摘要
以北京某焦化厂苯精制车间废弃场地为研究对象,挖开10m×10m×4m的污染土基坑作为风险管控区,并进行微曝气阻隔技术处理,以期实现风险管控区的土壤气苯污染管控。结果表明,不曝气时,土壤中微生物主要为厌氧微生物。曝气1次不足以改变深层土壤的厌氧状态,对浅层土壤而言无法达到好氧微生物所需的足够O2,使得苯既不能被厌氧降解也不能被好氧降解,反而因扰动作用加速了苯的逸出,使得苯含量不减反增。再曝气3次后,各土层O2含量均大幅增加,污染土层中苯质量浓度降至0.79mg/m^3,而清洁土层中苯质量浓度全部降到了0.22mg/m^3以下,能够满足《污染场地挥发性有机物调查与风险评估技术导则》(DB11/T 1278-2015)土壤气中苯的筛选值(3.95mg/m^3)。
An abandoned benzol refining workshop in a coking plant in Beijing was chosen as the experimental object.A foundation pit measured 10 m×10 m×4 mwas excavated as a risk management area.Micro-aeration barrier technology was applied to control benzene in the area.Results showed that anaerobic microorganisms were dominant without aeration.Aeration for 1 time could not change the anaerobic condition of deep soil,and could not meet enough O2 for aerobic microorganisms,either.Therefore,benzene could not be degraded,but increased with the disturbance of aeration.Aeration for another 3 times,O2 increased charply.And benzene mass concentration in contaminated soil layer decreased to 0.79 mg/m^3,and those in clean soil layers all decreased to less than 0.22 mg/m^3,which met selected value(3.95 mg/m^3)of "Technical guideline for investigation and risk assessment of volatile organic compounds in contaminated sites"(DB11/T 1278-2015).
作者
万鹏
杨鹤峰
周四喜
魏宝莹
肖满
张石磊
钟茂生
WAN Peng;YANG Hefeng;ZHOU Sixi;WEI Baoying;XIAO Man;ZHANG Shilei;ZHONG Maosheng(CECEP DADI Environmental Remediation Co.,Ltd.,Beijing 100083;Beijing Municipal Research Institute of Environmental Protection,Beijing 100037)
出处
《环境污染与防治》
CAS
CSCD
北大核心
2020年第1期71-73,78,共4页
Environmental Pollution & Control
关键词
土壤气
微曝气阻隔技术
苯
污染场地
soil gas
micro-aeration barrier technology
benzene
contaminated sites
