| The realities that the agricultural ecologies and environments were destroyed, the agricultural pollution were more serious and the increasing of the peasants' income were tardy, put new forward to the anaerobic fermentation technologies which were benefit to both environment and economy. The anaerobic fermentation technologies could provide biogas for the farmer as the energy for life, reducing the pollution of dung to rural environments, and organic manure for agriculture, decreasing occurrence of pests and diseases and the inputs such as fertilizers and pesticides, so then to promote the development of plantation and cultivation and efficiency of agriculture as well as farmers income. Therefore, it is remarkable benefit to energy, economy and environment protection to robustly develop the anaerobic fermentation technologies.The fermentation with single material has been well studied and applied as a mature technology in production and life, but the fermentation with mixture materials, which was limited in the study of two materials, were few involved in three or more materials mixture. To improve the yield of biogas and the efficiency of the use of agricultural wastes, this research was carried out in controllable constant–temperature fermented equipment, selected cow dung, chicken dung, crops straw ( rice straw, wheat straw and corn straw ) with the proportion of TS ratio (0:2:1,0.4:1.6:1,0.8:1.2:1,1.2:0.8:1,1.6:0.4:1,2:0:1) as raw materials, and operated the experiments of biogas fermentation at 15℃,20℃,25℃and 30℃. The main results obtained in this paper were listed as the followings.(1) With the rise of temperature, the production rate of three kinds of materials group all increased at first, and then decreased at different temperatures except 15℃; The peak values were also increased with the temperature rise. With the increase of cow dung proportion of TS ratio, the time of peak appearance of cow dung, chicken dung and rice straw group was later at the same temperature, but the peak values were no regularly changes; the changes of peak appearance time as well as the peak values of material groups of cow dung, chicken dung, wheat straw and cow dung, chicken dung, corn straw were not obviously regularity.(2)The fermentation cycles of different material groups as well as different proportions were all significantly affected by the temperature and were longer at 15℃than other temperatures; The proportions of material groups of cow dung, chicken dung, rice straw and cow dung, chicken dung, wheat straw both significantly affected the fermentation cycles, but the group of cow dung, chicken dung, corn straw not.(3)The different temperatures and proportions as well as their interaction effect significantly affected the cumulative biogas yields. The cumulative biogas yields were all increased in three groups with the temperature rise except the R1 and R6 in group of cow dung, chicken dung, wheat straw and the R1 and R4 in group of cow dung, chicken dung, corn straw. Except that R4 less than R3and R5 at 25℃, R2 less than R1 at 35℃in group of cow dung, chicken dung, rice straw, no significance at 15℃in group of cow dung, chicken dung, wheat straw and no significance between R6 and R3, R4, R5 at 15℃and R4 less than R3,R5 at 20℃in group of cow dung, chicken dung, corn straw, with the increase of cow dung proportion of TS ratio, the cumulative biogas yields showed the trends that increased at first, and then decreased.(4) Predicted by the response surface models, with the optimal combination, the temperature 40℃and the TS ratio of cow dung, chicken manure and rice straw 0.9:1.02:1, the cumulative biogas yield is expected to reach maximum 40627.8mL; the temperature 40℃and the TS ratio of cow dung, chicken manure and wheat straw 1.22:0.78:1, the cumulative biogas yield is expected to reach maximum 39715.8mL; the temperature 40℃and the TS ratio of cow dung, chicken manure and corn straw 1.16:0.84:1, the cumulative biogas yield is expected to reach maximum40730.4mL.
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