多硫化钙固化高浓度铬污染软土的试验研究
PDF下载 (3364)倪家琪,陈 航,王 艳.多硫化钙固化高浓度铬污染软土的试验研究[J].宁波大学学报(理工版),2021,34(2):68-72.DOI:
NI Jiaqi,CHEN Hang,WANG Yan.Experimental study on highly concentrated chromium contaminated soft soil solidified with CaSx[J].Journal of Ningbo University(Natural Science & Engineering Edition),2021,34(2):68-72.DOI:
| Title: | Experimental study on highly concentrated chromium contaminated soft soil solidified with CaSx |
| 作者: | 倪家琪, 陈 航, 王 艳 |
| Author(s): | NI Jiaqi, CHEN Hang, WANG Yan |
| 关键词: | 固化; 高浓度铬; 污染软土; 无侧限抗压强度; 毒性浸出 |
| Keywords: | solidification; high concentrated chromium; contaminated soft soil; unconfined compressive strength; toxic leaching |
| 分类号: | TU43 |
| 文献标识码: | A |
| 摘要: | 为探究多硫化钙对高浓度铬污染软土的固化稳定效果, 进行了无侧限抗压强度和毒性浸出试验, 研究养护龄期、重金属浓度以及多硫化钙固化剂掺量对铬污染软土固化特性的影响. 研究表明: 固化土的无侧限抗压强度随着龄期的增加显著提高, 龄期28 d时的固化土体强度可为龄期7 d时强度的2.4倍; 污染土中铬浓度越高, 无侧限抗压强度越低; 掺加固化剂的污染土无侧限抗压强度有明显的提高, 当固化剂掺量为0.1%时, 强度可提高28%, 最大强度可达1.76 MPa. 掺入固化剂后, 铬的浸出浓度明显低于未掺固化剂时的浸出浓度, 固化剂掺量越高, 浸出浓度越小; 当铬的质量分数高达15000 mg●kg-1, 固化剂掺量为0.3%时, 铬浸出质量浓度仅1.67 mg●L-1. 提高固化剂的掺量对于固化稳定效果提升明显, 当固化剂掺量为0.3%时, 污染土的固化率在80.1%~98.9%之间. |
| Abstract: | In order to investigate the solidification and stability effect of CaSx on highly concentrated chromium contaminated soft soil, unconfined compressive strength and toxicity leaching test were carried out, and curing time, chromium concentration and dose of CaSx were considered. The results show that the unconfined compressive strength of solidified contaminated soil increases remarkably with the increase of curing time, and the strength at curing time of 28 d can be 2.4 times of that at curing time of 7 d. The strength of solidified soil decreases with the increasing concentration of chromium. When the dosage of CaSx is 0.1%, the strength of soft soil can increase 28% and reach 1.76 MPa. The chromium concentration in leachates becomes smaller after adding CaSx, and the concentration decreases with the increasing dosage of CaSx. Under the case of the chromium concentration as 15000 mg●kg-1, the chromium concentration in leachates is as small as 1.67 mg●L-1 when adding 0.3% CaSx to contaminated soft soil. The solidification/stability effect of soils can be improved obviously, and the solidification efficiency can reach 80.1%-98.9% when adding 0.3% CaSx to contaminated soft soil. |
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| 备注/Memo: | 收稿日期: 2020－08－17. 宁波大学学报（理工版）网址: http://journallg.nbu.edu.cn/ 基金项目: 国家自然科学基金（51678311）; 浙江省自然科学基金（LY19E080011）; 宁波市社发重大项目（2017C510002）. 宁波大学学报（理工版）网址：http://journallg.nbu.edu.cn/第一作者: 倪家琪（1996－）, 女, 浙江宁波人, 在读硕士研究生, 主要研究方向: 环境岩土工程. E-mail: 460890493@qq.com *通信作者: 王艳（1985－）, 女, 湖北随州人, 博士/副教授, 主要研究方向: 环境岩土工程. E-mail: wangyan@nbu.edu.cn |
