响应曲面法优化微生物降解长焰煤工艺条件

摘要

选择4种细菌降解宝鸡麟游长焰煤,通过菌-煤匹配降解实验筛选出优势降解菌;在单因素实验的基础上,以接种量(A)、氧化程度(B)、降解时间(C)为自变量,以降解转化率为响应值,采用响应曲面法对多粘类芽孢杆菌降解长焰煤的工艺条件进行了优化研究.结果表明,优势降解菌为多粘类芽孢杆菌;影响降解转化率的多元二次方程模型为η=45.22+ 5.75A+10.24B+16.64C+ 5.43AC+ 5.35BC-7.84A2-9.67B2-13.02C2,R2=0.9779,失拟值为0.1565,失拟误差不显著;氧化程度和降解时间对降解转化率影响非常显著,接种量影响不显著,3个因素间的交互作用影响不显著;接种量、氧化程度、降解时间的最佳值分别为7.08 mL·(50mL)-1、7.58 mol·L-1、9.84 d,对应的最大降解转化率为59.14％,在此条件下进行验证实验得到降解转化率为58.87％,与模型预测值相差较小,表明所得模型能够较好地预测实际降解效果.%We screened a superior strain from four bacteria by degradation matching experiments of Baoji Linyou long flame coal.Based on single-factor experiment,using inoculum(A),oxidation degree(B),and degradation time(C) as variables,the degradation conversion rate as responsible value,we optimized the degradation conditions of long flame coal with Paenibacillus polymyxa by response surface methodology.The results indicated that the superior strain was Paenibacillus polymyxa,the multi-quadratic equation model was η=45.22+ 5.75A+10.24B+ 16.64C+5.43AC+5.35BC-7.84A2-9.67B2-13.02C2,R2 =0.9779,and the lack of fit was 0.1565,not significant.Meanwhile,we found the oxidation degree and degradation time were the significant factors for the degradation conversion rate,but inoculum and the interactions among three factors were not significant.The optimum values of inoculum,oxidation degree,and degradation time were 7.08 mL · (50 mL)-1,7.58 mol · L-1,and 9.84 d,respectively,while the corresponding degradation conversion rate was 59.14 ％.Under the optimum conditions,the degradation conversion rate of verification experiment was 58.87 ％,which was slightly different from the predicted value,furthermore,the obtained model was able to predict practical situation.