有机物污染场地浅层异位固化稳定化试验研究

发布时间：2018-06-24 10:01

本文选题：有机物污染 + 粉土质砂土　；参考：《岩土工程学报》2016年03期

【摘要】：以某化工企业有机物污染浅层土为对象,应用4种固化药剂进行固化稳定化修复对比研究。通过现场异位固化稳定化结合室内无侧限抗压强度、毒性浸出等试验,讨论了固化剂组份、龄期对其物理力学性质和浸出特性影响,并对比分析了其固化稳定化效果及机理。结果表明:随着养护时间增长,修复土p H值、毒性浸出溶液的有机物浓度降低,其中pH值由0 d的12.76~13.11降至28 d时的12.11~12.69,而有机物浸出浓度14d降幅在65%~100%间;干密度及无侧限抗压强度qu则稳步提高,其中干密度28 d增幅达14.4%~23.2%,而强度最大增加到122 k Pa。固化剂3和4修复污染土干密度较大,28 d密度超过1.37 g/cm~3,密实作用明显;添加固化剂会立即显著增大污染土pH值,其中固化剂4(电石渣+凹凸棒土)各龄期pH值明显大于其他剂型;各固化剂对不同有机污染物的稳定效果有所差别,但均能有效固化稳定化苯胺、2-氯酚、萘、苯、甲苯、邻-二甲苯;就污染物总体固化稳定化效果而言,含活性炭组分的固化剂1效果最为突出,其总稳定率接近100%;含水泥组分的固化剂2,3对土体的增强作用较好,其28 d强度可达109 k Pa以上。相较其他药剂,固化剂4在成本、能耗及污染物排放方面表现最优,且能较好满足场地修复对有机物稳定率及强度的要求,综合效果最佳,为优选的最佳剂型。
[Abstract]:In this paper, a comparative study on solidification and stabilization of organic pollutants in shallow soil of a chemical enterprise was carried out by using four kinds of curing agents. The effects of curing agent composition and age on physical and mechanical properties and leaching characteristics of heterotopic curing stabilizer combined with laboratory tests such as unconfined compressive strength and toxic leaching were discussed, and the effect and mechanism of curing stabilization were compared and analyzed. The results showed that with the increase of curing time, the concentration of organic matter in toxic leaching solution decreased with the increase of curing time, and the pH value decreased from 12.76 ~ 13.11 to 12.111.69 in 28 days, while the concentration of organic matter leaching decreased by 65 ~ 100% in 14 days. The dry density and unconfined compressive strength increased steadily, in which the dry density increased by 14.4and 23.2in 28 days, while the maximum strength increased to 122kPa. The dry density of the contaminated soil was more than 1.37 g / cm ~ (-3) in 28 days, and the effect of curing agent 3 and 4 was obvious, and the pH value of the contaminated soil was significantly increased with the addition of curing agent 3 and 4. The pH value of curing agent 4 (attapulgite) was obviously higher than that of other dosage forms, and the stabilizing effect of each curing agent on different organic pollutants was different, but all of them could effectively solidify stabilized aniline 2-chlorophenol, naphthalene, benzene and toluene. O-xylene; as far as the overall solidification and stabilization effect of pollutants is concerned, the curing agent 1 containing active carbon component has the most outstanding effect, and its total stability rate is close to 100%. The intensity can reach 109 KPA in 28 days. Compared with other medicament, hardener 4 has the best performance in cost, energy consumption and pollutant discharge, and can meet the requirements of site restoration for the stability and strength of organic matter. The comprehensive effect is the best and the best dosage form is selected.
【作者单位】：东南大学交通学院岩土工程研究所;江苏省城市地下工程与环境安全重点实验室;江苏圣泰环境科技股份有限公司;
【基金】：国家自然科学基金重点项目(41330641);国家自然科学基金项目(51278100,41472258) 江苏省自然科学基金项目(BK2012022) 国家高技术研究发展计划(“863”计划)项目(2013AA06A206)
【分类号】：TU470

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