Abstract: An experiment was carried out on anaerobic digestion of cow-dung (CD) and kitchen waste (KW) mixtures different in ratio under 37 ℃ for 50 days. Results show that (1)when the mixture was formed at a ratio of 1/2 and 2/1,its actual biogas production potential was 0.66 and 0.71 L·g^-1,respectively,calculated on the basis of volatile solids total mass,about 50% and 29% higher than its weighted calculation,respectively; (2)the mean methane concentration of the four treatments varied in the range of 50%-55% in ratio and their mean bioenergy yielded in the range of 18.92-20.81 MJ·m^-3;(3)among the four treatments,Treatment CD1/KW2 was the highest in biogas generating efficiency. The biogas it generated in the first 10 days and 20 days accounted for 55.4% and 92.2% of the total it yielded,respectively; (4)the ultimate biodegradability of the 4 treatments,i.e. CD,CD2/KW1,CD1/KW2 and KW,was 46.99%,53.31%,70.12%,and 66.25%,respectively.

Key words: cow-dung, kitchen waste, anaerobic digestion