Rapid solidification of Sr-contaminated soil by consecutive microwave sintering: mechanism and stability evaluation

Hexi Tang; Xiaoyan Shu; Wenxiao Huang; Yulong Miao; Minghe Shi; Shunzhang Chen; Bingsheng Li; Fen Luo; Yi Xie; Dadong Shao; Xirui Lu

doi:10.1016/j.jhazmat.2020.124761

Rapid solidification of Sr-contaminated soil by consecutive microwave sintering: mechanism and stability evaluation

J Hazard Mater. 2021 Apr 5:407:124761. doi: 10.1016/j.jhazmat.2020.124761. Epub 2020 Dec 9.

Authors

Hexi Tang¹, Xiaoyan Shu², Wenxiao Huang³, Yulong Miao⁴, Minghe Shi⁴, Shunzhang Chen⁵, Bingsheng Li⁶, Fen Luo², Yi Xie⁷, Dadong Shao⁸, Xirui Lu⁹

Affiliations

¹ State Key Laboratory of Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, PR China; Sichuan Radiation Detection & Protection Institute of Nuclear Industry, Chengdu 610052, PR China.
² National Co-Innovation Center for Nuclear Waste Disposal and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, PR China; Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, PR China.
³ Guangdong Provincial Key Laboratory of Radioactive and Rare Resource Utilization, Shaoguan 512026, PR China.
⁴ Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, PR China.
⁵ Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, PR China.
⁶ State Key Laboratory of Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, PR China; National Co-Innovation Center for Nuclear Waste Disposal and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, PR China.
⁷ University of Science and Technology of China, Hefei 230026, PR China; Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, PR China.
⁸ Nanjing University of Science and Technology, Nanjing 210094, PR China.
⁹ State Key Laboratory of Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, PR China; National Co-Innovation Center for Nuclear Waste Disposal and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, PR China; Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, PR China. Electronic address: luxiruimvp116@163.com.

PMID: 33316687
DOI: 10.1016/j.jhazmat.2020.124761

Abstract

Consecutive microwave sintering is a method proposed in this study to dispose soil contaminated by Sr during a nuclear accident by rapidly solidifying the contaminated soil. The results show that soil contaminated with 20 wt% SrSO₄ and 30 wt% SrSO₄ can be completely solidified by microwave sintering at 1100-1200 and 1300 ℃, respectively, for 30 min. Sr was found to be cured into slawsonite (SrAl₂Si₂O₈) and glass structures. Moreover, soil sintered at 1300 ℃ has large cured solubility (30 wt.%), good uniformity, and excellent hardness (6.9-7.2 GPa) and chemical durability (below 1.46 × 10^-5 g m^-2 d^-1 at 28 d). Thus, consecutive microwave sintering technology may provide a new method for treating Sr-contaminated soil in case of a nuclear accident emergency.

Keywords: Chemical durability; Consecutive microwave sintering; Glass-ceramic; Slawsonite; Sr-contaminated soil.

Publication types

Research Support, Non-U.S. Gov't