Anaerobic fermentation of Ageratum for biogas production

Production of biogas from mixtures of fresh and partially-decomposed Ageratum with cattle dung were studied in batch digesters at 30 ± 1°C. Partially decomposed Ageratum produced 319·4 litres of gas per kg dry matter as compared to 222·4 litres of gas per kg dry matter from pure cattle dung. Fresh Ageratum supplemented with cattle dung in a ration of 3:2 (wet weight basis) did not produce any gas, because of the accumulation of excess acids. In contrast, similar mixtures of partially decomposed Ageratum and cattle dung yielded about 9% more biogas than did pure cattle dung. The methane contents of the gas obtained from Ageratum mixtures were 62–77% as compared to 56–60% from pure cattle dung.