solvent. Substances

that dissolve in water, for example ; salts, sugars, acids, alkalis, and some gases – especially

oxygen, carbon dioxide (carbonation) are known as hydrophilic (water-loving) substances,

while those that do not mix well with water such as fats and oils, are known as hydrophobic

(water-fearing) substances. All the major components in cells (proteins, DNA and

polysaccharides) are also dissolved in water. Pure water has a low electrical conductivity, but

this increases significantly with the dissolution of a small amount of ionic material.

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2.1.2 Process Primary Routes to PET Production

Production of Polyethylene Terephthalate (PET) has two major processes, which are

esterification and transesterification. In this project, we have decided to choose esterification

process instead of transesterification process. In this context, overview of feedstock, product

and byproducts will be highlighted, while details about transesterification process will be

discussed later in the process alternative routes, where we put this process as our second

option. By referring to esterification basic definition, the process is the general name for a

chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as

the reaction product. During the process, main chemicals involved are ethylene glycol (EG)

and terephthalic acid (TPA) with water as the byproducts.

The primary reaction for esterification process is ;

During the process, ethylene glycol (EG) and terephthalate acid (TPA) react with each other

at 190°C in the presence of an inert gas, such as nitrogen, yielding bis-hydroxyethyl

terephthalate (BHET) :

bis-hydroxyethyl terephthalate (BHET)

The terephthalic acid and ethylene glycol are mixed to form a paste, allowing more

accurate control of the feed rates to the esterification vessels. The number of reactors and

their operating conditions depends on the type of PET being produced. In this case, ratio of

EG and TPA is 1:1.2 respectively (by considering recycle stream). Typically, in this process,

there are two stage of esterification processes, two stage of polycondensation process and one

distillation column involved mainly for water removing. Esterification process 1 converts

95% of reaction involved while the second process converts 98% of the first reaction. As for

polymerization process, both processes are assumed to be 100% conversion.

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Consequently, TPA and EG process generally involves a system similar to that of the

DMT process. The major difference is the lack of a methanol recovery step and it involved

only one catalysts ; Antimony Trioxide.

2.1.3 Process Alternative Routes

One of the alternative PET process routes is known as transesterification.

Transesterification process used dimethylterephthalate (DMT) and ethylene glycol (EG). In

this process, EG is drawn from raw material storage and fed to a mix tank, where catalysts

and additives are mixed along with DMT, to the esterifiers. This reaction produces the

intermediate BHET monomer and methanol as the byproduct. During transesterification,

methanol vapor must be removed from the esterifiers to shift the conversion to produce more

BHET.

Chemical reaction involved during transesterification ;

The BHET monomer, with other esterifier products, is fed to a polymerization reactor

where the temperature is increased and the pressure is decreased. At these operating

conditions, residual methanol and ethylene glycol are vaporized, and the reaction that

produces PET resin starts, where the final temperature and pressure depend on whether low

or high viscosity PET is being produced. For high-viscosity PET, more process vessels are

used to achieve higher temperatures and lower pressures, compared to low-viscosity.

Throughout this process, ethylene glycol can be recovered by using recovery system,

which is usually a distillation composed of a low boiler column, a refining column, and

associated equipment. Product from the polymerization reactor (referred to as the polymer

melt) may be sent directly to fiber spinning and drawing operations. Alternatively, the

polymer melt may be chipped or pelletized, put into product analysis bins, and then sent to

product storage before being loaded into hoppers for shipment to the customer.

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Below is a simple comparison between the two existence process, esterification and

transesterification ;

Based on above table, esterification process involved EG and TPA as its raw material

and produced water as the byproducts. Since the technology was introduced in year 1963, it is

newer process than transesterification process. Water can be recycled to other types of usage

such as for reducing heat, thus it lower down the process cost for cooling purposes. Water

produced is less harmful to the environment since it contains low VOC (Volatile Organic

Compound) number. While for transesterification process, it has been introduced since year

1940 where the chemicals involved are EG and DMT. The process produced methanol as the

byproduct, thus it is crucial to establish recovery unit for methanol. This might increase plant

cost. Transesterification also produce hazardous material where the VOC content is high and

lead to respiratory problem.

ESTERIFICATIO� DETAILS TRA�SESTERIFICATIO�

New Technology - 1963 History Old Technology – 1940

EG + TPA Raw material EG + DMT

Produce H20 By product Produce Methanol

H20 can be recycled for

other usage (Low Cost) Recovery Unit

Need to establish Recovery

Unit (High cost)

No unit required Purification unit Required for methanol recovery

Less harm to environment

(Low VOC content) Environments

Produce hazardous material

(Higher VOC content),

Lead to respiratory problem

Table 1 : Process Comparison

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2.1.4 History, Applications and Usage

PET History

Polyethylene was discovered in 1933 by Reginald Gibson and Eric Fawcett at British

industrial giant Imperial Chemical Industries (ICI). There are two material forms, which is

low density polyethylene (LDPE) and high density polyethylene (HDPE). In early 1950s,

polypropylene (PP) was discovered after the existence of polyethylene. Polypropylene was

invented by two American chemists, who worked for Phillips Petroleum of the Netherlands,

Paul Hogan and Robert Banks. Previously, before PET was introduced, polypropylene is

being used in almost everything ; from plastic bottles to carpets to plastic furniture, and also

heavily used in automobiles.

In year 1941, John Rex Whinfield and James Tennant Dickson, British chemists and

employee of a company named Calico Printer's Association of Manchester, has patented

‘polyethylene terephthalate’ or also known as PET or PETE. It is actually a continuous effort

from early research of Wallace Carothers, who is an American chemist, inventor and the

leader of organic chemistry. Realizing that Carothers's research had not investigated polyester

formed from ethylene glycol and terephthalic acid, Whinfield and Dickson took this

opportunity along with inventors W.K. Birtwhistle and C.G. Ritchiethey to create the first

polyester fiber called Terylene in the same year, 1941.

According to Whinfield and Dickson, polyethylene terephthalate is the basis of

synthetic fibers such as polyester, dacron, and terylene, while the second polyester fiber was

from DuPont's Dacron company. According to DuPont, there was indirect competition with

Britain’s recently formed Imperial Chemical Industries in the late 1920s. Thus, in October

1929, both companies agreed to share information about patents and research developments.

However, even after both companies alliance, DuPont chose to concentrate more on the

promising nylon research. When DuPont resumed its polyester research, ICI had patented

Terylene polyester, to which DuPont purchased the U.S. rights in 1945 for further

development. In 1950, a pilot plant at Seaford, Delaware, was established to produced

Dacron, or polyester fiber with modified nylon technology. Dupont's polyester research lead

23

to a whole range of trademarked products, for example is Mylar (1952), an extraordinarily

strong polyester (PET) film that grew out of the development of Dacron in the early 1950s.

As being mentioned earlier, polyesters are made from chemical substances found

mainly in petroleum and are manufactured in fibers, films, and plastics. According to Dupont

Teijin Films, plain polyethylene terephthalate (PET) or polyester is most commonly

associated with a material from which cloth and high-performance clothing are produced.

Over the last ten years PET has increasingly gained acceptance as a material of choice

especially for beverage bottles. Other that PET, glycolised polyester (PETG) is also being

used in the production of cards. While polyester film (PETF), a semi-crystalline film has

proved its importance in many applications such as videotape, high quality packaging,

professional photographic printing, X-ray film, as well as floppy disks.

PET Application and Usage

Nowadays, polyethylene terephthalate (PET) has been widely used in our daily life, as

it is cheap, flexible, durable, and chemically resistant. As mentioned earlier, two types of

materials formed, which are low density polyethylene (LDPE) and high density polyethylene

(HDPE). LDPE is used to make films and packaging materials, including plastic bags, while

HDPE is used more often to make containers, plumbing, and automotive fittings. In addition,

PET is more impermeable than other low-cost plastics, where this condition has help PET to

become a popular material, especially for making drinking bottles for a giant company, Coke.

PET is also strong and abrasion resistant, and is used for making mechanical parts,

food trays, and other items that have to endure abuse. PET films, which its trade-named is

‘Mylar’ are used to make recording tape. PET manufacturing process has been developed by

using various forming, molding, casting, and extrusion processes, to churn out plastic

products in vast quantities. Other than mentioned PET applications, one of the most visible

parts of this plastics invasion was Earl Tupper's or famously known as ‘Tupperware’. The

Tupperware line of products was well thought out and highly effective, greatly reducing

spoilage of foods in storage. Thin-film "plastic wrap" that could be purchased in rolls also

helped keep food fresh.

24

Another prominent element in 1950s homes was "formica," a plastic laminate that

was used to surface furniture and cabinetry. Formica was durable and attractive. It was

particularly useful in kitchens, as it did not absorb, and could be easily cleaned of stains from

food preparation, such as blood or grease. With formica, a very attractive and well-built table

could be built using low-cost and lightweight plywood with formica covering, rather than

expensive and heavy hardwoods like oak or mahogany. Apart from that, composite materials

like fiberglass came into use for building boats and, in some cases, cars.

From above discussions, PET has been proved that it is widely used in our daily life

as the demand of PET is kept increasing. Thus, PET production plant is become crucial to be

built in Malaysia to cater the needs of recent PET products. Summary of PET usage has been

summarize as per below diagram ;

Figure 2 : Usage of PET

2.2 Product Market Survey

2.2.1 Resources and raw Materials

This project of producing PET is proposed to follow easterification process, where

raw materials involved are ethylene glycol (EG) and terephthalic acid (TPA). Further

explanations on both chemicals are as follows ;

25

Ethylene Glycol (EG)

Below figure emphasized on the world consumption of Ethylene Glocol, where Asia

has falls under top five of EG consumer.

Figure 3 : World Consumption of Ethylene Glycol

By taking Malaysia into considerations, the consumption of EG is also considered

higher. Thus, large amount of EG is needed for various types of industries. Ethylene glycol is

a colorless, odorless, low-volatility, low-viscosity hygroscopic liquid. It is completely

miscible with water and many organic liquids. In industries, there are at least five grades of

ethylene glycol are manufactured, which include commercial polyester, industrial, low

conductivity, polyester, and antifreeze.

Figure 4 : Usage of Ethylene Glycol

26

Referring to Figure 4, in 2009, almost 85% of the ethylene glycol (EG) is consumed

worldwide into the production of PET, which in turn was converted into fibers, film and

bottles. Another 10% was consumed in antifreeze and 5.5% in other uses. In 2009, 69% of

the EG consumed worldwide was in Asia, followed by 13% in North America and 8% in

Western Europe. With the huge amount needed for PET production, EG production must also

be increase from time to time to catch up with its consumption.

Terephthalic Acid (TPA)

Consumption of TPA for the production of PET polymer has been more than 90% of

the worldwide consumption. The following pie chart shows world consumption of TPA ;

Figure 5 : World Consumption of TPA

By taking the year of 2009 as TPA based world consumption, more than 60% of the

TPA produced in the world is used to manufacture PET polymer for polyester fibers. Another

31% goes into the manufacture of PET solid-state resin for bottles and other packaging

applications.

27

Figure 6 : TPA World Consumption In Year 2009

TPA for PET solid-state resins has grown strongly followed by the replacement of

glass in soft drinks and water bottles. In five years, PET solid-state resins are estimated to be

the fastest-growing sector in the next five years. Referring to Figure 4, Asia falls under fifth

major contributor to consume TPA, where the opportunity to set up PET production plant is

being study in Malaysia.

2.2.2 Global Market Outlook

PET packaging resin markets have seen very strong growth over the last 20 years. It

first penetrated the carbonated soft drinks market because it is lightweight and strong. PET

bottles are virtually unbreakable while a typical 1.5 litre bottle weighs about 40-45gm, about

one-tenth the weight of glass. PET has taken market share in the bottled water market due to

its good clarity and not leaving any taste in the water. It has also found applications in more

niche markets such as sports drinks and fruit juices, and is used to make bottles for cooking

and salad oils, sauces and dressings.

An untapped market for PET is beer packaging with substantial conversion where it

has captured 5% of the beer market, 62% of glass and 33% of metal cans, according to

Canadean, the UK-based beverage research consultant, while the largest market is Russia,

which accounts for 60% of PET’s use in the global beer market. Other east European

countries are prominent users, but outside these countries, only Germany, South Korea and

Spain make any significant contribution to PET use for beer packaging.

28

The highest demand for PET is Asia, which its demand by volume for PET in 2009

was nearly 4.7 million tons, while Europe is the second largest consumer of PET in the

world. Russia, Italy and Germany are the major consuming countries in Europe. The demand

in some Western European countries, such as Germany, France, Spain and the UK, is

approaching the maturity stage. Growth in European PET demand is driven mostly by Russia.

The demand for PET in Europe was around 3.7 million tons in 2009. The North American

economy is the most developed and advanced, and the scope for growth is lowest as the

demand is close to saturation. However, certain new and upcoming applications of PET are

driving the North American market. The North American demand for PET in 2009 was close

to 3.1 million tons in 2009. The PET demand in South and Central America is growing fairly

strongly. This region consumed around 2 million tons of PET in the year 2009. The Middle

East and African demand for PET is the second fastest growing after that of Asia. The Middle

East and Africa region consumed around 1.2 million tons PET in 2009.

Then again, factor that could impact the supply and demand balance for PET is the

growth in recycling. PET is probably the most recycled polymer taken and being increasingly

used in bottles and retail packaging as well as carpet fiber and clothing. Still, the Global

Market outlook for PET is expected to grow based on the global demand for over the last

decade. The global PET market in 2009 was about 15.3 million tons. In the year of 2020, the

consumption demand for PET is estimated to grow at CAGR of 4.9%.

2.2.3 Asian Market Outlook

Based on Figure 7 on the demand shares by region, shows that Asia is the biggest

consumer of PET with 30.5%, followed by Europe 24%, North America 20.3%, South and

Central America 13.4%, Middle East and Africa 8% and other region is about 3.7%. Thus, it

makes the highest demand for PET is Asia, which its demand by volume for PET in 2009 was

nearly 4.7 million tons.

29

Since the growth in PET demand is coming from Asia, the Gross Domestic Product

(GDP) countries like China and India in Asia are growing at rates higher than the global GDP

growth rates. Thus, the key markets consuming PET are also growing with strong economic

growth along large population that enables large consumption of Carbonated Soft Drinks

(CSDs) and bottled water in the region. Another factor that supports PET demand is rapid

changing of lifestyle that consumes packaged food.

In Asia, China is the largest producer of PET in the region and exports to many

countries as well as the largest PET consuming markets are Carbonated Soft Drinks (CSD)

and Bottled Water. This is due to its light weight, toughness and clarity, PET is the most

preferred material for CSD bottles. CSD and bottled water together account for more than

65% of the global PET demand. However, the packaged food segment is also a very

important and growing market for PET.

Figure 7 : Global PET Demand by Regions

30

2.2.4 Overall Market Outlook

Development and growth of the global PET solid-state resin market since 1996 has

been impressive after their thirty-two years of introduction in the mid-1970s. Global

consumption of these resins continues to grow especially in these three regions ; North

America, Europe and Asia, which accounted for the majority of world production and

consumption. Asia and Middle East are expected to achieve double-digit consumption growth

through 2012, while Eastern Europe and South America have created import opportunities.

Asian and Middle Eastern producers are expected to be the major suppliers of PET exports to

Eastern Europe, Central and South America, and Oceania as its continuous production and

relatively lower feedstock costs as the primary drivers.

The following pie chart shows world consumption of PET solid-state resins:

PET bottle resin is a very important material driving growth in the developed

economies, but growth of PET fiber remains dominant in terms of total polyester. PET

growth is driven differently depending on the geographic region. In North America and

Western Europe, PET growth is associated primarily with PET bottle resins; demand for PET

fiber has been in decline since the late 1990s. PET growth in most other regions is primarily

associated with PET fiber. Global polyester growth will continue to be driven by Asia and,

more specifically, by the Chinese market.

Figure 8 : World Consumption of PET Resins

31

2.2.5 Overall Production Estimation

To estimate the production capacity of a new polyethylene terephthalate (PET) plant,

we assume that the production capacity of world depends largely on the world population. In

2015, the world population is estimated to be around 6.8 billion people. We assume that we

want to produce PET solely in Malaysia. To estimate the amount of PET to produce, we need

to do a calculation based on the population in Malaysia and the world’s population.

Based on “Catalytic and Mechanistic Studies of PET Synthesis” by Faissal-Ali El-Toufaili, in

2015, the PET demand in 2015 is about 58 x 106 MT/yr.

Calculation:

32

Site Feasibility Study

2.2.6 Introduction

Choosing strategic plant location is one of the most crucial decisions needs to be

done. The construction of a chemical plant requires a preliminary feasibility study to be done

in order to make certain that the proposed 30,000 kg/year PET plant is feasible, economically

and environmentally. The location of the plant site takes relatively high precedence and it

mainly depends on the availability of feedstock, cost of production, marketing of the

products, land availability and also the infrastructure. The right location allows maximum

profit with a minimum operating cost and allowance for future expansion.

2.2.7 Selection Criteria

Based on the study done in the selecting strategic plant location, there are several

factors that should be taken into consideration when undertaking the process of selecting a

suitable site. There are two major factors that contribute to the operability and economic

aspects of a site location for a plant, which are the primary factor and specific factor.

Table 2 : Contributing Factors to Operability and Economy Aspects

Primary Factors Specific Factors

1. Raw material availability for

industry

Availability of low cost labor and

services

2. Reasonable land price Safety and environmental impacts

3. Source of utilities, such as

electricity, water and etc.

Incentives given by government :

Pioneer Status

Investment Tax Allowance (ITA)

Effluent and waste disposal facilities

4. Climate status

Wind

Rainfall

Temperature

Relative Humidity

Transportation facilities

Local community consideration

33

2.2.8 Contributing Factors in Site Selection

General Factors

i. Availability of Raw Material

To minimize the transportation cost of the raw material, a closer source of the

raw material to the operating plant is needed. If the needed raw material is to be

imported, it would be important to consider a location near to a seaport with excellent

infrastructure.

ii. Reasonable land price

Most of the industrial land price depends on the location. It is very important

to choose an economical land price which can reduce the total investment cost.

Besides that, it is important to choose the lowest land price when starting a new plant

to gain the highest economic value.

iii. Utilities

In petrochemical industries, large quantities of water supply are usually

needed for cooling and general use in a chemical plant. Besides that, petrochemical

plants need power in the form of electricity to run machines and equipments. Thus it

is important to have sufficient power and local water supply in order to ensure the

plant running smoothly.

iv. Climate

Budget and cost operation can be affected by climatic conditions. A general

analysis of the yearly weather conditions would be an important consideration.

34

Specific Factors

i. Availability of low cost labor and services

Plant should be located where sufficient labor supply is available. Skilled

construction workers will usually be brought in from outside local area but there

should be an adequate pool of unskilled workers available locally and workers

suitable for training to operate the plant. Available, inexpensive manpower from the

surrounding area will contribute in reducing the cost of operation.

ii. Transport facilities

The plant should be located close to at least three forms of major

transportation facilities, which are road network, seaport and airport. These will help

facilitate any import and export activities. Seaport facilities will help in the

exportation and importation of the product and raw materials via tankers while the

availability of airport is convenient for the movement of personnel and essential

equipment supplies.

iii. Government incentives

Most state governments offer attractive incentives to investors. Some

incentives grant partial or total relief from income tax payment for a specified period,

while indirect tax incentives come in the form of exemptions from import duty, sales

tax and excise duty. This can help reduce initial operating costs.

iv. Local community consideration

The proposed plant will have to fit in with and acceptable to the local

community. Full consideration must be given to be safe location of the plant so that it

does not impose a significant additional risk to the community. On a new site, a local

community must be able to provide adequate facilities for the plant personnel: school,

banks, housing, and recreational and cultural facilities.

35

v. Waste and effluent disposal facilities

Site selected should have efficient and satisfactory disposal system for factory

waste and industrial effluent if it is decided that the waste should be treated off-site.

2.2.9 Summary Of Characteristic at Each Location

The manufacture of PET is categorized as a petrochemical project. The plant must

therefore be sited in a special zone provided by the government. After conducting the

feasibility and site survey, four (4) main locations have been short listed to be considered as

strategic site location for the construction of a 30,000 kg/year, PET plant.

i) Kerteh Industrial Estate,Terengganu

Kertih Integrated Petrochemical Complex, Terengganu located at the south of

Terengganu, is developed by PETRONAS. Plants can be sited within the vicinity of

raw materials thus saving in production cost. Availability of cheap industrial land and

supply of relatively productive and adaptable labor from a young and literate

population give merit to the location. Special incentives are offered such as cheaper

land and lower quit rent and assessment rates. Terengganu is also home of the

Malaysia deepest port versioned to be the new gateway to the Asia Pacific.

ii) Gebeng (Phase IV) Industrial Estates, Kuantan, Pahang.

Gebeng Industrial Estate is promoted by the Pahang State Development

Corporation (PSDC) as an industrial predecessor in the East Asian region for

petrochemical and chemical based plants. The federal government’s move to develop

the eastern industrial corridor ensures beneficial and rapid progression for the

industrial growth of Gebeng estate. According to Kuantan Port Consortium (2007),

the first and second phase category, comprises about 900 hectares. A third phase,

spanning some 1,600 hectares, has attracted mega industries from multinational

companies, namely from the US, Japan, Germany and Belgium. Kuantan proximity to

Malaysia’s oil and gas fields make it a logical choice for petrochemical industry

growth.

36

iii) Teluk Kalong Industrial Estate, Terengganu.

Teluk Kalong is an industrial town of Kemaman district, Terengganu,

Malaysia. Teluk Kalong insdustrial Estate was built by Terengganu State through

Perbadanan Memajukan Iktisad Negeri Terengganu (PMINT) to support petroleum

industry at Terengganu. It is located at strategic location which is 35 minutes to

Gebeng Kuantan Industrial Area and 40 minutes to Kerteh Industrial Area.

iv) Pasir Gudang, Industrial Estate,Johor.

Pasir Gudang, Industrial Estate is located 36 km from Johor Bahru. The type

of industry develop in Pasir Gudang is light, medium and heavy industry. Johor Port

is about 5 km from Pasir Gudang, and this will enable easier import and export

processes. Good infrastructure facilities are also available here, such as North-South

highway to Kuala Lumpur and the main road to Singapore. Railroads are also

available here. The line runs from northern terminal in Butterworth to Singapore and

Pasir Gudang in the South.

Evaluation for each site location was made which is based on primary and specific

factor which had been justified earlier. Summary of justification can be seen in Table 2 and

Table 3.

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ts

Pio

nee

r S

tatu

s an

d I

nves

tmen

t

Tax

All

ow

ance

an

d

Rei

nves

tmen

t A

llo

wan

ce.

Pio

nee

r S

tatu

s an

d

Inves

tmen

t T

ax A

llo

wan

ce

and

Rei

nves

tmen

t

All

ow

ance

.

Pio

nee

r S

tatu

s an

d

Inves

tmen

t T

ax A

llo

wan

ce

and

Rei

nves

tmen

t

All

ow

ance

.

Pio

nee

r S

tatu

s an

d I

nves

tmen

t

Tax

All

ow

ance

an

d

Rei

nves

tmen

t A

llo

wan

ce.

Ince

nti

ves

fo

r h

igh

tec

h

ind

ust

ries

Ince

nti

ves

fo

r h

igh

tec

h

ind

ust

ries

Ince

nti

ves

fo

r h

igh

tec

h

ind

ust

ries

Ince

nti

ves

fo

r h

igh

tec

h

ind

ust

ries

Lo

cal

peo

ple

(15

-30

yea

rs o

ld)

65

0 0

00

peo

ple

s 3

50

00

0 p

eop

les

65

0 0

00

peo

ple

s 1

50

0 0

00

peo

ple

s

Wa

ste

wa

ter

ma

na

gem

ent

Ku

alit

i A

lam

Sd

n B

hd

, B

ukit

Nen

as, N

eger

i S

emb

ilan

Ind

ah W

ater

Kon

sort

ium

Ku

alit

i A

lam

Sd

n B

hd

,

Bu

kit

Nen

as, N

eger

i

Sem

bil

an

Ind

ah W

ater

Kon

sort

ium

Ku

alit

i A

lam

Sd

n B

hd

, B

ukit

Nen

as, N

eger

i S

emb

ilan

Ind

ah W

ater

Kon

sort

ium

Ku

alit

i A

lam

Sd

n B

hd

, B

ukit

Nen

as, N

eger

i S

emb

ilan

Ku

alit

i A

lam

Sd

n B

hd

Sel

ecti

on

:

Ker

teh

In

du

stri

al

Est

ate

40

Ta

ble

4 :

Wei

gh

ted

ma

rk

s a

nd

ex

pla

na

tio

n o

n t

he

pla

nt

site

lo

cati

on

fa

cto

rs

Fa

cto

rs:

7 –

10

Ma

rks

4 –

6 M

ark

s 0

– 3

Mark

s

Su

pp

ly o

f ra

w m

ate

rial

•

Ab

le t

o o

bta

in l

arge

sup

ply

lo

call

y

thu

s sa

vin

g o

n i

mp

ort

co

st.

•

Hav

ing l

on

g p

ipel

ine

net

work

s fo

r th

e tr

ansp

ort

atio

n o

f ra

w m

ater

ials

.

•

So

urc

e o

f ra

w m

ater

ials

fro

m

nei

ghb

ou

rin

g s

tate

s o

r co

untr

ies

wit

h t

he

dis

tance

not

exce

edin

g

80

km

.

•

Use

s a

pip

elin

e sy

stem

as

wel

l.

•

Un

able

to

obta

in r

aw m

ater

ial

fro

m c

lose

so

urc

es w

ith

th

e d

ista

nce

exce

edin

g 8

0k

m.

•

Fo

rced

to

im

po

rt f

rom

fo

reig

n

cou

ntr

ies

•

Use

a p

ipel

ine

syst

em a

s w

ell.

Pri

ce a

nd

are

a o

f la

nd

•

Lan

d a

rea

ex

ceed

ing 6

0 h

ecta

res

•

Pri

ce o

f la

nd

bel

ow

RM

20 p

er m

2

•

Lan

d a

rea

bel

ow

60

hec

tare

s

•

Pri

ce o

f la

nd

mo

re t

han

RM

20

p

er m

2

•

Lan

d a

rea

bel

ow

40

hec

tare

s

•

Pri

ce o

f la

nd

ex

ceed

ing R

M3

0 p

er

m2

Lo

cal

Go

ver

nm

ent

Ince

nti

ves

•

Ince

nti

ves

fro

m t

he

Loca

l O

rgan

izat

ion o

f C

oun

try

Dev

elop

men

t

•

Ince

nti

ves

fro

m s

pec

ial

com

pan

y

•

Ince

nti

ves

fro

m t

he

Loca

l O

rgan

izat

ion o

f C

oun

try

Dev

elop

men

t.

•

No

in

cen

tives

fro

m t

he

Lo

cal

Org

aniz

atio

n o

f C

oun

try

Dev

elop

men

t.

Tra

nsp

ort

ati

on

•

Co

mp

lete

n

etw

ork

an

d

wel

l m

ain

tain

ed h

igh

way

s, ex

pre

ssw

ays

and

road

s.

•

Inte

rnat

ion

al

Air

port

fa

cili

ties

ac

cess

to

th

e m

ain

lo

cati

ons

aro

un

d

the

worl

d.

•

Lo

cati

on

nea

r to

inte

rnat

ion

al p

ort

w

ith

im

po

rt a

nd

exp

ort

act

ivit

ies.

•

Rel

iab

le

rail

way

li

nes

to

re

mo

te

area

s n

ot

acce

ssib

le b

y r

oad

s.

•

Go

od

fed

eral

ro

ad a

nd

hig

hw

ay

syst

ems

•

Lim

ited

rai

lway

syst

em a

cces

s

•

Mo

re d

ista

nt

fro

m t

he

port

s

•

Air

port

fac

ilit

ies

wh

ich

may

no

t h

ave

inte

rnat

ion

al f

ligh

t fa

cili

ties

– o

nly

pro

vid

ing

do

mes

tic

flig

hts

.

•

Aver

age

road

syst

ems

•

No

hig

hw

ay o

r ex

pre

ssw

ay

syst

em i

n c

lose

pro

xim

ity.

•

No

rai

lway

syst

em.

•

Ver

y d

ista

nt

fro

m t

he

po

rts

or

har

bors

.

•

Dis

tan

t fr

om

th

e nea

rest

air

po

rt –

m

ore

th

an 1

00

km

aw

ay.

Table 5 : Weight Matrix On Site Location

Criteria Kerteh Gebeng Teluk

Kalong Pasir Gudang

Supply of raw material 6 6 7 3

Price and area of land 7 6 7 3

Local government incentives 8 8 8 8

Transportation 9 7 8 7

Workers supply 6 5 6 8

Utilities, water and electricity 8 6 7 7

Type of industrial and its

location

8

8

6

6

Waste water disposable 8 8 8 7

Total 60/80 54/80 57/80 49/80

75.00% 67.5% 71.25% 61.25%

2.2.10 Concluding Remark

Based on the matrix comparison made, Kerteh Industrial Estate has been chosen as

the site for the PET plant. The location of Kerteh Industrial Estate is highly strategic

compared to others where the reason is focused on the nature and the requirements of the

plant ;

• Kerteh industrial estate is situates at east coast of peninsular Malaysia and it is

only 9 km from Paka and 7 km from Kerteh.

• Low land prices compared to other location, which is at RM 1.94 – 60.26 per

metre square.

• Since this location if near the Kerteh Port, Kuala Terengganu port, and Kemaman

port, any trade involving the import and export of products and, if necessary, raw

materials can be achieved with relative ease

42

• Attractives incentives given by the Malaysia government and local government

which is :

� Infrastructure Allowance.

� Five-year exemption on import duty.

� 5 % discount on monthly electrical bills for first 2 years.

� 25-38 % exemption on daily water cost for 4545 m3 of water for 2 years

� Pioneer Status and Investment Tax Allowance and Reinvestment Allowance.

� 85% tax exemption on gross profit

• Constant supply of utilities such as cooling water, power supply and waste

management.

� Power supply : Tasik Kenyir Hydroelectric Dam , IPP YTL (600 MW) , IPP

YTL (600 MW), Paka Power plant (900 MW) and CUF Kertih

� Water supply : Bukit Sah ,Sungai Cherol ,Sungai Kemasik , and CUF Kerteh

� Waste management: Kualiti Alam Sdn Bhd Bukit Nenas, Negeri Sembilan and

Indah Water Konsortium

• Excellent transportation link by railway, road and airpot. Kerteh is connected to

Kuala Terengganu, Gebeng and Kuantan via main road and also railway.

Good pipeline connection between Gebeng, Kuantan, and Kerteh. Transportation

of raw material had been eased by the connection of pipeline between these two

petrochemical industrial plants. A good network of pipe racks is crucial as it creates for a

cheaper and efficient method in transporting chemicals from designated plants to the port. In

addition, a Centralized Utility Facilities (CUF) is also offering its services to plant owners in

Kerteh to provide the supply of electricity, industrial gases and utilities such as steam and

pretreated water.

43

2.3 Physical and Chemical Properties

2.3.1 Polyethylene Terephthalate (PET)

Molecular Structure :

Table 6 : PET Properties

2.3.2 Ethylene Glycol (EG)


Table 7 : EG Properties

Properties Values

Formula (C10H8O4)n

Molecular weight Depends on n number

Density 1.4 g/cm3

Melting point 260 °C

Boiling Point ~930 °C

Colour Colourless

Physical state Solid

Properties Values

Formula C2H6O2

Molecular weight 62.1

Density 1.11 g/cm3

Melting point -13 °C

Boiling Point 198 °C

Colour Clear liquid

Physical state Liquid

44

2.3.3 Diethyl Glycol (DEG)


Table 8 : DEG Properties

2.3.4 bis-hydroxyethyl terephthalate (BHET)


Table 9 : BHET Properties

Properties Values

Formula C4H10O3


Density 1.12 g/cm3

Melting point -10.45 °C


Colour Colourless


Properties Values

Formula C12H14O6


Density 1.34 g/cm3


Boiling Point 409.9 °C

Colour Colourless


45

2.3.5 Terephthalic Acid (TPA)


Table 10 : TPA Properties

2.3.6 Water

Molecular Structure : H – O – H

Table 11 : Water Properties

Properties Values

Formula C8H6O4


Density 1.52 g/cm3


Boiling Point sublimes

Colour White Crystal Powder

Physical state Solid

Properties Values

Formula H2O


Density 1.00 g/cm3

Melting point 0 °C


Colour Colourless


46

2.4 Feedstock Supply

2.4.1 Supplier Profile

OPTIMAL GLYCOLS (MALAYSIA) SD� BHD

The Company was established in July 1998 to develop a world class integrated

petrochemical facility in Kertih, Terengganu, Malaysia. Centered within the PETRONAS

Petroleum Industry Complex, Malaysia’s most sophisticated and advanced petrochemical

facility, the OPTIMAL GLYCOLS (MALAYSIA) SDN BHD is located 3 km from Pekan

Paka and 10 km from Kerteh.

OPTIMAL GLYCOLS (MALAYSIA) SDN BHD produces three main products ie.

Mono-Ethylene Glycol (MEG), Di-Ethylene Glycol (DEG) and Re-Distilled Ethylene Oxide

(RDO), using world-renowned EOG METEOR™ Technology from Dow, the most advanced,

efficient and cost competitive technology for the production of MEG, DEG and high purity

EO for derivatives.

Both, MEG (the largest volume product manufactured by OPTIMAL GLYCOLS) and

DEG are sold within Malaysia and to various countries throughout the Asia Pacific region.

OPTIMAL Glycols (M) Sdn Bhd is a wholly owned subsidiary of Petronas.

*NOTE: kTa: Kilo Metric Ton Per Annum (1000 MTY)

Products & Production Capacity of OPTIMAL GLYCOLS (M) SD� BHD:

Products kTa

Mono-Ethylene Glycol (MEG) 365

Di-Ethylene Glycol (DEG) 20

Re-Distilled Ethylene Oxide (RDO) 140

47

BP Amoco SD� BHD

The purified terephthalic acid (PTA) plant is located in the State of Pahang on the east

coast of the Malaysia peninsula, 25 km from Kuantan town. This BP wholly owned unit

began production in 1996 with an annual PTA capacity of 600,000 tons. Shipments are made

by truck, bulk containers, and FIBC bags.

The Kuantan plant employs over 270 full-time residents and 150 contractors.

Commissioned in 1996, the plant had received ISO 9002 certification in 1998 and ISO 14001

in 2001. The site had achieved many awards including the 1999 National Occupational Safety

& Health Award, the Prime Minister Hibiscus Award 2000/2001 for Exceptional

Achievement in Environmental Performance, National OSH Award 2001 for Transportation,

Logistics & Communications.

48

CHAPTER 3 : PRELEMI�ARY HAZARD A�ALYSIS

3.1 Safety Issues and Preliminary Hazard Analysis

Development of a complete plant design involves consideration of many different

topics .The overall picture of designing involves extensive study of engineering including the

most important parameter beside economic is the safety.

Chemical handling, processing and storing consist of many safety issues. The hazard

may simply come from storage of the chemicals and towards the reaction of the chemicals

itself. Hazards existed in some chemical because of its natural behavior to explode or react

dynamically with or without any external factors. Potential hazard will depend on inherent

toxicity of materials and also inherent toxicity of the materials frequency and duration of any

exposure .It is essential for designer to aware of these hazards and develop a design that will

minimize the potential hazards as minimum as possible.

This chapter will emphasize the important of Preliminary Hazard Analysis which

include identification and assessment of hazards and general safety procedure. Some of the

topic that will be included in this chapter are particular hazard for each chemical and law

requirement in Malaysia regarding set up a process plant in Malaysia.

3.2 Identification of Material and Chemical Hazard

The chemicals that are used in our process are listed as below:

Feed • Terephthalic acid

• Ethylene Glycol

Product • BHET

• PET

Byproducts • DEG

• AA

Catalyst • Antimony Trioxide

Fro

m a

ll o

f m

ater

ial

and

ch

emic

al i

nv

olv

ed i

n t

he

pro

du

ctio

n,

cert

ain

cri

tica

l fa

cto

rs m

ust

be

anal

yze

d f

rom

eac

h M

ater

ial

Saf

ety D

ata

Sh

eets

(M

SD

S)

as i

n t

he

Tab

le 1

4 ;

Ma

teri

al

Hea

lth

Aff

ect

Fir

e a

nd

Ex

plo

sion

C

orr

osi

vit

y

Sta

bil

ity

an

d

Rea

ctiv

ity

T

ox

icit

y

TP

A

Haz

ard

ou

s in

cas

e o

f sk

in

con

tact

(ir

rita

nt)

, o

f ey

e

con

tact

(ir

rita

nt)

, o

f

inges

tio

n,

of

inh

alat

ion

(lu

ng i

rrit

ant)

. R

epea

ted

or

pro

lon

ged

ex

po

sure

to

th

e

sub

stan

ce c

an p

rod

uce

targ

et o

rgan

s d

amag

e

May

be

flam

mab

le i

n

hig

h t

emp

erat

ure

N

ot

Av

aila

ble

N

ot

Av

aila

ble

Th

e su

bst

ance

is

tox

ic t

o b

loo

d,

kid

ney

s, l

iver

, b

lad

der

, b

rain

,

card

iov

ascu

lar

syst

em,

eyes

,

Nu

trit

ion

al a

nd

Gro

ss

Met

abo

lic,

ear

s, n

ose

/sin

use

s,

thro

at

Eth

yle

ne

Gly

col

Haz

ard

ou

s in

cas

e o

f

inges

tio

n.

Sli

gh

tly

haz

ard

ou

s in

cas

e o

f sk

in

con

tact

(ir

rita

nt,

per

mea

tor)

, o

f ey

e co

nta

ct

(irr

itan

t),

of

inh

alat

ion

. S

ever

e o

ver

-

exp

osu

re c

an r

esu

lt i

n

May

be

flam

mab

le i

n

hig

h t

emp

erat

ure

No

n-c

orr

osi

ve

in p

rese

nce

of

gla

ss

Inst

abil

ity w

hen

ex

cess

hea

t an

d i

nco

mp

atib

le

mat

eria

ls.

Rea

ctiv

ity

spec

ial

rem

ark

s:

Hyg

rosc

op

ic.

Ab

sorb

s

mo

istu

re f

rom

th

e ai

r.

Av

oid

co

nta

min

atio

n

wit

h m

ater

ials

wit

h

Ch

ron

ic e

ffec

ts:M

uta

gen

ic f

or

mam

mal

ian

so

mat

ic c

ells

. N

on

-

mu

tagen

ic f

or

bac

teri

a an

d/o

r

yea

st.

May

cau

se d

amag

e to

th

e

foll

ow

ing o

rgan

s: k

idn

eys,

liv

er,

cen

tral

ner

vo

us

syst

em

(CN

S).

50

dea

th.

hyd

rox

yl

com

po

un

ds.

Als

o i

nco

mp

atib

le

wit

h a

lip

hat

ic a

min

es,

iso

cyan

ates

,

chlo

rosu

lfo

nic

aci

d,

and

ole

um

PE

T

Irri

tati

ng t

o e

yes

,

resp

irat

ory

syst

em a

nd

sk

in

N/A

n

/a

No

fla

h p

oin

t d

ata

bu

t

avo

id t

emp

erat

ure

abo

ve

23

5 °

An

tim

on

y

Tri

ox

ide

Haz

ard

ou

s in

cas

e o

f sk

in

con

tact

(ir

rita

nt,

sen

siti

zer)

,

of

eye

con

tact

(ir

rita

nt)

, o

f

inges

tio

n,

of

inh

alat

ion

No

n-f

lam

mab

le.R

isk

of

exp

losi

on

wh

en

pre

sen

ce o

f st

atic

dis

char

ge

No

n c

orr

osi

ve

in p

rese

nce

of

gla

ss

Sta

ble

carc

ino

gen

ic e

ffec

ts:

Cla

ssif

ied

A2

(S

usp

ecte

d f

or

hu

man

.) b

y

AC

GIH

. C

ause

s d

amag

e to

th

e

foll

ow

ing o

rgan

s: l

un

gs,

mu

cou

s m

emb

ran

es.

Ta

ble

14

: M

SD

S f

or

Sel

ecte

d C

hem

ica

l

51

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

Red

uce

Inv

ento

ries

Rea

cto

r •

Ov

er p

ress

uri

zati

on

du

e to

vap

ori

zati

on

of

liq

uid

bec

ause

of

hig

h e

ner

gy r

elea

se.

•

Ov

erh

eate

d c

on

dit

ion

sin

ce t

he

rem

ov

al o

f

hea

t p

rod

uce

d i

s le

ss t

han

its

co

oli

ng r

ate,

wh

ere

pre

ssu

re w

ill

incr

ease

as

tem

per

atu

re

chan

ge.

•

Rat

e o

f te

mp

erat

ure

ris

e w

ill

be

fast

er o

nce

hea

t gen

erat

ion

ex

ceed

s th

e av

aila

ble

co

oli

ng

cap

acit

y.

•

Ch

oo

se c

on

tin

uo

us

or

sem

i b

atch

op

erat

ion

sin

ce b

atch

op

erat

ion

req

uir

es l

arg

e in

ven

tory

saf

ety i

nce

nti

ve.

•

Ov

erp

ress

ure

rel

ief

pro

tect

ion

su

ch a

s ru

ptu

re d

isk

,

pre

ssu

re s

afet

y v

alv

e, o

r co

mb

inat

ion

of

the

two

is

nee

ded

fo

r th

e re

acto

r.

•

Pro

per

pro

cess

co

ntr

ol

syst

em t

o a

vo

id o

ver

hea

ted

an

d

ov

er p

ress

uri

zati

on

co

nd

itio

ns

at t

he

reac

tor.

•

Fo

r re

acto

r w

ith

ru

naw

ay r

eact

ion

, th

e se

t p

ress

ure

of

the

safe

ty v

alv

e o

r ru

ptu

re d

isk

sh

ou

ld b

e cl

ose

to t

he

no

rmal

op

erat

ing p

ress

ure

as

po

ssib

le.

Dis

till

atio

n

•

Hig

h p

ress

ure

may

cau

se f

loo

din

g.

•

Lar

ge

inv

ento

ries

of

bo

ilin

g l

iqu

id,

som

etim

es u

nd

er p

ress

ure

, in

th

e d

isti

llat

ion

colu

mn

bo

th i

n t

he

bas

e an

d h

eld

up

.

•

Sel

ect

suit

able

seq

uen

ce t

hat

ten

ds

to m

inim

ize

the

flo

wra

te o

f n

on

key

co

mp

on

ents

.

•

Use

su

itab

le c

olu

mn

to

red

uce

th

e in

ven

tory

as

wel

l as

po

ten

tial

lea

kag

e p

rob

lem

.

•

Ov

erp

ress

ure

rel

ief

syst

em i

s n

eed

ed.

52

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

Hea

t

Tra

nsf

er

Op

erat

ion

•

Co

mm

on

saf

ety p

rob

lem

s in

clu

de

tub

e

rup

ture

, le

akin

g,

fou

lin

g,

tub

e v

ibra

tio

n,

po

lym

eriz

atio

n,

and

so

lid

ific

atio

n.

•

Fai

lure

s in

hea

t ex

chan

ger

s re

sult

in

pre

ssu

re

chan

ges

an

d c

on

tam

inat

ion

of

the

hea

t

tran

sfer

, fl

uid

or

pro

cess

flu

id.

•

Fla

mm

able

mat

eria

ls n

eed

s to

be

sub

stit

ute

wit

h l

ess

or

no

n-f

lam

mab

le m

ater

ials

.

•

Les

s h

azar

do

us

refr

iger

ant

flu

id u

sed

at

low

pre

ssure

op

erat

ion

may

lea

d t

o m

ajo

r h

azar

d, b

ut

it i

s al

low

able

wh

en t

he

pro

cess

is

at h

igh

er p

ress

ure

.

•

Do

ub

le t

ub

e sh

eets

are

rec

om

men

ded

fo

r h

igh

ly t

ox

ic

mat

eria

ls.

•

Ov

erp

ress

ure

rel

ief

is n

eed

ed f

or

pro

tect

ion

of

hea

t

exch

ang

ers

agai

nst

eff

ect

of

tub

e ru

ptu

re

Ch

em

ica

l R

eact

ion

•

Wh

en m

ore

haz

ard

ou

s co

mp

on

ents

in

vo

lve

in c

hem

ical

rea

ctio

n,

mo

re h

azar

do

us

con

dit

ion

(e.

g.

exp

losi

on

, ac

cid

ent

etc)

may

occ

ur.

•

Sel

ect

pro

cess

ro

ute

th

at i

nv

olv

es l

ess

haz

ard

ou

s

chem

ical

s.

•

If s

ub

stit

uti

on

is

no

t p

oss

ible

, is

ola

tio

n o

f th

e pro

cess

fro

m t

he

wo

rker

s is

nec

essa

ry.

Ch

em

ica

l S

tora

ge

•

Ch

emic

al l

eak

age

fro

m s

tora

ge

tan

k c

an l

ead

to v

apo

r cl

ou

d a

nd

to

xic

clo

ud

.

•

Imp

rop

er c

hem

ical

sto

rage

and

flo

w c

on

tro

l

may

lea

d t

o t

he

po

ssib

ilit

ies

of

exp

losi

on

of

the

sto

rage

equ

ipm

ents

sin

ce m

ost

ch

emic

als

bei

ng s

tore

d a

re f

lam

mab

le.

•

Sto

rage

equ

ipm

ents

nee

d t

o b

e at

a l

ow

tem

per

atu

re,

wel

l v

enti

late

d a

rea,

un

der

an

atm

osp

her

e o

f d

ry

nit

rogen

, an

d a

way

fro

m s

ou

rces

of

fire

haz

ard

.

•

Usa

ge

of

clo

sed

sp

her

ical

or

cyli

nd

rica

l ta

nk

s to

pre

ven

t th

e es

cap

es o

f v

ola

tile

s an

d m

inim

ize

con

tam

inat

ion

.

53

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

•

Ch

emic

als

that

lea

k c

an f

low

to

ele

ctri

cal

com

po

nen

t, w

hic

h i

s a

sou

rce

of

ign

itio

n t

hat

may

lea

d t

o e

xp

losi

on

.

•

Sto

rage

tan

k m

ay e

asil

y c

orr

od

e si

nce

th

e

chem

ical

s b

ein

g s

tore

d a

re m

ost

ly c

orr

osi

ve.

•

To

mai

nta

in t

he

pre

ssu

re o

f st

ora

ge

tan

k, p

ress

ure

safe

ty v

alv

e sh

ou

ld b

e in

stal

led

on

top

of

it.

Vap

ors

that

sh

ou

ld b

e v

ente

d f

rom

th

e ta

nk

mu

st b

e se

nt

to t

he

inci

ner

ato

r in

stea

d o

f at

mo

sph

ere.

•

Ven

t sh

ou

ld b

e p

osi

tio

ned

so

th

at t

he

ou

tlet

s ca

use

th

e

leas

t p

oss

ible

co

nta

min

atio

n t

o t

he

wo

rkin

g

atm

osp

her

e o

r an

y n

eigh

bo

uri

ng l

oca

tio

n.

•

Eq

uip

men

t fo

r st

ora

ge

tan

k n

eed

to

be

mad

e fr

om

gla

ss, p

oly

eth

yle

ne,

po

lyp

rop

yle

ne,

or

stai

nle

ss s

teel

.

Mat

eria

l o

f C

on

stru

ctio

n

•

Usa

ge

of

po

or

mat

eria

ls m

ay l

ead

to

lea

kag

e,

rup

ture

, co

rro

sio

n,

or

exp

losi

on

.

•

Usa

ge

of

carb

on

ste

el c

an l

ead

to

co

rro

sio

n

wh

en c

orr

osi

ve

com

po

nen

ts f

low

th

rou

gh

it.

•

Hig

h

pre

ssu

re

pro

cess

w

ith

in

ves

sels

an

d

colu

mn

s m

ay c

ause

cra

ckin

g.

•

Ele

ctri

cal

com

po

nen

ts

may

ca

use

a

spar

k

that

can

lea

d t

o e

xp

losi

on

if

any l

eak

age

of

flam

mab

le c

hem

ical

occ

urs

.

•

Sta

inle

ss s

teel

is

reco

mm

end

ed f

or

pro

cess

str

eam

to

pre

ven

t co

rro

sio

n.

•

Th

e th

ick

nes

s o

f th

e eq

uip

men

t n

eed

to

b

e o

n-

spec

ific

atio

n.

•

Ele

ctri

cal

equ

ipm

ents

sh

ou

ld

be

spar

k

resi

stan

ce

to

avo

id i

nci

den

t an

d p

rop

erty

lo

ss.

•

Su

itab

le

mat

eria

ls

of

con

stru

ctio

n

incl

ud

e st

eel,

stai

nle

ss

stee

l,

and

al

um

inu

m.

Gal

van

ized

st

eel

and

pla

stic

s sh

ou

ld n

ot

be

use

d.

Tem

per

atu

re a

nd

Pre

ssu

re

•

Hig

h p

ress

ure

op

erat

ion

may

ca

use

ser

iou

s

leak

age

pro

ble

m.

•

Ap

pro

pri

ate

des

ign

, op

erat

ing,

and

max

imu

m p

ress

ure

and

tem

per

atu

re a

re n

eed

ed t

o e

nsu

re s

afe

pro

cess

es.

54

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

•

Po

ssib

le a

cces

s o

f ai

r lo

w p

ress

ure

op

erat

ion

,

wh

ich

may

cau

se f

lam

e o

r ex

plo

sio

n w

hen

reac

t w

ith

fla

mm

able

co

mp

on

ent.

•

Hig

h t

emp

erat

ure

can

lea

d t

o r

up

ture

of

tub

es

carr

yin

g

pro

cess

fl

uid

s an

d

po

ssib

le

exp

losi

on

s.

•

Pro

tect

ion

b

y

inst

rum

ent

is

imp

ort

ant

to

mai

nta

in

tem

per

atu

re

and

p

ress

ure

to

th

e n

orm

al

op

erat

ing

pre

ssu

re.

To

xic

olo

gy

and

H

ealt

h

Haz

ard

s

•

Mo

st

chem

ical

s in

th

e p

roce

ss

or

pro

du

ct

stre

ams

hav

e to

xic

ity a

mo

un

t if

in

ges

ted

or

inh

aled

.

•

Fre

qu

ent

exp

osu

re o

f th

e ch

emic

als

may

lea

d

to h

um

an m

uta

gen

ic.

•

Dir

ect

con

tact

m

ay

cau

se

corn

eal

inju

ries

,

sev

ere

eye

irri

tati

on

or

bu

rns

to t

he

eyes

.

•

Pro

per

PP

E s

ho

uld

be

use

d t

o a

vo

id a

ny d

irec

t co

nta

ct

and

in

hal

atio

n o

f th

e to

xic

ch

emic

al.

•

Pro

per

ch

emic

al

han

dli

ng

pro

ced

ure

w

ith

h

igh

sup

erv

isio

n f

rom

ex

per

t p

erso

nn

el i

s n

eed

ed t

o e

nsu

re

safe

pro

ced

ure

s o

f op

erat

ion

.

Fla

mm

abil

ity

•

Ex

plo

sio

n

may

o

ccu

r if

th

e ch

emic

als

in

reb

oil

er o

r h

eate

r ar

e o

ver

hea

ted

.

•

Sp

ark

ca

n

be

pro

du

ce

fro

m

too

ls

and

veh

icle

s d

uri

ng m

ain

ten

ance

op

erat

ion

.

•

Wh

en

flam

mab

le

chem

ical

le

aks

reac

h

elec

tric

al c

om

po

nen

ts,

exp

losi

on

may

occ

ur.

•

Pro

hib

ited

an

d e

lim

inat

e al

l sp

ark

s an

d i

gn

itio

n s

ou

rces

as

wel

l as

an

y

flam

e u

sag

e in

th

e p

lan

t ar

ea

(e.g

.

smo

kin

g).

•

Usa

ge

of

ho

t w

ork

per

mit

is

nee

ded

if

any f

lam

e o

r

spar

kin

g

equ

ipm

ent

is

bei

ng

use

d.

Lo

wer

ex

plo

siv

e

lim

it (

LE

L)

of

the

area

mu

st b

e at

saf

e le

vel

bef

ore

an

y

op

erat

ion

st

arts

, w

ith

su

per

vis

ion

w

hil

e it

is

in

55

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

pro

gre

ss.

En

vir

on

men

tal

Imp

act

•

Was

te w

ater

str

eam

fro

m t

he

pro

cess

pla

nt

can

be

haz

ard

ou

s if

no

t w

ell

trea

ted

bef

ore

bei

ng r

elea

sed

to

su

rro

un

din

g o

r ri

ver

.

•

Pro

per

was

te w

ater

tre

atm

ent

is n

eed

ed t

o r

edu

ce t

he

tox

icit

y o

f w

ater

an

d t

he

com

po

nen

ts r

elea

sed

.

Sit

tin

g a

nd

Saf

e L

oca

tio

n

•

Em

issi

on

of

tox

ic a

nd

haz

ard

ou

s ch

emic

als

into

th

e at

mo

sph

ere

can

af

fect

th

e p

lan

t

per

son

nel

an

d

the

com

mu

nit

y

of

nea

rest

resi

den

tial

are

as.

•

Hig

h

risk

o

f d

isas

ter

(e.g

. ea

rth

qu

ake,

flo

od

ing e

tc)

may

cau

se s

erio

us

pro

ble

m t

o

the

pla

nt

op

erat

ion

.

•

Co

nsi

der

saf

e li

vin

g c

on

dit

ion

s fo

r p

lan

t op

erat

ion a

s

wel

l as

th

e n

earb

y c

om

mu

nit

y.

•

Su

itab

le p

lan

t lo

cati

on

sh

ou

ld b

e fa

r fr

om

res

iden

tial

area

, w

ith

th

e av

aila

bil

ity o

f n

earb

y so

urc

es o

f ra

w

mat

eria

ls a

nd

oth

er f

acil

itie

s su

ch a

s tr

ansp

ort

atio

n a

nd

fire

sta

tio

n.

•

Pro

vid

e ac

cess

ibil

ity

for

fire

fi

gh

tin

g

in

case

o

f

emer

gen

cy i

nv

olv

ing f

lam

e an

d e

xp

losi

on

.

•

Pro

vid

e ad

equ

ate

loca

tio

ns

of

emer

gen

cy

exit

s fo

r

rap

id e

vac

uat

ion

an

d r

escu

e.

•

Lo

cate

in

-sit

u a

uto

mat

ic f

ire

det

ecti

on

an

d s

up

pre

ssio

n

syst

ems

com

po

nen

ts

for

effe

ctiv

e re

spo

nd

w

ith

min

imal

rel

ian

ce o

n p

lan

t p

erso

nn

el.

•

Eli

min

ate

ign

itio

n

sou

rces

fr

om

th

e v

icin

ity

of

the

mo

st

flam

mab

le

and

ex

plo

siv

e m

ater

ials

an

d

equ

ipm

ent.

56

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

•

Iso

late

th

e m

ost

haz

ard

ou

s m

ater

ials

an

d p

roce

sses

to

mai

nta

in s

pec

ial

pre

cau

tio

ns

in t

hes

e h

azar

do

us

area

s.

Th

e si

ze an

d ex

ten

t o

f an

y h

azar

do

us

area

m

ust

b

e

lim

ited

to e

nsu

re t

hat

the

pla

nt

is n

ot

at r

isk

fro

m a

ny

acci

den

t

•

Pro

vid

e p

assi

ve

bar

rier

s fo

r fi

re

con

tain

men

t an

d

exp

losi

on

re

sist

ance

, w

hic

h

sho

uld

ef

fect

ivel

y

lim

it

fire

or

exp

losi

on

pro

pag

atio

n a

nd

dam

age

even

in

the

abse

nce

of

acti

ve

det

ecti

on

an

d s

up

pre

ssio

n.

Pla

nt

Lay

ou

t •

Po

or

arra

ngem

ent

of

pro

cess

ing

area

s,

sto

rag

e ar

eas,

an

d

han

dli

ng

area

s fa

cili

ties

may

tro

ub

le t

he

pla

nt

op

erat

ion

, si

nce

mo

re

dam

age

and

acc

iden

ts w

ill

occ

ur.

•

Co

nsi

der

saf

e op

erat

ion

al s

equ

ence

in

th

e la

yo

ut

bas

ed

on

th

e fl

ow

of

mat

eria

ls,

un

it o

per

atio

ns,

sto

rage

and

futu

re e

xp

ansi

on

.

•

Sep

arat

e p

roce

ss

and

n

on

-pro

cess

ar

ea.

Fla

rin

g

and

sto

rag

e ar

ea s

ho

uld

be

loca

ted

far

fro

m p

roce

ss a

rea.

•

Ass

emb

ly

area

s m

ust

b

e p

rov

ided

in

ca

se

of

emer

gen

cy a

t b

oth

pro

cess

an

d n

on

-pro

cess

are

a.

•

Co

nsi

der

th

e p

lace

men

t o

f ra

w w

ater

tan

k n

ear

the

hig

h

po

ten

tial

of

flam

ing a

rea.

•

En

ou

gh

lig

hti

ng a

nd

co

lor

cod

ing f

or

reco

gn

itio

n o

f

haz

ard

ou

s an

d n

on

haz

ard

ou

s ar

eas.

57

Item

P

ote

nti

al

Ha

zard

s P

ote

nti

al

Mit

iga

tin

g M

ea

sure

s

Tra

nsp

ort

atio

n

•

Sp

illa

ge

of

tox

ic

chem

ical

s m

ay

cau

se

seri

ou

s in

juri

es w

hen

dir

ectl

y b

e in

co

nta

ct.

•

Vap

or

may

pas

s th

rou

gh

th

e co

nta

iner

’s c

ap

if i

t is

no

t p

rop

erly

sea

led

.

•

Wit

h i

mp

rop

er r

oad

syst

em,

the

occ

urr

ence

of

acci

den

ts i

s o

f h

igh

ris

k.

•

Em

plo

yee

s n

eed

to

w

ear

per

son

nel

p

rote

ctiv

e

equ

ipm

ent

for

pro

tect

ion

fr

om

to

xic

an

d

haz

ard

ou

s

chem

ical

s.

•

Co

nta

iner

s m

ust

be

seal

ed p

rop

erly

an

d c

lear

ly l

abel

ed

bef

ore

bei

ng t

ran

spo

rted

.

•

Pro

hib

it u

nau

tho

rize

d v

ehic

les

fro

m e

nte

rin

g p

roce

ss

area

.

•

Pip

ing

arra

ng

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15

: S

afe

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Mea

sure

s

3.3 Emergency Situation Procedure

Accidents could be happened regardless of time and place. There is a need to list the

emergency procedure guideline.

General Procedure

Some of the procedures that must be taken when the emergency situation happened in the

plant are :

i. Do not panic and stay alert.

ii. Assess the situation around your area.

iii. Wait for instructions from supervisor or shift manager.

Fire/Explosion/>atural Disaster

This procedure should be taken for fire , explosion or natural disaster are same.Basically ,the

procedures especially for the above situation are:

i. Raise the alarm.

ii. Immediately inform the supervisor or shift manager.

iii. Assess the situation.

iv. Wait and follow the instruction from them.

Hazardous Substance Discharge

If any hazardous substance discharge incident occurred, without taking any unnecessary

personal risk, the following procedure had to be followed:

i. Immediately inform the supervisor or shift manager

ii. Minimize substance discharge

iii. Identify substance and act accordingly

iv. Neutralize the substance discharge

v. Wait for the instructions from supervisor or shift manager

59

The following are the basic precaution for the two common hazardous substances:

1. Inflammable liquid

• Use only spark-proof materials

• Do not make any ignition

• Beware with electrical switchgear that can cause a spark.

2. Corrosive Liquid

• Use the safety clothes

• Check location and operation of safety shower or cold water supply

• Use breathing equipment if the substance emits toxic flames.

Instrument Protective System

Hazard not only comes from chemicals itself, it may come from the instrument use in the

process. Therefore there is a need to check the instrumentation protective system and should

be tested regularly to ensure it is in good condition. Some of the protective system is listed

below:

i. Air monitoring

ii. Leak detection system

iii. Emergency valves

iv. Labels and sign

v. Controlling leaks

3.4 Local Safety Regulations

Laws and regulations are major tools for protecting people and also environment

.Local safety and environmental regulations must be compiled with when developing new

plant, in order to ensure safe workplace and prevent accidents or any environmental pollution

that can adversely affect the whole plant operation as well as the surroundings. Listed are

several related acts and regulations for compliance:

60

Occupational Safety and Health Act (OSHA) 1994

OSHA was created with a purpose to reduce work-related injuries, illness and death and

incidentally, to cut resulting cost (lost wages and productivity, medical expenses, disability

compensation).

The following is the related act of OSHA for the process plant safety:-

• Factories and Machinery Act 1967

• Occupational Safety and Health (The Control of Industrial Major Accident

Hazards) Regulations 1996

• Occupational Safety and Health (Classification, Packaging, and Labeling of

Hazardous Chemicals) Regulations 1997

• Occupational Safety and Health (Use and Standards of Exposure of Chemicals

Hazardous to Health) Regulations 2000

Environmental Quality Act (EQA) 1974

Environment Quality Act 1974 has the objective for prevention, abatement and

control of pollution and enhancement of environment by restricting discharge of waste which

applies to the whole Malaysia. The act control pollution by licensing and approval for

existing operation, through prohibition of equipment and material, and Environmental Impact

Assessment (EIA) requirement.

61

Before starting any industry, EIA report has to be prepared to report the information

about the industry itself and the consequences to the environment, where it has to be

submitted to the Department of Environment of the state to be approved before license is

given. The following are the related act regarding to process plant industry:-

• Environmental Quality (Licensing) Regulations, 1977

• Environmental Quality (Clean Air) Regulations 1978

• Environmental Quality (Sewage and Industrial Effluents) Regulations 1979

• Environmental Quality (Prescribed Activities) Regulations 1986

• Environmental Quality (Prescribed Activities) (Environmental Impact

Assessment) Order 1987

• Environmental Quality (Scheduled Wastes) Regulations 1989

• Environmental Quality (Prescribed Premises) (Scheduled Treatment and

Disposal Facilities) Order 1989

• Environmental Quality (Prescribed Premises) (Scheduled Wastes Treatment

and Disposal Facilities) Regulations 1989

62

CHAPTER 4: CO�CEPTUAL DESIG� A�ALYSIS

4.1 Preliminary Reactor Optimization

4.1.1 Reactions Involved

There are three reaction paths involved in the process for the production of polyethylene

terephthalate (PET). The first path is esterification reaction, the second path is pre-

polycondensation reaction and the third path is final polycondensation reaction.

Esterification reaction:

C8H6O4 + 2 C2H6O2 ⇌ C12O6H14 + 2 H2O

Pre-polycondensation reaction:

nC12O6H14 ⇌ C2H5O(C10H8O4)nOH + (n-1)C2H6O2 n = 30

Final polycondensation reaction:

mC2H5O(C10H8O4)nOH ⇌ C2H5O(C10H8O4)n.mOH + (m-1)C2H6O2 m = 3.733

4.1.2 Esterification Reaction

In the esterification reaction, terephthalate acid (TPA), C8H6O4 is reacted with ethylene

glycol (EG), C2H6O2 producing monomer known as bis-(2-hydroxyethyl) terephthalate

(BHET), C12O6H14 and water, H2O. The reaction is reversible; therefore water formed during

the reaction has to be removed in order to convert the starting materials completely into the

monomer. A catalyst is not required in this reaction and conventionally no catalyst is

employed (Kathleen L. Trojan, 1999). Esterification is generally accepted as a third order

reaction, thus the acid behaves both as a reactant and a catalyst. The rate constant of

esterification was found to increase with pKa of the carboxylic acid (Faissal-Ali El-Toufaili,

2006).

63

Figure 10: Overall Esterification Reaction

The figure above describes the overall esterification reactions that occurred in the reactor.

Based on the figure, the limiting reactant is TPA and the excess reactant is EG. The amount

of EG that is use as feed in the process is 192.52 kmol/hr, however since the pre-

polycondensation and final polycondensation reaction produced EG as well, some of the EG

produced from the reactions will be recycle into the esterification reactor, making the

amount of feed into the first esterification reactor become 628.45 kmol/hr. The reaction

mixture in this reactor is a heterogeneous system in which solid, liquid and vapor phase are

jumbled together. Due to the solid TPA, a monomer in PET synthesis has very low solubility

in EG (Ju-Youl Kim, Hee-Young Kim & Yeong-Koo Yeo, 2001). A high operation

temperature of the esterification reactor is needed to dissolve the TPA in EG and to increase

the rate of reaction.

In the reaction system, it is assumed that the vapor pressure is contributed only by EG and

water because oligomer is not volatile, the vapor pressure of TPA and DEG are negligible,

and only EG vapor is recycled completely. All reactions proceed in liquid phase, and the

density of the reaction mixtures is assumed to be constant. Even though the reaction mixtures

are slurry with high viscosity, the assumption of perfect mixing is the reactor is applicable

since various mixing units are used in the actual plant to prevent loss due to imperfect mixing

(Ju-Youl Kim, Hee-Young Kim & Yeong-Koo Yeo, 2001).

ESTERIFICATION

REACTOR Mol flow rate (kmol/hr)

C8H6O4: 161.08

C2H6O2: 628.45

Mol flow rate (kmol/hr) C12O6H14: 158.02

H2O: 315.72

64

The reactor operates at 250ºC, at a pressure of about 265 kPa. Under these conditions and

with continuous removal of water by-product, it takes about 3 hours for the esterification

reaction to reach 85-95% conversion. The second esterification reactor operates at

temperature around 250ºC and at a pressure 250 kPa. The lower pressure reflects the fact that

in the second reactor, less volatile are being generated and the volatiles composition in

shifted from being rich in water to being rich in EG. After 2 hours, the esterification in the

second reactor is about 98% complete (S. M. Aharoni, 2002).

4.1.3 Polymerization Reactions

For the pre-polycondensation reaction, the BHET will further react to form the first polymer

of PET that has a degree of polymerization of 30 and EG. At this point, antimony trioxide is

added as catalyst. The reaction is also reversible; therefore the EG formed during the reaction

need to be removed to convert the monomer into the polymer. For the pre-polycondensation

reactor, the operating temperature is about 260ºC and the pressure is gradually decreased to

6.661 kPa where polyester with a degree of polymerization of around 30 is created. The pre-

polycondensation reactor is stirred tank reactors with unusual ratio of diameter or height to

provide large gas-liquid interface.

Figure 11: Pre-polycondensation Reaction

PRE-POLYCONDENSATION

REACTOR Mol flow rate (kmol/hr) C12O6H14: 158.02

Mol flow rate (kmol/hr) C2H5O(C10H8O4)30OH: 5.27

C2H6O2: 168.17

65

The final polycondensation reaction will proceed by expanding the polymer chain to produce

PET with a higher degree of polymerization, 112 (m x n = 112). This reaction is also

reversible and producing EG, therefore the EG formed need to be removed as well in order to

convert the reaction into the desired polymer. For this reactor, the operating condition is

280ºC with a pressure of 1.33 kPa. This reactor consist of horizontal vessels supplied by a

series of horizontal stirrers, which were optimized to provide a plug flow of the melt with

little back mixing in order to keep the residence time distribution narrow and to achieve

higher average polycondensation rate (Faissal-Ali El-Toufaili, 2006).

Figure 12: Final Polycondensation Reaction

Both of the reactors for polycondensation operate at a very high vacuum pressure to remove

the EG that is produced in the reaction. The final degree of polycondensation can be

controlled by adjusting vacuum, reaction temperature and average residence time.

Recycling of undesired product will increase the selectivity of the reaction. For example, in

the pre-polycondensation and polycondensation reactions, the EG that is produced can be

recycle into the esterification reactor and favor the reaction to produce more BHET. Another

advantage of recycling the by-product from polycondensation reaction is that the amount of

fresh feed (EG) that is needed to be feed into the reactor can be reduce and this will reduce

the cost of raw material.

Mol flow rate (kmol/hr) C2H5O(C10H8O4)112OH: 1.41

C2H6O2: 3.91

FINAL POLYCONDENSATION

REACTOR Mol flow rate (kmol/hr) C2H5O(C10H8O4)30OH:

5.27

66

4.2 Process Screening

4.2.1 Heuristic Approach for Separation System Synthesis

In conceptual design, other than the optimization of the reactor, separation sequence train is

also a major concern in designing a chemical processes.

i) Selection of separation techniques

ii) Sequencing of separation techniques

iii) Adapting operating conditions for integration and optimization

The objective of this separation train is to develop the overall flow sheet that indicates which

components need to be separated and where they are expected to leave the process. For this

process, two types of separators will be use depends on the inlet phase;

i) Distillation column – for single phase liquid mixture

ii) Two-Phase Separator – for two phase liquid-vapor mixture

4.2.2 Sequencing of Separators

For sequencing of separators in a separation system, the following heuristics were applied:

i) The most difficult separations will be done at the end of the process.

ii) Direct sequence is usually favored in this case. Sequences that remove the lightest

components alone one by one in column overheads should be favored.

iii) A component making up a large fraction of the feed should be removed first

Before entering the esterification reactor, the EG fed will be purify using distillation column

to remove the water content in the fresh feed. The same distillation column is use to purify

the EG recycled from the formation of by-product from polycondensation reactions.

Purification of EG fresh feed is important to overcome the accumulation of unwanted

impurities, in this case is water, which might affect the esterification reactions.

67

After entering the reactor, most of the products formed will be in two phase mixture. This

mixture can be separated by two-phase separator. The rules of thumb apply in heterogeneous

mixture separation:

i) Separation of heterogeneous mixture is easier than for homogeneous mixture

ii) Separation of heterogeneous mixture should be carried out before homogeneous

mixture separation

For this process, the use of separator is crucial especially in removing the water that has been

produced during the esterification reaction and removing EG in the polycondensation

reactions. This is to ensure that the reaction does not proceed to form the reactants since they

are reversible reactions. The vapor separated from the two-phase separator contains high

fraction of EG and water, thus both of this mixture need to be further separated using

distillation column. This vapor mixtures are cooled down to change the phase from vapor

phase to liquid phase in order to further separated using distillation column.

Besides using the distillation column for purifying of EG, it can also be used to separate

water from EG and at the same time, recycled back the EG into esterification reactor. The

advantages of using distillation column in separation of liquid mixtures:

i) Distillation columns offer the most economical way for liquid mixture separation,

as the operating cost is mainly on the utility (cooling water and steam) used within

the condenser and reboiler.

ii) Distillation are able to separate mixtures of wide range of liquid mixtures and

feed concentration, as other homogenous mixture separation are limited to feed

with low throughput and relatively pure.

iii) The ability of distillation to produce high-purity products, without involving any

extra components being introduced into the separation system like liquid-liquid

extractions.

68

4.2.3 Operating Conditions for Separators

The table below summarizes the operating conditions for separating unit in the process:

Unit Mixtures Operating Conditions

Distillation Column

Inlet = EG & Water

Outlet (liquid) = EG

Outlet (vapor) = Water

Reboiler

T = 207ºC P = 140 kPa

Condenser

T = 107.2ºC P = 130 kPa

Separator

(esterification)

Inlet = TPA, EG, Water & BHET

Outlet (liquid) = TPA, BHET, EG

Outlet (vapor) = Water & EG

Separator 1

T = 280ºC P = 141.7 kPa

Separator 2

T = 190º P = 131.7 kPa

Separator 3

T = 265ºC P = 101.3 kPa

Separator

(polycondensation)

Inlet = PET & EG

Outlet (liquid) = PET

Outlet (vapor) = EG

Separator 1

T = 280ºC P = 6.67 kPa

Separator 2

T = 270º P = 1.33 kPa

Table 16: Separators with Types of Mixtures and Operating Conditions

69

4.3 Economic Potential (EP)

4.3.1 Economy Analysis

It is crucial for plant designers and engineers to take economic feasibility into

consideration when planning a plant. Beside direct costs, there are also different types of cost

involved for the plant operation and establishment. The EPCIC (Engineering, Procurement,

Construction, Installation and Commissioning) has significant affect on plant economics.

Other factors that might affect economic are as shown below:

• Raw materials price fluctuation

• Company policies

• Governmental policies

Our economic analysis is based on assumptions stated below:

• The calculation made follows the Douglas’s approach method

• Prices for raw materials are valid till August 2010

• The interest rate for plant operation is 10% per annum

• Project life-cycle will be 20 years

• Plant operates at normal annual operation period which is 330 days

4.3.2 Total Capital Investment

Capital investment by is the total amount need to be invested in the early stages of

pant design.There are two parts for capital investment which are fixed capital investment and

working capital investment.

70

4.3.3 Fixed Capital Investment

Purchasing of necessary equipments plus the installation is crucial as it will be the

core investment that will determine the operatibility of the plant as well as piping installation,

land, instrumentation, services and the land where the plant is going to be established

Equipment Purchase Cost (RM)

Reactor 595,586.05

Separator 2,337,540.25

Compressor 535,223.00

Distillation column 7,032,410.00

Pump 801,888.17

Heater 1,266,312.00

Cooler 1,953,401.60

Mixer 2,421,233.00

Splitter 1,824,382.00

Total Equipment Cost 18,767,976.07

Source : MATCHES (www.matche.com)

Table 11 : Equipment Required and Estimated cost for PET Plant

71

From the fixed capital costs, we could split it into two costs which are direct cost and

indirect cost. The components of the direct and indirect cost are shown below:

COMPO�E�T ESTIMATIO� COST (RM)

Direct Cost

Total Equipments Costs 18,767,976.07

Equipment Installation (includes insulation and painting)

40% of total equipment cost 8,699,596.16

Piping System Installation 50% of total equipment cost 10,874,495.20

Instrumentation and Control 20% of total equipment cost 4,349,798.08

Electrical System Installation 15% of total equipment cost 3,262,348.56

Service facilities 50% of total equipment cost 10,874,495.20

Building, process and auxiliary

40% of total equipment cost 8,699,596.16

Land 6% of total equipment cost 1,304,939.42

Yard Improvement 12% of total equipment cost 2,609,878.85

Total 69,443,123.68

Indirect Costs

Engineering and supervision Construction expenses

10% of total direct cost

6,944,312.368

Legal expenses 10% of total direct cost 6,944,312.368

Contractors fee 5% of total direct cost 3,472,156.184

Contingencies 12% of total direct cost 8,333,17.842

Total 18194098.03

Fixed Capital Investment Direct Costs + Indirect Costs 87,637,221.71

Table 12 : Fixed Capital Investment for PET Production Plant

72

4.3.4 Working Capital Investment

Working capital represents costs necessary to operate the plant. Listed below are the

components of the working capital that need to be taken account.

1. Raw materials for one-month supply.

2. Finished products in stock and semi finished products.

3. Accounts receivable.

4. Cash on hand to meet the operating expenses.

5. Accounts payable and taxes payable

Typically, Douglas proposes that the estimated value of working capital investment is simply

15% of the fixed capital investment (III).

Working capital investment = 0.15 x fixed capital investment

= 0.15 x RM 87,637,221.71

= RM 13,145,583.26

4.3.5 Start Up Cost

Costs allocated for starting up the plant operation are start-up costs. Some of the examples of

start-up costs are process modifications, start-up labor and loss in production.

From Douglas method, the startup cost will be 10% out of fixed capital investment.

Start-up Costs = 0.10 x fixed capital investment

= 0.10 x RM 87,637,221.71

= RM 8,763,722.171

73

4.3.6 Total Capital Investment

The total for total capital investment is addition from fixed capital investment and working

capital. But we add up the start-up costs as added values.

Total capital investment = Fixed capital investment + Working capital investment

+ Start-up costs

= RM 87,637,221.71 + RM 13,145,583.26 + RM 8,763,722.171

= RM 97,715,527.14

4.3.7 Utilities

Plant uses both hot utility and cold utility. Both of the utilities tariff are take from

latest Tenaga Nasional Berhad as this industry falls under the category of industrial

consumer.

We assume that we will be using the high voltage industry tariff. Below shown the tariff for

high voltage industry:

Figure 9: Tariff for High Voltage Industries

74

UTILITIES USAGE TOTAL COST

Cold 2,065.6 kW/h RM549.45 /h (Peak period)

RM330.496 /h (Off-Peak Period)

Hot 3714 kW/h RM 965.64 /h (Peak period)

RM 594.24 /h (Off-peak period)

TOTAL RM 1515.09/h (Peak period)

RM 924.736 /h (Off- Peak period)

Table 13 : Plant Utilities

Assume Peak period 8AM-5PM

= RM1515.09 X 8 Hours

= RM12, 120.72

Off-Peak Period 7PM-8AM

= RM 924.736 X 16 Hours

= RM 14,795.776

Total for a day = RM 26,916.496

= RM 26916.496 X 330 days

= RM 8,882,443.68 /year

Economy Potential 1:

Economic Potential 1 (EP 1) = (Product value) – (Raw material cost)

Mass flow for main chemicals:

Ethylene Glycol (EG) = 11973.19 kg/hr

Terepthalic Acid (TPA) = 26760 kg/hr

PET = 30450.7 kg/hr

75

Pricing :

Substance Pricing (August 2010)

Ethylene Glycol $1006 / ton

Terepthalic Acid $895 / ton

PET $1 350 /ton

(Source: www.icis.com)

Calculations :

TPA =

= $718.39 /hr

EG =

= $ 2007/hr

PET =

= $34104.784/hr

Gross Profit

Profit = Product-Reactant

= $34104.784/hr – ($ 2007/hr + 718.39 /hr)

= $31379.394 /hr

= RM 97739.0804/hr

Gross Profit for a year (330 days)

76

Profit per day = RM97739.0804 /hr X 24 hours/Day

= RM 2,345,737.93/day

Profit per annum = RM 2,345,737.93/day X 330days/year

= RM 774,093,516.8 / year

77

4.4 Mass Balance by Manual Calculation & iCO� Simulation

Below is the mass balance performed by theoretical manual calculation compared to iCON

Simulation. Several assumptions have been made in order to have an accurate result.

a) Mass balance around esterification reactor 1 ( )

Manual

Component

Molecular

Weight

I�LET

OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

TPA 166.14 161.27 26793.39 8.06 1339.08

EG 62.08 628.45 39014.17 322.04 19992.24

BHET 254.26 0 0 153.21 38955.17

WATER 18.02 0 0 306.41 5521.50

Total

789.72 65808.01 789.72 65808.01

iCON

Component

Molecular

Weight

I�LET

OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

TPA 166.14 161.26 26790.78 8.06 1339.54

EG 62.08 628.59 39173.97 322.18 20156.39

BHET 254.26 0.33 53.66 153.53 39003.22

WATER 18.02 0.02 0.04 306.42 5520.28

Total

790.2 66018.45 790.2 66019.43

b) Mass balance around esterification reactor 2 ( )

78

Manual

Component

Molecular

Weight

I�LET OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

TPA 166.14 8.06 1339.08 3.23 536.63

EG 62.08 322.04 19992.24 312.37 19391.93

BHET 254.26 153.21 38955.17 158.05 40185.79

WATER 18.02 0 0 9.67 174.25

Total

483.31 60286.51 483.31 60286.51

iCON

Component

Molecular

Weight

I�LET OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

TPA 166.14 8.06 1339.08 3.23 536.63

EG 62.08 322.04 19992.24 312.37 19391.93

BHET 254.26 153.21 38955.17 158.05 40185.79

WATER 18.02 0 0 9.67 174.25

Total

483.31 60286.51 483.31 60288.61

c) Mass balance around pre-polycondensation reactor

( )

79

Manual

Component Molecular

Weight

I�LET OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

BHET 254.26 158.05 40185.79 0 0

PET30 5824.46 0 0 5.268 30683.26

EG 62.08 0 0 152.78 9484.58

Total

158.05 40189.79 158.05 40167.83

iCON

Component Molecular

Weight

I�LET OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

BHET 254.26 158.01 40176.72 0 0

PET30 5824.46 0 0 5.27 30690.95

EG 62.08 10.85 673.51 163.65 10159.41

Total

168.86 40850.21 168.92 40850.36

d) Mass balance around final polycondensation reactor

( )

Manual

Component Molecular

Weight

I�LET OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

PET30 5824.46 5.268 30683.26 0 0

PET112 21575.02 0 0 1.411 30442.3

EG 62.08 0 0 3.857 239.55

Total

5.268 30683.26 5.268 30681.74

80

iCON

Component Molecular

Weight

I�LET OUTLET

mol

(kmol/hr)

mass

(kg/hr)

mol

(kmol/hr)

mass

(kg/hr)

PET30 5824.46 5.27 30690.91 0 0

PET112 21575.02 0.001 18.45 1.41 30450.71

EG 62.08 0.05 3.10 3.91 242.45

Total

5.321 30712.46 5.32 30712.66

a) Mass balance around distillation column ( )

Man

ual

Co

mp

on

ent

Mo

lecu

lar

Wei

gh

t

I�L

ET

O

UT

LE

T T

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(V

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UT

LE

TT

OP

(D

) O

UT

LE

T B

OT

TO

M

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

EG

6

2.0

8

62

8

38

98

6.2

4

0

0

0

0

62

8

38

98

6.2

4

WA

TE

R

18

.02

3

15

.71

5

68

9.0

9

31

5.7

1

56

89

.09

0

0

0

0

To

tal

9

43

.71

4

46

75

.33

3

15

.71

5

68

9.0

9

0

0

62

8

38

98

6.2

4

iCO

N

Co

mp

on

ent

Mo

lecu

lar

Wei

gh

t

I�L

ET

O

UT

LE

T T

OP

(V

) O

UT

LE

TT

OP

(D

) O

UT

LE

T B

OT

TO

M

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

mo

l

(km

ol/

hr)

ma

ss

(kg

/hr)

TP

A

16

6.1

4

0.1

9

31

.57

0

0

0

0

0

.19

3

1.5

7

EG

6

2.0

8

62

8.4

5

39

01

4.1

8

0

0

0.7

8

48

.42

6

28

.45

3

90

14

.18

BH

ET

2

54

.26

0

.33

8

3.9

1

0

0

0

0

0.3

3

83

.91

WA

TE

R

18

.02

3

00

.91

5

42

2.4

0

30

0.1

2

54

08

.16

0

0

0

.02

0

.36

04

To

tal

9

29

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45

52

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3

00

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5

40

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8

48

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28

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3

91

30

.03

82

4

.4.1

Blo

ck D

iag

ram

fo

r P

rod

uct

ion

of

PE

T P

roce

ss

Fig

ure

13

: B

lock

Dia

gra

m o

f T

he

Pro

cess

CHAPTER 5 : HEAT I�TEGRATIO�

5.1 Pinch Analysis

Pinch analysis is a well establish synthesis and analysis tool for exchange of heat

within a network of heat exchangers. Some of its capabilities are:

i) Setting pre-design targets for utility consumption

ii) Setting pre-design target for the installed cost of heat exchanger network

iii) Designing heat exchanger network

iv) Optimizing the trade-off between energy costs and capital cost, optimizing the

selection of utility source

5.5.1 Pre-design Target for Utility Consumption

Problem Table Algorithm method is used to design heat cascade, composite curve and

grand composite curve. In problem table, the energy balance within the each segment of the

temperature interval connecting the hot and cold streams. The actual temperatures have to be

adjusted according to:

Cold stream = T + (∆Tmin/2)

Hot stream = T - (∆Tmin/2)

In this case, ∆Tmin = 10ºC. Below are the shifted temperature (TT*, TS*) for temperature

target (TT) and temperature supply (TS) together with the heat capacity.

Stream TT (ºC) TS (ºC) TT* (ºC) TS* (ºC) Cp (kJ/ºC.hr) H (kJ/hr)

H1 170 290 165 285 781.82 93818.4

H2 190 280 185 275 53959.49 4856354

C1 250 173.3 255 178.3 186103 14274100

C2 280 251.4 285 256.4 110576.9 3162499

C3 280 265 285 270 58248.9 873733.5 Table 17: Data from iCon Simulation

T

he

figu

re b

elo

w s

ho

ws

the

hea

t tr

ansf

er b

etw

een

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h i

nte

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of

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per

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re.

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ssio

n t

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use

d t

o c

alcu

late

th

e h

eat

tran

sfer

bet

wee

n

each

in

terv

al i

s:

∑∑

∆−

=i

ico

ldp

ihot

Pi

TF

CF

CQ

])

()

([

,,

T(º

C)

∆T

(ºC

) Σ

Cp

c -

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ot

∆H

(kJ

/hr)

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80

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ure

14

: H

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y M

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l C

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85

P

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in

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tem

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re i

nte

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T (

ºC)

Qh =

13

37

05

58

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28

5

∆H

= 1

68

04

40

27

5

11

69

01

19

∆H

= 5

70

42

2.5

27

0

11

11

96

96

∆H

= 7

59

36

4

2

56

.4

10

36

03

32

∆H

= -

76

63

7.8

25

5

10

43

69

70

∆H

= 9

19

53

18

18

5

12

41

65

2

∆

H =

12

41

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2

1

78

.3

0

∆

H =

-1

03

98

.2

1

65

Qc =

10

39

8.2

T (

ºC)

0

28

5

∆H

= 1

68

04

40

27

5

-16

80

44

0

∆

H =

57

04

22

.5

2

70

-22

50

86

2.5

∆H

= 7

59

36

4

2

56

.4

-30

10

22

6.5

∆H

= -

76

63

7.8

25

5

-29

33

58

8.7

∆H

= 9

19

53

18

18

5

-12

12

89

06

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∆

H =

12

41

65

2

1

78

.3

-13

37

05

58

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∆

H =

-1

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98

.2

1

65

-13

36

01

60

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Fig

ure

15

: P

rob

lem

ta

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Alg

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ma

nu

al

Ca

lcu

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Adju

st h

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ive

val

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d

86

T

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ual

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n w

as c

om

par

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sin

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spen

HX

-Net

20

06

so

ftw

are.

QC =

24

85

kca

l/h

r

(1.0

4x

10

4 k

J/h

r)

Qh

=

3.1

96x

10

6

kca

l/hr

(1.3

37

x1

07 k

J/h

r)

87

C

om

po

site

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y u

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ure

16

: C

om

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88

G

ran

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om

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site

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y u

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20

06

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ure

17

: G

ran

d C

om

po

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Cu

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gen

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ted

by

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en H

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00

6 s

oft

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re

89

H

eat

exch

anger

net

wo

rk g

ener

ated

by m

anu

al c

alcu

lati

on

To

tal

Ho

t U

tili

ty =

93

34

32

5.8

+ 3

16

24

99

+ 8

73

73

3.5

= 1

3,3

70

,55

8.3

kJ/

hr

To

tal

Co

ld U

tili

ty =

10

,39

8.2

06

kJ/

hr

∆H

(k

J/h

r)

T(º

C)

83

42

0.1

9

18

3.3

10

39

8.2

1

Cp

(k

J/h

r)

∆H

(k

J/h

r)

83

42

0.1

9

29

0

17

0

78

1.8

2

10

39

8.2

06

48

56

35

4

28

0

19

0

53

95

9.4

9

14

27

41

00

2

50

18

61

03

93

34

32

5.8

4

85

63

54

8

34

20

.19

31

62

49

9

28

0

25

1.4

4

11

05

76

.9

31

62

49

9

87

37

33

.5

28

0

26

5

58

24

8.9

87

37

33

.5

17

3.3

Fig

ure

18

: H

eat

Exch

an

ger

�et

wo

rk

17

4ºC

2

00

ºC

5.2 Difference in Heat Exchanger Duty Requirement Before and After Heat

Integration (HI)

i) Hot utility

Duty before HI = 18,310,332.5 kJ/hr

Duty after HI = 13,370,558.3kJ/hr

ii) Cold utility

Utility excluded in HI = 7,425,733.81 kJ/hr

Duty before HI = 7,425,733.81 + 4,950,172.4 = 12,375,906.21 kJ/hr

Duty after HI = 7,425,733.81 + 10,398.206 = 7,432,132.016 kJ/hr

Type of Utility Duty before HI

(kJ/hr) Duty after HI (kJ/hr) % Saving

Hot 18,310,332.5 13,370,558.3 26.98

Cold 4,950,172.4 10,398.206 39.95

Table 18 : Summary Of % Saving After Heat Integration

From the heat integration analysis table, the plant can reduce the amount of cold utility and

hot utility up to 29.95% and 26.98% respectively. Thus, it can be concluded that heat

integration in beneficial as it reduce the operating cost.

91

CHAPTER 6 : PROCESS DESCRIPTIO�

6.1 Process Description

Polyethylene Terephtalate (PET) is a type of thermoplastic polymer at which it is

produced by step-growth polycondensation polymerization under evolution of condensates

that is water during the esterification process and also ethylene glycol (EG) during the

polycondensation process.

Figure 19: Reaction flow of PET production.

92

6.2 Feed Raw Material

The first step in producing Polyethylene Terephtalate is the esterification process

whereby in this process, Terephthalic Acid (TPA) is reacted with Ethylene Glycol (EG) in a

direct esterification reaction, producing bis-(2-hydroxyethyl) terephthalate (BHET) and

water.

At the plant, the recycled Ethylene Glycol (EG) produced from the previous poly

condensation process are mixed with raw EG from supplier. Mixture of raw Ethylene Glycol

(EG) with the recycled one contained some impurities, thus they are fed to the distillation

column for the impurities to be removed first. Then purified Ethylene Glycol (EG) is fed to

another mixer to be mix with Terephtalate Acid (TPA) to form a paste at atm pressure and

room temperature. In the case of plant PET production, both raw reactants that is Ethylene

Glycol and Terephtalate Acid (TPA) are stored in two different storage facilities at which

Ethylene Glycol (EG) is stored in tank while Terephtalate Acid (TPA) is stored in the silos

since it is in powdered form compared to the Ethylene Glycol (EG) that initially is in liquid

form.

6.3 Reactions Involved

6.31 Esterification Process

As for the industrial production of PET, the ratio between feed Ethylene Glycol (EG)

to Terephtalate Acid (TPA) fed to the esterification reactor are in the range of 1.2:1 in order

to maximise the reaction between these two reactants since Terephtalate Acid (TPA) acts as

the limiting reactant in this reaction.

The mixtures of these two reactants are then being heated up to temperature of 250oC

and pressure of 265kPa in the first esterification reactor. The temperatures is further increased

in the second esterification reactor up to 265oC while the pressure is decreased to the atm

pressure since most of the water vapour formed from the eterification process has been

removed earlier in the first eserification reactor. This esterification reaction is reversible,

93

hence the water formed during the reaction has to be removed in order to convert the starting

materials completely into the monomer.

Figure 20 : Esterification process

Figure21: Series of esterification reactor

6.32 Separation Process

Water vapour that has been removed from the first reactor during the esterification

process is separated from the remaining unreacted Ethylene Glycol (EG) and Terephtalate

Acid (TPA) by using separator. The bottom product of this separator that mostly contains the

remaining Ethylene Glycol (EG) and Terephtalate Acid will further reacts to form BHET

monomer thus increase the total reaction conversion.

As shown in figure 6.3, for each of the rector, there is at least one separator to

separate the resulted water vapour produced from the esterification process. The top product

94

from these separators is fed to the Ehtylene Glycol (EG) recovery system at which Ethylene

Glycol (EG) will be recovered using distillation column.

There are two (2) flash tanks acted as separator attached to the output or the first

esterification reactor. These flash tanks operated to separate water vapour produced from the

esterification process from the mixtures. High input temperature to the flash tank causes

more water vapour to evaporates that induced some of the Ethylene Glycol (EG) to vaporize

as well. Thus the second flash tank meant to reduce the losses of Ethylene Glycol (EG) and to

increase degree of separation water vapour as well.

The bottom product of the second flash tank is then fed back to the second

esterification reactor. This at the same time could minimized the losses of Ethylene Glycol

(EG) from the system itself.

Figure 22: Ethylene Glycol recovery system

A distillation column involved in the Ethylene Glycol (EG) recovery system at which

all the recycled streams from top product of flash tanks connected with the reactor in the

esterification and polycondensation process are fed to the distillation column. These recycled

streams are cooled first by the cooler since most of the top product of the flash tanks are in

the form of gas phase thus by lowering the temperature, it could liquefied these gasses before

95

being fed into a mixer (M1) and then to the distillation column to separate between used

Ethylene Glycol and water vapour moisture.

The bottom product of this distillation column that contains minimum impurities mix

back with added raw Terepthalate Acid (TPA) for the continuous of PET process. The top

products of the distillation column that mostly contained water went to the water treatment

system for further treatment process before being released to nearby natural water system.

6.33 Purging system

Figure 23: Purging system

As for the purging system, it is crucial to have it as small amount from the

combination of two (2) streams that is the recycled system and raw input of Ethylene Glycol

(EG) will be purged into the Ethylene Glycol (EG) Recovery tank. The main reason for the

plant to have this purging system is to avoid any over accumulated of Ethylene Glycol (EG)

in the recycled stream that later will disturb the ratio of Ethylene Glycol (EG) to Terephtalate

Acid (TPA) used as feeds in the overall process.

96

6.34 Polycondensation Process

Previously, Ethylene Glycol (EG) and Terapthalate Acid (TPA) did not fully react in

the esterification process thus some acid end-groups from Terepthalate Acid (TPA) remain in

the prepolymer further react to form oligomer of PET.

These oligomers of PET and bis-(2-hydroxyethyl) terephthalate (BHET) will proceeds

to the next reactor to form PET with desired degree of polymerization (DP) in the

polycondensation process.

Unlike esterification process, polycondesation process of BHET to produce PET

requires the addition of catalyst to induce the rate of reaction in the step-growth

polycondensation. The catalyst most frequently employed in the polycondensation reaction is

a catalyst based on antimony such as antimony acetate or antimony trioxide.

The product (BHET) from this esterification process will acts as the monomer to

undergo to the next polycondensation process to form the PET. Monomer BHET is lead to

step-growth polymerization in the form of melt phase to polycondensation reactor. For the

purpose of polycondensation process, two(2) reactors are used to produced PET with desired

degree of polymerization (DP). In the first reactor, monomer react at high temperature of

280oC and vacuum pressure of 6 kPa to induce the removal of Ethylene Glycol (EG) formed

during the polycondensation process.

As for the second reactor (high polymerizer) the short polymer chains formed in the

previous reactor lengthened. In this second reactor , temperature is maintained while the

pressure is further reduced to 1.3kPa at vacuum condition to forced more Ethylene Glycol

(EG) removed out from the mixtures in the bubble forms since the mixtures are now become

more viscous.

97

Figure 24: Series of Polycondensation process.

The polycondensation processes proceeds until the desired PET product with certain

degree of polycondensation (DP) are produced. This degree of polymerization (DP) of the

final product of PET in the form of resins determines its physical and chemical properties at

which it signify the suitability of that resins to be used in the production of various grades

and types of products. As for the production of PET bottles, one need to produce degree of

polycondensation of PET resins between the ranges of 112-125.

Throughout the reactions of both esterification and polycondensation process, there

were some side reactions that occurred and produced some by-products together along with

the main products. During the evaporation of condensed byproducts, EG and W, is also

promoted by lower vacuum pressures, 6.666kPa in the first polycondensation reactor section

and 1.333 kPa in the second polycondensation reactor section, in order to favor the

lengthening of polymer chains. To overcome the high polymer viscosity, a high power to the

agitator of propeler and a high temperature, are required, but if the temperature is too high, i

leads to an undesired degradation due to side reactions, especially through the formation of

Aceteldehyde and Diethylene glycol (DEG) Then the product resulted from this second

polycondensation reactor should be in the form of viscous fluid with degree of

polymerization of n=112 that is required by bottle grade-PET.

Finally this polymer melt is generally filtered and then extruded into pellets.It is

extruded shortly after exiting the polycondensation stage and typically is extruded

immediately after exiting the polycondensation stage. Once the PET polyester is extruded it is

quenched, preferably in a water trough, to quickly decrease its temperature thus solidifying it.

98

The solidified PET polyester is formed into pellets or cut into chips for storage and handling

purposes

As for the formation of by-products during both of the process esterification and

polycondensation such as Aceteldehyde, it is resulted from degradation of BHET as the cause

of too high temperature in both of the process:

� +

BHET TPA Aceteldehyde

While for the formation of Diethylene Glycol (DEG), it is aby-products resulted from

reaction of BHET with unreacted Ethylene Glycol (EG) in the reactor.

+ OHCH2CH2OH � +

BHET EG TPA DEG

Other formation s of byproducts from the resulted side reactions are summarized as shown in

the figure below.

Figure 25: Reactions of functional group in stages of PET formation

99

CHAPTER 7 : CO�CLUSIO�S

Since the demand of Polyethylene Terephtalate (PET) is increasing throughout the

year, the production of PET through esterification and polycondensation process is viable and

economical as well. We could see that the rate of increasing for Polyethylene Tereplhtalate

demands is at constant and promising level each year thus provides a strong basis for one to

build a new plant producing this PET. This could be seen from the evaluation of Economic

Potential 1 (EP1) and Economic Potential 2 (EP2) that shown a high profit value since the

price of PET products is quite high as the reason of high demands from the consumers. Since

products made from Polyethylene Terephtalate is recyclable, it also could minimize the

emiisions of hazardous chemicals to the environments and at the same time could reduce the

consumption of oil petroleum products as well.

The main objective of this study that is to produced a flowsheet with a proper material

balance for a plant to produced Polyethylene Terephtalate (PET) in an industrial-scale

amount with all related preliminary crucial information to build a plant is achieved. This

includes the consideration of health, safety and environment (HSE) in the construction of the

plant so that its production is not only profitable but environment friendly as well. All

techniques and software related to construct the material and energy balance of the process

for producing this PET are stated in the report and each of the comparision values of

manually calculated and saftware calculated are at satisfied level since the error are at a low

value that not exceeded 0.05% as what has been practised by normal industrial practicioners.

All aspects of completing this project were partially completed and thus it is

preferrable for us to complete this project into the next semester.

100

REFERE�CES

• Hassan Niaz et. al, January 2009, PROCESS PLAN OF CONTINUOUS MELT-

PHASE POLYETHYLENE TEREPHTHALATE (PET) PRODUCTION PLANT

• S.M Aharoni, Industrial-Scale Production of Polysters, especially Polyethylene

Terephtalate (PET)

• Kevin C. Seavey, Step-Growth Polymerization Process Modelling and Product

Design

• Joonho Shin1,a, Yunghyo Leeb, Sunwon Park, 1999, Optimization of the pre-

polymerization step of polyethylene terephthalate (PET)

• Flavio Manenti, 2008, Integrated Multilevel Optimization in Large-Scale

Poly(Ethylene Terephthalate) Plants

• Yunqian Ma, 2005, Post Polymerization of Polyester for Fiber Formation

• Organic Chemical Process Industry

• JOHN SCHEIRS, 2003, Modern Polyesters: Chemistry and Technology of Polyesters

and Copolyesters

• Fatemeh Ahmadnian, 2008, Kinetic and Catalytic Studies of Polyethylene

Terephthalate Synthesis

• Robert H. Perry & Don W. Green, “Perry’s Chemical Engineering Handbook”, 7th

Edition, Volume 2, Mc-Graw Hill International Edition

• Pattalachinti, R.K., Modeling and Optimization of Continuous Melt-Phase

Polyethylene Terephthalate Process. Ohio University Master's Thesis, 1994

101

• Timothy J. Calmeyn, Optimization of Melt-Phase Polyethylene Terephthalate

Manufacturing Process. Ohio University Master's Thesis, 1995

• Faissal-Ali El-Toufaili, Catalytic and Mechanistic Studies of Polyethylene

Terephthalate Synthesis.Project Report, 2006

interim -2010final

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