简介:Thesorption-enhancedsteamreformingprocessofmethanol(SESRP-MeOH)toproducehigh-purityH2wasthermodynamicallyandexperimentallystudied.ThermodynamiccalculationsshowedthatataCO2adsorptionratioof95%,productgascontains98.36%H2,32.8ppmCOundertemperatureof130°Candsteam-to-methanol(S/M)molarratioof2.However,withoutadsorption-enhanced,theproductgascontainsnearly74.99%H2with24.96%CO2and525ppmCO.Toverifythethermodynamiccalculationresults,experimentswereperformedinafixed-bedreactorloadedwithcommercialCuO/ZnO/Al2O3methanolreformingcatalystand22%K2CO3-promotedhydrotalciteasCO2adsorbent.Experimentalresultsshowedthat99.61%H2couldbeobtainedbySESRP-MeOHatreactiontemperatureof230°CandS/Mof2.UnderthesameCH3OHconversion,thereactiontemperaturedecreasedbyalmost50°CandH2concentrationincreasedofmorethan20%usingSESRP-MeOHcomparedwithsolelysteamreformingofmethanol.Thecharacterizationoftheadsorbentandcatalystshowedthattheadsorbentshowedgoodstabilitywhilethecatalystwasseriouslysinteredunderthehighregenerationtemperatureoftheadsorbent.
简介:Thesteamreformingoffourbio-oilmodelcompounds(aceticacid,ethanol,acetoneandphenol)wasinvestigatedoverNi-basedcatalystssupportedonAl2O3modifiedbyMg,CeorCointhispaper.Theactivationprocesscanimprovethecatalyticactivitywiththechangeofhigh-valenceNi(Ni2O3,NiO)tolow-valenceNi(Ni,NiO).Amongthesecatalystsafteractivation,theCe-Ni/Cocatalystshowedthebestcatalyticactivityforthesteamreformingofallthefourmodelcompounds.Afterlong-termexperimentat700°CandtheS/Cratioof9,theCe-Ni/Cocatalyststillmaintainedexcellentstabilityforthesteamreformingofthesimulatedbio-oil(mixedbythefourcompoundswiththeequalmasses).WithCaOcalcinatedfromcalciumacetateasCO2sorbent,thecatalyticsteamreformingexperimentcombinedwithcontinuousinsituCO2adsorptionwasperformed.WiththecomparisonofthecasewithouttheaddingofCO2sorbent,thehydrogenconcentrationwasdramaticallyimprovedfrom74.8%to92.3%,withtheCO2concentrationobviouslydecreasedfrom19.90%to1.88%.
简介:这份报纸的目的是在设计下面并且离开设计条件改进最后阶段汽轮机和一台600MW蒸气汽轮机的exhaust兜帽的空气动力学的表演。在操作期间,在汽轮机和exhaust兜帽之间的强壮的流动相互作用在兜帽在流动行为上强加影响并且导致汽轮机的不能令人满意的空气动力学的表演并且用尽兜帽。exhaust兜帽因此有潜力以空气动力学的效率被改善。就在汽轮机和exhaust兜帽之间的流动相互作用而言,更弥漫的结束墙的侧面被优化。联合模型汽轮机和模型用尽兜帽计算和实验被执行验证优化的效果。模型实验证明设计修正导致了全面压力恢复系数的实质的增加。流动和空气动力学的表演照原尺寸最后一台阶段汽轮机并且照原尺寸用尽兜帽被模仿探索流动物理改变到更弥漫的几何学的修正。湿蒸气作为流动媒介被选择。在不同操作条件下面的实际流动地被分析。
简介:Forsyngasproduction,thecombustionoffossilfuelsproduceslargeamountsofCO2asagreenhousegasannuallywhichintensifiesglobalwarming.Inthisstudy,chemicalloopingcombustion(CLC)hasbeenutilizedfortheeliminationofCO2emissiontoatmosphereduringsimultaneoussyngasproductionwithdifferentH2/COratioinsteamreformingofmethane(SR)anddryreformingofmethane(DR)inaCLC-SR-DRconfiguration.InCLC-SR-DRwith184reformertubes(similartoanindustrialscalesteamreformerinZagrosPetrochemicalCompany,Assaluyeh,Iran),DRreactionoccursoverRh-basedcatalystsin31tubes.Also,SRreactionishappenedoverNi-basedcatalystsin153tubes.CLCviaemploymentofMn-basedoxygencarrierssuppliesheatforDRandSRreactionsandproducesCO2andH2Oasrawmaterialssimultaneously.AsteadystateheterogeneouscatalyticreactionmodelisappliedtoanalyzetheperformanceandapplicabilityoftheproposedCLC-SR-DRconfiguration.Simulationresultsshowthatcombustionefficiencyreached1attheoutletoffuelreactor(FR).Therefore,pureCO2andH2OcanberecycledtoDRandSRsides,respectively.Also,CH4conversionreached0.2803and0.7275attheoutletofSRandDRsides,respectively.Simulationresultsindicatethat,3223kmolh-1syngaswithaH2/COratioequalto9.826wasproducedinSRsideofCLC-SR-DR.Afterthat,1844kmolh-1syngaswithaH2/COratioequalto0.986wasachievedinDRsideofCLC-SR-DR.ResultsillustratethatbyincreasingthenumberofDRtubesto50tubesandconsidering184fixedtotaltubesinCLC-SR-DR,CH4conversionsinSRandDRsidesdecreased2.69%and3.31%,respectively.However,thissubjectcausedtotalsyngasproductioninSRandDRsides(inallof184tubes)enhanceto5427kmolh-1.Finally,thermalandmolarbehaviorsoftheproposedconfigurationdemonstratethatCLC-SR-DRisapplicableforsimultaneoussyngasproductionwithhighandlowH2/COratiosinanenvironmentalfriendlyprocess.