干物质浓度对牛粪秸秆厌氧发酵产沼气的影响

Effect of Different Dry Matter Concentration on Dry Anaerobic Fermentation of Animal Manure and Straw

在发酵原料C/N=25～30,T=36℃的条件下,研究20%,15%,10%,5%和2.5%等5种干物质浓度对牛粪秸秆混合干式厌氧发酵产沼气性能的影响。实验结果表明:发酵前30d为产气高峰期,同时发酵渗滤液中的VFA浓度也较高;干物质浓度增加时,产气量波动增大,渗滤液中碱度和NH4+-N浓度升高,发酵装置的有机负荷率也较高;10%的干物质浓度产气效果最好,发酵前30d的累积产气量为4 710mL,相应的容积产气率可以达到0.313m3/m3.d。实验得到的结果对牛粪秸秆混合发酵的实际应用具有一定的指导意义。

In this paper anaerobic digestion of dairy manure and straw was conducted to produce biogas.Under the conditions of C/N=25-30 and T=36℃,five kinds of dry matter concentration of 20%,15%,10%,5% and 2.5% were tested to investigate the effect of dry matter concentration on anaerobic digestion.The result showed that first 30 days was the biogas production peak phase and VFA concentrations in the leachate were also high during the same period.When dry matter concentration increased,biogas production amount appeared larger fluctuation,and the concentrations of alkalinity and NH4＋-N in the leachate also increased with higher organic loading rate.Among five kinds of dry matter concentration 10% was more suitable for anaerobic digestion to produce biogas with total biogas production amount of 4710 mL after 30 days and volume biogas production rates of 0.313m3/m3·d.These results could provide instructive meaning to the engineering application of dry anaerobic digestion.