Page 175 - 《精细化工》2020年 第10期

第 37 卷第 10 期 精 细 化 工 Vol.37, No.10
2020 年 10 月 FINE CHEMICALS Oct. 2020

水处理技术与环境保护
3 种固定剂联合修复铀尾矿污染土壤

周书葵，田林玉，荣丽杉，刘迎九，肖 江，李嘉丽

（南华大学 土木工程学院，湖南 衡阳 421001）

摘要：采用纳米沸石、磷酸二氢钾、改性生物炭联合对铀尾矿库中的核素铀进行化学固定，并利用毒性浸出实
验（TCLP）和 Tessier 逐级化学提取法，研究了固定前后铀的浸出特性与形态变化。TCLP 结果表明，添加不同
固定剂培养 30 d 后，与对照组相比，土壤中铀的浸出量减少了 42.13%~71.54%，且土壤 pH 与 TCLP 提取态铀
含量存在显著的负相关关系。Tessier 结果显示，施用不同固定剂后，土壤中可交换态和碳酸盐结合态铀质量分
数分别降低 7.38%~26.06%、1.43%~6.99%，而有机质结合态、铁锰氧化物结合态、残渣态铀比例分别增加 2.56%~
3.64%、2.71%~17.47%、4.07%~11.12%。在单一固定材料实验中，纳米沸石添加量为 6%（以土壤质量计，下同）
时稳定效果最佳，土壤可交换态铀比例降低 15.68%。在复配材料固定实验中，以 3 种固定剂按质量比 1∶1∶1，
总添加量为 6%时修复效果最好，土壤可交换态铀比例降低 26.06%。由此可见，3 种固定剂联合施用能有效降低
土壤中铀的活性，为其他放射性污染土壤修复提供理论参考。
关键词：纳米沸石；磷酸二氢钾；改性生物炭；铀尾矿库；化学固定；环境保护
中图分类号：X53 文献标识码：A 文章编号：1003-5214 (2020) 10-2105-07

Remediation of uranium contaminated soil with three combinated stabilizers

ZHOU Shukui, TIAN Linyu, RONG Lishan, LIU Yingjiu, XIAO Jiang, LI Jiali
（School of Civil Engineering, University of South China, Hengyang 421001, Hunan, China）

Abstract: The nuclide uranium in uranium tailings pond was chemically fixed by nanozeolite, potassium
dihydrogen phosphate and modified biochar. And the leaching characteristics and morphological changes of
uranium in soil before and after modification treatment were determined by toxicity characteristic leaching
procedure (TCLP) and Tessier stepwise chemical extraction. TCLP results showed that after 30 days of
solidification with different stabilizers, the amount of uranium leaching from soil decreased by 42.13%~
71.54% compared with that of the control group. Moreover, there was a significant negative correlation
between soil pH and TCLP-extracted uranium content. Tessier results showed that the mass fraction of
exchangeable and carbonate-bound uranium in soil decreased by 7.38%~26.06%, 1.43%~6.99% with
different fixatives, while the organic-bound, Fe-Mn oxide-bound and residual uranium increased by 2.56%~
3.64%, 2.71%~17.47%, 4.07%~11.12% respectively. In a single fixed material experiment, nano-zeolite
with 6% (based on the mass of soil, the same below) exhibited the best stability effect on the soil, the
proportion of exchangeable uranium in soil decreased by 15.68%. In the compound materials experiment,
the best repair effect was obtained by adding three stabilizers with a mass ratio of 1∶1∶1 and a total
dosage of 6%, the proportion of exchangeable uranium in soil decreased by 26.06%. Therefore, the
combined application of three stabilizers can effectively reduce the activity of uranium in soil, which
provides theoretical reference for the remediation of other radioactive contaminated soils.
Key words: nanozeolite; potassium dihydrogen phosphate; modified biochar; uranium tailings pond; chemical
immobilization; environmental protection

232
在核能生产及应用过程中产生了大量含有 238 U、 226 Ra、 Th 的废水、废石和尾矿等放射性废物，严

收稿日期：2020-04-24; 定用日期：2020-06-17; DOI: 10.13550/j.jxhg.20200350
基金项目：国家自然科学基金资助项目（51174117）；湖南省教育厅科研平台项目（15K106）；湖南省创新平台开放基金资助项目（17K078）
作者简介：周书葵（1965—），男，教授，E-mail：zhoushukui@usc.edu.cn。