Design and development of an anaerobic bio-digester for application in sewage sludge digestion for biogas and bio-solids generation using Acti-zyme as bio-catalyst

Abstract

Anaerobic digestion for biogas production is vital in sewage sludge management. This paper focuses on the design and development of an anaerobic bio-digester that can be utilized for biogas production utilizing Acti-zyme as the digestion bio-catalyst from sewage sludge. A stainless steel lab scale biodigester with a capacity of 390 L/day and an operating efficiency of 75% was considered. The biodigester allowed for addition of both the Acti-zyme and sewage sludge, the removal of the biogas and bio-solids generated during the digestion process. Process and equipment safety was ensured by maintaining the temperature at 35°C, pressure at 1 atmosphere as well as ensuring the flow of the substrate was maintained at 75% to minimize as operational hazards. Agitation was maintained at 60 rpm for uniform mixing whilst pH was maintained at 7 for enhancing Acti-zyme activity. The anaerobic bio-digester can either be up scaled or downscaled for application in sewage sludge management using Acti-zyme.