城市生活污水CASS工艺设计-沈洁龙

北京理工大学珠海学院2011届本科生毕业设计（论文）I城市生活污水CASS工艺设计摘要随着工农业生产的迅速发展和人民生活水平的不断提高,用水紧张和污水排放的问题已越来越突出.目前,我国城镇绝大部分的生活污水采用直接排放的方式,没有采取应有的治理措施,加重了对环境的污染.在国家可持续发展的新政策下,环境保护已受到各级政府和全国人民的重视,，环境污染日趋严重，加大城市生活污水治理力度势在必行。现拟建一座某城市生活污水处理厂，处理规模为60000m3/d，设计出水水质执行《污水综合排放标准(GB8978—1996)一级处理标准》。本设计采用周期循环曝气活性污泥法（CASS）工艺，此工艺有机物的去除率预计为90～95%，氮的去除率可以达到70～80%，磷的去除率可达90%。CASS工艺技术成熟，流程简单、管理方便、运行方式灵活、处理效率高、具有良好的脱氮除磷效果、出水水质好，该工艺已经成功运用于工程实践，具有十分良好的经济效益、环境效益和社会效益。本设计包含污水处理工艺流程的确定，工艺流程中各单体的计算，施工图纸的绘制等。关键字：污水处理厂CASS工艺脱氮除磷去除率北京理工大学珠海学院2011届本科生毕业设计（论文）IICASSProcessDesignOfMunicipalSewageABSTRACTWiththerapiddevelopmentofindustrialandagriculturalproductionandimprovelivingstandards,waterstressandsewagedisposalproblemshavebecomeincreasinglyprominent.Atpresent,mostcitiesandtownsdirectdischargeofsewagebytheway,didnottakepropercontrolmeasures,addingtothepollutionoftheenvironment.inthecountryunderthenewpolicyofsustainabledevelopment,environmentalprotectionhasbeenthepeopleofalllevelsofgovernmentandthenationalattention,environmentalpollutionismoreserious.Soitisbothinevitableandnecessarytodeveloptheurbansewagetreatment.Now,aSewagetreatmentplantwillbeplanedtobuildinXXXcity.TreatmentscaleofSewageis60000m3/d.Theeffluentqualitycarriesoutprimarystandardsfromintegratedwastewaterdischargestandard—GB8978—1996.Thisdesignusescyclicactivatedsludgesystem(CASS).Theestimatedremovalefficiencyoforganicmaterialsisbetween90percentand95percent,theremovalefficiencyofnitrogenrangesfrom70to80percent.,andremovalefficiencyofphosphoruscanreach90%.TheCASSprocessisaripetechnologywithalotofadvantages,suchasbeingeasytomanage,flexibleoperationalways,gooddisposedeffect,andgoodnitrogenremovaleffect.Itissuitableforsmallandmid-scalemunicipalwastewatertreatmentplantsbecauseofitslowinvestmentandoperationalcost.Theprocessinghasbeensuccessfullyappliedforactualengineeringpractice,andhasgoodeconomic,environmentalandsocialefficiency.Thisdesigncontainstheidentification,eachmonomerprocessofcalculation,constructiondrawingsdrawingetc.Keywords:sewagetreatmentplant,CASStechnique,Nitrogenandphosphorusremoval；removalefficiency.北京理工大学珠海学院2011届本科生毕业设计（论文）III目录摘要............................................................................................................IABSTRACT.................................................................................................II第一章绪论..............................................................................................11.1我国城市污水处理概况................................................................................11.2城市污水来源................................................................................................11.3设计的意义及指导思想................................................................................11.3.1设计的意义.................................................................................................11.3.2指导思想.....................................................................................................21.4国内外发展概况............................................................................................21.4.1AB法............................................................................................................21.4.2A2/O生物脱氮除磷工艺.............................................................................21.4.3氧化沟工艺.................................................................................................31.4.4SBR工艺.....................................................................................................31.4.5CASS工艺...................................................................................................31.5设计依据及原则............................................................................................31.5.1设计依据.....................................................................................................31.5.2设计原则.....................................................................................................31.6工程概况........................................................................................................41.6.1基础资料.....................................................................................................41.6.2水质指标.....................................................................................................4第二章污水处理厂工艺方案..................................................................5北京理工大学珠海学院2011届本科生毕业设计（论文）IV2.1设计方案论证................................................................................................52.2原污水可生化性分析....................................................................................52.3工艺选择及方案比选....................................................................................62.3.1A2/O工艺.....................................................................................................62.3.2氧化沟工艺及其变形..................................................................................72.3.3CASS工艺...................................................................................................92.3.4确定工艺方案...................................