Efficient bioreactor system for biological treatment and methane production from fish processing wastewater

The treatment of fish processing wastewater (FPWW) is a growing environmental concern due to its high organic load. Conventional treatment methods often fail to achieve high removal efficiencies or are too costly. This study addresses this gap by evaluating the performance of an up-flow aged refuse packed bioreactor (ARPB) for FPWW treatment and methane production. The bioreactor was packed with aged refuse and operated continuously at a flow rate of 2 L/day, a hydraulic load rate of 0.11 m3/m2*day, and hydraulic retention time of 5 days for 224 days, maintaining stable conditions (temperature 27 f 0.7 degrees C, alkalinity 339 f 40 mgCaCO3 and pH 7.3 f 0.2). The results demonstrated a 98 % COD removal and significant reductions in color, turbidity, and total dissolved solids. Methane production reached 266 f 7 mL CH4/gCOD, confirming the system's potential for sustainable energy recovery. This study presents the ARPB as a low-cost, efficient, and sustainable solution for biological wastewater treatment and renewable energy generation.