第1页共10页编号:时间:2021年x月x日书山有路勤为径,学海无涯苦作舟页码:第1页共10页大气复习资料一、概念解释(1)Globewarming:GlobalwarmingistheincreaseintheaveragemeasuredtemperatureoftheEarth'snear-surfaceairandoceanssincethemid-twentiethcentury,anditsprojectedcontinuation.(2)VOCs:Volatileorganiccompoundsarethoseorganicliquidsorsolidswhoseroomtemperaturevaporpressurearegreaterthanabout0.01psia(=0.0007atm)andwhoseatmosphericboilingpointsareuptoabout500℉,whichmeansmostorganiccompoundswithlessthan12carbonatoms.(3)Wetscrubber:Adevicethatcollectsparticlesbycontactingthedirtygasstreamwithliquiddrops.ORAdeviceremovesparticulatesfromagassteambybringingtheparticlesintocontactwithaliquid.Theparticlesattachtotheliquidandcanberemovedinaslurrysolution.(4)Temperatureinversions:Itisaphenomenonthatthetemperatureincreaseswiththeheightincreasing.Thatstabilityalsolessenstheexchangeofwindenergybetweentheairlayernearthegroundandhighaltitudewinds.ORAtemperatureinversionsisathinlayeroftheatmospherewherethedecreaseintemperaturewithheightismuchlessthannormal.(5)ESP:Electrostaticprecipitator,whichislikeagravitysetterorcentrifugalseparator,butelectrostaticforcedrivestheparticlestothewall.Anditiseffectiveonsmallparticlesbelowabout5mindiameter.μ(6)SNCR:shortof“selectivenon-catalystreduction”.Itistheprocessthatinvolvesinjectingeitherammoniaorureaintothefireboxoftheboileratalocationwherethefluegasis760-1100(1,400and2,000°F)toreactwiththenitrogenoxides.Theresultingproductofthe℃chemicalredoxreactioniselementalnitrogen(N2),carbondioxide(CO2),andwater(H2O).(7)SCR:shortof“selectivecatalystreduction”.Itisameansofconvertingnitrogenoxides(NOx),alsoreferredtoasNOxwiththeaidofacatalystintodiatomicnitrogen(N2)andwater(H2O),undertheconditionof320-400℃(600-750℉)6NO+4NH3→5N2+6H2O,4NO+4NH3+O2→4N2+6H2O,2NO2+4NH3→3N2+6H2O.第2页共10页第1页共10页编号:时间:2021年x月x日书山有路勤为径,学海无涯苦作舟页码:第2页共10页(8)ThermalNO:ThermalNOxreferstoNOxformedbythesimpleheatingofoxygenandnitrogen,eitherinaflameorbysomeotherexternalheating,e.g.,alightingbot.(9)PM2.5:Particlewiththeaerodynamicdiameterlessthan2.5um,whichisalsocalledRespirableParticles.(10)Alternativefuel:Severalotherfuelsexceptofconventionalgasolineanddiesel,whichhavebeenusedformanyyearsinslighutlymodifiedautomobileengines,forreasonsofcostandavailability.(11)A/Fratio:Airtofuelratioforautoengines.ForanyhydrocarbonfuelwithformularCxHy,sonstoichoxygen=x+y/4.Forcompletecombustionofthisfuel,theequationisCxHy+(x+y/4)O2→xCO2+y/2O2,so(A/F)=(12)Leanbum:Leanburnreferstotheuseofleanmixturesinaninternalcombustionengine.Theair-fuelcanbeashighas65:1,sothemixturehasconsiderablylessfuelincomparisontothestoichiometriccombustionratio(14.7:1forpetrol,forexample).(13)Photochemicalsmog:Itisthechemicalreactionofsunlight,nitrogenoxidesandvolatileorganiccompoundsintheatmosphere,whichleavesairborneparticlesandground-levelozone.Photochemicalsmogisalightblueanditisthesecondarypollutantsintheatmosphere.(14)Aerodynamicdiameter:Airborneparticleshaveirregularshapes,andtheiraerodynamicbehaviorisexpressedintermsofthediameterofanidealizedsphericalparticleknownasAerodynamicdiameter.(15)HEPA:HighEfficiencyParticulateAir.Itisatypeofairfilterthatusedforremovingsolidparticlesfromgassteamsthatcontainfewofthem.(16)Plumerise:theplumerisingadistancehabovet...