球磨玉米秸秆高固体酶解工艺模拟及经济性分析

Simulation and economic analysis of high solid enzymatic hydrolysis of ball milled corn straw

基于球磨预处理玉米秸秆,研究不同固体加载量和酶加载量对酶解效果的影响。结果表明,球磨60 min后的玉米秸秆在10 FPU CTec2(以1 g底物计)、20%(质量分数)固体加载量下,葡聚糖转化率和木糖得率分别为98%和47.66%,总单糖质量浓度达到86.38 g/L。通过Aspen plus软件对年处理30万t玉米秸秆经球磨预处理及高固体酶解产糖过程进行工艺设计,模拟得到年产量112453.7 t糖,经济性分析结果表明:每吨糖的生产成本为2176.8元,在净现值为0、内部收益率为10%时,最低糖售价为3086.2元/吨,此时年平均投资回报率(ROI)为6.13%,存在一定的经济效益潜力。通过灵敏度分析可知,玉米秸秆价格、纤维素酶价格和总投资费用对糖售价的影响较大。由此可见,球磨预处理玉米秸秆高固体酶解产糖工艺对后续生物基发酵或生物质产品的规模化生产具有借鉴意义。

Based on ball milling pretreatment of corn straw,the effects of different solid loading and enzyme loading on enzymatic hydrolysis were studied.Results showed that the conversion of dextran and the yield of xylose were 98%and 47.66%,respectively,and the total monosaccharide concentration was 86.38 g/L under the condition of 10 filter paper unit(FPU)CTec2 per gram substrate and 20%(w/w)solid loading.The process design of ball milling pretreatment and high solid enzymatic hydrolysis of 300000 tons of corn straw was simulated by Aspen plus software.The annual yield of 112453.7 tons of sugar was predicted.The economic analysis results show that the production cost per ton of sugar is 2176.8 yuan.When the net present value is 0 and the internal rate of return is 10%,the minimum sugar price is 3086.2 yuan/ton.With this prediction,the average annual return on investment(ROI)is 6.13%,a certain promising for economic benefits.Sensitivity analysis shows that the price of corn stalks,cellulase and total investment costs have a greater impact on sugar prices.Studies have shown that the high-solid enzymatic hydrolysis of corn stalk pretreatment by ball milling to produce sugar has reference significance for subsequent bio-based fermentation or large-scale production of biomass products.