Enhancing efficiency of biogas collection from industrial organic sludge

Abstract

Industrial organic sludge is the concern of society and government levels since this kind of sludge will lead to the pollution of groundwater, surface water, air and the invasion of the food chain, increasing the disease and causing the bad effects on health without collecting and treating thoroughly. For high organic pollutants in sludge, appropriate treatment technology to recover biogas, supply energy for demand of production and living, is one of the current and priority solutions. Research contents in this study were application of pretreatment by hydrolysis process and anaerobic sequencing batch reactor (ASBR) to enhance biogas recovery. The obtained experimental results by hydrolysis through the alkalization process demonstrated that COD removal efficiency reached 62%, collected methane gas increased 4.9 times (360ml/L) compared to confronting sample (directly digestion, without hydrolyzed phase), at pH of 12, for 12 hours of hydrolysis time and after 20 digestion days at room temperature (30 -350C). Research results on anaerobic digestion reactor at organic loading rate of 1,6 kg VS/m3.day showed that COD and VS removal effiencies can reach 61.59 – 62.24, 52.33 – 54.26%, respectively for 20 days. The methane yield obtained 0.343 – 0.402 m3CH4/kgVS (corresponding to 0.523 – 0.628 m3CH4/kg sludge).