动物无害化处理厂恶臭污染特征及健康风险评价

Odor Pollution Characterization and Health Risk Assessment of An Animal Innocuous Treatment Plant

基于上海市某动物无害化处理厂恶臭产生源、排气筒和厂界的恶臭物质监测数据,探究无害化处理厂的恶臭污染特征,并进一步评估其对周边环境和人体健康的影响。结果表明:臭气主要来源于动物尸体腐败(焚烧车间)及污水处理微生物活动(污水站)。恶臭物质主要为硫化氢(H_2S)、氨(NH_(3))、二甲二硫和甲硫醇(最大浓度分别为5.710、2.462、0.659、0.292 mg/m^(3))。焚烧车间是主要的NH_(3)贡献源,污水站是主要的H_2S贡献源。排气筒和厂界恶臭物质浓度均满足DB 31/1025—2016恶臭(异味)污染物排放标准的限值要求。处理厂的主要致臭因子为H_2S、甲硫醇、二甲二硫和NH_(3)(最大阈稀释倍数分别为9 154、1 496、57和50)。对比监测数据发现,排气筒和厂界主要致臭因子存在除NH_(3)、H_2S和甲硫醇外的其他未纳入例行监测的低嗅阈值物质,后续应考虑增加例行监测因子和监测频次以更好地监控恶臭排放及影响情况。处理厂车间内环境恶臭物质浓度虽然低于职业接触限值,但仍存在非致癌风险(风险指数为4.481~1 956.440),应对车间内的有限空间严格管控,作业人员在进入时须配置防护装备,保障废气处理设施正常运行,防止泄漏,防范工作人员健康风险。

Based on the monitoring data of odor generation sources,discharge outfalls and boundaries of an animal innocuous treatment plant in Shanghai,its odor pollution characteristics were explored and its impact on the surrounding environment and human health was further evaluated.The results showed that the main sources of odor were the corruption of animal carcasses(incineration workshop)and the microbial activities of sewage treatment(sewage station).The main odor pollutants were hydrogen sulfide(H2S),ammonia(NH_(3)),dimethyl disulfide(C2H6S2)and methanethiol(CH_(3)SH),with the maximum source contents of 5.710,2.462,0.659 and 0.292 mg/m^(3),respectively.The incineration workshop was the major contributor of NH_(3),while the sewage station was the major contributor of H2S.The contents at the outfalls and boundaries satisfied the standards of DB 31/1025—2016 Emission Standards of Odor Pollutants.The main odor-causing factors were H2S,CH_(3)SH,C2H6S2 and NH_(3),with the maximum threshold dilution times of 9154,1496,57 and 50,respectively.Comparison of the monitoring data revealed that there were low olfactory threshold factors other than NH_(3),H2S and CH_(3)SH at the outfalls and boundaries,which were not included in the routine monitoring program.Subsequent consideration should be given to increasing the routine monitoring factors and monitoring frequency to better monitor the odor emission and its impact.Although the odor substance contents in the workshop were lower than the occupational exposure limit,non-carcinogenic risks were identified with the risk index ranged from 4.481 to 1956.440.The limited space in the workshop should be strictly controlled,and incoming operators should be equipped with protective equipment.The normal operation of the waste gas treatment facilities must be ensured,preventing leakage and protecting health risks from staff.