流化床生物滤器净化养鱼循环水技术研究

Technology Study on Fluidized Bed Biofilter Purify cutnre Fish Recirculation Water

为了降低投入和提高单位水体的鱼载量,需要选择高效的水净化方法。流化床生物滤器结合了普通生物滤器和活性污泥法的优点,当生物滤器中水向上流动时,滤料会成悬浮态,流化床生物滤器可以减少固定床生物滤器经常发生的阻塞问题,实验结果：1、研究、设计制造出了养鱼生产上应用的流化床生物滤器及其配套设施,提出并优化了设计参数；流化床生物滤器的单元水处理能力为30～50t/h。2、优选了天然多孔、价廉、易得、比重适宜流化稳定的载体,与固定床生物滤器比较,流化床生物滤器的硝化率和过流率为同等条件下固定床生物滤器3倍。3、本系统养鱼可节水85～90％,建设费用和占地面积可减少50％。载鱼量为25±2Kg/m^3时,流化床生物滤器进水氨氮浓度为1．3mg/l,亚硝酸态氮为0．068mg/l。流化床生物滤器出水中,氨氮浓度为0．20mg/l,亚硝酸态氮浓度为0．024mg/l,符合渔业水质标准。氨氮去除率80～95％,亚硝酸态氮去除率65％以上。

In order to decrease the cost and improve the fish production of per unit water. A new method of water treatment which having a good result of purification and a high loading rate need to be select. The fluidized bed biofilter technology combines the best features of both trickling filters and activated sludge suspended growth system.. The media materials become suspended in upflow water currents through the biofiher. Fluidized bed biofilter can reduce the clogging that often occurs in submerged fixed bed biofiher. The results showed that; 1. High-rate nitrification in a fluidized bed biofilter and recirculating water fish culture system is designed for industry apple scale. The optimization parameters were advanced. The unit of fluidized bed biofilter remove water 30-50m3/hr; 2. we choose the natural porosint, cheaper, facile fluidized media materials. The fluidized bed biofilter can reduce the clogging and channelization problem which often occur in fix bed biofiher. Compared with fix bed biofilter at same conditions, the nitrification and hydraulic loading rate of fluidized bed biofilter is as three times as which of fix bed biofilter. 3. The closed recirculating water fish culture system using fluidized bed biofilter improve treatment and cut costs. The capital investment required to construct a fluidized bed biofilter is under half that needed for the extensions to coventlonal biofilter. Maximum carps fish load is 25±2Kg/m^3 in dosed reeireulating water fish culture system, saving water 85 %-90 %. Fluidized bed biofilter influent total ammonia N 1.3mg/1 , nitrite N 0. 068 mg/1 and fluidized bed biofilter effluent total ammonia N 0. 2 mg/1 , nitrite N 0. 024 mg/I to satisfy water quality for fisheries. Total ammonia N removal rate is 80-95%0, nitrite N removal rate is over 65%.