Study On Features And Influencing Factors Of Biogas Fermentation With Different Raw Material

With the continuous expansion of the scale of animal husbandry,provided a huge development space for biogas project. The livestock manure used for produce biogas, can not only solve the pollution of livestock manure to the environment, but also to achieve the reuse of waste resources. The livestock manure was only fermentation materials in actual biogas project. Such livestock manure has less easily degradable substances and nutrients, resulting in low volume production through anaerobic fermentation. In order to solve this problem, containing high carbon content of straw class crop in livestock manure, as well as provide a way of using the reduction and recycling of the straw.In this experiment, cow dung and wheat straw as raw materials, research the influence of gas production of single cow dung and cow manure and wheat straw on dry matter quality 2:1 mixed cow manure and wheat straw pretreated by dry mass 2:1 mixed anaerobic fermentation in different TS conditions, then found the best technology conditions. The research conclusions are as follows:(1) Cow manure blend with wheat straw or wheat straw pretreatment on biogas production ability of anaerobic digestion is much better than that of single anaerobic fermentation of cattle manure in the same TS. TS=7.36%, the gas production of mixed anaerobic fermentation is 1.63~1.71 times higher than that of single anaerobic fermentation of cattle manure; TS=7.36%, the biogas production of mixed anaerobic fermentation is 2.01~2.04 times higher than that of single anaerobic fermentation of cattle manure;(2) After pretreatment of wheat straw and cow dung mixed anaerobic fermentation can accelerate organic matter in raw material degradation and biogas production, advantageous to shorten the production cycle.(3) Increase the TS of fermentation raw materials, biogas production increased while reducing the level of utilization of raw materials. In this contrast experiment, have the same volume of fermentation liquor: the biogas production of TS=10% was 16% higher than that of TS=7.36%, biogas production rate decreased by 26% when single cow dung anaerobic fermentation; The biogas production of TS=10% was 44% higher than that of TS=7.36%, biogas production rate decreased by 8.2% when Cow manure and wheat straw mixed anaerobic fermentation; The biogas production of TS=10% was 45% higher than that of TS=7.36%, biogas production rate decreased by 8.4% when Cow manure and pretreatment wheat straw mixed anaerobic fermentation.(4) Contrasted the change range of pH value of each group was found: Single anaerobic fermentation of cattle manure pH change minimum, cow dung and wheat straw mixed anaerobic fermentation times, cow dung and pre processing wheat straw mixed anaerobic fermentation of the most significant, was acidified trend.(5) C element in the fermentation of raw materials after a series of complex biological and chemical reaction, transforming C elements only 24%~42% to biogas, which, TS=7.36%, have 56.81%~57.14% conversion to CH4 in, TS=10%, 52.22%~54.07% conversion to CH4 in,the remainder of the C element is partially used by microorganisms, and the portion of the component is deposited at the bottom of the fermentation tank with the reaction.(6) In actual engineering application of enlightenment, in order to obtain the maximum average daily gas production, fermentation tank every completely refueling and refueling time interval:A single cow dung, cow dung and wheat straw mixed with cow dung and pre processing of wheat straw mixed fermentation are well controlled in the range of 7 to 10, 15-18, 9 days.