Enhancement of biogas production from organic fraction of municipal solid waste (OFMSW) using acid pretreatment.

The effectiveness of acid pretreatment in enhancing the hydrolysis of complex organic matter and ensuing biogas generation from OFMSW was studied using one strong and one weak acid. Acid pretreatment (pH6 - pH1) of OFMSW was carried out using hydrochloric acid (HCl) and acetic acid (CH3COOH) for 24 hours before anaerobic digestion. Optimum treatment conditions were determined based on biogas yield and quantity of acid needed. Increase in biogas yield ranged between 13-29% compared to control when OFMSW was treated with HCl whereas the same varied between 8-16% in case of CH3COOH treatment. Highest biogas yield (389.5 ml/gVS) with methane content of 68.3% was obtained after pretreatment with HCl at pH 3.12 whereas for CH3COOH, highest yield (350 ml/gVS) with 67.4% methane was observed after pretreatment at pH 1.78. OFMSW characteristics after each pretreatment step and their variation during the course of anaerobic digestion was also studied. [ABSTRACT FROM AUTHOR]