Abstract：
Dredging of lake sediment is a method to remove accumulated phosphorus and nitrogen in lakes and thereby reducing the risk of eutrophication. After dredging, the sediment is dewatered to reduce the volume. It is important to get a high dry matter content and ensure that the filtrate does not contain harmful compounds so it can be returned to the lake. A pilot-scale belt filter and flexible intermediate bulk containers (FIBC) were used for dewatering lake sediment with the sediment treated with a synthetic polymer or three different biopolymers. The goal of the study was to retain the phosphorus in the filter cake while returning the filtrate to the lake with a minimal phosphorus content. Results showed dry matter content of up to 16 % in the dewatered sediment and the sediment retained 96-99 % of the phosphorus. Furthermore, nitrogen was reduced by 27-71 % in the filtrate water. Toxicity tests found low ecotoxicity for most biopolymer filtrates, whereas synthetic polymer showed the highest potential ecotoxicity. Consequently, biopolymers provided satisfactory results, proving more environmentally friendly despite requiring longer filtration time.
摘要：
疏浚湖泊沉积物是一种去除湖泊中累积的磷和氮从而降低富营养化风险的方法。疏通后,将沉积物脱水以减少体积。重要的是要获得高干物质含量，并确保滤液不含有害化合物，以便将其返回湖中。使用中试规模的带式过滤器和柔性中间散装容器（FIBC）对湖泊沉积物进行脱水，并用合成聚合物或三种不同的生物聚合物处理沉积物。研究的目的是将磷保留在滤饼中，同时将滤液以最小的磷含量返回湖中。结果表明，脱水沉积物中的干物质含量高达16％，沉积物保留了96-99％的磷。此外，在滤液中氮气减少27-71%。毒性测试发现大多数生物聚合物滤液的生态毒性较低，而合成聚合物显示出最高的潜在生态毒性。因此,生物聚合物提供了令人满意的结果，证明更环保，尽管需要更长的过滤时间。
