detail energy audit report-draft-pradeep rice mill.docx

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Draft

Comprehensive Energy Audit Report

DULIELLA TEA

FACTORYPRADEEP RICE MILL

NeluwaSaliyapura

PreparedforPrepared for

INSTITUTE OF POST HARVESTING

and

By

Industrial Services Bureau (ISB)

ISB

for Sustainable Tomorrow

Comment [NPEJ2]: Delete

Comment [l1]: Deleted

Formatted:Font: (Default) Calibri, 11 pt, Scaps

Formatted:Font: (Default) Helvetica


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Comprehensive Energy Audit - Draf t Report Duliella Tea

FactoryPradeep Rice M il l

I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka II

JUNE FEBRUARY

20143

ABBREVIATIONS

CEB - Ceylon Electricity Board

hr - Hours

ISB - Industrial Services Bureau

SLSEA - Sri Lanka Sustainable Energy Authority

PADGO - Portfolio Approach to Distributed Generation Opportunities

kg - Kilograms

V - Voltage

kVA - Apparent power

kVAr - Reactive power

kW - Active power

kWh - Kilowatt hours

MT - Made Tea

GL - Green Leaf

SEEC - Specific Electrical Energy ConsumptionSDC - Specific Diesel Consumption

SLPGC - Specific LP Gas Consumption

HWG - Hot Water Generator

E - Electrical

T - Thermal

H - High

M - Medium

L - Low

I - Immediate (less than 6 months)

ST - Short Term (less than 1 year)

LT - Long Term (less than 3 years)

nos. - Numbers

M - Million


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka III


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka IV

ACKNOWLEDGEMENT

Industrial Services Bureau (ISB) wishes to express its gratitude to International Finance

CorporationInstitute of Post Harvest Technologies(IFCIPHT)and Sri Lanka Sustainable Energy

Authority (SLSEA) for giving itus an opportunity to conduct a comprehensive Energy Audit in

Duliella Tea Factory in NeluwaPradeep Rice Mill - Saliyapura.

Also, ISB would like to take this opportunity to thankMr. D.P.C Swarnasiri Additional Director,

Research & Technology Transfer- IPHT Mr. N. JayasooriyaMahesh Dissanayake, Associate

Operations Officer Mechanical Engineer IFCIPHT, Mr M. M. R. Pathmasiri, Director Energy

Management -SLSEA and Mr V. Ekanayake, Professional Engineer-SLSEA for their support in

organizing the energy audit. Our heartfelt gratitude to MrW.Jinadasa-Chairman, MrM. D.

Premachandra-ManagerManager, and the all staff of DuliellaTea FactoryPradeep Rice Mill for

their assistance and cooperation extended to the Consultants of ISB during the Energy Audit

carried out at their premises.

Our sincere appreciation also goes to the Consultants who took a great effort in completing the

assignment within the stipulated time frame. Though their names are not specifically mentioned

here,wehere, wewould also wish to thank all those who have helped us in numerous ways to

carry out this Energy Audit successfully.

ISB hopes that this report will help the management team of Duliella Tea FactoryPradeep Rice

Mill to have a greater awareness on the energy situation of the factory and to work towards

Energy Conservation & Management by implementing the recommendations of this report.

Industrial Services Bureau (ISB)

141, Kandy Road

Kurunegala, Sri Lanka

Tel : 0094 37 22 237 21 ~ 3

Fax : 0094 37 22 23562

Email: [email protected]

Web : www.isb.lk


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka V

EXECUTIVE SUMMERY

This report is an outcome of the energy audit conducted at Duliella tea factory from .To .

June 2013 covering both electrical and thermal energy use with the intention of improving the

energy efficiency and reducing the energy demand.

In general, DuliellaTea Factory maintains a fairly satisfactorylevel of energy efficiency. They

have already implemented various energy efficiency measures such as introducing a capacitor

bank for Power Factor Correction and utilizing daylight in the trough area, utilizing gravity flow

for water supply,etc. However, energy efficiency could be further improved by implementing the

recommendations made in this report.

Adscriptionabout the present situation of energy usage and the observations made by the audit

team along with the recommendation for energy reduction and current baseline for energy

consumption are also indicated in this report.

DuliellaTeaFactory is a medium scale,low grown factory with orthodox tea manufacturing

process producing 2,000 -2,500kg of made tea per day. The factory is equipped with 14 troughs

for withering process, 7 rollers, 2 dryers and 3colour sorters for the production.

The Factorymeetsitselectricityneedsfrom the national grid via a 100 kVA transformer while

thermal energy needs from firewood bought rom outside suppliers. Diesel is used for

standbygeneratorof185 kVA capacity. Monthly average electricity bill of thefactoryamounts to

LKR400,000.00 and average monthly cost of firewood for the hot air generatorsamountstoLKR.

356,000.00.

Ithasfound that DuliellaTea Factory has a great potential forimproving the efficiency of energy

utilization. The estimated saving by implementing the energy efficiency improving measures

identified by the energy auditshall bearound30% which is approximately equivalent to a

financial saving of LKR 2.3 million per annum.The investments required towards these

improvements would be approximately xxx with a pay back period of xxx.

This could be further improved by high investments projects such as introducing bio mass

steam boiler system, Net Metering solar power system, etc.In such a case the investments

required would be around xxx, the savings would be around xxx per annum with a pay

back period of xxx.

ISB recommends that the low cost measures listed in this report with obvious savings be

immediately implemented.

Summary of recommended energy conservation measures, annual energy savings and cost savings are

given in the table below;

Comment [S3]: All costs in US $ also forinternational audience

Comment [l4]: Done


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka VI


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Recommended

Energy Efficiency

Measure

Anticipated

Energy

Saving

Anticipated Annual

Financial Saving

(LKR)

Estimated Cost of

Implementation

(LKR)

Simple

Payback Period

in Years

Section

ELECTRICAL

R1.

Operate troughs at their maximum carryingcapacities as per TRI norm which is 900 kg.Therefore, one trough can be taken off fromoperation under normal circumstances.

21,240 kWh 276,120.00 Nil Immediate

WITHERINGSECTION

R2. Introduce VSD controllers to troughs. Thefactory could give the priority to trough no 1, 5,6 9, 10 & 12 which are operated for longerduration after reaching the withering conditionand rest after words.

24,108 kWh 313,000.00 1.2 M 2.5

R3. Load the troughs depending on their electricalefficiency as the hot air temperature is reachingmost of the troughs without any interruption.

Loading frequency should be 14, 11, 6, 1, 12, 2, 3, 10, 13, 9, 4.

R4. Introduce 2 kW high efficient (80% or higher)motors (HEMs) for the process for futurereplacements with light weight fans and a properoverloading breaker system.

31,400 kWh 440,000.00 2.1 M 5

R5. Replace the oversize motors with 5 kW highefficient motors (HEMs) which are with morethan 85% efficiency in future replacements alongwith a proper overload breaker system.

22,600 kWh 317,000.00 1.6 M 5.1

ROLLING

SECTION

R6. Introduce soft starters for the rollers to minimizethe sudden peaks during batch operation.

240 kVA 138,000.00 175,000.00 1.3

Comment [S5]: One coulumn for USD too

Comment [l6]: Included in USD


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Comprehensive Energy Audit - Draft Report Duli ella Tea Factory

Indu strial Services Bureau (I SB) - Kurunegala, Sri Lanka VIII

R7. Introduce steam radiator system for the eachtrough and avoid utilizing the main fan forwithering process.

22,764 kWh 318,600.00 1 M 3.1

DRYER

SECTION

R8. Introduce7.5 kW high efficient (80% or higher)motors (HEMs) for the process for future

replacements

4,552 kWh 63,700.00 250,000 3.9

R9. The norm is to run the compressors at the lowestpressure to match the system need. Anyadditional increase in 1 bar will increase energyconsumption around 8%. So operate thecompressors at 4-7 bar range.

5,672 kWh 79,410.00 Nil immediate

SIFTINGSECTION

R10.Connect the two tanks of Meiji compressors tothe Hansi compressor and operate the all coloursorter with it while keeping the Meijicompressors standby.

5,190 kWh 72,600.00 Nil immediate

R11.OR

Introduce a screw compressor with 1500 liters/minute coupled with an air dryer and an airreceiver and operate at 4-6 bar range.

7,600 kWh 106,400.00 700,000.00 6

R12.Increasing the awareness of the employees onthe maximum demand variation.

This will contribute to reduce the sudden peaks in the maximum demand

MAINPANEL

R13.Introduce separate breakers for key sectionsalong with electricity meters and connect to thesub breakers and record the sectional powerconsumption daily.

This is contributing to work towardsenergy saving in future

LKR 350,000


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Comprehensive Energy Audit - Draft Report Duli ella Tea Factory

Indu strial Services Bureau (I SB) - Kurunegala, Sri Lanka IX

R14.Introduce a automatic synchronous change overfor the generator

240 kVA 264,000.00 400,000.00 1.5

MAIN

PANEL

R15.Introduce a 50 kW net metered solar powersystem for the premises.

72,000 kWh 100,800.00 10 M 9

SUB-TOTAL 2.40 M

THERMAL

R16.

R17.

R18.

R19.

Implement a firewood shed for the day stockRepair the roof

Introduce a FIFO system and educate the feedingteam to maintain

Store the split firewood under the shed for atleast 3 weeks before feeding to the dryer

Introduce a moisture meter to the firewood yardand feed firewood with at least 25% moisture.

74,589 kg 298,359.00 100,000.00 5 months

DRYERSECTION

R20.Introduce a multi fuel bio mass boiler and alongwith a steam radiator system where rice husk,saw dust, firewood and etc which could beutilizedfor thermal energy generation.

570,000 kg 1.5 M 6 M 4

SUB-TOTAL 1.53 M

GRAND TOTAL 3.93 M

Comment [S7]: Seems incomplete

Comment [l8]: Accepted and Completed

Comment [S9]: At least?

Comment [l10]: Less than 25%


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Comprehensive Energy Audit - Draf t Report Dul iella Tea Factory

I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka X

The tables below compare thepresent situation and the specific energy consumption figures with industrial

benchmarks;

Parameter Present Consumption /Situation

Potential Savings Percentage

Savings

Electrical Energy

kWh

kVA

402,000

1,061

137,000

480

32%

45%

Thermal Energy

Firewood (without

Biomass Boiler)

Firewood (with

Biomass Boiler)

1.15 M

1.15 M

74,000 kg

640,000 kg

6.4%

55%

Parameter Factory Baseline SLSEA Baseline SWITCH-Asia

Baseline for Low

Grown

Specific Electrical Energy

Consumption (SEEC)

0.71

kWh/ kg of MT

0.63

kWh/ kg of MT

0.69

kWh/ kg of MT

Specific Thermal Energy

Consumption (STEC)

7.04

kWh/ kg of MT

- 8.05

kWh/ kg of MT


Consumption (STEC)

25.33

kJ/ kg of MT

Specific Firewood

Consumption (SFWC)

2.036

kg / kg of MT

1.78

kg/ kg of MT

2.44

kg / kg of MT

Specific CO2Emission

(SCO2E)

0.0069

Ton/ kg of MT


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka XI

Content

ABBREVIATIONS ........................................................................................................................ II

ACKNOWLEDGEMENT ............................................................................................................. III

EXECUTIVE SUMMERY ............................................................................................................IV

CHAPTER 1: INTRODUCTION AND BACKGROUND .................................................... 1

1.1 Background ....................................................................................................................... 1

1.2 Objective ........................................................................................................................... 1

1.3

Methodology Adopted for the Comprehensive Energy Audit .......................................... 1

1.4

General Details of the Factory .......................................................................................... 2

1.5 Energy Supply and Utilization ........................................................................................43

1.6 Instruments Used .............................................................................................................87

1.6.1 Energy Audit Team .....................................................................................................98

CHAPTER 2: BREIF DESCRIPTION OF MAJOR ENERGY CONSUMING AREAS

109

2.1

Electrical Energy System ..............................................................................................109

2.1.1

Demand profile and power quality ............................................................................ 119

2.1.2 Line Current Variation .............................................................................................1310

2.1.3

Line Voltage Variation ............................................................................................1411

2.2 Thermal Energy System ..............................................................................................1412

2.3 Main Energy Utilities ..................................................................................................1512

2.3.1 Withering Section ....................................................................................................1613

2.3.2

Rolling Section ........................................................................................................1714

2.3.3

Drying section..........................................................................................................1815

2.3.4 Sifting Section .........................................................................................................1816

2.3.5 Generator .................................................................................................................1917

CHAPTER 3: ANALYSIS OF MAJOR ENERGY CONSUMING AREAS .................2018


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka XII

3.1

Electrical...................................................................................................................... 2018

3.1.1 Withering Section ....................................................................................................2018

3.1.2 Rolling Section ........................................................................................................2220

3.1.3 Dryer Section ...........................................................................................................2321

3.1.4 Sifting Section .........................................................................................................2422

3.1.5 Main Panel ...............................................................................................................2624

3.2

Thermal .......................................................................................................................2927

3.2.1

Withering Section ....................................................................................................2927

3.2.2 Drying Section .........................................................................................................3028

3.2.3 Generator .................................................................................................................3432

CHAPTER 4: CONCLUSIONS AND RECOMMENDATIONS ...................................3735

4.1 Recommendations .......................................................................................................3735

4.2 Conclusions .................................................................................................................4038


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka XIII

List of Tables

Table 1: Baseline Comparison ......................................................................................................... 4

Table 2: List of Measuring Instruments Used during the Comprehensive Audit .......................... 87

Table 3: Details of the Withering Section..................................................................................1614

Table 4: Details of the Rolling Section ...................................................................................... 1715

Table 5: Details of the Air Heaters ............................................................................................1815

Table 6: Details of the Dryers ....................................................................................................1816

Table 7: Details of the Colour Sorters .......................................................................................1916

Table 8: Power Consumption Analysis for the Withering Section ............................................2018

Table 9: Observation & Recommendation for Withering Section ............................................. 2119

Table 10: Power Consumption Analysis for Rolling Section .................................................... 2220

Table 11: Observation & Recommendation for Rolling Section ............................................... 2321

Table 12: Power Consumption Analysis for Dryer Section....................................................... 2321

Table 13: Observation & Recommendation for Dryer Section ................................................. 2422

Table 14: Power Consumption Analysis for Sifting Room ....................................................... 2422

Table 15: Operational Condition Analysis of Colour Sorters ....................................................2523

Table 16: Observation & Recommendation for Sifting Section ................................................ 2624

Table 17: Observation & Recommendation for Main Panel ..................................................... 2826

Table 18: CFM Details of the Withering Troughs .....................................................................2927

Table 19: Flue Gas Analysis for the Air Heater ........................................................................ 3028

Table 20: Energy Dissipation of the Hot Air Generator ............................................................3129

Table 21: Energy Dissipation of Dryer 1 ...................................................................................3331

Table 22: Saving Percentages According to the Moisture Content of Firewood ......................3331

Table 23: Observation & Recommendation for Drying Section ............................................... 3331

Table 24: Results of the Flue Gas Analysis of Generator .......................................................... 3634

Table 25: Observation & Recommendation for Generator ........................................................3634


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I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka XIV

List of Graphs & Figures

Graph 1: Monthly Variation of the Baseline of Firewood and Electrical Energy Consumption ...65

Graph 2: Energy Share of Duliella Tea Factory ............................................................................ 76

Graph 3: Energy Cost Share of Duliella Tea Factory .................................................................... 76

Graph 4: Monthly Variation of Energy Resources Vs Production (Made Tea) ............................87

Graph 5: Maximum Demand Variation ....................................................................................... 119

Graph 6: Variation of the Power Factor .....................................................................................1210

Graph 7: Line Current Variation of the Main Panel .................................................................. 1311

Graph 8: Line Voltage Variation ...............................................................................................1411

Graph 9: Firewood Consumption Variation for an Operation Day ...........................................1412

Graph 10: Electrical Energy Balance for a Day Operation ........................................................1513

Graph 11: Firewood Utilization for a Day Operation ................................................................1613

Graph 12: Load Variation during a Day Operation ...................................................................2725

Graph 13: Voltage Variation of the National Grid Due to Poor Power Quality ........................2725

Graph 14: Firewood Consumption Variation for a Day ............................................................3028

Figure 1: Shanky diagram of the Air Heater 1 ........................................................................... 3129

Figure 2: Shanky diagram of the Dryer 1 ..................................................................................3230

Graph 15: Line Current Variation of the Generator ...................................................................3533

Graph 16: Line Voltage Variation of the Generator .................................................................. 3533
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Comprehensive Energy Audit- Draf t Report Dul iella Tea Factory

I ndustri al Services Bur eau (I SB) - Kur unegala, Sri Lanka 1

CHAPTER 1:

INTRODUCTION AND BACKGROUND

1.1 Background

The tea sectorrice industryin Sri Lanka has always been a vital component of its economy. Rice

is the staple food of the inhabitants of Sri Lanka. Paddy crops are cultivated as a wetland

crop in all the districts. The total land devoted for paddy is estimated to be about 708,000

Hectares at present. There are two cultivation seasons namely; Maha and Yala which are

synonymous with two monsoons. Maha Season falls during North-east monsoon from

September to March in the following year. Yala season is effective during the period from

May to end of August. When the crop is sown and harvested during above periods, the

particular season is defined. However, the whole area devoted for paddy is not being

cultivated due to number of reasons such as shortage of water during the seasons,

prevailing unsettle conditions on the ground, etc.

Sri LankaAnuradhapura District is the world's thirdfourthlargest producer of black teariceand

the industry is one of the country's districts main sources of foreign exchangeincome and a

significant source of income for employees, with tea accounting for 2% of the GDP of the

country with 2 million employed directly and indirectly comprising 10% of the Sri Lankan

population. There are about 700 tea factories in operation in the country.The tea industry is one

of the energy intensive food processing sectors consuming both electrical and thermal energy.

The sources of thermal energy are xxxxAccording to the statistics of Sri Lanka Sustainable

Energy Authority (SLSEA), the tea industry ranks 8 in terms of electrical energy use and is

responsible for 5.23% of the electricity consumption of the entire industrial sector in Sri Lanka.

Electricity is used to run machinery and thermal energy is used to reduce the moisture content of

green leaves from 70%80% down to 3%.

1.2

Objective

The main objectives of the comprehensive Energy Audit are is to determine thecurrent baselines

namely amount of electrical and thermal energy utilized, where they are being used and to find

out the most viable and practical ways of reducing the energy consumption and associated cost.

Any reduction in the energy consumption would also translate into lesser green house gas

emissions, reducing the carbon footprint of the factory operations. The report provides

suggestions to improve the energy efficiency and to overcome shortcomings associated with

energy utilities. Furthermore, this report intends to improve the awareness of managers &

technical staff of Duliella Tea FactoryPradeep Rice Mill on the importance of Energy

Management for the enhancement of the productivity.

1.3

Methodology Adopted for the Comprehensive Energy Audit

Step 1 - Document Review for Past Energy Data

During the walkthrough audit and subsequent kick off meeting with the factory personnel, the audit

team obtained an idea on the average energy consumption and costs involved. Records were reviewed

Formatted:Font color: Red

Comment [S11]: Is it only 2 %??

Comment [l12]: Extract from the TOR

Formatted:Font: 12 pt, Font color: Red

Comment [NPEJ13]: complete


Comment [l14]: Included

Formatted:Font: 12 pt, Font color: Red



16/56



to collect past data related to energy consumption as well as cost information for a period of past 12

months. The factory baseline energy consumption was established from past data to compare with the

country baselines.

Step 2 -Facility Inspection, Energy Monitoring and Evaluation

The major energy consuming units and processes were further investigated and field measurements

were taken to obtain operating parameters.

Step 3 - Identify/Evaluate Feasible Energy Conservation Mechanisms

A list of major energy conservation mechanisms along with key observations were developed for all

major energy consuming systems (i.e., withering, rolling, drying, lighting, siftingsoaking, drying,

milling, polishing, etc). Based upon a final review of all information and data gathered, and also

based on the operational requirements obtained from the factory personnel, a finalized list of energy

conservation measures was developed.

Step 4 Preparation of the Energy Report

The findings and recommendations are summarized in this energy audit report. The report includes a

description of the factory, itsitsoperation, a discussion of all major energy consuming systems, a

description of all recommended energy conservation mechanisms with their specific energy impact,

implementation costs, benefits and payback periods.

Step 5Presenting the Audit Findings to Factory Personnel

The findings of the energy audit will be presented to factory personnel (especially to the energy

conservation team). All observations, current issues, recommendations and cost saving opportunities

together with contact details of prospective equipment and technology suppliers will be presented.

Step 6-Submition of Final Report

After receiving the comments/ feedbacks fromreviewing the draft report by ISBIFCconsultants, the

draft report will be revised and the final report will be submittedto IPHT.

1.4 General Details of the Factory

Company Name

Group

Address

District

Province

Duliella Tea FactoryPradeep Agro Mart RiceMills Holdings (Pvt) Ltd

Andaradeniya Estate Pvt Ltd

Kosmilla, NeluwaSaliya Mawatha,Anuradhapura.

GalleAnuradhapura


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Southern ProvinceNorth Central Province

Contact Person

Designation

Contacts

Mr. M.D. Premachandra

Manager

Tel : 09125-5635003226065 Fax Mob1 :09171-56350039684227

Mob2: 077-22936977915955

Year of establishment 19802013

Factory Classification Elevation Technology : Low Grown SemiAutomated

Type of tea rice manufacture :OrthodoxparboiledRice

Factory Capacity 20,0002,500 kg Made TeaRiceper day

Key Machineries Available Troughs Dryer - 141nos.

Rollers Boiler - 17nos.

Dryers Polisher - 2 1 nos.

Colour SortersDe Stoner - 3 1 nos.

Husker - 2 nos

Paddy Cleaner - 1 nos

Whitener - 3 nos

Bran Separator - 2 nos

Colour Sorter - 1 nos

Silky Polisher - 1 nos

Grader - 2 nos

Separator - 1 nos

Approximate Distance from

ColomboEmployee Details220 kmDirectors -04

Managers- 06

Formatted:Font: 12 pt, Highlight

Formatted:Line spacing: single




Formatted Table


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Skill Workers- 50

Approximate Distance from Colombo 150 km

1.5 Energy Supply and Utilization

The energy recourses utilized in DuliellaTea FactoryPradeep rice millare Electricityand Paddy

Husk, Firewood and Diesel. Firewood Paddy Husk is for drying and withering parboiling

processes and Diesel electricity is utilized for the standby generatormachinery.

Electricity to the factory is from the national grid via a dedicated transformer with 100 kVA

capacity under the Industrial Tariff 2 (I-2). A 185kVAcapacity standby generatorisinstalled for

emergency power requirement. There are 14 3 troughswhiteners, 7 1 rollers Huskerand3 , 1

compressors Polisher and a for colour sorters with compressor consuming the major part of

electricity.

Average maximum demand and the electricity consumption for the past 12months were88 kVA

and 33,513 kWhrespectively corresponding to the average monthly production of 46,960 kg of

Made Teaparboiled rice.The average firewood paddy husk consumption is 95,600 kilograms.

Thermal energy, which is generated from the burning of firewoodpaddy husk, is utilized for two

dryers of 270 kg/hr and 140 kg/hr capacitiesy. The hot airsteam generated is also utilized for

withering parboilig processes. 140 kg/hr air heater is kept as a standby unit for the drying

process. The hot air generatordryeroperates almost20 hours per day batch forboth drying and

withering processes. Hot airSteam is supplied for withering parboiling process in order tomaintain the desired temperature differencebetween the dry and wet bulb temperatures and to

improve the withering process.

Mix firewoodPaddy Huskis used with the average moisture content of above 3510% for feeding

into the hot air generatorsteam boiler. The average monthly Paddy Huskfirewoodconsumption

for drying and withering parboilingprocess is around 105,000 kg. The Average purchasing price

of firewood is LKR. 950.00 per yard, whichisapproximately 293 kg.Paddy husk is available free

as a byproduct of the rice processing.

Table 1: Baseline Comparison







Comment [S15]: Per annum? Per month? Seethe number mentioned in the below paragraph ishigher.

Comment [l16]: Per month



Comment [S17]: What is mix fire wood?

Comment [l18]: Changed to firewood. This islocal term for firewood with rubber firewood and

jungle firewood composition. The term was remofrom the report.



19/56



Parameter Factory Baseline SLSEA Baseline SWITCH-Asia

Baseline for Low

Grown

Specific Electrical Energy

Consumption (SEEC)

0.71

kWh/ kg of MT

0.63

kWh/ kg of MT

0.69

kWh/ kg of MT


Consumption (STEC)

7.04

kWh/ kg of MT

- 8.05

kWh/ kg of MT


Consumption (STEC)

25.33

kJ/ kg of MT

CHAPTER 2: CHAPTER 3:

Specific FirewoodConsumption (SFWC)

2.036

kg / kg of MT

1.78

kg/ kg of MT

2.44

kg / kg of MT

Specific CO2Emission

(SCO2E)

0.0069

Ton/kg of MT

CHAPTER 4: CHAPTER 5:

Note: In two different contexts and occasions, Sri Lanka Sustainable Energy Authority (SLSEA) and SWITCH-

Asia Project established industry wide specific energy consumptions for the tea industry and the figures indicated

above are the industry average values based on two different samples of tea factories.

Table 1 compares the specific energy consumption of Duliella tea factoryPradeep Rice Millwith

that of two national level baselines. Though the specific electricity consumption of the Duliella

tea factory is slightly over the industry average as per the two sources indicated,still there is room

for further improvements, which will be described under the observation and recommendation

section. In case of thermal energy (firewood), there appears to be a higher potential for saving.

The specific energy consumption for a tea manufacturing facilityrice milling facility is an

indicator giving of the energy consumption per for a unit of production which in this case is 1 kg

of Made Teaparboiled rice. The fluctuation of energy consumption with respect to productionis

clearly highlighted in specific energy consumption figures.





Formatted:Font: 12 pt, Font color: AccentHighlight


Formatted:Highlight


Formatted:Highlight


Formatted:Highlight


Formatted:Highlight


Formatted:Highlight


Formatted:Highlight


Formatted:Highlight


Formatted:Highlight

Formatted:Font: 12 pt, Not Bold, Highlight

Comment [S19]: Ok good.

You should recommend which baseline is relevanmore for this factory and what their targets shoul

be. This must be part of the exercise.

Comment [l20]: Better to take SWITCH baseas it focused to low grown tea manufacturing


Formatted:Highlight

Formatted:Font: 12 pt




Comment [S21]: ?

Comment [l22]: removed



20/56



The specific electrical energy consumption varies between 0.6 and 0.8 kWh per 1 kg of made tea

during the year 2012/2013. The highest figure wasin September and August 2012, and that

was0.80kWh per 1 kg of made tea. Therefore, the baseline for specific electrical energy

consumption for Duliella Tea Factory is 0.71 kWh per 1 kg of made tea.

The specific firewood consumption of Duliella tea factor varies between 1.2 and 2.84 kg per 1 kg

of made tea during the year 2012/2013. The highest value was in December 2012 and from

December 2012 to April 2013 specific firewood consumption was more than 2.3 kg per 1 kg of

made tea. This is mainly due to the increase of rainfall in those months, which contributes to

increased moisture in firewood xxxx . Since paddy husk is freely available in the factory, theconsumption was not recorded in the past. But the average specific paddy husk consumption per

1000kg of parboiled rice is xxxxx as per the analysis conducted by the ISB consultants.

The relationship between production and the electrical energy consumption is given by the

equation; Y = 0.303X + 19,283wherein; Y=electrical energy consumption in kWh & X=Made

Tea productionParboiled Ricein kg.

The relationship between production and the specific firewood consumption is given by the

equation; Y = 3.121X 50,967wherein; Y= firewood consumption in kg& X=Made Tea

production in kg.

-

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

-

0.50

1.00

1.50

2.00

2.50

3.00

Month

SEEC(kWh/kgofMT

)

SFWC(kg/kgofMT)

Specific firewood consumption variation Specific electrical Energy Variation

Graph 1: Monthly Variation of Specific Firewood and Electrical Energy Consumption






21/56



Graph 2 explains the Energy Share of Duliella Tea Factory. Thermal energy is utilized in a

dominant way and it is 89%. This is a common situationin most of the Sri Lankan tea

factories.The thermal energy load for thefactoryis shared by firewood and diesel for the stand-by

generator. The Graph 3represents the resourcewise energy cost share for the factory and the

electricity is the major cost element (53%), followed by firewood which is 30%. Diesel shares

17% of the energy cost. This relatively high shareis mainly due to the frequent power

interruptions in the national electricity supply in the area where the factory is located.

Electrical Energy11%

Thermal Energy89%

Electricity53%

Firewood30%

Diesel17%

Graph 22: Energy Share of Duliella Tea Factory

Graph 33: Energy Cost Share of Duliella Tea Factory


Formatted:Font: Bold, Highlight

Formatted:Highlight


Formatted:Highlight


22/56



According to Graph 4, the electrical energy utilization pattern is closely co related to the

production up to May 2012 from April 2013. The firewood consumption during the high rainy

season from December 2012 to January 2013 is very high which could be attributed to wet

firewoodbut it has a linear relationship during the rest of the period.

5.1

Instruments Used

Table 2: List of Measuring Instruments Used during the Comprehensive Audit

Instrument Measuring Parameters

Flue Gas Analyzer

Type : Kane May

Make: UK

O2, CO, Combustion efficiency, CO2, NOx, SO2,NO, Excessair, ambient temperature, Flue gas temperature

Data Loggers

Type : DENT Pro

Make: USA

Current, kW, Power factor, Voltage, kVAr, kVA, harmonics(maximum, minimum, average, instantaneous, or all parameterslogging)

Thermometer K Temperature (C /F)

-

10,000

20,000

30,000

40,000

50,000

60,000

-

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

Month

Elect

ricalEnergy(kWh)|MadeTea(kg)

Firewood(kg)

Firewood Consumption (kg) Electrical Energy Consumption (kWh) Made Tea (kg)

Graph 4: Monthly Variation of Energy Resources Vs Production (Made Tea)


Comment [S23]: This can come as an annexNot here

Comment [l24]: Included in the annex


Formatted:Highlight


23/56



Model: S 506

Make : India

Thermometer IR

Type: Hioke

Make:Japan

Temperature (C /F)

Rh logger

Type :Testo

Make: Germany

Relative humidity, Temperature (C/F) (maximum, minimum,instantaneous, logging)

Power meter

Type : HIOKI

Make: Japan

Current, kW, Power factor, Voltage, kVAr, kVA, frequency

(instantaneous)

Portable data logger(Energy monitoring socket)Make: UK

Single phase Current, Voltage, kW and kWh

Wind meter

Make: India

Wind velocity, flow rate

Velo meter

Make: Germany

Air Flow

Lux Meter Lux level/ illumination level

5.1.1

Energy Audit Team

5.1.1

1. Eng. GaminiSenanayake Team Leader

2.1.Eng. LoshanPalayangoda - ISB Contact PointSenior Consultant

3.2.Eng. ChanakaMahawatta - Consultant

4. Eng. ChamilaWickramasingheThilanka Alwis - Tranee Consultant

3.

4. Sachindra Weerasooriya - UG Trainee

5. Mohommed Ziham - UG Trainee

5.6.NalakaWeerasekara Technical Officer

Formatted:Normal,Normal LIP, No bulletsnumbering

Comment [S25]: Can come in annex

Comment [l26]: Included in the Annex


24/56



7. JagathBandara - Technical Officer

6.

CHAPTER 6:

BREIF DESCRIPTION OF MAJOR ENERGY

CONSUMING AREAS

6.1

Electrical Energy System

The CEB meters electricity consumption at the main panel. However, there is no facility to meter

the power consumption of individual processes or equipment (sub metering facility). . Also, the

self generated electricity using Diesel Generator setsis not metered.Ascribed to these situations,

it is thus difficult to evaluate the energy consumption pattern with respect to the production

output in each process. Monitoring and reviewing of energy consumption in each process is one

of the key elements in efficient energy management system and it is strongly recommended to

install individual energy meters for major energy consuming areas such as witheringPolishing,

rollingWhitening, sifting, drying and colourcolorsorters.

The main panel along with key electrical energy consuming components was measured with the

power loggers. Electrical power demands of the main panelwerewas logged separately along

with other important parameters like kW, kVA, PF, I, V, etc. via electrical power loggers for a

period of 24 hrs at Duliella Tea FactoryPradeeep Rice Mill. Measurements were taken from

0611th- JuneFebruary-20134, 1613:1500 pm to 0712-JuneFebruary-20134, 162:15.

pm.SSpecially, the troughs, rollers, compressors and dryersall machinerywere closely monitored

for individual power consumptionusing portable data analyzing instrument.

Formatted:Indent: Left: 0.5", No bullets

numbering

Comment [S27]: This is not good. The auditteam should look at the diesel consumption as weas the efficiencyKwh per litre of Diesel.

Comment [l28]: This is by the factory NOTthe Audit team

Formatted:Font: 12 pt, Superscript


25/56



6.1.1

Demand profile and power quality

Graph 6 describes the behavior of the maximum demand of the main panel. Factorys peakdemand occur around 09.00 hrswhen operation of all major production units (withering, rolling

and dryingPolishers, Huskers, Whitener) takes place simultaneously and contribution from the

outside line. The maximum demand of 12275kVA was registeredon the day where the recording

was done.

Graph 64: Maximum Demand Variation11/02/2014 13.0012/02/2014 12.15

Graph 6: Maximum Demand Variation 12/02/2014 16.0013/02/2014 15.15

0

20

40

60

80

100

120

140

16:15

17:00

17:45

18:30

19:15

20:00

20:45

21:30

22:15

23:00

23:45

0:30

1:15

2:00

2:45

3:30

4:15

5:00

5:45

6:30

7:15

8:00

8:45

9:30

10:15

11:00

11:45

12:30

13:15

14:00

14:45

15:30

16:15

kW/kV

A

Time

kW kVA

0

5

10

15

20

25

30

13:00:00

13:45:00

14:30:00

15:15:00

16:00:00

16:45:00

17:30:00

18:15:00

19:00:00

19:45:00

20:30:00

21:15:00

22:00:00

22:45:00

23:30:00

0:15:00

1:00:00

1:45:00

2:30:00

3:15:00

4:00:00

4:45:00

5:30:00

6:15:00

7:00:00

7:45:00

8:30:00

9:15:00

10:00:00

10:45:00

11:30:00

12:15:00

kW/kVA

kW kVA



Formatted:Normal,Normal LIP


26/56



The peak points occurred from 7:30 hr to 14:00 hr is due to the rolling process as it is done inbatch wise in 20 minutes intervals. The peak occurred around 01:00 hrdue to the loading of all

the troughs along with the compressors of the colour sorters.

020406080

100120140160180200

16:00:00

16:45:00

17:30:00

18:15:00

19:00:00

19:45:00

20:30:00

21:15:00

22:00:00

22:45:00

23:30:00

0:15:00

1:00:00

1:45:00

2:30:00

3:15:00

4:00:00

4:45:00

5:30:00

6:15:00

7:00:00

7:45:00

8:30:00

9:15:00

10:00:00

10:45:00

11:30:00

12:15:00

13:00:00

13:45:00

14:30:00

15:15:00

kW/kVA

kW kVA

0

0.2

0.4

0.6

0.8

1

1.2

16:15

17:00

17:45

18:30

19:15

20:00

20:45

21:30

22:15

23:00

23:45

0:30

1:15

2:00

2:45

3:30

4:15

5:00

5:45

6:30

7:15

8:00

8:45

9:30

10:15

11:00

11:45

12:30

13:15

14:00

14:45

15:30

16:15

PF

Time PF

Graph 45: Variation of the Power Factor

Formatted:Font: Not Bold


27/56



Graph 7 depicts the power factor variation of the main panel for the measured 24 hour duration.

The power factor varied from 0.67 to 0.99.The average power factor was 0.96whichis

anacceptablelevel. The minimum power factor was 0.67 and it occurred at 12:30 hrs. As this did

not occur during the factory peak time, it has no impact on the maximum demand.

6.1.2 Line Current Variation

The line current variation is useful to find out the imbalances in threephases.According to the

Graph 8,there is no significant imbalance of line currents. The imbalance doe not exceeds 5%

which is the desired limit.

0

20

40

60

80

100

120

140

16:1

5

17:0

0

17:4

5

18:3

0

19:1

5

20:0

0

20:4

5

21:3

0

22:1

5

23:0

0

23:4

5

0:3

0

1:1

5

2:0

0

2:4

5

3:3

0

4:1

5

5:0

0

5:4

5

6:3

0

7:1

5

8:0

0

8:4

5

9:3

0

10:1

5

11:0

0

11:4

5

12:3

0

13:1

5

14:0

0

14:4

5

15:3

0

16:1

5

A

Time CH 01 (A) CH 02 (A) CH 03 (A)

Graph 56: Line Current Variation of the Main Panel


28/56



6.1.3

Line Voltage Variation

The line voltage variation is an indicator to identify the power quality supplied by the nationalgrid. Graph 9 explains the behavior of the voltage of the main panel respectively. The variation in

the line voltage is exceeding the accepted limit of 5%.

6.2 Thermal Energy System

Firewood is used to generate thermal energy required for the dryer operation. The factory does not have amechanism to record the firewood consumption.Therefore, the audit team had to make hourly measurements duringthe testing period. The firewood was measured in yards and at an accuracy of 0.5, thus the reading could contain anerror of +/- 0.5 yards. Introducing of a

weighing scale to the Heater room will be an added advantage to the factory to have a true

picture of daily firewood consumption. The total firewood consumption for the 24 hours from

06-June-2013 16:30 hrs to 07-June-2013 16:30 hrswas 4,149.5 kg which is slightly higher than

the daily average taken from the monthly records of 3,825 kg. This could be attributed to high

consumption in rainy days.

0

50

100

150

200

250

300

350

400

450

kW/kVA

Time Firewood (kg)

205

210

215

220

225

230

235

240

245

16:15

17:00

17:45

18:30

19:15

20:00

20:45

21:30

22:15

23:00

23:45

0:30

1:15

2:00

2:45

3:30

4:15

5:00

5:45

6:30

7:15

8:00

8:45

9:30

10:15

11:00

11:45

12:30

13:15

14:00

14:45

15:30

16:15

V

Time CH 01 (V) CH 02 (V) CH 03 (V)

Graph 67: Line Voltage Variation

Comment [S29]: Then this should be suggestas a recommendation. Some one should know atleast on a monthly basis how much they areconsuming

Comment [l30]: Included under theRecommendations

Comment [S31]: Suggest this as arecommendat ion. Not here .

Comment [l32]: Included under theRecommendations


29/56



6.3

Main Energy Users

The energy utilization of main sections likes of withering, rolling, sifting, drying and colour

sorters at Duliella tea factory is described below;

Graph 10 depicts the electrical energy balance of Duliella tea factory for a day operation

considering all the sections contributing for electricity consumption. The main electrical energy

consuming area is the withering process with 36% share, followed by Colour sorters andsifting

with18% each. Dryer & heatershare is 14% and the share of rollers is 13% for the rollers. The

impact of the illumination system is very low for Duliella tea factory.

Graph 11 expresses the firewood utilization for the withering and the drying processes and as

expected the drying process consumes more than 70%.

Whithering36%

Dryer & Heater14%

Compressors &Colour Sorters

18%

Lighting1%

Sifting18%

Rolling13%

Graph 89: Electrical Energy Balance for a Day Operation


30/56



6.3.1

Withering Section

Withering is used to remove free as well as embeddedwater of green tea leaves and allows a very

slight amount of oxidation. This is the major electricity consuming section, whichis in operation

for more than 14 hours every day.

Table 3: Details of the Withering Troughs

Machine Size

(feet)

Rated

Power

(hp)

Rated Power

of

blower(kW)

Speed

(RPM)

No of

Blades

in the

Blower

Capacity

(kg)

Trough No 1 60' x 6' 5.50 4.10 960 7 795

Trough No 2 60' x 6' 5.50 4.10 960 7 795

Trough No 3 60' x 6' 5.50 4.10 960 7 795

Trough No 4 60' x 6' 5.50 4.10 960 8 795

Trough No 5 60' x 6' 3.50 2.61 960 6 795

Trough No 6 60' x 6' 5.50 4.10 960 6 795

Trough No 7 60' x 6' 5.50 4.10 960 5 795

Trough No 8 60' x 6' 3.50 2.61 960 6 795

Trough No 9 60' x 6' 5.50 4.10 960 6 795

Trough No 10 60' x 6' 3.50 2.61 960 6 795

Whithering

27%

Drying73%

Graph 910: Firewood Utilization for a Day Operation


31/56



Trough No 11 60' x 6' 7.50 5.60 960 6 795

Trough No 12 60' x 6' 5.50 4.10 960 6 900

Trough No 13 60' x 6' 5.50 4.10 960 6 900

Trough No 14 60' x 6' 5.50 4.10 960 6 950Total Rated

Power73.00 54.46

6.3.2 Rolling Section

The rolling section is with 7 rollers and two are with double action and the rest are with fixed bed

single action. As per the literature, the rolling action also causes some of the sap, essential oils,

and juices inside the leaves to ooze out, which further enhance the taste of the tea. The rollingsection operates an average of 7 hours per day from 7:30 am to 2:00 pm.

Table 4: Details of the Rolling Section

Roller No Rolling Step Brand

Size

(inches)

Loading

Capacity (kg)

Motor

Capacity (hp)

01 1st

SIROCCO

Double Action 47 220 15

02 1st

SIROCCO

Double Action 47 220 15

03 4th CCC 47 11% 3rddhools 15

04 2nd CCC 47 15% 1stdhools 15

05 2nd Browns 47 15% 1stdhools 14 (Old Motor)

06 3

rd

CCC 34 20% 2nd

dhools 10

07 3rd CCC 40 20% 2nddhools 14 (Old Motor)


32/56



6.3.3

Drying section

The drying section consists of the air heater which generates hot air from firewood and the dryeruses hot air to dry the fermented tea. The dried or fired tea is usually has less than 3% moisture

level. The dryer is also used for the transferring of hot air for the withering process to expedite

the process. Dyer No 1 is for regular use while Dryer No 2 is either kept as a stand-by or used

during high crop season. Thus the main fan (Induced Draft Fan) of Dryer No 1 is in operation for

nearly 22 hours per day.

Table 5: Details of the Air Heaters

Identificatio

nNo

Make

(Air Heater)

Average fuel

Consumption

(per hour)

Motor Capacity (hp)

01 Browns 1 Yards

Main fan 15hp

Other 3hp

02 Sirocco 1 Yards

Main fan15 hp

Others3 hp

Table 6: Details of the Dryers

Dryer No BrandNo of

Stages Size (ft)& Type Fired TeaOutput (kg)Motor

Capacity (hp)

01 Browns 25

Belt Conveyer270 1.5

02 Sirocco 35

Belt Conveyer140 1.5

6.3.4 SiftingSection

Grading & sorting operations are done in the sifting section in which tea particles of the bulk are

separated into various grades of different sizes and forms conforming to trade requirements. In

other words, it basically converts the bulk into finished products. The process of sorting has two

objectives (i) to enhance the value (ii) to impart quality. The siftingis the only section operating

round the clock.

The sifting consists of two main operations namely the coloursorting and grading. The three

colour sorters are fitted with 35 hpmotors while the shifters are fitted with nearly 25 hp motors.

Comment [S33]: Include in Kgs too

Comment [l34]: Included in kgs


33/56



Table 7: Details of the Colour Sorters

Identification

No

Make TypeOperating

Pressure

Compressor Details

TypeMotor

Capacity (hp)

Set

Pressure

01 Senvac C8000wm 3 bar Reciprocating 10

Pressure

gauge is not

working

02

Super

shizyok

e

NS 40 2.2 bar Reciprocating 10 9-10 bar

03 Nanta7000 D

camera3 bar Reciprocating 15 6-9.5 bar

6.3.5 Generator

Generator is used for emergency power generation. The generator at Duliella tea factory is being

operated at least 100 hrs per month due to the frequent power interruptions in the area. This is

comparatively high due to long lead period of restoring the power by the CEB.

The generator was tested and the load test was carried out to find out the performance. The

specific power generation KWh/ litre of Diesel is found to be xxxx.

Comment [S35]:

Comment [l36]: Compressor is with the colosorter. So taken both together.


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Comprehensive Energy Audit - Draf t Report

Dul iella Tea Factory


CHAPTER 7:

ANALYSIS OF MAJOR ENERGY CONSUMING AREAS

The main sections identified under Chapter 2 are and analyzed under this section to makerecommendations for further improvements. Sections taken in to account are troughs, rollers,

colour sorters (compressors) and dryers, which were closely monitored for individual energy

consumption.

7.1

Electrical

7.1.1 Withering Section

According to the Table 8, some trough motors have a lowerloading factor. Thus, Trough no. 4, 3,

2, 9, 10 & 13consumes high energy compared the trough fans of similar capacity in Duliella tea

factory. This is mainly due to utilization of rewound motors and lack of preventive maintenance

related to motor bearings. Except trough no 12,13 &14, all other troughs are loaded below the

nominal TRI standard quantity of 900 kg for a trough with 60 X 6. The main reason for underloading is theinability of the hot air duct to supply hot air for troughs that are away from the

dryer.In addition, troughs are running at fixed speed right throughout the withering process.

Trough no 1, 5, 6 9,10 & 12were kept running more than four hours even after reaching the

required wither of green leaves.

Table 8: Power Consumption Analysis for the Withering Section

Trough

No

Size

(feet)

Rated

Power (hp)

Rated

Power

(kW)

Actual

Power

(kW)

Loading

Factor

No of

Blades

Capacity

(kg)

Unloading

Time

1

60' x 6'5.50 4.10

3.55 87% 7 795 9.55am2 60' x 6' 5.50 4.10 3.66 89% 7 795 9.10am

3 60' x 6' 5.50 4.10 3.68 90% 7 795 8.35am

4 60' x 6' 5.50 4.10 4.72 115% 8 795 7.30am

5 60' x 6' 3.50 2.61 Under Repair 6 795 13.45pm

6 60' x 6' 5.50 4.10 3.47 85% 6 795 13.10pm

7 60' x 6' 5.50 4.10 2.31 56% 5 795Not

loaded

8 60' x 6' 3.50 2.61 1.75 67% 6 795Not

loaded

9 60' x 6' 5.50 4.10 3.86 94% 6 795 11.05am

10 60' x 6' 3.50 2.61 2.39 92% 6 795 11.50am

11 60' x 6' 7.50 5.60 4.72 84% 6 795 8.15am

12 60' x 6' 5.50 4.10 3.66 89% 6 900 12.35am


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13 60' x 6' 5.50 4.10 3.84 93% 6 900 7.00am

14 60' x 6' 5.50 4.10 3.27 80% 6 950 10.30amTotal

Rated

Power

73.00 54.46

Table 9: Observation & Recommendation for Withering Section

Observation Recommendation with Investment & Payback

OB1. The factory uses different spreadingdensities in troughs, without considering

its carrying capacity.

R1.Operate troughs at their maximum carryingcapacities as per TRI norm which is 900 kg.

Therefore, one trough can be taken off fromoperation under normal circumstances.

Expected Energy saving : 21,240 kWh

Expected Annual Saving: LKR 276,120.00

Estimated Investment : Nil

SPP : Immediate

OB2. Fixed speed motors are employedforwithering troughs. Priority can be givento motors of trough no 1, 5, 6, 9, 10 &12 are running unlit unloading to keepthe leaf condition although it haswithered five hours ago.

R2.Introduce VSD controllers to troughs. Thefactory could give the priority to trough no 1,5, 6 9, 10 & 12 which are operated for longerduration after reaching the witheringcondition and rest after words.



Estimated Investment : LKR 1.2 M

SPP : 2.5 Years

OB3.

Sequence of troughs loadingis based onthe proximity to hot air supply but notbased on their efficiency levels.

R3.Load the troughs depending on theirelectrical efficiency as the hot airtemperature is reaching most of the troughswithout any interruption.Loading frequency should be 14, 11, 6, 1,

12, 2, 3, 10, 13, 9, 4.

OB4. Conventional induction motors areutilized in the section. Conventionalmotors are usually with low efficiency

level (70% or less).

R4.Introduce 2 kW high efficient (80% orhigher) motors (HEMs) for the process for

future replacements with light weight fansand a proper overloading breaker system.

Expected Energy saving :31,400 kWh


Estimated Investment : LKR 2.1 M

SPP : 5 Years

xx

Comment [S37]: A trial of the same should bdone with the plant. IF not working thisrecommendation should be through through.

Comment [l38]: This standard can be achievethe low grown sector.

Comment [S39]: There should be a sectioncalled back up calculations where all calculationsexplained in detail egfor this how you arrive a24108 kwh per annum saving

Comment [l40]: Supporting calculations areprovided in the Annex

Comment [S41]: Its seems to me that some mexplanation of the recommendations needs to bemade, The above way of summarizing therecommendations in table form is good but may bwe can have an explanation section which explaiall the details associated with the observation andrecommendations May be 2 pages.

Comment [l42]: Explained and literature isincluded in the Annex


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7.1.2

Rolling Section

Motors which arerated at20 hp in the rolling sectionare below 6 hp during operation. Therefore,the average loading factor is around 30%. Thus, thesemotors operate at very low efficiency

levels. Therefore, it is better to make a trial with a 10hp motor to check its capability of rollers to

withstand the startup and loading conditionsof rolling. Roller no 07wasdrawing a higher current

as it is a rewound motor which is more than 25 years old.As rolling is a batch operation, motors

have to be switch on and switch off around every 20 minutes. This has resulted in creating peaks

in the power demand pattern of Duliella Tea Factory.

Table 10: Power Consumption Analysis for Rolling Section

Roller

No

Rolling

Step

Size

(inches)

Motor

Capacity(hp)

Motor

Capacity(kW)

Actual

Loading(kW)

Loading

Factor

01 1st 47 15 11.19 2.47 22%

02 1st 47 15 11.19 1.14 10%

03 4th 47 15 11.19 2.14 19%

04 2nd 47 15 11.19 1.86 17%

05

2nd

47

14

(Very Old

Motor)

10.44 1.95 19%

06 3rd 34 10 7.46 2.31 31%

07

3rd

40

14

(Very Old

Motor)

10.44 4.12 39%


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Table 11: Observation & Recommendation for Rolling Section


OB5. Averageloading factor of the motors insection is less than 30%.

R5.Replace the oversize motors with 5 kW highefficient motors (HEMs) which are withmore than 85% efficiency in futurereplacements along with a proper overloadbreaker system.



Estimated Investment :LKR 1.6 M

SPP :5.1 Years

OB6. Rolling is a batch type operation and

rollers are switch-on and switch-off ataround 20 minutes for loading andunloading.

R6.Introduce soft starters for the rollers tominimize the sudden peaks during batchoperation.Expected Energy saving : 240 kVA


Estimated Investment : LKR 175,000.00

SPP :1.3 Years

7.1.3 Dryer Section

Only Dryer No 1 is used while Dryer No 2 is kept stand-by or to utilizedduring the high crop

season. ID fans of both dryersare running below 50% of the rated load.

Table 12: Power Consumption Analysis for Dryer Section

MachineRated Power

(hp)

Rated Power

(kW)

Actual

power (kW)Loading Factor

Dryer 01 2 1.492 0.68 46%

Heater FD Fan 5 3.73 0.47 36%

Heater ID Fan 20 14.92 5.42 44%

Dryer 02 2 1.492Could notmeasure

Heater ID Fan 20 14.92 5.17 36%

Heater FD Fan 5 3.73 0.57 13%

Fiber Met 1 0.746 0.14 35%

Middle ton sifter 1 1 0.746 0.11 15%

Comment [S43]: Give some more detail andexplanation.

Also for each recommendation have a separate baup calculation which covers, in detail how you haarrived at the energy saving figures.

Comment [l44]: Explained and literature isincluded in the Annex.


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Table 13: Observation & Recommendation for Dryer Section


OB7. The dryer main fan is in operation foradditional 14 hours to supply hot air totroughs.

R7.Introduce a steam radiator system (coupledwith the proposed bio mass boiler inrecommendation R22) for each trough andavoid utilizing the main fan for witheringprocess.



Estimated Investment : LKR 1 M

SPP : 3.1 Years

OB8.

Conventional induction motors are

utilized in the section. Conventionalmotors are usually with low efficiencylevel (70% or less).

R8.

Introduce7.5 kW high efficient (80% or

higher) motors (HEMs) for the process forfuture replacements



Estimated Investment : LKR 250,000

SPP : 3.9 Years

7.1.4 Sifting Section

The sifting room is operated for 24 hours and almost right throughoutthe year except for few

days. Therefore, this is one of the key sections responsible for 16% of electricity consumption.

The Compressors of colour sorter are responsible for more than 60% of the total consumption.According to Table 11, except Compressor-Hansin and five-tray shifter, all the motors are

running below 50% of the rated load.

Table 14: Power Consumption Analysis for Sifting Room

Machine Rated Power

(hp)

Rated Power

(kW)

Actual Power

(kW)

Loading

Factor

Middleton Sift 2 1.50 1.12 0.18 12%

Middleton Sift 3 1.00 0.75 0.05 5%

Fiber Met 2 3.00 2.24 0.46 15%

5 trays sifter 2.00 1.49 1.17 59%

Conveyer to 5 trays sifter 1.00 0.75 0.25 25%

Machine Sifter 1 1.00 0.75 0.12 12%

Machine Sifter 2 1.00 0.75 0.26 26%

Machine Sifter 3 1.50 1.12 0.31 20%

Machine Sifter 4 N/A N/A 0.19 N/A


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Machine Sifter 5 1.00 0.75 0.06 6%

Machine Sifter 6 1.50 1.12 0.21 14%

Winnower No 1 Fan N/A N/A 0.02 N/A

Winnower No 1Conveyer

N/A N/A 3.83 N/A

Winnower No 2 Fan N/A N/A 3.00 N/A

Winnower No 2Conveyer

N/A N/A 0.01 N/A

Exhaust Fan N/A N/A 1.42 N/A

Colour Sorter N/A N/A 3.35 N/A

Compressor-Meiji 10.00 7.46 4.88 49%

Compressor-Meiji 10.00 7.46 4.70 46%

Colour Sorter Super

Shizuoka

N/A N/A 0.99 N/A

Compressor-Hansin 15.00 11.19 14.23 95%

Colour Sorter N/A N/A 0.20 N/A

Air Dryer N/A N/A 0.86 N/A

Wood Splitter 3.00 2.24 0.41 14%

Total Power Demand 52.50 39.17 37.84

Table 15: Operational Condition Analysis of Colour Sorters

Identifica

tion

No MakeOperating

Pressure

Compressor Details

Type

Motor

Capacity

(hp)

Set

Pressure

Range

Load & Unload

Duration

01 Senvac 3 barReciprocating

(Meiji)10

Pressure

gauge is

not

working

Load10s (14%)

Unload- 61s (86%)

02

Super

shizyok

e

2.2 barReciprocating

(Meiji)10 9-10 bar

Load15s (22%)

Unload- 54s (78%)

03 Nanta 3 bar

Reciprocating

with auto

cutoff at

unload

(Hansin)

15 6-9.5 bar

Load31s (11%)

Unload- 263s (89%)


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Table 16: Observation & Recommendation for Sifting Section


OB9. The compressors are set at 9-10 baroperating range while the colour sortersoperate at 2-3 bar range.

R9.The norm is to run the compressors at thelowest pressure to match the system need.Any additional increase in 1 bar will increaseenergy consumption around 8%. So operatethe compressors at 4-7 bar range.



Estimated Investment :Nil

SPP :immediate

OB10.

The colour sorters are running withthree separate reciprocating compressorsand their loading time is less than 25%.

R1.

Connect the two tanks of Meiji compressorsto the Hansi compressor and operate the allcolour sorter with it while keeping the Meijicompressors standby.



Estimated Investment :Nil

SPP :immediateR10. OR

Introduce a screw compressor with 1500liters/ minute coupled with an air dryer andan air receiver and operate at 4-6 bar range.


Expected Annual Saving: LKR 106,400.00Estimated Investment :LKR 700,000.00

SPP :6 Years

7.1.5 Main Panel

As per the Graph No 12, factory has sudden electricity peaks (as indicated in the Graph). The

peaks could be attributed to followings;

1. Sudden on and off of heavy motors due to operational changes in the process

2. Frequent power interruptions of the national supply

3. Workshop operations during the process peak time

4.

Poor power quality (high fluctuations in the supply voltage) from the National grid supply

Comment [S45]: I think a better language wobe

Reduce the pressure settings of xx, yy and zzreciprocating type compressors from the currentsettings of xxx to yyy.

Comment [l46]: Changed

Comment [S47]: Receiver?

Comment [l48]: Changed to Receiver tank


41/56




As indicated in Graph 13, the grid supply has a large variation. This variation is exceeding the

5% of allowable limit. The indicated area has a variation above 10%. This is due to the factory

location which is at the extreme end of the supply line.

0

20

40

60

80

100

120

140

16:15

17:00

17:45

18:30

19:15

20:00

20:45

21:30

22:15

23:00

23:45

0:30

1:15

2:00

2:45

3:30

4:15

5:00

5:45

6:30

7:15

8:00

8:45

9:30

10:15

11:00

11:45

12:30

13:15

14:00

14:45

15:30

16:15

kW/kVA

Time

kW kVA

205

210

215

220

225

230

235

240

245

16:15

17:00

17:45

18:30

19:15

20:00

20:45

21:30

22:15

23:00

23:45

0:30

1:15

2:00

2:45

3:30

4:15

5:00

5:45

6:30

7:15

8:00

8:45

9:30

10:15

11:00

11:45

12:30

13:15

14:00

14:45

15:30

16:15

V

Time CH 01 (V) CH 02 (V) CH 03 (V)

Graph 1011: Load Variation during a Day Operation

Graph 1112: Voltage Variation of the National Grid Due to Poor Power Quality


42/56




Table 17:Observation & Recommendation for Main Panel


OB11.Sudden peak load due to rapid on andoff of high capacity motors.

R11. Enhance the awareness of employees onthe maximum demand variation.

This will contribute to reduce the sudden

peaks in the maximum demand. For an

example turning all the machineries at

once after a power interruption.

OB12.The panel does not have sub meteringfacilities.

R12. Introduce separate breakers for keysections along with electricity meters andconnect to the sub breakers and record the

sectional power consumption daily.Estimated Investment :LKR 350,000

This is contributing to work towards

energy saving in future

OB13.

Absence of automatic synchronouschange over for the generator and CEBsupply. Thus sudden maximum demandincrease in the during the powerinterruptions.

R13. Introduce a automatic synchronouschange over for the generator

Expected Energy saving :240 kVA

Expected Annual Saving: LKR264,000.00

Estimated Investment :LKR 400,000.00

SPP :1.5 Years

OB14.20m x 20m roof space is available inthe factory premises

R14. Introduce a 50 kW net metered solarpower system for the premises.

Expected Energy generation: 72,000 kWhExpected Annual Saving:LKR100,800.00

Estimated Investment:LKR10 M

SPP : 9 Years

Comment [S49]: Could you not suggest someschedules as to how they should do this ? or havetraining ?

Comment [l50]: Included

Comment [S51]: How ? needs furtherexplanations


Comment [S53]:Needs further explanation ahow the change over would work and how it wouact during power interruptions as compared to thecurrent situations.

Comment [S54]: Very less explanation. Thisshould be dealt with under a separate section calleonsite renewable energy ( or something similar) .Details on technology, PV specifications, inverterspecifications and probably a block diagram / sinline diagram needs to be provided.

One also has to make sure that the roof is structurstable to hold the system and that for a particularorientation of the solar PV system, what would beeffect of shadows etc due to trees and other objecFor an investment of 10 M LKR dedicating just 23 sentences is not sufficient at all



43/56




7.2

Thermal

7.2.1

Withering Section

Table 18: CFM Details of the Withering Troughs

Trough

No

Total

CFM (closed

hot air

damper)

Hot Air

Temperat

ure (C)

Hot Air

rH (%)

CFM (after

opening the

Hot Air

damper)

Hot air

CFM

Remarks

1 26,000 47.3 32.9 16,000 10,000

2 20,000 50.4 28.6 12,500 7,500

3

24,000 50.9 28.1 12,000

12,000 Motor is

Vibrating

4 16,000 46.2 33.6 11

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