Analisis Pengaruh Resirkulasi Sludge terhadap Performansi Single Stage Semi Continuous Anaerobic Digester dengan Substrat Palm Oil Mill Effluent

Abstract

The effects of sludge recirculation and recirculation rate on the anaerobic digestion performance of Palm Oil Mill Effluent (POME) substrate were studied using a prototype single-stage semi-continuous digester by comparing sludge recirculation ratios of 100% (36 L/day) and 150% (54 L/day). It was found that the sludge recirculation rate of 150% was the most suitable design parameters, which resulted in the highest biogas production of 0.470 m³/day, with methane yield of 71%, and maximum methane production of 0.258 m³/day, corresponding to energy potential of 11.90 MJ/day and digester efficiency of 66.21%. The pH values were measured within 6.8–7.2, indicating better stability at the higher recirculation rate. Overall, higher sludge recirculation enhanced digestion performance and stabilize the digestion process. The findings of this study demonstrates that sludge recirculation can be a simple and low-cost mean for improving the eficiency of POME treatment using anaerobic digester and producing renewable energy.