Wastewaters from fish processing cause a high organic load for municipal wastewater treatment and can interfere with treatment operations due to their high oil and grease content. In the present study, a modular dissolved air flotation (DAF) unit was used to remove oil, grease and other suspended solids from fish processing plant wastewater. After DAF treatment, the residual particles and nutrients were adsorbed onto a mixture of hemp and spruce biochar in a pilot-scale column filtration system. The proposed integrated treatment process aims to improve the quality of the fish processing wastewater, facilitate water reuse, and recover the dissolved nutrients in a reusable form. The DAF treatment removed nearly all the oil and grease from the wastewater. Also, chemical oxygen demand, turbidity and phosphorus concentration clearly decreased during the DAF process. The biochar filtration further clarified the DAF-treated wastewater and partly adsorbed the residual nutrients. Furthermore, in the spent biochar mixture, the nitrogen and phosphorus content increased significantly (N to 9.1–10.5 mg/g, P to 0.32–1.38 mg/g), which indicates the improved properties of the biochar as a possible soil conditioner.

中文翻译：

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使用溶气浮选和中试规模生物炭塔过滤处理鱼类加工厂废水


鱼类加工产生的废水对城市废水处理造成高有机负荷，并且由于其油和油脂含量高，可能会干扰处理操作。在本研究中，使用模块化溶气浮选 （DAF） 装置去除鱼类加工厂废水中的油、油脂和其他悬浮固体。DAF 处理后，残留的颗粒和营养物质在中试规模的柱过滤系统中吸附到大麻和云杉生物炭的混合物上。拟议的综合处理工艺旨在提高鱼类加工废水的质量，促进水的再利用，并以可重复使用的形式回收溶解的营养物质。DAF 处理去除了废水中几乎所有的油和油脂。此外，在 DAF 过程中，化学需氧量、浊度和磷浓度明显降低。生物炭过滤进一步澄清了 DAF 处理后的废水，并部分吸附了残留的营养物质。此外，在废生物炭混合物中，氮和磷含量显着增加（N 至 9.1-10.5 mg/g，P 至 0.32-1.38 mg/g），这表明生物炭作为可能的土壤改良剂的性能有所改善。