Water Quality Changes in Artificial Effluent after Polymer Flocculant and Ozonation Treatment in Freshwater Recirculating Aquaculture System

As the demand for environmentally friendly aquaculture systems increases, it is essential to establish effective treatment methods for wastewater produced. Accordingly, an evaluation was conducted on the water quality changes resulting from the treatment of wastewater from recirculating aquaculture systems using polymeric flocculants and ozone. The flocculant was introduced into the wastewater at concentrations of 2-10 μL/g TSS, followed by ozone treatment of the supernatant after flocculant treatment at ozone loads of 12.5-300 mg O3/g TSS. The study observed differences in particulate matter and water quality concentrations based on the levels of flocculant treatment, with the most effective treatment noted at a condition of 4 μL/g TSS of the flocculant. Moreover, the size of particulate matter in the treated wastewater was mostly above 100 μm, indicating significant potential to enhance the performance of physical filtration systems, especially when considering the typical pore size of such systems. The ozone treatment showed the most efficient results under conditions of 37.5 mg O3/g TSS, suggesting that a combined approach of filtration using polymeric coagulants and geotextile bags, along with ozone treatment, could be applied as an eco-friendly means of wastewater treatment, minimizing pollution loads to the external environment.