Optimization of Methane Production Physical Pre-Treatment: A Comparative Study

The increasing energy demands worldwide has resulted in tremendous carbon dioxide emissions (depletion of fossil fuels).In order to ameliorate the problem of depletion of fossil fuel, it is essential an alternative source of energy which impacted little on the environment be developed. For this study, biogas was considered as renewable energy sources that can be brought forth from different types of biomass. The pre-treatment of the organic waste dwell on grass and cow dung. Primary objectives included decreasing environmental pollution, improving good health, encouraging the use of simple technology in advancing organic waste digestion to create alternative energy source. Milling, pre-oven heating and sieving was employed in the pHysical pretreatment by which substrate size was reduced. This method was used in comparing the processes of mesopHilic anaerobic co-digestion of cattle dung and grass. Evaluating biodegradability pretreated lignocellulosic biomass, 9-days batch anaerobic digestion experiments was used. The pretreatment method for grass resulted in 82% bio-methane yield with a cumulative CH4 production increasing from 1.3 to 1.5 nm3CH4/g/kg.This enhancement was most likely due to the resistance of cellulose and hemicellulose molecules in the plant cell wall to degradation by bacteria. The pretreatment .method for cattle waste resulted in 90% higher bio-methane yield with a cumulative CH4 production increasing from 2.8 to 3.0 nm3CH4/g/kg This was attributed to pre-heating of the organic waste of cow dung cellulose and hemicellulose. The TS for the grass were 0.0452, 0.478 and 0.480 (+0.02) (w/w) and VS was 0.173, 0.0179, and 0.0156 (± 0.02) including high increased in pH and alkalinity to 7.9 respectively. In the result, it was established that both biomass achieved similar biomass solubilization.