Energy Efficiency Hierarchy Evaluation based on DE

EnergyEfficiencyHierarchyEvaluationbasedonDEAanditsapplicationinEthyleneProductionProcessZhiqiangGeng†,YongmingHan†,JiqinZhu‡†CollegeofInformationScienceandTechnology,BeijingUniversityofChemicalTechnology,Beijing100029,China‡StateKeyLaboratoryofChemicalResourceEngineering,BeijingUniversityofChemicalTechnology,Beijing100029,ChinaAbstract:Dataenvelopmentanalysis(DEA)hasbeenwidelyusedintheenergyefficiencyanalysisofenterprisedevice,buttoomuchdecision-makingunitsofDEAmodelareeasytocausethatmoredecision-makingunits’efficiencyvalueare1,aswellascannotdistinguishtheprosandconsoftheeffectivedecision-makingunits.ThispaperproposesaDEAintegratedanalytichierarchyprocessmode(AHP)methodtoovercomeshortcomingsmentionedabove,whichnotonlyisabletosolvetheproblemoftoomucheffectivedecision-makingunit,andalsobeabletomoreeffectivelyreflectthedecision-makinguniteffectivenessamongthedifferentlevels.Thesmallnumberofdecision-makingunitsisanalyzedusingDEAmodel,andthemulti-levelintegrationofDEAefficiencyvaluesweredisposedusingAHPmethod.Themethodisappliedtotheenergyefficiencyanalysisofethyleneproductionprocessbasedonanalysismonth,yearanditsindustry-levelofethyleneplantunderdifferenttechniquesanddifferentscales.Itcanguidetheethyleneproductionsystemtoreducetheenergyconsumptionandimproveenergyefficiencies.Keywords:ethyleneproductionprocess;energyefficiency;dataenvelopmentanalysis;analyticTowhomcorrespondenceshouldbeaddressed:E-mail:[e-mail]@mail.buct.edu.cn,Tel:[phone],Fax:[phone]hierarchyprocess1.IntroductionBeingtheleadingofpetroleumchemicalindustry,theethyleneproductionleveloftenservesasoneofthemainsignalstojudgetheindustrydevelopmentlevelofacountry.Inrecentyears,energyconservationandemissionreductionisoneofthetoptopicsfocusedonbyallcountriesintheworld.Energy-savinghasbeenapoliticallawtobewritteninnationaldevelopingstrategyinmostcountries.In2008,accordingtostatistics,theethyleneproductioncapacityofSinopecCorporationis6359.4Ktandtheethyleneplantenergyconsumptionis649.36Kg/tstandardoil1.Similarly,thoseofPetroChinaCompanyLimitedare2676Ktand714Kg/tstandardoil,respectively2.Theirenergyconsumptionisfarlowerthanthatoftheadvancedlevelabroad,whichmeansthatethyleneindustryinChinahasgreatimprovementspaceforenergyefficiency.Theenergyconsumptioncosttookupmorethanhalfoftheoperationcostinethyleneproductionequipment3.Thus,researchesaboutitsenergyefficiencyevaluationhavegreateconomybenefits.Currently,enterprisecommonlyusesthemeanmethodandoptimalindexmethodtoanalyzeenergyefficiency4.Sinceenergyefficiencyvaluecontainsbothindicatorsandinfluencingfactors,thevalueofvariousfactorshasdifferentmeaningtoenergyefficiencyindicators,andthemeanmethodandoptimalindexmethodconnotintroduceenergy-savingknowledgeintoenergyefficiencyanalysis,whichcannotbegiventoenergyefficiencybenchmarkofvariousfactorsandexcellentindicatorstoguidetheactualstateofenergyefficiencyanalysis.Gengetc.proposedtheenergyconsumptionanalysismethodofethyleneplantbasedondatafusion,obtainedabettereffect,butdidnotconsidertheimpactfactorsofenergyconsumptionindicators5,6.InallusiontodisadvantagesofexistedenergyefficiencyevaluationofethyleneindustryinChina,thepaperspecificallyproposesthemethodcombiningdataenvelopmentanalysis(DEA)withanalytichierarchyprocess(AHP)toevaluateenergyefficiencyofethyleneproductsystemIn1978,thefamousoperationresearchersA.Charnes,W.W.CooperandE.RhodeshavefirstlyproposedDEA.Theyusedthismethodtomake‘productionapartment’,whichhadmultipleinputs,especiallymultipleoutputs,both‘sizeableeffective’and‘technologicaleffective’.Thisapplicationturnedouttobemuchsatisfactoryandeffective7.AHP(analytichierarchicprocessmode),whichcombinesqualitativewithquantitativeanalysis,isahierarchicalandmulti-criterionanalyticmethod8-11.Itmeetswiththerequirementofmultiplesolutionsfusionundermultiplecriteriaofhierarchicalmodeofenergyefficiencyvalue.Wuetc.researchedonEvaluationModelofEnergyEfficiencyBasedonDEA12.JablonskyandJosefstudiedontwooriginalmodelsforrankingofefficientunitsinDEA-theyarebasedonmultiplecriteriadecisionmakingtechniques-goalprogrammingandAHP13.YanandCuigavearelativelyreasonablesequencingmethodforaclassofmultifactorsequencingproblembycombiningAHPwithDEA14.Ehsanetc.studiedenergyconsumptionefficiencyforcornproductionutilizingDEAandAHPtechniques15.Diegoetc.proposedalogisticsproviderevaluationandselectionmethodologybasedonAHP,DEAandlinearprogrammingintegration16.TheauthorstudiedrespectivelyusingthemodelofDEAandAHPtoevaluateenergyefficiencyofethyleneproductsystem17,18.First,thepaperusesDEAtoanalysisefficiencyvalueofthemonthdatafordifferentdevicesunderthesametechnologyinacertainyear,andobtainstheenergyefficiencyoftheethyleneproductionequipmentatthesametimefindstheimprovementdirectionofthenon-effectivedecision-makingunits.ThenthemonthlydataofethyleneproductionenergyefficiencyfromthesametechnologywasweightedfusedbyAHP.Finally,theyeardataofethyleneindustryandenergyefficiencydatafromdifferenttechnologieswereevaluatedtheirrelativeeffectivenessbyDEA.Thismethodisus