温度对4种不同粪便厌氧消化产气效率及消化时间的影响

Effects of temperature on biogas production efficiency and fermentation time of four manures

为研究温度和粪便厌氧消化产气效率及消化时间的关系,该试验通过自行研究设计的可控性恒温发酵装置,以猪粪、牛粪、鸡粪和人粪为消化原料,以常温厌氧发酵池的底物为接种物,在25～40℃温度范围内,以5℃为梯度,进行了批量厌氧消化试验,研究了不同粪便厌氧消化的产气量、消化时间和最优消化温度。结果显示,影响猪粪、牛粪、鸡粪和人粪厌氧消化的最优消化温度及相应的消化时间和最大干物质累积产气量分别为(35.9℃,81d,0.495L/g),(33.8℃,74d,0.398L/g),(32.2℃,73d,0.324L/g)和(25.1℃,84d,0.294L/g)。不同粪便厌氧消化在其最优消化温度范围内产气速率最大,产气量随着温度的升高而增大;当超出最优温度范围,产气速率减小,产气量下降。消化时间不是随着温度的升高而缩短,单一以温度来断定消化时间的长短是不切合实际的。

In order to investigate the relationships between the temperature and biogas production efficiency and digestion time of anaerobic digestion, experiments were conducted in a self-manufactured anaerobic fermentation device, and the pig dung, cattle manure, chicken manure, and human feces were used as the digestion material and the substrate of constant temperature fermentation pool as the inoculation substances, and with temperatures increasing by increments of 5℃ from 25～40℃. A batch of experiments were conducted to study the biogas yield, digestion time and the optimal temperature for anaerobic digestion of four kinds of manure. The results show thai the optimal temperature of four kinds of manure and the corresponding digestion time and cumulative biogas yield of dry matter were 35.9℃, 81 d, and 0.495 L/g for pig manure; .33.8℃, 74 d, and 0.398 L/g for cattle manure; 32.2℃, 73 d, and 0.324 L/g for chicken manure; and 25.1℃, 84 d, and 0.294 L/g for human feces, respectively. Different kinds of manure in the optimal digestion temperature range, biogas production rate was the largest, biogas yield increased with the increase of temperature, when the temperature range was beyond the optimal, but biogas production rate decreased and biogas yield dropped. The digestion time does not shorten with the increase of temperature. It is not realistic to judge the length of digestion time solely by the temperature.