基于非曝气区关键点流速的污水厂运行状况分析

书基于非曝气区关键点流速的污水厂运行状况分析杨亚红1，彭党聪2，郑阳光2(1．兰州理工大学土木工程学院，甘肃兰州730050;2．西安建筑科技大学环境与市政工程学院，陕西西安710055)摘要:流速是水处理工艺的关键运行参数之一，基于测定活性污泥处理构筑物单元的关键点流速，对试运行的新建污水厂运行状况进行后评价。结果表明:①4#厌氧池池底流速最高达0．16m/s，而池顶流速低至0．059m/s，确保了污泥混合效果、降低了搅拌功率、确保了厌氧环境;而5#厌氧池内断面大部分流速远小于活性污泥悬浮所需最小流速(0．15m/s)，可能存在污泥沉淀。②缺氧池内混合液回流量过大，造成缺氧池内硝酸盐氮浓度过高，能量浪费，消耗进水中有限的碳源，造成对总氮的去除率降低。③缺氧池出水廊道中的水流速度为0．20～0．26m/s，设计合理。④混合液回流廊道宽为2000mm，而缺氧区出水廊道宽为1500mm，这是造成混合液回流廊道的流速远小于出水廊道流速和污泥悬浮所需最小流速的主要原因。关键词:污水厂;运行状况;流速;非曝气区关键点;活性污泥法中图分类号:X703文献标识码:C文章编号:1000－4602(2015)03－0112－04基金项目:国家水体污染控制与治理科技重大专项(2009ZX07317－009)AnalysisonOperatingConditionofWWTPbyMeasuringFlowVelocityatKeyPointsinNon-aerationZoneYANGYa-hong1，PENGDang-cong2，ZHENGYang-guang2(1．CollegeofCivilEngineering，LanzhouUniversityofTechnology，Lanzhou730050，China;2．SchoolofEnvironmentalandMunicipalEngineering，Xi’anUniversityofArchitectureandTechnology，Xi’an710055，China)Abstract:Flowvelocityisoneofthekeyoperationparametersofwastewatertreatmentprocesses．ThecommissioningconditionofanewWWTPwaspost-evaluatedbymeasuringflowvelocityatthekeypointsintheactivatedsludgetreatmentunit．Theresultsshowedthat:①Themaximumvelocityvaluewas0．16m/sinthebottomofthe4#anaerobictankandtheminimumvelocityvaluewas0．059m/sinthetop，whichensuredthemixingeffectofsludge，reducedthestirringpowerandachievedtheanaerobicenvironment．However，mostofcross-sectionvelocityinthe5#anaerobictankwasfarlessthanthemini-mumflowvelocity(0．15m/s)requiredforactivatedsludgesuspension，whichmeantthatsludgesedi-mentationmighttakeplace;②Themixedliquorthatreturnedintotheanoxictankwastoolarge，causingtoohighconcentrationofnitrate，energywaste，consumptionoflimitedcarbonsourceandlowremovalrateofTN;③Theflowvelocityintheeffluentcorridoroftheanoxictankwas0．20to0．26m/s，show-ingthereasonabledesign;④Thewidthofthecorridorforthereturnedmixedliquorwas2000mmandthewidthoftheeffluentcorridorforanoxiczonewas1500mm，whichwasthemainreasonforthefact·211·第31卷第3期2015年2月中国给水排水CHINAWATEＲ＆WASTEWATEＲVol．31No．3Feb．2015thattheflowvelocityinthecorridorofthereturnedmixe