Biogas Production in a Variety of Sawdust and Cow Dung Mixtures Using the Intermittent Mixing Method

Abstract

Cow dung is livestock waste that is very useful for renewable energy sources. The acceleration of the gas rate in cow dung biogas fermentation can be accelerated by the addition of secondary material, sawdust is one of the organic materials that can accelerate the rate of gas production in the formation of cow dung biogas. This study used a mixture composition: (B1) 675 g cow dung and 0 g sawdust, (B2) 472.5 g cow dung and 202.5 sawdust, (B3) 450 g cow dung and 225 g sawdust, and (B4) 427.5 g cow dung and 247.5 g of sawdust by fermentation for 20 days. In the research process, measurements of pH at the beginning and at the end of the study, gas pressure, gas volume, biodigester temperature, production rate, methane gas content, and flame test were carried out. In this study, the pH values ranged from 7-7.5 and the biodigester temperature was 27.5-31°C. The results of this study indicate that an organic mixture with a mixture of sawdust can accelerate production faster than without organic sawdust. Optimal results are found in the variation of the organic mixture of sawdust with a mixture of 450 g cow dung and 250 g sawdust having the highest production rate of 281.72 ml/day.