南水北调受水区某水厂炭砂滤池运行特性及生物安全性研究

Research on the operation characteristics and bio-safety of a carbon-sand filter in a water plant in the water receiving area of South-to-North Water Transfer Project

南水北调受水区某水厂采用活性炭和石英砂叠加结构的滤池,该炭砂滤池与传统生物活性炭池具有一定的差异性,对其运行特性及生物安全性做了解析。研究发现,高温高藻期采用臭氧和炭砂滤池组合工艺可减少滤池出水的致病菌和蓝藻,同时对有机物的去除也略有提高;滤池对氯化消毒副产物有一定的去除作用,但在夏季存在不稳定性,与活性炭中有机物的释放及炭料表面鞘氨醇单胞菌等菌属的季节性差异相关联;高温期滤池有军团菌和曲霉菌等致病菌泄露的风险,而冬季低温期生物安全性较高。因此,夏季对炭砂滤池的运行工况应进一步优化,冬季可适当延长反洗周期,以利于降解有机物的功能菌附着在炭料上。

A drinking water plant,located in the water receiving area of the South-to-North Water Transfer Project,is using a superimposed-structure filter with activated carbon and quartz sand,which has certain differences with the traditional biological activated carbon filter.The filter＇s operational characteristics and biosafety were analyzed.It was found that the combination of ozone and carbon-sand filter in the high-temperature and high-algae period could reduce the pathogenic bacteria and cyanobacteria in the filter effluent,and the removal of organic matters was also slightly improved.The carbon-sand filter had a certain removal of chlorination disinfection byproducts,but with instability in summer,which was associated with the release of organics from activated carbon and seasonal variations of sphingomonas.During the high-temperature period,there was risk of leakage of pathogens such as Legionella and Aspergillus,while biosafety is higher during the cold period in winter.Therefore,it suggests that the operating conditions of the carbon-sandfilter should be further optimized in the summer,and the backwash cycle can be prolonged in the winter to facilitate the attachment of the functional bacteria that degrade organic matter.