The Comparative Study Of The Effect On Dry Anaerobic Fermentation For Corn Stalks With Different Pretreatment Methods

Dry anaerobic fermentation technology has been used widely as an ideal solid organic waste disposal way in recent years. However, the anaerobic fermentation of solid organic waste is a very intricate biochemical process, which is limited by many factors. Among them, the material has great impact on the anaerobic fermentation process. Because the crop straw has high fibrin content, and anaerobic microbial degradation of cellulose digestion is slow, leads to lower the efficiency of anaerobic digestion and limits the crop straw dry anaerobic fermentation process. Therefore, how to pretreat the crop straw to change the chemicophysical properties and optimize the anaerobic digestion is a very important topic. Based on a large number of domestic and international data, using the corn stalk which is the largest output in Northeast region as the research object. This research used physical, chemical and biological methods to do pretreatment, and then did the dry anaerobic fermentation after the pretreatment of corn stalk to investigate the influence of different pretreatment methods on anaerobic digestion.On the first step, corn stalks were treated by using of physical, chemical and biological methods to compare the quality of pretreatment, analyzed the content of reducing sugar, organic composition, and cellulose structure. And then used the pretreated corn stalk to do dry anaerobic fermentation, tested the micro-organisms utilization in different condition of TS and temperature. The study shows that pretreatment process with different processing, corn stalks fiber structure can be damaged to various degrees. The hemicelluloses removal rate up to 74% with dilute sulfuric acid treatment, and the lignin removal rate up to 84% with dilute hydroxide sodium treatment. Cellulose-degrading bacteria can also damage the internal structure of the fiber and lignin package function.The dry anaerobic fermentation using the material which has been pretreated showed that as the rising of fermentation temperature, the gas production rate, methane content and the organism treatment efficiency raised too. In different fermentation conditions for the pretreatment of corn stalks, the treatment with cellulose-degrading bacteria of corn stalks had the highest fermentation efficiency, the total gas production reached 20m³Â·m^-3, methane content up to 85%.