Abstract Cost-efficient, end-of-pipe, nitrate removal techniques are called for by the commercial aquaculture industry. This case study examined how simple flow manipulations improved the denitrification performance of a 19,007 m2 (13,305 m3) constructed, free water surface (FWS) wetland treating aquaculture effluent. The wetland consisted of two separate streams with a common outlet: one stream treating nitrate-rich but carbon deficient effluent from the production unit at a hydraulic retention time (HRT) of 1.5 days (wetland stream 1); and a second stream treating carbon-rich, fish sludge-based effluent at a HRT of 41.0 days (wetland stream 2). During the course of the study (May–July 2017), three increasing proportions (40, 49 and 56%) of nitrate-rich effluent were re-directed from wetland stream 1 to the sludge-fed wetland stream 2 aiming at improving heterotrophic denitrification conditions in wetland stream 2 and consequently nitrogen removal in the wetland as a whole. Inlet C/N ratio in wetland stream 2 decreased from 1086 ± 57 to an average of 234 ± 56 (p

中文翻译：

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利用鱼类废物改善水产养殖湿地的反硝化作用——案例研究

摘要 商业水产养殖业需要具有成本效益的末端硝酸盐去除技术。本案例研究研究了简单的流量操作如何提高 19,007 平方米（13,305 立方米）建造的自由水面 (FWS) 湿地处理水产养殖废水的反硝化性能。湿地由两个具有公共出口的独立流组成：一个流以 1.5 天的水力停留时间 (HRT) 处理来自生产单元的富含硝酸盐但碳缺乏的流出物（湿地流 1）；第二条河流以 41.0 天的 HRT（湿地河流 2）处理富含碳的鱼类污泥流出物。在研究过程中（2017 年 5 月至 7 月），三个增加的比例（40、49% 和 56%) 的富含硝酸盐的流出物从湿地流 1 重新引导到以污泥供给的湿地流 2，旨在改善湿地流 2 中的异养反硝化条件，从而在整个湿地中去除氮。湿地流 2 的入口 C/N 比从 1086 ± 57 下降到平均 234 ± 56 (p