EFFECT OF SOLID LOADINGS ON BIOGAS PRODUCTION FROM THE CO-DIGESTION OF CORN STALKS WITH COW DUNG

Abstract

In an extension to our previous work where we investigated the anaerobic digestion of Corn stalk (CS) and Cow dung (CD) with co-digestion experiments at initial total solid loading of 37.5%. This paper has investigated the anaerobic co-digestion of CS and CD at lower solid loadings of 10%, 15 % and 20% TS. These experiments were also carried out at different substrate mixing ratios of CS-CD 1:1 and CS-CD 1:2. The anaerobic digestion was carried out in a digester designed and fabricated locally with retention time of 45 days. Results show a maximum Biogas Yield of 67.85L/Kg TS and 75.75L/Kg TS for 10%TS at CS-CD 1:1 and CS-CD 1:2 respectively. Experiments carried out at 20% TS showed the lowest Biogas Yield/Kg of 44.5L/Kg and 50.38L/Kg for CS-CD 1:1 and CS-CD 1:2 respectively. Results also showed that studies carried out at CS-CD 1:2 showed higher biogas yields for substrate concentrations of 10%, 15 % and 20% TS when compared to corresponding experiments carried out at a mixing ratio of CS-CD 1:1.