Study On The Effect Of Different Anaerobic Fermentation Conditions On The Biogas Production Of Straw By Laccase Pretreatment

In recent years, the haze weather has become more and more serious, and the burning of craw straw is one of the important reasons. In China, the annual crop produceed about 700 million tons of staw every year. Most of the straw from ice straw, wheat straw and corn straw, but at present our country crops straw utilization rate is not high. Therefore, how to safely use the straw is the important measure to solve the problem of current environment haze. And the use of straw to produce methane is one of the feasible ways of straw harmless treatment. However, because of the straw cellulose, lignin content is high, making straw in biogas production process slow decomposition and degradation rate is low. Therefore, this study focuses on biogas yield of straw, slow start, low utilization rate, the cultivation ofrice, by using the selftraining of laccase pretreatment rice, corn straw, the outer structure of the lignin,cellulose composition of degradation, which is conducive to stalk anaerobic fermentation. Then according to the different conditions of anaerobicfermentation of anaerobic fermentation of straw, high gas production rate and utilization rate, In order to find the optimum processing conditions of straw.First, determine the best laccase pretreatment of straw added amount by adding different amount of single factor experiment:20 mL laccase and laccase dosage degradation effsct on rice, corn straw is the best. Rice straw cellulose degradation rate reached 33.2%, lignin degradation rate reached 31.6%, corn straw cellulose degradation rate reached 38.7% lignin degradation rate reached 38.9%.Secondly, straw after laccase pretreatment, according to the different anaerobic methanogenic fermentation condition experiments get the following results:In the different amount of urea anaerobic fermentation effect on rice, corn straw, rice straw supplemented with 1% urea (0.5 g) the best gas effect; maize straw addition of 3%(1.5 g) had the best effect on gas production of urea.In different amount of anaerobic fermentation of dairy manure effect on rice, corn strawin the removal of its gas production:the removal of part of the cow’s own gas production, with 20% of rice straw manure (10 g) of the best gas production; add corn stover 30% of cow dung (15 g) of gas works best.In the different amount of anaerobic fermentation of glucose effect on rice, corn straw:the amount of gas production of urea and urea for cow dung, straw gas is better than cow dung, therefore, choose the best amount of urea at the same time, the control of single factor variables for different:rice straw, in addition to 1%(0.5 g), rice straw supplemented with 5% glucose (2.5 g) had the best effect on gas production; for the corn straw, inaddition to 3%(1.5 g), maize straw addition of 3% glucose (1.5 g) had the best effect ongas production.Thirdly, electron microscopy(SEM), infrared spectroscopy(FTIR), mass spectrometry(MS) on straw test are as follows:Corn straw lignin and cellulose content is lower than that of rice straw lignin, cellulose content, and more stomata, which makes the anaerobic fermentation of corn stalk of the whole, than theanaerobic fermentation of rice straw and the effect of good.The CH4 content is about 57%, to meet the content range of biogas can be burned.