给排水专业英语Unit7.ppt

给排水专业英语Unit7.ppt

《给排水专业英语Unit7.ppt》由会员分享，可在线阅读，更多相关《给排水专业英语Unit7.ppt（14页珍藏版）》请在冰点文库上搜索。

SpecializedEnglishforWaterandWastewaterEngineering,给排水专业英语,主讲教师：

李康,Lesson7Chemicaloxidation,化学氧化,7.1WordsandexpressionsReview,Frictionalresistance摩擦阻力反冲洗BackwashingInterception,intsepnn.拦截，截留Electrokinetici,lektrkainetikadj.动电学的，电动的Terminatet:

mineitv.终止，停止，结束Hydraulicshaidr:

liksn.水力学快滤池RapidfilterGravityfilter重力滤池,7.1WordsandexpressionsReview,Filtermedium过滤介质，滤料无烟煤Anthracite煤-砂滤床Coal-sandbedsDualmediafilter双层滤料滤池Coarsemedia粗滤料Turbiditybreakthrough浊度穿透Filtercycle过滤周期Filtereffluent滤后水，滤池出水Filterinfluent滤前水，滤池进水,5,7.2NewwordsandexpressionsDisinfectionChlorineInfluentflowOzoneOxidationReductionEnzymeCatalystSulfideBenzene,消毒,氯,入流,臭氧,氧化,酶,催化剂,硫化物,苯,还原,6,7.2NewwordsandexpressionsOxidant/Oxidizingagent氧化剂Reducer/Reducingagent还原剂Oxidationpotential氧化电势，氧化性Reductionpotential还原电势，还原性Advancedoxidationprocess高级氧化工艺（AOP）Hydrogenperoxide过氧化氢Ammonia氨Nonbiodegradable不能生物降解的Oxidation-reductionreaction氧化还原反应,7.3Importantsentences,（第一段）Includedinthefollowingdiscussionisanintroductionofthefundamentalconceptsinvolvedinchemicaloxidation,anoverviewoftheusesofchemicaloxidationinwastewatertreatment,andadiscussionoftheuseofchemicaloxidationforthereductionofBODandCOD,theoxidationofammonia,andoxidationofnonbiodegradableorganiccompounds.nonbiodegradableorganiccompounds难降解有机物有哪些？

oxidationandreduction（第二段）Thepurposeofthefollowingdiscussionistointroducethebasicconceptsinvolvedinchemicaloxidationreactions.Thetopicstobediscussedinclude

（1）oxidation-reductionreactions,

（2）halfreactionpotentials,（3）reactionpotentials,（4）equilibriumconstantsforredoxequationsforredoxequations,and（5）rateofoxidation-reductionreactions.redox氧化还原作用？

基本概念,氨,概述,平衡常数,7.3Importantsentences,1.（第三段）Oxidation-reductionreactions（5min）copper-Cuzinc-ZnOxidation-reductionreactionsOxidationhalfreaction？

Reductionhalfreaction？

equation-two-electronchange,7.3Importantsentences,（第四段）Half-reactionpotentialsBecauseofthealmostinfinitenumberofpossiblereactions,therearenosummarytablesofequilibriumconstantsforoxidation-reductionreactions.Ofthemanypropertiesthatcanbeusedtocharacterizeoxidation-reductionreactions,theelectricalpotential（i.e,voltage）oremfofthehalfreactionisusedmostcommonly.Thus,everyhalfreactioninvolvinganoxidationorreductionhasastandardpotentialE0associatedwithit.（11-4）和（11-5）公式是否有错误？

Thehalfreactionpotentialisameasureofthetendencyofareactiontoproceedtotheright.Halfreactionwithlargepositivepotential,E0,tendtoproceedtotherightaswritten.Converselyhalfreactionswithlargenegativepotential,E0,tendtoproceedtotheleft.Therelationshipbetweenelectricalpotentialandreaction?

无穷的，无限的,electromotiveforce,7.3Importantsentences,（第五段）ReactionpotentialsThehalf-reactionpotentials,discussedabove,canbeusedtopredictwhetherareactioncomprisedoftwohalfreactionswillproceedaswritten.ThetendencyofareactiontoproceedisobtainedbydeterminingtheE0reactionfortheentirereactionasgivenbythefollowingexpression.ThepositivevaluefortheE0istakenasanindicationthatthereactionwillproceedaswritten.Themagnitudeofthevalue,aswillbeillustratedsubsequently,canbetakenasameasureoftheextenttowhichthereactionaswrittenwillproceed.,减轻，缓和,7.3Importantsentences,（第六段）Rateofoxidation-reductionreactions.Asnotedpreviously,thehalf-reactionpotentialscanbeusedtopredictwhetherareactionwillproceedaswritten.Unfortunately,thereactionpotentialprovidesnoinformationabouttherateatwhichthereactionwillproceed.Chemicaloxidationreactionsoftenrequirethepresenceofoneormorecatalystsforthereactiontoproceedortoincreasetherateofreaction.Transitionmetalcations,enzymes,pHadjustment,andavarietyofproprietarysubstanceshavebeenusedascatalysts.,Transitionmetal过渡金属？

enzyme酶胃蛋白酶、胰酶、淀粉酶、消化酶,7.3Importantsentences,（第七段）ApplicationsInthepast,chemicaloxidationwasusedmostcommonlyto

（1）reducetheconcentrationofresidualorganics,

（2）controlodors,（3）removeammonia,and（4）reducethebacterialandviralcontentofwastewater.Chemicaloxidationisespeciallyeffectivefortheeliminationofodorouscompounds（e.g.,oxidationofsulfidesandmercaptans）.Nowchemicaloxidationiscommonlyusedto

（1）improvethetreatabilityofnonbiodegradable（refractory）organiccompounds,

（2）eliminatetheinhibitoryeffectsofcertainorganicandinorganiccompoundstomicrobialgrowth,and（3）reduceoreliminatethetoxicityofcertainorganicandinorganiccompoundstomicrobialgrowthandaquaticflora.ThechemicaloxidationofBODandCOD,ammonia,andrefractoryorganiccompoundsisconsideredinthissection.,硫醇,毒性,水生植物,7.3Importantsentences,（第九段）Chemicaloxidationofnonbiodegradableorganiccompounds.Thedosagesincreasewiththedegreeoftreatment,whichisreasonablewhenitisconsideredthattheorganiccompoundsthatremainafterbiologicaltreatmentaretypicallycomposedoflow-molecular-weightpolarorganiccompoundsandcomplexorganiccompoundsbuiltaroundthebenzeneringstructure.Pilot-plantstudiesmustbeconductedwheneitherchlorine,chlorinedioxide,orozoneistobeusedfortheoxidationofrefractoryorganicstoassessboththeefficacyandrequireddosages.,7.3Importantsentences,（第十一段）Thebreakpointchlorinationprocesscanbeusedfortheremovalofammonianitrogenfromtreatment-planteffluents,eitheraloneorincombinationwithotherprocesses.Toavoidthelargechlorinedosagesrequiredwhenusedalone,break-pointchlorinationcanbeusedfollowingbiologicalnitrificationtoachievelowlevelsofammoniaintheeffluent.Tooptimizetheperformanceofthisprocessandtominimizeequipmentandfacilitycosts,flowequalizationisusuallyrequired.Also,becauseofthepotentialtoxicityproblemsthatmatdevelopifchlorinatedcompoundsaredischargedtotheenvironment,itisusuallynecessarytodechlorinatetheeffluent.breakpointchlorination折点氯化？