该文在12％高同体质量分数和中温(35±1)℃条件下,开展了餐厨垃圾与污泥不同比例联合厌氧发酵对产气性能及发酵过程限速步骤影响的研究.结果表明,当餐厨垃圾与污泥二者比例为30∶30时,累积沼气产率、累积甲烷产率、生物转化产甲烷效率和VS(挥发性固体)去除率分别为612、327 mL/g、76.9％和63.6％,皆高于其他原料比例.混合底物中餐厨垃圾为主时,发酵前5d为产气高峰阶段,甲烷含量在整个发酵期间低于60％,挥发性脂肪酸(VFAs)抑制显著；而混合底物中污泥所占比例较高时,产气的高峰期多出现在第10～25 d,甲烷含量于发酵前5d迅速上升至50％后,缓慢提高并最终稳定在70％左右.混合底物中污泥所占比例的增加可提升沼气中甲烷含量,亦可明显缓解VFAs抑制作用.累积沼气产率随污泥比例的提高呈先上升后下降的变化.%Evaluation of high-solids anaerobic co-fermentation of food waste and excess sludge was conducted in laboratory scale, which operated at mesophilic (35°C±1°C) and high-solids (12% total solids) conditions. The effects of mixing ratios on biogas conversion and rate-limiting steps of high-solids anaerobic co-fermentation were discussed. Results showed that compared with other mixing ratios, a mixture ratio of 30:30 could obviously enhance the anaerobic efficiency of biogas production, and the cumulative biogas yield, cumulative methane yield, biodegradability as well as VS removal rate increased to 612 mL/gVS, 327 mL/gVS, 76.9% and 63.6%, respectively. Moreover, it was found that volatile fatty acids were mainly inhibition factor of multi-food waste case. The biogas production rate exhibited a rapid increase in earlier 5 days of co-fermentation, but the content of methane was still below 60% throughout the high-solids anaerobic co-fermentation. As far as the case of multi-sewage sludge, the peaks of biogas production rate were obtained from the 10th to the 25th day. It was also observed that methane content rapidly increased to 50% in earlier five days and then stabilized at approximately 70%.
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