微曝气阻隔技术处理污染场地土壤气中苯的研究  

Study on treatment of benzene in soil gas from contaminated sites by micro-aeration barrier technology

作　　者：万鹏 杨鹤峰 周四喜 魏宝莹 肖满 张石磊 钟茂生[2] 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)

机构地区：[1]中节能大地环境修复有限公司,北京100083 [2]北京市环境保护科学研究院,北京100037

出　　处：《环境污染与防治》2020年第1期71-73,78,共4页Environmental Pollution & Control

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).

关 键 词：土壤气 微曝气阻隔技术 苯 污染场地 

分 类 号：X53[环境科学与工程—环境工程]