STATISTICAL STUDY TO OPTIMIZE BIOGAS PRODUCTION FROM WASTEWATER TREATMENT USING ANAEROBIC DIGESTION

The efficacy of anaerobic digestion (AD) for biogas production and wastewater treatment has been widely acknowledged. This study sought to elucidate the influence of influent Chemical Oxygen Demand (COD), Hydraulic Retention Time (HRT), and UASB reactor temperature on the methane content (%CH4), a paramount indicator of biogas quality. Employing Aspen Plus simulation, a 2k factorial experimental design was implemented to analyze wastewater treatment and biogas generation. The influent is industrial wastewater from ethanol production, characterized by a pH of 5 and concentrations of COD, Total Suspended Solids (TSS), Total Kjeldahl Nitrogen (TKN), and Sulfate(SO42-) at 38,000, 8,000, 700, and 300 ppm, respectively. The operating range of parameters in the 2k factorial experimental design includes a COD range of 38,000 and 90,000 ppm, HRT of 24 and 96 hours, and UASB reactor temperatures of 30 and 38 °C. The findings unequivocally demonstrate that HRT exerts the most significant impact on %CH4 content. Prolonged HRT facilitates enhanced organic compound degradation, thereby optimizing CH4 production efficiency through ample substrate conversion. Elevated influent COD levels also contribute to increased CH4 yield by augmenting the available organic matter.