简介:Fordealingwithhigh-salinitywastewaterintherefinery,thehighcostofdrivingheatsourceisthedisadvantageofmulti-effectdistillation(MED)soitisofgreatimportancetoevaluatetheperformanceoflow-temperatureheatsourceforconductingMEDandselecttheoptimaltemperatureforit.BoththeMEDandthelow-temperatureheatsourcesstudiedinthispaperwerefromatypicalrefinerylocatedinnorthwesternChina.Besides,anewmethodologytoevaluateheatsourcesastheoptimalcandidatewasproposedforMEDbasedonthegreysystemtheory.Fiveprocessunits,whichincluded18fluidsoftherefinery,werenamedastheevaluationprojects.Threefactors,whichincludedsafetyeffects,totalcostsandcharacteristicsoflow-temperatureheatsourcesweredeterminedastheevaluationindexes,thevaluesofwhichwereestablishedthroughtheanalyses.Theresultsobtainedthroughthegreycorrelationanalyseshaverevealedthatthegreycorrelationdegreesoftheseunitswere0.661(AVDU),0.732(#1FCCU),0.618(#2FCCU),0.535(#1DCU),and0.572(#2DCU),respectively.Thus,theoptimalheatsourcewasprovidedfrom#1FCCU.Throughfurtheranalysesofthefluidsfrom#1FCCU,thegreycorrelationdegreesofthefluidswere0.597(oilandgasattopoftower),0.714(recycleoilandgas),and0.512(diesel),respectively.Thus,theoptimalheatsourcewastheoilandgasrecyclestream.