活性污泥-悬浮生物膜系统处理低C/N污水深度脱氮性能

Deep nitrogen removal performance of activated sludge suspended biofilm system for treating low C/N ratio wastewater

通过农业废弃物玉米芯悬浮生长生物膜的载体,构建了活性污泥-悬浮生物膜混合系统,以SBR工艺运行方式对低浓度低C/N污水的深度脱氮性能进行了研究.探究了挂膜启动阶段系统脱氮效果;在工艺稳定运行后,考察了温度、HRT、DO、进水C/N、进水pH等参数对工艺脱氮性能的影响.经过24 d挂膜后,结合污染物去除情况及镜检显示生物膜挂膜成功.运行结果表明,以预处理后的生活污水作为模拟原水,控制反应温度为26—30℃,HRT=8 h,COD/TN为(4.0±0.1),DO=(2.2±0.1)mg·L^(-1),进水pH=(8.0±0.1)的条件下,系统达到最佳运行条件,COD、NH_(4)^(+)-N、TN平均去除率分别为70.2%、94.8%和80.8%,平均出水COD、NH_(4)^(+)-N、TN浓度分别为14.89 mg·L^(-1)、0.57 mg·L^(-1)和2.40 mg·L^(-1).好氧阶段DO浓度对TN去除率有一定的影响,当好氧阶段DO浓度为(2.2±0.1)mg·L^(-1)时,TN去除率达到峰值84.38%.结果表明,活性污泥-悬浮生物膜混合系统处理低浓度低C/N污水具有优良性能,为低浓度低C/N污水的深度脱氮及玉米芯的资源化利用提供新的思路.

Agricultural waste corncob was used to construct an activated sludge-suspended biofilm mixed system.Deep nitrogen removal performance of low concentration and C/N ratio wastewater was studied in the SBR process operation mode.The nitrogen removal effect of the system at the start-up stage of biofilm formation was explored;when the process was at a steady stage,the effects of parameters such as temperature,HRT,DO,influent C/N ratio and influent pH on the nitrogen removal performance of the process were investigated.After 24 days,it showed that the biofilm was considered to be successfully formed combined with the removal of pollutants and microbial images of corncob.Pretreated domestic wasterwater was used as the simulated raw water and reaction temperature was controlled to be 26—30℃,HRT=8 h,COD/TN=(4.0±0.1),and pH of influent water was(8.0±0.1).The results showed that average removal ratios of COD,NH_(4)^(+)-N and TN were 70.2%,94.8%and 80.8%,respectively,The average effluent concentrations of COD,NH_(4)^(+)-N and TN were 14.89,0.57,2.40 mg·L^(-1),respectively.The DO concentration in aerobic phase had a certain influence on TN removal ratio.When the DO concentration in aerobic phase was(2.2±0.1)mg·L^(-1),the TN removal ratio reached a peak value of 84.38%.The above results showed that the activated sludge-suspended biofilm mixed system had an excellent performance in the treatment of low concentration and C/N ratio wastewater,which provided a new idea for the deep nitrogen removal of low concentration and C/N ratio wastewater and resource utilization of corncob.