Study On Optimization Of Biogas Fermentation Process At Low Temperature

With the rapidly development of China economy, improving people’s living standards, increasing energy consumption, energy crisis and environmental pollution is a serious impediment to economic development. Rural household with biogas is a ecological friendly type cycle economic development mode. Various energy ecological modes can be established by biogas. Rural household with biogas would use rural animal stool, farmland straw, and life sewage, as fermentation raw materials producing biogas. On the one hand, it can reasonable disposal rural animal stool, improved rural ecological environment, and biogas residue and slurry are efficient of farmland organic fertilizer; on the other hand, biogas also can relieve the pressure of rural energy shortage.In northern China, cold climate limits the use of digesters in winter, in order to improve this situation, the test mainly from the fermentation technology of substrate concentration, C/N ratio, vaccinations, feeding volume, feeding time, feed type and stirring frequency, to start up the research of single element and orthogonal experiment, optimize the biogas fermentation technic apply to low temperature.Experiments fulfilled under the condition of4℃, The conclusion was that, the main parameter of biogas fermentation process at low temperature as follows:substrate concentration for15%, and C/N ratio for27/1, inoculum volume for38%inputs to fermentation device and began to ferment, in fermentation to49th day filled plus cow dung, fill material volume for10%, and to a time/20days of stirring frequency for stirring, at the end of the experiments, simulation group get4729.7mL/3000mL of total gas, and get36%increase in total volume than the control group.The topic optimization of biogas fermentation at low temperature can increase gas production and methane content, helping to increase the utilization of methane-generating pit in the winter.