过滤工艺中颤蚓的迁移分布规律

第32卷第5期土木建筑与环境工程Vol.32No.52010年10月JournalofCivil,Architectural&EnvironmentalEngineeringOct.2010过滤工艺中颤蚓的迁移分布规律聂小保1,2,黄廷林1,张金松3,张爽1,李伟1,李晓钰1(1.西安建筑科技大学环境与市政工程学院,西安710055;2.长沙理工大学水利学院,长沙410076;3.深圳水务集团,广东深圳518031)收稿日期:2010�03�07基金项目:国家重大科技专项课题(2009ZX07423�003);教育部创新团队支持项目(IRT0853)作者简介:聂小保(1979�),男,博士生,主要从事水质微污染控制与水资源保护方面的研究,(E�mail)niexb1871@sina.com。摘�要:中试条件下研究了颤蚓在过滤工艺中的迁移分布规律,并考察了滤速和过滤周期对颤蚓迁移分布的影响,以及反冲洗后滤池中颤蚓的分布情况。结果表明:颤蚓在滤池中沿滤床深度方向的迁移与颤蚓体长和滤料粒径有关,颤蚓体长越小、滤料粒径越大,则迁移幅度越大;滤速是颤蚓迁移的主要动力,滤速的提高会引起下层滤床中颤蚓数量的增加,颤蚓泄露风险加大;过滤周期的延长将促进颤蚓的迁移,适当缩短过滤周期有利于水厂颤蚓泄露风险控制;反冲洗可以实现颤蚓从净水工艺中的彻底去除,反冲洗强度越大,颤蚓的去除效果越好。为有效控制颤蚓泄露风险,滤池滤速和过滤周期宜分别控制在9.4m/h和12h以下,反冲洗强度则控制在25L/s�m2左右,此时颤蚓去除率为97.7%。关键词:颤蚓;滤池;迁移;分布中图分类号:TU991.25;X174��文献标志码:A��文章编号:1674�4764(2010)05�0088�05MigrationandDistributionRulesofTubifexinFiltrationNIEXiao�bao1,2,HUANGTing�lin1,ZHANGJin�song3,ZhangShuang1,LIWei1,LIXiao�yu1(1.SchoolofEnvironmentalandMunicipalEngineering,XianUniversityofArchitecture&Technology,Xian710055,P.R.China;2.SchoolofWaterConservancy,ChangshaUniversityofScience&Technology,Changsha410076,P.R.China;3.ShenzhenWater(Group)Co.,Ltd.,Shenzhen518031,Guangdong,P.R.China)Abstract:Therulesofmigrationanddistributionregulationoftubifexinfiltrationwerestudiedinthepilotsystem.Meanwhile,theinfluencesoffiltrationrate,filtrationcycleandbackwashingonthewormsmigrationanddistributioninfiltraionwerediscussed.Theresultsshowedthatboththewormslengthandtheparticlesizeoffiltermediahadobviouseffectsonmigrationanddistribution:thesmallerthewormslengthandthelargertheparticlesizeoffiltermediawere,thestrongerthewormsmigrationcapacitywas.Thefiltrationratewasthemainmigrationpoweroftubifexinfiltration,whichmeanthighfiltrationratecouldresultinthewormsleakagerisk.Prolongingfiltrationcyclepromotedmigration,thusitisbeneficialtocontroltubifexleakageriskthatshorteningfiltrationcycle.Theremoveoftubifexinarealsensecanberealizedbybackwashing.Andthestrongerthebackwashingintensityis,thebettertheremovalefficiencyis.Basedontheexperimentalresults,tocontrolthewo