稻秸酶解和沼气发酵臭氧氨水联合预处理技术研究

Effect of Ozone and Soaking Aqueous Ammonia Pretreatment on Enzymatic Hydrolysis and Biogas Fermentation of Rice Straw

对稻秸进行了臭氧氨水联合预处理提高酶解糖化和沼气发酵效率的实验研究,探索了臭氧氨水联合预处理对木质纤维素降解、单糖质量浓度、还原糖质量浓度和沼气发酵气体产率的影响。结果表明:臭氧氨水两步预处理进一步强化了脱木质素能力,有效提高了稻秸酶解糖化效率和沼气发酵产气率,增强了纤维降解利用率。酶解过程中,随着臭氧用量的增加,葡萄糖质量浓度先增加后降低,臭氧用量0.75 g/g时葡萄糖质量浓度最高,为36.92 g/L;氨水浸泡时间越长,还原糖质量浓度越高,氨水浸泡6 h的还原糖质量浓度为60.51 g/L。因此,酶解的适宜臭氧氨水联合处理条件为臭氧用量0.75 g/g和氨水浸泡时间6 h。对于沼气发酵,臭氧用量1.0 g/g和氨水浸泡时间9 h获得了较高甲烷产率,为165.39 mL/g,有效提高了稻秸产气效率和木质纤维素利用率。

The enzymatic hydrolysis and biogas fermentation of rice straw were studied. The effects of combined ozone and soaking aqueous ammonia pretreatment on the degradation of lignocellulose,monosugars concentration,reducing sugars concentration and biogas production were explored. The results showed that combined ozone and aqueous ammonia pretreatment further increased the delignification ability,improved the saccharification efficiency of rice straw and biogas yield,and enhanced the fiber degradation efficiency. During enzymatic hydrolysis,the glucose concentration was increased first and then decreased with the increase of ozone dosage. When the ozone dosage was 0. 75 g/g,the glucose concentration was the highest,as 36. 92 g/L. The longer ammonia pretreatment time was,the higher the reducing sugar concentration was,and the ammonia concentration for 6 h ammonia pretreatment was60. 51 g/L. Therefore, the suitable combined pretreatment conditions for enzymatic hydrolysis was0. 75 g/g ozone dosage and 6 h of soaking aqueous ammonia. For biogas fermentation,a high methane yield of 165. 39 mL/g was obtained with 1. 0 g/g of ozone dosage and 9 h of soaking aqueous ammonia time,which effectively increased the gas production efficiency of rice straw and utilization efficiency of lignocellulosic materials.