餐厨垃圾两相厌氧发酵产甲烷相恶臭排放规律

为了研究餐厨垃圾两相厌氧发酵产甲烷相恶臭排放规律，在中温（35℃）条件下，以餐厨垃圾为发酵底物进行中试规模的两相连续式厌氧发酵试验，并对一个周期内不同时间段产甲烷相产生的气体进行采样，分析其臭气浓度和物质浓度，结合各组分的阈稀释倍数，筛选出主要的恶臭污染物。结果表明，在发酵系统稳定运行阶段，产甲烷相产生的臭气浓度较大，都在23万以上；产甲烷相产生的恶臭物质主要包括硫化物、萜烯类、含氧类和芳烃类四类化合物，其中质量浓度最高的恶臭物质是硫化氢，超过了150 mg/m3；产甲烷相的主要致臭物质是硫化物，其中贡献最大的是硫化氢，其阈稀释倍数都在26万以上，其次为乙硫醇﹥甲硫醇﹥乙硫醚，这3种物质的阈稀释倍数都在4 000以上；除了这4种硫化物，丁醛对恶臭的贡献也比较大，其阈稀释倍数也在4 000以上。

Odors emission characteristics in methanogenic stage of two-phase anaerobic fermentation of kitchen waste

In order to study odors emission characteristics in the methanogenic stage of two-phase anaerobic fermentation of kitchen waste,the continuous pilot-scale two-phase anaerobic fermentation experiments were conducted under mesophilic condition (35℃),using kitchen waste as fermentation substrates.The gases generated in the methanogenic stage were sampled at different time segments during a feeding cycle,odor concentration and component concentration were analyzed.The major odor pollutants were selected according to the threshold dilution of each component.The results show that the odor concentration was above 230 000 when the fermentor ran in steady state.Major odor pollutants are proved to be sulfides,terpenes,oxygenated compounds and aromatic hydrocarbons,among which hydrogen sulfide has the highest concentration of more than 150 mg/m3.The key odorants of the methanogenic stage are sulfides.Hydrogen sulfide makes the greatest contribution,its threshold dilution is more than 260 000,followed by ethyl mercaptan,methyl mercaptan and ethyl thioether,having the threshold dilution of more than 4 000.In addition to these four sulfides,butyraldehyde also makes a relatively large contribution,with the threshold dilution of over 4 000.