污水处理厂挥发性硫化物释放特征与风险评价

对城市污水处理厂各处理单元释放的挥发性硫化物（VSCs）进行长期监测，评估VSCs带来的感官效应和健康风险.结果表明，从浓度上看，VSCs以H₂S为主（监测期间的H₂S浓度为N.D.~580μg/m³），而甲硫醇（MT）的浓度占比最少（监测期间MT的浓度为N.D.~4.7μg/m³），同时VSCs的浓度分布具有明显的季节性，即夏季>秋季>冬季.在感官方面，H₂S是所有VSCs中气味贡献最大的气体（贡献率为79%~93%），除二沉池外，其在其他处理单元中均为关键性恶臭气体；虽然MT浓度水平低，但是其对气味的贡献不能被忽略；格栅、沉砂池混合气体气味活性值（SOAV）分别为2591.9、5494.8，预处理单元对该厂的气味贡献最大.在健康风险方面，春季和夏季时，格栅和沉砂池中的H₂S存在非致癌风险.

Release characteristics and risk evaluation of VSCs in municipal wastewater treatment plants

Volatile sulfur compounds (VSCs) released by each treatment unit of urban sewage treatment plants were long-term monitored, and the sensory effects and health risks brought by VSCs were evaluated. The results showed that, from the point of view of concentration, VSCs were dominated by H₂S (the H₂S concentration during the monitoring period was N.D.~580μg/m³), and the concentration of methyl mercaptan (MT) accounts for the least (the concentration of MT during the monitoring period was N.D.~4.7μg/m³), and the concentration distribution of VSCs had obvious seasonality, that was, summer>autumn>winter. In terms of sensory, H₂S was the gas the contributes the most to the odor of all VSCs (the contribution rate was 79%~93%), except for secondary sedimentation. Outside the tank, it was a key malodorous gas in other processing units; although the MT concentration level was low, its contribution to odor cannot be ignored; the odor activity value (SOAV) of the mixed gas of the grid and the grit tank were 2591.9, 5494.8, the pretreatment unit contributed the most to the smell of the plant. In terms of health risks, there was a non-carcinogenic risk of H₂S in the grille and grit tank in spring and summer.