摘要
【目的】进行炭砂滤池水反冲洗参数优化设计,减少水耗,保证冲洗效果,可为水厂炭砂滤池实际运行提供技术参考。【方法】以南京市某水厂沉后水为原水进行炭砂滤池中试研究,考察水反冲洗参数对滤料混层和滤后水浑浊度的影响,探究最佳水反冲洗参数组合下炭砂滤池运行效果和细菌群落结构。【结果】水反冲洗强度为12~15 L/(m^(2)·s)能够较好地实现炭砂滤池分层效果;水反冲洗强度为9 L/(m^(2)·s),历时7 min,分层冲洗强度为12 L/(m^(2)·s),历时5 min,即可以保证滤池冲洗干净,滤后水浑浊度小于0.7 NTU。运行期间炭砂滤池对浑浊度的平均去除率为95.8%,对高锰酸盐指数的平均去除率为11.1%,对氨的平均去除率为45.9%,出水硝酸盐出现累积现象,但整体出水水质满足我国《生活饮用水卫生标准》(GB 5749—2022)。细菌16S rRNA基因高通量测序分析表明,炭砂滤池优势菌群主要为变形菌门(Proteobacteria)、酸菌杆门(Acidobacteriota)和绿弯菌门(Chloroflexi),相对丰度占比超过65%。【结论】采用小水冲和分层冲洗的反冲洗方式,可以改善炭砂滤料混层现象,降低水耗,并保证炭砂滤池的运行效果。
[Objective]Conduct optimization design of water backwash parameters for the activated carbon-sand filter to reduce water consumption and ensure backwashing effectiveness,which can provide technical reference for the actual operation of the activated carbon-sand filter in the water plant.[Methods]A pilot test of an activated carbon-sand filter was conducted using sedimented water as the feedwater from a water treatment plant(WTP)in Nanjing.The impact of various water backwash parameters on the layering within the filter and the turbidity of filtered water was investigated,and the performance and bacterial community structure of the activated carbon-sand filter under the optimal combination of water backwash parameters were thoroughly examined.[Results]The findings of this study indicated that a water backwash intensity ranging from 12 L/(m^(2)·s)to 15 L/(m^(2)·s)led to optimal layering within the activated carbon-sand filter.Additionally,the combination of 7 minutes of backwash at an intensity of 9 L/(m^(2)·s)followed by 5 minutes of layering backwash at 12 L/(m^(2)·s)proved to be effective in ensuring thorough cleaning of the filter and reducing the turbidity of the filtered water to less than 0.7 NTU.Throughout the operational period,notable removal efficiencies were observed,with a 95.8%reduction in turbidity,an 11.1%decrease in permanganate index,and a 45.9%reduction in ammonia nitrogen.Notably,nitrate levels increased in effluent.Moreover,the effluent quality of the activated carbon-sand filter could meet our country′s Standards for Drinking Water Quality(GB 5749—2022).Furthermore,the bacterial 16S rRNA gene high-throughput sequencing results revealed that the dominant bacterial communities within the activated carbon-sand filter primarily consisted of Proteobacteria,Acidobacteriota,and Chloroflexi,which accounted for over 65%of the total bacteria.[Conclusion]Small water backwashing and layering backwashing techniques can guarantee the activated carbon-sand filter′s operational efficacy,minimize water consumption,and improve the phenomena of mixed layers in filter media.
作者
鲍寻
袁聪
祖振权
张家萱
秦庆东
BAO Xun;YUAN Cong;ZU Zhenquan;ZHANG Jiaxuan;QIN Qingdong(Nanjing Water Group Co.,Ltd.,Nanjing 210018,China;School of Civil Engineering,Southeast University,Nanjing 211189,China)
出处
《净水技术》
2025年第1期74-80,108,共8页
Water Purification Technology
基金
南京水务集团有限公司科技创新项目(YF2022-011)。
关键词
炭砂滤池
反冲洗
滤后水
浑浊度
参数优化
activated carbon-sand filter
backwash
filtered water
turbidity
parameter optimization
