厨余和牛粪混合厌氧发酵产气性能试验研究

Biogasification performance of anaerobic co-digestion of kitchen residues and cattle manure

在中温(35℃)条件下,通过批式厌氧发酵对牛粪、厨余以及厨余和牛粪的混合物的产气性能进行了对比研究。结果表明,单独消化时,厨余的甲烷产量(以VS为基准)为362.2 ml/g,生物转化效率为60.2%,明显高于牛粪的144.3 ml/g和25.4%;混合消化时,由于发酵物营养平衡和C/N比得到改善,缓冲能力增强,因此混合消化效果要好于两者单独消化。在厨余/牛粪(质量比,下同)为11∶时,混合消化的协同作用最显著,对甲烷产量和生物转化效率的贡献率分别为17.3%和7.8%,消化时间缩短了9 d,说明混合消化是提高厌氧消化效率的有效途径。

The anaerobic batch fermentation of kitchen residues, cattle manure and their mixtures were studied at the mesophilic temperature of 35 ℃. Results showed that the digestion of kitchen residues obtained 362.2 ml/g of methane yield and the biodegradation rate reached a value of 60.2%, which were significantly higher as comparing with those of the digestion of cattle manure, which are 144.3 ml/g and 25.4%, respectively. The co-digestion of two wastes had better performance than single-digestion due to well-balanced nutrients, improved C/N ratio and stronger buffer capacity. When the ratio of kitchen waste to cattle manure was 1：1, the methane yield and biodegradation rate were increased by 17.3% and 7.8%, respectively, and the digestion time was shorten by 9 days, which were contributed by the synergic effect of co-digestion. It indicated that co-digestion was an effective way to enhance the digestion efficiency.