闭合循环水产养殖系统中生物过滤器的水处理效果研究

Performance of Biofilter in Closed Recirculating Culture Systems

对闭合循环水产养殖系统中生物过滤器生物膜的培养、处理能力等方面进行了研究。试验结果表明 ,在生产性试验阶段 :(1 )系统中添加培养液培养生物膜 ,水温在 2 0～ 2 2℃时需要 1 1 d,生物膜成熟后生物过滤器具有较强的转化能力 ;(2 )系统稳定后放养暗纹东方豚 ,连续运行 5个月 ,系统中 NH4- N浓度平均值为 0 .6 8mg/L ,NO2 - N平均值为 0 .5 8mg/L。在规模化生产阶段 :(1 )不预先培养生物膜 ,而直接放养饲养对象 ,这种情况下系统中的水质波动比较明显 ,NH4- N,NO2 - N浓度最高值分别为 2 .2 2 mg/L ,1 .1 2 mg/L ,经过 2个月的运行 ,分别降为 0 .4 7mg/L ,0 .1 4 mg/L ;(2 )在系统中加入 2 .5 mg/L的五倍子和 2 0～ 30 mg/L的生石灰均不影响生物过滤器的处理能力。加入 5 0 mg/L的福尔马林和 2 mg/L的土霉素对生物过滤器的处理能力影响比较明显 ;(3)生物过滤器对流经水体的NH4- N,NO2 - N,COD1次性去除率分别为 4 4.79%,2 0 .31 %,2 0 .1 0 %。

The effects of biofilter on water quality in closed culture systems were studied. The results indicated: (1) With culture solution added to the system, it needed 11 days for the biofilm to state, which had the buffer capability; (2) With fish breeding in the system for five months, the means of NH 4-N and NO 2-N were 0.68mg/L, and 0.58mg/L,respectively. (3) Introducing fish into the system without culturing biofilm, the fluctuations in water quality were more obvious. The highest concentrations of NH 4-N and NO 2-N were 2.22mg/L and 1.12mg/L,respectively (4) Adding 2.5mg/L WuBeizi and 20～30mg/L CaO to the experimental system could not influence the treatment capability of the biofilter, but 50mg/L formalin and 2mg/L oxytetracycline inhibited the nitrification of the biofilter. (5) The biofilter's lump-sum removal rates of NH 4-N, NO 2-N and COD were 44.79%, 20.31% and 20.1% respectively.