大型污水处理厂恶臭气体成分及来源的现场实测研究

Investigation on the types and concentrations of malodorous gases emitted from wastewater treatment plants

污水处理厂散发恶臭气体的种类和浓度与工人的职业健康息息相关。首先通过文献综述对以往报道的污水处理厂不同处理单元散发的恶臭气体污染物种类和浓度进行了统计,然后以上海两座大型污水处理厂T厂和B厂为例,对其污水处理流程与污泥处理流程散发的恶臭有机污染物种类和浓度进行了测试和对比分析。结果表明,T厂和B厂污水处理流程中产生的污染物具有较高相似性,均以甲苯、四氯乙烯、十一烷、十二烷为代表的芳香烃、卤代烃和烷烃为主;污泥处理流程污染物组分差异较大,共同的高浓度污染物为三甲基戊烷,但这些污染物均未超过人体嗅觉阈值,仅甲硫醇和二甲基二硫浓度超过了嗅觉阈值。测试发现构(建)筑物安装密封盖板并设置科学的抽风除臭装置能够有效控制恶臭污染物向外散逸。将上海地区的污水处理厂与文献报道的国内外其他地区的污水处理厂恶臭污染物进行对比,发现地域差异性明显,上海地区的污染物浓度更高,但不同种类的有机污染物在总VOCs浓度中的占比相近。

The type and concentration of malodorous gases emitted by wastewater treatment plants are closely related to the occupational health of workers.Firstly,this paper makes statistics on the types and concentrations of odor pollutants emitted by different treatment units of wastewater treatment plants in the past through literature review,and then takes two large wastewater treatment plants T and B in Shanghai as examples to test and compare the types and concentrations of odor pollutants emitted by wastewater treatment process and sludge treatment process.The results show that the organic pollutants produced in the wastewater treatment process of plant T and plant B have high similarity,and they are mainly aromatic hydrocarbons,halogenated hydrocarbons and alkanes represented by toluene,tetrachloroethylene,undecane and dodecane;The components of pollutants in the sludge treatment process vary greatly,and the common high concentration pollutant is trimethylpentane.But these pollutants do not exceed the olfactory threshold of human body,and only the concentrations of methyl mercaptan and dimethyl disulfide exceed the olfactory threshold.The test found that the installation of sealing cover plate and scientific exhaust and deodorization device for structures(buildings)can effectively control the outward escape of odor pollutants.Comparing the odor pollutants of wastewater treatment plants in Shanghai with those in other regions at home and abroad reported in the literature,it is found that there are obvious regional differences.The pollutant concentration in Shanghai is higher,but the proportion of different kinds of organic pollutants in the total VOCs concentration is similar.