基于人工湿地的循环水产养殖系统工艺设计及净化效能

Technological design and purification performance of a recirculation aquaculture system based on constructed wetlands

该研究首次将复合垂直流人工湿地同池塘养殖结合．通过构建养殖-湿地生态系统，验证人工湿地对水产养殖用水和废水净化与回用的可行性。近9个月的新建人工湿地运行结果表明，水力负荷从313、469、625mm／d增加到781mm／d，人工湿地对TSS、CODcr和BOD5去除率的变动范围分别为80．5％～82．9％、45．2％～64．2％和61．0％～77．0％，对NH4^＋-N、NO3^-—N、TN去除率的变动范围分别为51．5％～67．8％、-90．6％～40．0％和29．1％～68．6％，对TP和IP的去除率为72．7％～89．1％和o～33．3％，对细菌总数、总大肠菌群、藻类等生命物质也有较好的去除效果，湿地出水水质除溶氢外能诀到国家渔业水质标准。初步结果表明人工湿地应用于水产养殖用水处理和回用具有广阔的前景。

How to purify and reuse the aquaculture water becomes a challenge problem to sustainable aquaculture in China, as well as in the world. Constructed wetland, acting as an ecological engineering alternative, is capable of reducing suspended solids, BOD, nitrogen, phosphorus and heavy metals from wastewater of many sources. The integrated vertical-flow constructed wetlands （IVCW） combined with pond culture to establish a new aquaculture-wetland ecosystem was firstly designed; the feasibility of IVCW for purifying and reusing polluted water and the effluent from fish cultivating ponds was evaluated. During the 9 months＇ operating period, the IVCW was operated at various hydraulic loading rates, 313, 469, 625 mm/d and 781 mm/d, the removal rates of TSS, CODcr and BOD5 were 80. 5%-82.9%, 45.2%-64. 2% and 61.0%-77.0%,respectively; Those of NH4^-N, NO3^--N and TN were 51.5%-67.8%, -90.6%-40. 0% and 29.1%-68.6%, respectively; TP and IP were 72.70%-89.1% and 0-33.3%; a good performance was also obtained for removing bacteria, total coliforms and algae. All parameters except dissolved oxygen of outlet from IVCW could meet the standard of national fishery water quality. The preliminary result shows that constructed wetlands for wastewater treatment and reuse in aquaculture have broad future.