氢能源--化学

Hydrogen,theidealnewenergyforthefuture,化实0901200912028饶凌萍,Hydrogen-theidealnewenergyforthefuture,Thecurrentenergycrisis,Naturalgasreservesareabout131,800152,900trillioncubicmeters.Itsannualextractionvolumeismaintainedat2300trillioncubicmeterssoitwillbedepletedwithin50years,Thereareabout560billiontonsofcoalreserves.Theamountofcoalminingin1995was33milliontons,inthatway,coalsupplycanmeetto160years.,Uraniumcurrentannualextractionvolumeis60,000tonnesandaccordingtotheestimationoftheWorldEnergyCouncilin1993,theuraniumsupplycanbemaintaineduntilthemid-2030s.Fusioncannotbeachievedevenby2050.,Estimatesofoilreserves,accordingtoacomprehensive,thedisposaloffossilenergylimitisabout1180151billiontonsandtheoilreservesmaybedepletedin2050declared.,。,Hydrogen-theidealnewenergyforthefuture,Whatcanwedo?,HydrogenWhenconventionalenergycrisisandnewsecondaryenergydevelopmenthappenatthesametime,peoplelookforwardtothehydrogenasnewsecondaryenergy.Theexpertsathomeandabroadpredict:hydrogenenergywillbecomethemostpromisingfossilfueloneofalternativeenergy.,Hydrogen-theidealnewenergyforthefuture,Thehydrogenadvantage:,Thepreparingrawmaterialofhydrogencanbewaterontheearth,thestoreofwaterresourcesisabundant,andinthelongtermisnotrestricted.,Lesspollution.Wateristheproductofhydrogenafterburning,theenvironmentalpollutionislesser,andwontdestroythenaturalcycleofwater.,Hydrogenburningspeedishigh,hasbigcalorificvalue(H(298.15K)=286kJ/mol).Accordingtothis,hydrogencanserveasagooddynamicenergy.Experimentsshowthathydrogencombustionefficiencymorethan45%higherthangasoline.,Thehydrogencanbestored,andelectricityisdifficulttostorage.,Thehydrogenapplicationscopeisbroad,theadaptabilityisstrong,forexamplethroughhydrogenreductionwaycanbedirectlyusedtosmeltsteelandpreparemethane.,Hydrogen-theidealnewenergyforthefuture,Inadditiontothenuclearfuel,hydrogencalorificvalueisthehighestamongallthefossilfuel,chemicalfuelandbiofuels,heatofcombustionofhydrogenisthreetimesthatofgasoline.,Hydrogen-theidealnewenergyforthefuture,Hydrogenproductionmethods:,Modificationofthelegalsystemofhydrogenfromfossilfuels,Mainlyusingoil,coalandnaturalgasasrawmaterial,withnickelmetalcompoundsascatalyst,makehydrocarbongasesandwatervaporrole,generatehydrogenandcarbondioxidegasmixture.,CxHy+H2O,Hightemperatureandpressure,catalyze,H2+CO2,Inaddition,watergasandsynthesisgasobtainedafterthecoalgasification,isalsocommonlyusedmethodtomakehydrogen.,Coal,CO+H2,CO+H2O,C2O+H2,Hydrogen-theidealnewenergyforthefuture,Cokeovengasvariablepressureadsorptionhydrogenplant,Future-orientedenergyplant,Hydrogen-theidealnewenergyforthefuture,Hydrolysistohydrogen,1.Electrolysisofwater:Itisthroughtheuseofelectricitytosplitwaterintohydrogenandoxygen.H2O+eH2+1/2O2,Schematicdiagramoftheelectrolysisofwater:,2.Alkalineelectrolysis:AlkalineelectrolysispoolistousecorrosiveKOH(potassiumhydroxide)aselectrolytesolution.,3.Polymerelectrolytefilmelectrolysis:Dontneedliquidelectrolyte,whichgreatlysimplifiedthedesignprocess.Theelectrolyteisacidpolymerfilm.,Hydrogen-theidealnewenergyforthefuture,4.hightemperatureelectrolyticHigh-temperatureelectrolysismethodisbasedonhigh-temperaturefuelcelltechnology.Akindoftypicaltechnologyissolidoxideelectrolysiscellmethod.Thismethodisbasedonthesolidoxidefuelcells,usuallyinthe700-1000operation.Insuchtemperature,theelectrodereactionismorereversible,andfuelcellreactionscanbemoreeasilyintoelectrolyticaction.,5.PhotoelectrolysisPhotoelectricsystemwithelectrolyticmaydevelopcommercialuse.Thistypeofsystemisveryflexible,canthroughphotoelectrolysistoproduceelectricpowertestorthroughelectrolysispoolproducehydrogen.,6.biologicalphotolysisBiologicalphotolysisofhydrogenproductionbasedontwobiologicalsteps:photosynthesisandtheuseofhydrogenasesuchasgreenalgaeandblue-greenalgaetocatalytichydrogen.Photosynthesis：2H2O4H+4e+O2Hydrogenproduction：4H+4e2H2,7.HightemperaturedecompositionPyrolysistemperatureofthewaterrequiredisabout3000.Atthispoint,10%ofthewaterisdecomposition,withtheremaining90%canberecycled.,8.thermo-chemicalhydrolysisItmeansthroughaseriesofThermo-chemicalreactiontosplitwaterintohydrogenandoxygenprocess.,Hydrogen-theidealnewenergyforthefuture,Photolysisofwatertohydrogensystem,Hydrolysishydrogenproductionequipment,Hydrogen-theidealnewenergyforthefuture,Hydrogenstorageandtransportation,（1）Hydrogenstorage,1.Highpressuregasstorageisthemostcommonhydrogenstoragemethod,asthehydrogendensity,inthecaseofhighpresscanitbestoredinaspecialhighpressurecylinders,usuallymorethan1.5MPapressure,hydrogengascanbedischargedthroughthevalvecontrolandadjustthesizeofdisplacement.,2.Lowtemperatureliquidhydrogenstorage(alsocalledcryogenicliquidhydrogenstorage)meansinthestandardatmosphericpressure,hydrogensystemwillbefrozenat-252.72,makeitintoaliquidstoredinspecialcryogenicdewar(highvacuuminsulatedcontainers).,3.Metalhydridehydrogenstorageisaanewtypemethodputforwardtosolvetheproblemofhydrogenstorage.,4.Thereareothermethodstostorehydrogenlikeorganiccompoundshydrogenstorage,carbonnanotubehydrogenstorage,hydrogenstorageofcarbongel,glassmicrospheresforhydrogenstorage,hydrogenstorageandotherhydrideligand,Hydrogen-theidealnewenergyforthefuture,Therearefourmainstoragestateofthetransportationofhydrogen:lowvoltagehydrogen,highpressurehydrogen,liquidhydrogenandsolidhydrogen(metalhydridehydrogenstorageandorganichydridehydrogenstorage,etc.).Transportationtechnologymainlypipelinetransport,motorvehicletransportation,shipping.Choosewhichtransportationmodebasedonthefollowingfourcomprehensiveconsideration:Theenergyefficiencyofthetransportprocess,hydrogentrafficvolume,transportprocessofhydrogentransportloss,mileage.,(1)thetransportofhydrogen,液氢公路运输车,液氢铁路运输车,Hydrogen-theidealnewenergyforthefuture,Hydrogenapplication,Hydrogenasaclean,efficient,safeandsustainablenewenergy,mainlyusedinthefollowingthreeways:,1,theuseofhydrogenandtheoxidantreacttoreleaseheat,suchasfuelburninginheatenginetoproducethermalmechanicalwork;,2,theuseofhydrogenandtheoxidantinthecatalysttogetenergy,suchasthroughfuelcellsproduceelectricitydirectlyinthechemicalreaction;,3,theuseofthermonuclearreactionofhydrogenreleaseofnuclearenergy,suchasthehydrogenbombistousethethermonuclearreactionofhydrogenreleaseofnuclearenergy,hydr