Efficient tofu wastewater treatment with biofiltration using OPEFB-activated carbon

• Biofilter media arrangement impact the tofu wastewater treatment efficiency. • Designed biofilter demonstrates high adsorption capacity, effectively reducing turbidity, colour, and organic pollutants. • Significant reductions in turbidity, color, BOD, COD, and TSS were achieved. • Best results obtained using silica sand, activated charcoal, zeolite, and gravel with 20 cm activated carbon. • OPEFB-based biofiltration offers a cost-effective and sustainable solution for tofu wastewater management. This study evaluates the effectiveness of biofiltration in treating tofu wastewater using a biofilter system with various media combinations, including OPEFB-derived activated carbon. The aim was to investigate the impact of media arrangement and activated carbon thickness on the reduction of pollutants such as pH, turbidity, colour, BOD, COD, and TSS. A series of experiments were conducted with different media arrangements (i.e., silica sand, activated charcoal, zeolite, and gravel) and varying activated carbon thicknesses (i.e., 10, 15, and 20 cm). The results showed that the biofilter system significantly improved wastewater quality, with the best performance observed in the S1A3 treatment, which achieved the highest removal efficiencies of 79.39% for turbidity, 68.42% for colour, 60.42% for BOD, 76.14% for COD, and 71.11% for TSS. The study suggests that biofiltration using OPEFB-activated carbon combined with silica sand, zeolite, and gravel is a promising and cost-effective method for reducing pollutants in tofu wastewater. However, further optimization and additional treatment methods are needed to meet regulatory discharge standards, particularly for BOD, COD, and TSS. The findings contribute to the development of sustainable wastewater treatment practices, with potential applications in the tofu industry.