猪粪与餐厨废弃物混合厌氧消化工艺优化研究

A process optimization of anaerobic co-digestion of pig manure and food wast

以猪粪和餐厨废弃物为主要原料,采用统计软件Design-Expert 7.0.0的响应面方法中的Box-Benhken设计模式,分析比较了厌氧发酵过程中两种物料的原料配比、p H、TS浓度3种因素对产气量的影响,拟合出一个三元二次多项式方程。研究结果表明,原料配比与p H的交互作用极显著,原料配比和TS的交互作用极显著,p H和TS的交互作用显著;在试验考察范围内,单个因素对产气量的影响顺序为TS>p H>原料配比。通过对方程的回归分析,得出混合发酵的最优工艺条件:原料配比为1∶1,p H为7.11,TS为10.08%,模型理论预测该条件下产气量为30 459.5 m L。经过模型验证试验,产气量的预测值和实测值的相对误差很小,表明模型拟合良好。

Pig manure and food waste as the main raw materials,were used for methane production in anaerobic digestion experiment. According to the comprehensive analysis and comparison about the effect of these three factors： p H,material ratio and TS concentration of pig manure and food waste on gas production, a ternary quadratic polynomial equation was established by using the Box-Benhken design mode of the response surface methodology of the statistical software Design 7.0.0. The results showed that the interaction of raw material ratio and p H,and raw material ratio and TS concentration were extremely remarkable, the interaction of p H and TS concentration was remarkable. While from the single factor in the test range,the order of effect of each factor on gas production was： TSp Hthe ratio of the materials. Basing on the analysis of regression equation,got the optimal process conditions of gas production by mixed fermentation,which as followed： raw material ratioof 1∶1,p H of 7.11,TS of 10.08%,and model theory predicted the gas production was 30 459.5 m L under the conditions. Through validating model experiment,the small relative errors between forecast value and measured value of gas production indicated that the model fitted well and had certain value of reference in practical application.