Techniques for Siloxanes Removal from Biogas Produced by Sewage Sludge Digestion

Abstract

Biogas production from sewage sludge digestion is one of the most effective methods for sewage sludge recycling. During the transformation from biogas to biomethane, the unfavorite component must be removed. As a trace amount of undesirable component, the siloxanes in biogas will damage the biogas power generation equipment, which is disadvantage to the biogas utilization. This paper stated the characteristics of siloxanes and the siloxanes removal technologies. The siloxanes removal technologies from biogas, including adsorption on solid material, gas-liquid absorption, condensation, membrane separation, biological treatment, were reviewed and compared. Otherwise, the pre-aeration on anaerobic digestion of sludge was introduced as an alternative for siloxanes removal before digestion.