Effect of total solid concentration and temperature on biogas yields of mixture of chicken manure and corn straw

To determine optimal fermentation temperature and total solid concentration , as well as to explore the relationship among temperature, total solid concentration and biogas production, a simulation experiment using self-designed constant-temperature anaerobic fermentation equipment was conducted in indoor conditions. In this study, the mixture of chicken manure and corn straw at 2∶1(dry matter quantity) was used as the digestion material and the substrate of constant temperature fermentation pool was used as the inoculation substances, aiming at studying the effects of different total solid concentration of digestion material at different temperatures on gas production. The temperature ranged from 20 to 40℃ with a gradient of 5℃ and total solid concentration increased from 4% to 20% with a gradient of 4%. Results indicated that biogas production rate of different total solid concentration increased with temperature. With the increase of total solid concentration, the range of optional temperature of digestion material widened. The sequence of mean cumulative biogas production at different temperatures was 8%＞20%＞16%＞12%＞4%. The theoretical value of optimal total solid concentration and temperature of chicken manure mixed corn straw (2∶1) were 14.6% and 32.8℃.It can be concluded that biogas yields did not increase with the total solid concentration and different temperature has its optimal total solid concentration or the range of total solid concentration.