竹子填料海水曝气生物滤器除氮性能

Pilot study on ammonium removal efficiency and nitrifying bacteria variety in marine biofilter charged with bamboo substrate

中文关键词: 海水生物滤器  竹子填料  氨氮去除  硝化细菌  养殖废水

英文关键词: Marine biofiltersBamboo mediumNH+4-N removal Nitrifying bacteriaAquaculture wastewater

中文摘要:

      生物滤器是循环水养殖系统的关键水处理单元，主要用于去除水体中水溶性的氮化物。采用人工模拟海水养殖废水，在系统运行的水力停留时间HRT为1h，水温为18～25 ℃，气水比为3∶1，初始C/N＝3∶1，pH为8.05～8.53条件下，对竹子填料浸没式生物滤器的挂膜过程和稳定运行阶段系统去除氨氮的运行特性，以及挂膜过程中的硝化细菌群落变化进行了实验研究。结果表明，在较低的NH+4 N浓度条件下，采用竹子填料的生物滤器有较快的挂膜速度，挂膜成功后滤料表面上生长的氨氧化细菌和亚硝酸氧化细菌的数量分别为4.5×105、1.5×105（光面）和1.1×106 CFU/ml（粗面）。具有较高且稳定的氨氮去除效果，氨氮去除效率达到80％，出水浓度小于0.06 mg/L，满足海水循环养殖系统中的应用要求。

英文摘要:

      Biofilter is the key water treatment unit of marine RAS(Recirculating Aquaculture System), and it plays an important role in water soluble nitrogen removal. A pilot scale experiment study was systematically carried out with synthetic aquaculture wastewater. The performances of ammonia removal in start up and steady state period were examined in the marine biofilters packed with bamboo medium. The hydraulic retention time, temperature, gas/water ratio, C/N and pH were 1 hour, 18~25℃, 3∶1, 3∶1 and 8.05～8.53, respectively. Results showed that marine biofilter packed with bamboo substrate enabled the nitrifying bacteria to grow rapidly, and the number of ammonia oxidizing bacteria and nitrite oxidizing bacteria was 4.5×105 CFU/ml、1.5×105 CFU/ml（smooth） and 1.1×106 CFU/ml（crude） in steady state period, respectively. The ammonia removal rate of biofilter was highly efficient. The ammonia nitrogen concentration in the effluent of bamboo biofilters was below 0.06 mg/L, which was much lower than the toxic leve