Research On The Green Process Of Fuel Butanol Production From Straw

With the depletion of fossil fuels,it is crucial to rebuild a sustainable renewable energy production,butanol has great advantages for reducing environmental pollution and the application of biomass agricultural waste.This paper analyzes the problems of high cost of enzyme preparation and difficulty of wastewater reuse in the current process of producing fuel butanol from straw,and uses different methods to optimize the production process so as to increase the efficiency of fuel butanol production and reduce the cost of the process.The specific work is as follows:(1)After fermenting the slag obtained from pretreatment of straw under different buffer salts,the optimal buffer salt was selected as butyric acid buffer salt.The optimal concentration of butyric acid was 25 mmol/L,and the concentration of fermentation product was determined.The butanol was 10.5 g/L,and the total acetone-butanol-ethanol(ABE)concentration was 14.3 g/L.Compared to the commonly used citric acid buffer salt,the ABE yield was increased by 10.7%.(2)After compounding with the three-enzyme system optimization,the final T1:T1-X:T1-AA9 tri-enzymes have the highest glucose and total sugar concentration and the glucose concentration when the ratio of the protein is about 40:20:40.Glucose was 28.84 g/L,xylose was 10.71 g/L,total sugar was 39.55 g/L,and total sugar yield was increased by 9.7%.(3)The optimal surfactant is Tween 40,the optimal addition amount is 2%(v/v),the optimal addition amount of xylanase and laccase is 2 g/L,metal lithium ion pair enzyme The best effect of the solution is promoted.The optimal concentration of lithium ion is 4 mmol/L.Adding 5 mg/L bovine serum albumin by batch feeding can significantly increase the glucose and total sugar yield.When the optimized multifactorial mixing is added,it can The cost of the enzyme preparation was reduced to a minimum of 452.5 yuan per ton of glucoase preparation cost,357.8 yuan per ton of total carbohydrase preparation,a final glucose concentration of 88.59 g/L,and a total sugar of 111.26 g/L.However,the glucose conversion rate was reduced from the initial 92.3%to 66.67%,and the xylose conversion rate decreased from the initial 55.74%to 28.29%.(4)Butanol Fermentation Wastewater(BFW)recovery method for butanol fermentation was developed.Alcohol production decreased from 7.2 g/L to 5.6 g/L,yield decreased by 22.2%,BFW emissions to a final drop to 56%after permeation of the fermentation for 4 cycles.The side recovery rate is higher than 4%,which can greatly reduce energy and BFW treatment costs.(5)Developed and validated a method for the reuse of fermentation wastewater and activated carbon adsorption wastewater.Butanol fermentation-pervaporation Separation-Rhizomonas yeast fermentation can be reused for at least six batches.However,the yield of butanol and oil during the recycling process is not significant.With the decrease,the final butanol concentration was 9.38 g/L,the ABE concentration was 14.01 g/L,butanol production was reduced by 13.9%compared to the first batch of fermentation,and the amount of wastewater was reduced to 23.4%.The current best adsorption activated carbon is selected as AR activated carbon,and the butyric acid obtained in static adsorption has competitive adsorption for the adsorption of acetic acid by activated carbon.By optimizing the optimal dynamic adsorption conditions,the adsorption of acetic acid and butyric acid after adsorbing the fermentation wastewater by excess activated carbon is eliminated.The rate reached 100%.The remaining product butanol concentration and ABE concentration after fermentation of the remaining wastewater were 11.2 g/L and 16.6 g/L,respectively,which was consistent with the normal fermentation results.The method was feasible.