大气污染与控制工程考试复习整理VIP免费

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.（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:theplumerisingadistancehabovethetopofthestackbeforelevelingout.△（17）PrimaryParticles:Particlesfoundintheatmosphereintheforminwhichtheywereemitted,forexamples,NO,CO,SO2（18）PointSources:smallnumberoflar...