响应面法优化香蕉秸秆与猪粪混合厌氧发酵工艺研究

将香蕉秸秆与猪粪混合后厌氧发酵,考察粪秸比(猪粪干物质占发酵原料干物质的质量分数)、厌氧污泥接种量(厌氧污泥占发酵料液的质量分数)和发酵温度对总产气量的影响。在此基础上,通过响应面法对厌氧发酵工艺进行优化,并建立总产气量与粪秸比、厌氧污泥接种量、发酵温度的二次回归模型。研究结果表明,建立的二次多项式数学模型具有高度显著性,模型拟合度、精确度高,数据合理。最佳工艺条件为:粪秸比为35.34%,厌氧污泥接种量为61.40%,发酵温度为40.27℃。在此条件下,总产气量的预测值为15 779.2mL,试验值为15 620.5mL,二者相对偏差为1.01%。可见,所得模型能够较好地优化发酵条件并预测总产气量,可为提高香蕉秸秆与猪粪混合厌氧发酵产气量及提高发酵效率提供一定参考。

Optimization of anaerobic fermentation with mixed materials of banana straw and pig manure by response surface methodology

In this study,the effects of manure to straw ratio(mass fraction of dry pig manure in dry fermentation raw material),inoculums concentration of anaerobic sludge(mass fraction of anaerobic sludge in fermentation broth)and fermentation temperature on the total biogas production of anaerobic fermentation of mixed banana straw and pig manure were investigated.On basis of that,the anaerobic fermentation process was optimized by response surface methodology,and the quadratic regression model of total biogas production to manure to straw ratio,inoculums concentration of anaerobic sludge and fermentation temperature was established.The results showed that the mathematical model of quadratic polynomials was highly significant.The model had high fitting degree,high accuracy and reasonable data.The optimum conditions were determined as follows:manure to straw ratio was 35.34%,the inoculums concentration of anaerobic sludge was 61.40%,and the fermentation temperature was 40.27℃.Under these conditions,the predicted total biogas production was 15 779.2 mL,and the experimental value was 15 620.5 mL.The relative deviation was 1.01%.Therefore,the model could optimize the conditions of anaerobic fermentation and predict the total biogas production.This study could provide references for improving biogas production and fermentation efficiency of mixed anaerobic fermentation of banana straw and pig manure.