O3-BAC对微污染水源水氨氮去除研究

针对福州市某水厂原传统处理工艺不能有效去除微污染水源水氨氮,出厂水氨氮不能稳定达标的情况,采用臭氧-生物活性炭(O3-BAC)处理工艺对水厂进行了中试研究,研究了臭氧投加量、水温、臭氧接触室气水比、活性炭滤池空床停留时间(EBCT)、流向等因素对氨氮去除的影响.结果表明:对于氨氮浓度为0.6~2.0 mg·L-1的微污染水源水质,最佳的臭氧投加量为2 mg·L-1;且当水温为16~24℃,臭氧接触室气水比为5∶3∶2,EBCT为15 min时,氨氮的去除效果在75%以上;此外,与下向流工艺相比,上向流工艺具有较高的去除率.

A study on removing ammonia nitrogen from micro-polluted source water using O3-BAC

The traditional treatment process in some of Fuzhou water plants is found to be not effective for removing ammonia nitrogen (NH4-N) and the stability control of effluent NH4-N. Therefore, a pilot scale study on treatment of ammonia nitrogen for water plant in this study was conducted through ozone-biological activated carbon (O3-BAC) process. Operational parameters such as the water O3 dosage, water temperature, ratio of gas to water in ozone contact chamber, empty bed contact time (EBCT) of activated carbon filter and directions of water flow on removal efficiency of NH4-N were investigated. The results showed that the optimum ozone dosage was 2 mg/L for raw water at NH4-N concentration of 0.6 mg/L to 2 mg/L. With the water temperature between 16~24 oC, ratio of the gas to water at 5:3:2 and EBCT for 5 min, the NH4-N removal efficiency of over 75% was attained. In addition, the up-flow process had higher removal efficiency in comparison to the down-flow process. Overall, this study provided a technical support for the removal of ammonia nitrogen from the micro-polluted source water, which had a referential significance when applied to other engineering projects.