污泥干化过程中苯系物(BTEX)的释放及其致癌风险评价  

BTEX release and its carcinogenic risk assessment during sewage sludge dewatering

作　　者：褚赟[1] 翁焕新[1] 章金骏[1] 裘望 

机构地区：[1]浙江大学环境与生物地球化学研究所,杭州310027 [2]余杭环境保护局,杭州310000

出　　处：《环境科学学报》2009年第4期777-785,共9页Acta Scientiae Circumstantiae

基　　金：浙江省重大科技攻关项目(No.2005C13005);浙江省重点科技计划项目(No.2005C23051)~~

摘　　要：在模拟污泥干化的条件下,研究了4种类型污水污泥苯系物(BTEX)的释放特征及其影响因素.结果表明,在50～300℃的干化温度范围内,4种污泥的BTEX释放总量在4.20～161.90μg.m-3之间;在温度高于150℃之后,各类污泥中的BTEX释放量大幅增加;而低于150℃的情况下,污泥中BTEX的释放量仅占总BTEX释放量的5.09%.不同温度下污泥的BTEX释放量与其在污泥中的含量之间存在显著的线性关系.不同类型的污泥其所释放的BTEX组分之间具有较大的差别,污泥中BTEX的含量决定其所释放的数量,而其释放强度则取决于干化温度.对污泥释放BTEX进行健康风险评价表明,各类污泥在150～300℃下所释放的苯对暴露人员存在一定的致癌风险,其中女性相对于男性致癌风险更高.控制污泥干化温度可以最大限度地减少BTEX释放,进而降低致癌风险.Volatile organic compounds, such as BTEX （benzene, toluene, ethylbenzene, and xylenes）, emitted during industrial processing pose a potential inhalation health risk. We characterized the BTEX release from four types of sewage sludge under simulative dewatering conditions. Our results show that the total release of BTEX from four types of sewage sludge ranges from 4.20μg·m^-3 to 161.9μg·m^-3 at a temperature between 50℃ and 300℃. The BTEX emission rate increases significantly when the drying temperature reaches 150℃. Below 150℃ , the BTEX release accounts for only 5.09% of the total amount. We observed a significant linear relationship between the BTEX release and its content in sewage sludge at a certain temperature. The BTEX composition varies in different types of sewage sludge. The amount of BTEX released is determined by its content in the sewage sludge, whereas the rate of release is correlated with the temperature. Exposure to volatile BTEX released during sewage sludge dewatering process at temperatures above 150 C poses significant carcinogenic risk, particularly for female operators. Therefore, a strict control of temperature during sewage sludge dewatering is essential to reduce BTEX release and simultaneously minimize its potential health risk.

关 键 词：苯系物(苯 甲苯 乙苯 二甲苯) 污水污泥 干化 致癌风险评价 

分 类 号：X703[环境科学与工程—环境工程]