oil stab op tim ization

Post on 06-Mar-2016

27 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

DESCRIPTION

Oil Stab Op Tim Ization

TRANSCRIPT

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 1

    OilStabilizationOptimization

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 2

    Workshop A poor-boy stabilization scheme is used to separate an oil and gas mixture into a stabilized oil and a saleable gas. A simple three-stage separation with heating between each stage is used and the object of the exercise is to select the let-down pressure and temperatures such that the products revenue less the utilities cost is maximized. A special tool in HYSYS, the Optimizer, will be used to find the optimum operating conditions. HYSYS includes additional modelling and decision support tools that can be used to enhance the usability of your models. In this module, you will use the HYSYS optimization tool available in HYSYS to investigate the debottlenecking and optimization of a crude column. Learning Objectives Once you have completed this section, you will be able to: Use the Optimizer tool in HYSYS to optimize flowsheets Use the Spreadsheet to perform calculations

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 3

    OilStabilizationAfeedstream@10oC,4125kPawithaflowrateof1MMSCFDisfedtoaheater (duty=4.25*105kJ/hr)beforeentering the first separatorwheretheseparated liquid isheated inasecondheater(duty=3.15*105kJ/hr).Theoutlet from theheater is thensent toa letdownvalve inorder todecreasethepressureto2050kPabeforeenteringthesecondseparatorwheretheseparatedliquidisheatedthroughathirdheater(duty=1.13*105kJ/hr).Theoutletfromthethirdheateristhenthrottledthroughavalve(outletpressure=350kPa)andthenfedtoathirdseparatortoobtainthefinalliquidoilproduct.Each gas stream from the 2nd & 3rd separators is fed to a separatecompressor to raise thepressure to4125kPaand thenmixed (usingamixer)with thegas stream from the 1st separator toget the finalgasproductstream.Notes:

    Pressuredropacrossallheatersandseparatorsare0.0.Calculate:

    Thetotalliquidproduct=barrel/hr Thetotalgasproduct=m3_gas/hr

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 4

    OilStabilizationOptimizationIn this case, we want to maximize the total operating profit whileachievinganRVPofLiquidProductlessthan96.5kPa.TheincomesfromthePlantareboththeGasandLiquidProducts.Theoperatingcostsarethe Steam Costs for each Heater plus the Power Cost for eachCompressor.Profit=IncomeCost Profit=(GasProduct+LiquidProduct)(SteamCosts+CompressionCost) Prices&costs:OilPrice=15$/bblGasPrice=0.106$/m3_gasSteamCost=0.682$/kWhCompressionCost=0.1$/kWhThevariablestobeadjusted:

    Heaterduties(forthe3heaters).Userangeof01e6kJ/hr Valvesoutletpressures.

    Userangeof6503500kPaforthefirstvalveUserangeof701000kPaforthesecondvalve

    Calculate:

    Theoptimumvaluesfortheadjustedvariables Themaximumprofit..$/hr

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 5

    Tostarttheprogram,FromStartMenu,SelectAllPrograms>>AspenTech>>ProcessModelingV8>>>>AspenHYSYS>>AspenHYSYS

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 6

    1- First, Start a new case

    2- Add the Components

    3- Choose the system components from the databank:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 7

    Now, select the suitable fluid package

    In this case, select Peng-Robinson

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 8

    Now you can start drawing the flow sheet for the process by clicking the Simulation button:

    Now add a material stream to define the feed stream composition and conditions

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 9

    From the palette:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 10

    Addaheaterwithadutyof4.25*105kJ/hrandpressuredropof0.0

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 11

    Addthefirstseparator

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 12

    Theliquidstreamisthenheated,addasecondheaterwithapressuredropof0.0&dutyof3.15*105

    Addavalvewithoutletpressureof2050kPa

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 13

    Addthesecondseparator

    Theliquidfromthesecondseparatorisnowfedtoathirdheaterwithapressuredropof0.0&dutyof1.13*105

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 14

    Addasecondvalvewithanoutletpressureof350kPa

    Addthethirdseparator

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 15

    Thevaporfromthesecondseparatorisfedtoacompressortoraisethepressureto4125kPa

    Addacompressorfromthepalette

    Thevaporfromthethirdseparatorisfedtoasecondcompressortoraisethe

    pressureto4125kPa

    Addasecondcompressorwithanoutletpressureof4125kPa

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 16

    Thethreevaporstreamswillbemixedusingamixer

    TheRVPoftheLiquidProductstreamshouldbeabout96.5kPatosatisfythe

    pipelinecriterion.

    UsecoldpropertiesanalysistoseethecurrentReidVaporPressurefortheliquidproductfromthethirdseparator:

    Fromtheattachmentstab,selectAnalysisandthenCreate:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 17

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 18

    ChangingtheUnitsWeneedtochangethedefaultunitsettofitthiscase

    Changetheunitsasfollows:

    Molarflow:m3_gas/hr

    Liq.Vol.Flow:barrel/hr

    Std.Vol.Flow:barrel/hr

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 19

    OptimizationHYSYS contains amultivariableSteadyStateOptimizer.Once your flowsheethasbeen built and converged, you can use the Optimizer tool to find the operatingconditionswhichminimizeormaximizeanObjectiveFunction.TheOptimizerownsitsownSpreadsheet fordefiningtheObjectiveFunctionsaswellasanyconstraintexpressions to be used. This allows you to construct Objective Functions whichmaximizeprofit,minimizeutilitiesorminimizeexchangerUA.

    Inthiscase,wewanttomaximizethetotaloperatingprofitwhileachievinganRVPofLiquidProductlessthan96.5kPa.TheincomesfromthePlantareboththeGasandLiquidProducts.TheoperatingcostsaretheSteamCostsforeachHeaterplusthePowerCostforeachCompressor.Profit=IncomeCost Profit=(GasProduct+LiquidProduct)(SteamCosts+CompressionCost)

    UsetheOptimizertool:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 20

    Thevariablestobeoptimizedinordertomaximizetheprofitshouldbeaddednow,thesevariablesare:

    The3HeatersdutiesandValvesoutletpressures

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 21

    Afteraddingallthe5variables,settheupperandlowerrangesforeachvariableasfollows:

    TheOptimizerhasitsownSpreadsheetfordefiningtheObjectiveandConstraintfunctions.

    Nowwehavetostartbuildingtheprofitmoduleusingthespreadsheetoperation:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 22

    Profit=IncomeCostProfit=(GasProduct+LiquidProduct)(SteamCosts+CompressionCost) Prices&costs:OilPrice=15$/bblGasPrice=0.106$/m3_gasSteamCost=0.682$/kWhCompressionCost=0.1$/kWh

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 23

    TheRVPspecfortheliquidshouldbeaddedinthespreadsheetinordertouseitasaconstraint.RVPspec=96.5kPaFirstweneedtoincreasethenumberofrowsinthespreadsheettobe20fromtheparameterstab:

    Nowreturntothespreadsheettabagainandaddalltheprofitequationparameters&variables.

    Afteraddingthelabels,importthevariablesineachlabeledcell:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 24

    Addalldutiesforheaters&compressorsthesamewayaswedidinthepreviousstep.

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 25

    DothesameforOil&gasproductionflowrates

    TheRVPcurrentvalueshouldbeimportedfromtheAnalysis:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 26

    ThePricesshouldnowaddedmanuallywithoutimportingit

    CalculatetheIncome,Cost&Profitusingthecurrentformulas:

    Income:=d7*b7+d8*b8

    Cost:=(b1+b2+b3)*d1+(b4+b5)*d4

    Profit:=d12d13

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 27

    Aftercalculatingtheoperatingprofit@currentconditions,usethe

    optimizertomaximizetheprofitbychangingthe5variableswhichweaddedbefore

    OpentheoptimizerandgotoFunctionstab:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 28

    YoumayneedtopresstheStartbutton2or3timestoensurereachingtheoptimumsolutionasfollows:

    YoumayseethenewvaluesforthevariablesfromtheVariablestab:

    Nowyoucanreturnbacktothespreadsheettoobservetheresults:

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 29

    SaveYourCase!

  • Optimization

    By:Eng.AhmedDeyabFareshttp://www.adeyab.com Mobile:00201227549943Email:eng.a.deab@gmail.com 30

    Exercise:

    OnethingyoumaynoticewiththeOptimizedsolutionisthatthePressureof V3 has been decreased to 70 kPa (10 psia) which is less thanatmospheric.Thisisnotadesiredconditionfortheinletofacompressor.Theinletofthesecondcompressor,cannotbelessthan125kPa(19psia).Whatisthemaximumprofitifyouadheretothisguideline?

top related