of 'Black-box' Models in Power Plant Flowsheets Optimization and ...

Optimization and Integrationof ‘Black-box' Modelsin Power Plant FlowsheetsYidong Lang & Lorenz T. BieglerDepartment of Chemical EngineeringCarnegie Mellon UniversityEnergy System Initiative4/23/10 12:02March 7, 20101

OutlineMotivationDevelopment of ROMWrapped yROM for flowsheetIntegration of ROM into Flowsheet in GAMSOptimization and Closed loop evaluationConverting yROM into USER3 modelIntegrating the USER3 with IGCC in AspenPlusfor further Optimization with EO mode4/23/10 12:022

Concepts of APECS:Co-Simulation with Aspen Plus and FluentCFD Model4/23/10 12:023

Road map from CFD model to“Black box” modelDevelopedROMFlowsheet of IGCC inAPECS with AspenPlus and Fluentaccommodating CFDModelExtractedCFDmodelDevelopedUSER3 ModelAccording tothe protocolsin Aspen PlusFlowsheet of IGCC in Aspen Plus withreplacement of USER3 of ROM whichcan be optimized with EOEquations of ROMinserted part ofIGCC flowsheet inGAMS4/23/10 12:024

ROM Development for CFD ModelROM is a remedy to overcome CPU time prohibited of CFD model in iterativecomputing of co-simulated flowsheet simulation and optimization1. Determine operation domain, Experimental design (LHS)2. Run Fluent cases according to the results of Experimental designCases ofCFDModelPCAROMxROMDisplay fields of statesafter convergenceyROMFor Iterative processsimulation and optimization4/23/10 12:02Ref: Lang et al., Reduced Order Model Based on Principal Component Analysis forProcess Simulation and Optimization†, Energy & Fuels 2009, 23, 1695–17065

Development and Validationof ROM for GasifierThe predicted effect of inputs on outlet temperature given byyROM shows reasonable reliability4/23/10 12:02split6

Wrapping yROM of Gasifier asa section of flowsheets81Interfaces41GFposts82Gasifiers87s83WaterMixer 2s85s88SplitterCoals84Mixer 1s864/23/10 12:02Oxyg.s897

Integration yROM ofGasifier and Steam CycleFUELS 41GasTurbineS 40S 42S 46S 39AIRS 43S 45HRSGS 47S 54S 15S 20S 1 S 58High Pressure ( HP )HeaderGasifierS 2S 5S 59S 60Medium Pressure ( MP )HeaderS 12S 3S 4S 6S 7S 61Low Pressure ( LP )HeaderwaterCoalO2S 16S 34 S 35 S 36CW4/23/10 12:02DWS 17DeaeratorS 11HPCONS .S 9MPCONS .LPCONS .S 37 S 10 S 38CondensateHeaderS 8Vacuum Header8

Optimal SolutionMinimizing Objective Function Subject toPower Demand (Net Electricity): 500 MWObjective FunctionAdd. ConstrOptimal solutionsu1 u2 u31 Heating Value of Syngas No 84.6928 34.9266 84.88132 Coal Feed flowrate No 70.3411 25.2085 75.21543 Heating Value of Syngas Tout >1660Tout < 16704 Coal Feed flowrate Tout >1660Tout < 167084.6928 34.9266 82.71619870.3411 25.2085 75.9128134/23/10 12:029

Results of closed looptest for yROMH2S H2O H2 CH4 CO2 CO Temp(K)Loop test(1)ROM 0.013172 0.305403 0.011566 0.025022 0.067842 0.552102 1709.19Fluent 0.013149 0.305228 0.011611 0.024865 0.069569 0.550176 1712.65Error(%) 0.17 0.06 0.38 0.63 2.48 0.35 0.20ROM 0.015087 0.207855 0.017510 0.031057 0.065993 0.635727 1644.08Loop test(2)Fluent 0.015114 0.206340 0.017904 0.030502 0.065742 0.638125 1627.54Error(%) 0.18 0.73 2.20 1.82 0.38 0.38 1.02ROM 0.013277 0.304384 0.011538 0.027482 0.061432 0.557007 1670.00Loop test(3)Fluent 0.013280 0.302956 0.011573 0.028183 0.065889 0.552833 1667.49Error(%) 0.02 0.47 0.30 2.49 6.76 0.76 0.15Loop test(4)4/23/10 12:02ROM 0.015042 0.206258 0.017836 0.029846 0.073121 0.631096 1660.00Fluent 0.015602 0.211528 0.016875 0.031671 0.063249 0.635083 1657.04Error(%) 0.13 2.49 5.69 5.76 15.61 0.63 0.1810

Closed Loop (1) for xROM4/23/10 12:0211

Closed Loop (3) for xROM4/23/10 12:0213

Closed Loop (4) for xROM4/23/10 12:0214

Converting yROM intoUSER3 model in Aspen Plus4/23/10 12:0215

IGCC flowsheet and integrationof replaced CFD modelGas-Combustor-TurbineSteam cycleWater shiftTSA and CO2 compression4/23/10 12:0216

ConclusionsThe concept of APECS is extended to process optimization byreplacing CFD model with its PCA ROM in IGCC flowsheetROM for gasifier is developed and validated‘Closed loop’ tests in GAMS show that validation from convergedFluent case is encouraging.Conversion from yROM into USER3 model is successfullyimplemented and can be integrated with an existing IGCCflowsheetWe are now aiming at EO mode of the simulator, it is potentiallypossible to used novel NLP solver like Ipopt in processoptimization for IGCC4/23/10 12:0217

Future WorkROM of Gas turbine combustor will be developed following theprocedures of PCA ROMConvert its yROM into USER3 in Aspen Plus and integrate withIGCCImplement optimization with integrated two ‘Black-box’es usingEO and open solver in Aspen Plus4/23/10 12:0218