dynamic optimization of profit and olefin production … optimization in an ethylene plant dynamic...

2004 Users Group Americas Symposium • Partners in Innovation0

Dynamic Optimization in an Ethylene Plant

Dynamic Optimization of Profit and Olefin Production using Profit Controller and Profit Optimizer in Ethylene Plant

Byoungmin Lee, Sungchul Yoo, Changhun Kang and Howoo Lee LG Petrochemical Corporation Ltd.Sung-Mo Ahn and Ravi NathHoneywell Process Solutions



Contents

Introduction of CompanyProject OverviewProject ProgressAPC & DQP DesignBenefits AchievedConclusions



Company History

1978. 3 Established LG Petrochemical CO., Ltd.1991. 9 Dedicated Naphtha Cracking Center1992.10 Dedicated Aromatics & HDPE Plant1993.11 Acquired ISO 9002 Certification of HDPE Plant (DNV)1994. 5 Dedicated Pentane Plant1996. 8 Revamped NCC & HDPE Plant1997.12 Acquired ISO 14001 Certification1998. 9 Revamped BTX Plant 2000.12 Acquired Korea Energy Grand Prize



Company Overview• Paid-up Capital • Employees • Annual Sales • Plant site • Business Activities: Manufac

: 226 KRW bn: 554 (As of Apr.2003): 1,286 KRW bn (in Fiscal Year of 2003): 462,043㎡ (In the Yeosu petrochemical complex)

turing,Selling and Purchasing ofPetrochemicals,Utilities and Electric Power



Products and Capacity

NaphthaC4 LPGGas Oil

NaphthaCracking Center

(Unit : 1,000MT/YR)HDPE Plant Ethylene 750 HDPE 265

Propylene 370

C4 LPG

Butadiene 118Raffinate-1

Butadiene/ C4 HTU

Plant Mixed C4

Toluene 85Benzene 200

Aromatics Plant

PyrolysisGasoline Xylene 42

Mixed-C5

High Purity Pentane 20C5 Plant



Petrochemical Business of LG GroupAccomplished the perfect vertical integration from oil refining to production of a large variety of petrochemical products.

(Unit : 1,000MT/YR)

Vertical integration

• Basic Petrochem 1,565- Ethylene- Propylene- Butadiene- BTX

• Polymers 265- HDPE

• Naphtha • Monomer 2,200- VCM- SM- MMA …

• Polymers 2,280- PVC- ABS- LDPE …

LG LG -- CaltexCaltex OilOil LG LG PetrochemPetrochem LG LG ChemChem



LG’s Participation in Yeosu Complex

Production Amount Employees

LG72%(15.6)

LG Petrochem

100%(21.6 trillion won)

LG28%(3,600)

3.8%(470)LG Petrochem

100%(12,600 employees)

5%(1.1)



Vision

To be a world class petrochemical company growing with our customers by creating differentiated value

Vision

• Trust & Teamwork• Challenge & Breakthrough• Abiding by Principles

Shared Value

Management Policies

• Enhancing the talents of each employee• Development of core technologies• Implementation of Cash flow-oriented management



Goal & Strategy for Existing BusinessGoal Strategy

2000 2005

1,0741,262

91133

CAGR3.5%

CAGR7.9%

(Unit : KRW bn)

Sales

OrdinaryIncome

• Achievement of the world’s best cost competitiveness

• Implementation of strategic new business and high-value-add by-product business

• Development of core technologies

NCC

• Development of specialty products and increase of sales ratio of specialties

• Achievement of cost leadership• Pursuit of M&A and strategic

alliance to promote competitiveness

HDPE

☞ CAGR : Compound Annual Growth Rate



Goal & Strategy for New Business – BPA(Bis Phenol A)

▶ S Korea S/D balance ▶ Asia S/D balance, ex-JPN

PhenolAcetone

BPA

PhenolAcetone

BPA

Benzene: 160,000 tons/yearPropylene: 87,000 tons/year

35

135 135

259

201

127

2001 2003 2005

CapaDemand

Demand CAGR 16.3%

Demand CAGR 16.3%

1,155

600

1,188

651

2002 2007

CapaDemand

Demand CAGR 11.3%

Demand CAGR 11.3%

< Valuation >

• Capex : W200bn

• Coming out 1Q05

• Feasibility : IRR 19.5%, sales W205bn

• Expected operating income: 30%

Cumene: 240,000 tons/yearCumene: 240,000 tons/year

Phenol/Acetone: 180,000 tons/yearPhenol/Acetone: 180,000 tons/year

BPA: 120,000 tons/yearBPA: 120,000 tons/year

NCCNCCLG PetrochemicalLG Petrochemical

PolycarbonatePolycarbonateLG-DOWLG-DOW



Core Competence

Ethylene production capacity(1,000MTA/YR)

850750

(754)

385

600Revamping

(150)

Capacity up : 195%

20061996 20011992



Core Competence Specific energy consumption

(Kcal/kg,Ethylene)

6,130

5,3504,649

3,990

World best level

1996 20011992 2005



Innovation Activities

Enterprise Resource Planning

SKILL (Problem Solving Process )

Six Sigma

2001

Responsible Care Knowledge Management Systeme - Trading

e – Procurement

1992 1994 1999

Total Productivity Management

11 / 11



BA101

Ethane Recycle

Naphtha

BA102

BA103

BA104

BA105

BA106

BA107

BA108

BA109

BA110

BA111

BA112

BA113

BA114

BA115

BA101 : Ethane- onlyBA102/111 : Co- crackingBA112/113 : Split- cracking

EthaneEthane

EthaneEthane

Ethane

DA101

Fuel Oil

DA104

DA207

DA202

DA401

DA301

DA402

FF201

DA404/414

DA406/407

GB201

GB601 GB501

C2H2 Conv.

H2, CH4

DA415 MAPD

Conv.

C2H4

C3H6

C3 LPG

RPG

Manual

Manual

DA101 : Gasoline Fractionator GB201 : Charge Gas Compressor DA402 : Ethylene FractionatorDA104 : Quench Tower DA301 : Demethanizer DA404/ 414 : Depropanizer No.1/ 2DA207 : Dryer Feed Wash Tower DA401 : Deethanimzer DA415 : Depropanizer No. 3DA202 : Condensate Stripper GB501 : C3- R Compressor DA406/ 407 : Propylene FractionatorE- FF201 : Charge Gas Dryer GB601 : C2- R Compressor DA405 : DebutanizerDA201: Gasoline Stripper

DA201

DA405

Mixed- C4




Dynamic Optimization in an Ethylene PlantDynamic Optimization in an Ethylene Plant

PROCESS CHARACTERISTICS• Significant feed quality variations• Furnace decoking• Periodic operations (e.g. dryer switching)• Others

Filter plugging, catalyst breakthroughAmbient condition variations

Process is very dynamic, seldom steady !




APC History1st implementation by the E&C Company

• Not successful becauseStead state optimizer,

– Maintenance issueProcess seldom steady,

– Infrequent optimizationOverall low benefits, high maintenance cost

Still convinced of the benefits decided to give it a second try in 2000




Current APC projectKicked off in March 2000 with the following objectives

• Stabilize fractionators operation• Energy Savings • Increase Olefins production• Develop internal expertise




Solution Technology SelectionConsidered all available offerings, and chose Honeywell

• Robust controller• Simpler controller tuning• Ease of adding optimization layer• Dynamic Optimization• Local support




Project TeamComposed of limited internal resources and Honeywell staff

• LGPC resources has actively taken part in

LGPCProject Manager

HoneywellProject Manager

LGPC EngineersLGPC Engineers

Team



Project Progress (1)2000 - 2003

• Training of in-house staff• Cold side controllers to stabilize column operation

Step testing, model identification and commissioning of the following;– Demethanizer / C2 Refrigerant– Deethanizer– Ethylene fractionator / C3 Refrigerant– Depropanizer– Propylene fractionator




Project Progress (2) Sept. 2003

• Attention shifts to hot side control Step testing, model identification and commissioning of the following;

– 1 Ethane only heater– 11 Naphtha only heaters– 2 Naphtha and ethane co-cracking heaters– 1 Ethane and naphtha selection heater




Project Progress (3) Nov. 2003 – March 2004

• Attention shifts to dynamic optimizer On-line execution of customized furnace yield model

– for calculation of severity and yield gainsSeverity gain mapping Closing of 2 still open loopsBridge Model identificationProfit Optimizer

– configuration / gain updating / closed loop commissioning




System configuration

PHD(Database)

Custom HTR model Cold section APC

Hot section APC

GMPC toolkit

GEMPO toolkit

Pre_dqp

Profit Optimizer

TCP/IP Network

LCN

APP 23Workstation forcustomized heater model

US/GUS

APP 25




Profit Controller Overview




Graphical User Interface


• Profit Viewer for Engineer / User Station standard graphics for Operator




Profit Controller Design(1)

Hot section• Typical controlled variables

Severity or conversionTube outlet temperatureCross over temperatureValve positions

• Typical manipulated variables Coil outlet temperatureFeed flow rateSteam to HC ratio




Profit Controller Design(2)

Cold section• Typical controlled variables

Overhead purityBottom purityCompressor speedDischarge pressurePressure differenceTray temperatureValve positions

• Typical manipulated variables Steam flow rateReflux flow rateSide draw flow ratePressure




Customized Heater Model Design (1)• Step testing, model identification and commissioning of 15 heaters• Customized Heater Model was developed by internal resources.

SCM

Stand AloneStand Alone

PISNIR,…

DCS



Customized Heater Model Design (2)



Pre_DQP for Customized Heater Model



Profit Optimizer Design(1) One for all controllers

• 15 Hot section controllers• 6 Cold section controllers• 4 Dummy controllers

More than Summation• 9 Bridge models• 39 Combined constraints



Profit Optimizer Design(2) Bridge model

• Dynamic model between column feed and heater MV• Dynamic model between olefin production and heater MV • Obtained from step test and historical operation data

Combined constraint model• Total hydrocarbon flow• Furnace yield and overall propylene / ethylene ratio• Coking rates• Total fuel consumption and total steam generation



Profit Optimizer Design(2) Bridge model



Benefits achieved (1):Cold side controllers : Ethylene fractionator



Benefits achieved (2):Cold side controllers : Ethylene fractionator

Comparison ethane composition of ethylene product before APC with after APC

The Productivity Increasment of ethylene fractionator after APC application



Benefits achieved (3):Cold side controllers : Depropanizer



Benefits achieved (4):Cold side controllers : Deethanizer & Depropanizer

The Energy savings of deethanizer after APC application

The Energy savings of depropanizer after APC application



Benefits achieved (5):Cold side controllers : Benefits Summary



Benefits achieved (6):Cold side controllers : Operator satisfaction



Benefits achieved (7):Dynamic Optimization : Constraint handling

2004 Users Group Americas Symposium • Partners in Innovation



Benefits achieved (8):Dynamic Optimization : Olefin maximization trend




Benefits achieved (9):Dynamic Optimization : Comparison before DQP with after DQP



Benefits achieved (10):Dynamic Optimization : Comparison before DQP with after DQP

Stabilization & about 0.4% Increase ofOlefins Production and Naphtha Feed



CONCLUSIONS• APC and dynamic optimization of the entire Olefins plant

Using limited internal resourcesSome consultation from Honeywell

• Sustained APC and optimization benefitsstabilized plant operation with all loops closeduptime > 95%olefins production increase of 0.97% (1.25T/hr)

• Now considering other measures of productivity improvement Automation of furnace transientsASMOperator training



dynamic optimization of profit and olefin production … optimization in an ethylene plant dynamic...

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