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1、1EnvironmentalscienceandengineeringAmosThomasDemonTEAM:4082021/7/25Thesearetheidealenvironmentthatwedreamtolivein.2021/7/25Wakeup!Thesearetheenvironmentweliveinnow!2021/7/25pollutionsWaterpollutionWaterpollutionisthecontaminationofwaterbodiessuchaslakes,rivers,oceans,andgroundwater.Waterpolluti
2、onTheheavysmokepipedfromthefactorychimneys.AirpullutionAutomobileexhaustThenoisepollutionTherubbishweproducedTheWhitepollutionInmywordsTheenvironmentistheworldwelivein,andthenaturalsurroundings.Everytimewespreadourcitys,everygarbageweproduce,everydropofwaterwepollute,wehurtour“mothernature”.Werel
3、yontheEarthforeverythingweneedtosurvive,solet’stakecareofit.Wecan’tlivewithoutwater,butnowthewaterwaspolluted.Itisthebiggestproblem.Itinfluencesourdailylife.Soweshouldfindawaytosolvethisproblem.14WaterTreatmentProcesses15WaterTreatment16Watertreatmentoperationsfulfilloneorthreekeytasks:removalofp
4、articulatesubstancessuchassandandclay,organicmatter,bacteria,andalgae;removalofdissolvedsubstancessuchasthosecausingcolorandhardness;andremovalordestructionofpathogenicbacteriaandviruses.Theactualselectionoftreatmentprocessesdependsonthetypeofwatersourceandthedesiredwaterquality.水处理操作完成一个或三个关键任务:
5、去除颗粒物如沙粒和粘土、有机物、细菌和藻类,去除溶解物质如那些产生颜色和硬度的,及除去或消灭致病细菌和病毒。处理工艺的实际选择依赖于水源的类型和水质要求。17Screeningtoremovelargesolidssuchaslogs,branches,rags,andsmallfishisthefirststageinthetreatmentofwater.Allowingsuchdebrisintothetreatmentplantcoulddamagepumpsandclogpipesandchannels.Forthesamereasons,waterintakesareloca
6、tedbelowthesurfaceofthelakeorriverinordertoexcludefloatingobjectsandminimizephysicaldamagefromice.格栅是水处理的第一阶段,它能去除大块固体例如木头、树枝、破布和小鱼。这些垃圾进入处理厂会损害水泵并堵塞管道。同理,入水口设置在湖泊或者河流表面以下,以排除漂浮物并最小化冰块的物理破坏。18SedimentationSedimentation,theoldestandmostwidelyusedformofwaterandwastewatertreatment,usesgravitysettlin
7、gtoremoveparticlesfromwater.Itisrelativelysimpleandinexpensiveandcanbeimplementedinbasinsthatareround,square,orrectangular.Asnotedearlier,sedimentationmayfollowcoagulationandflocculation(forhighlyturbidwater)orbeomitte