污染土壤中硝基苯热脱附研究  

Thermal Desorption of Nitrobenzene in Contaminated Soil

作　　者：张攀[1] 高彦征[1] 孔火良[1] 

机构地区：[1]南京农业大学土壤有机污染控制与修复研究所,南京210095

出　　处：《土壤》2012年第5期801-806,共6页Soils

基　　金：国家自然科学基金项目(21077056);江苏省自然科学基金项目(BK2009315)资助

摘　　要：以南京黄棕壤和江西红壤为实验土样,通过实验室批量热脱附试验,研究了热脱附温度、热脱附时间、土壤含水率、初始浓度以及土壤类型等对污染土壤中硝基苯热脱附效率的影响。结果表明,当土壤含水率2%,硝基苯初始浓度165.54mg/kg,脱附温度300℃,脱附时间30 min时,硝基苯的热脱附效率为85.88%,处理后土壤中硝基苯残留浓度为23.37 mg/kg,远低于展览会用地土壤环境质量评价标准(HJ350-2007)(暂行)中的B级标准限值(100 mg/kg)。土壤含水率过高和过低都不利于硝基苯的脱附,当含水率为15%时,达到了最佳的热脱附效果。硝基苯初始浓度对其脱附效率有较大的影响,随初始浓度的增加,硝基苯脱附效率呈现增大的趋势。而土壤类型对硝基苯热脱附效率的影响较小,在实际修复过程中可以忽略。研究结果可为热脱附法修复硝基苯污染土壤的实际应用提供科学依据。Batch experiments were conducted to study thermal, desorption of nitrobenzene in yellow brown soil （Nanjing） and Red soil （Jiangxi）. The effects of thermal desorption temperature, time, soil moisture, initial concentration and soil type on thermal desorption efficiency of nitrohenzene were studied. The results showed that, when soil moisture was 2%, initial concentration was 165.54 mg/kg, the thermal desorption temperature and time were 300℃ and 30 min, the thermal desorption efficiency of nitrobenzene reached 85.88%, and the residual concentration of nitrobenzene in treated soil was 23.37 mg/kg, which was far less than B-level limit （100 mg/kg） of Standard of Soil Quality Assessment for Exhibition Sites （HJ 350-2007）. Besides, both higher and lower soil moistures were not in favor of nitrobenzene desorption from the contaminated soil. When the soil moisture was 15%, a maximal thermal desorption eff^ciency of nitrobenzene reached. The initial concentration of nitrobenzene in soil had a great effect on thermal desorption efficiency. With an increase of initial concentration, there was a trend that thermal desorption efficiency of nitrobenzene increased. At the same time, the results also showed that soil type hardly affected on thermal desorption efficiency of nitrobenzene, so the effect of soil type could be neglected in practical applications. The results provide some scientific bases for the remediation of soil contaminated by nitrobenzene using thermal desorption method.

关 键 词：硝基苯 热脱附 土壤 

分 类 号：X131.1[环境科学与工程—环境科学]