Evaluating iron remediation with limestone using spectral induced polarization and microscopic techniques

Na Hao; Jianshe Ye; Li Zhao; Meng Sun; Yuqing You; Chi Zhang; Junnan Cao; Yu Peng; Shuai Zhang; Liang-Tong Zhan; Yunmin Chen; Bate Bate

doi:10.1016/j.scitotenv.2021.149641

Evaluating iron remediation with limestone using spectral induced polarization and microscopic techniques

Sci Total Environ. 2021 Dec 15:800:149641. doi: 10.1016/j.scitotenv.2021.149641. Epub 2021 Aug 13.

Authors

Na Hao¹, Jianshe Ye², Li Zhao³, Meng Sun⁴, Yuqing You⁵, Chi Zhang⁶, Junnan Cao⁷, Yu Peng⁸, Shuai Zhang⁹, Liang-Tong Zhan¹⁰, Yunmin Chen¹¹, Bate Bate¹²

Affiliations

¹ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: nahao@zju.edu.cn.
² MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: 21812138@zju.edu.cn.
³ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: 17099440712@163.com.
⁴ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: 21912205@zju.edu.cn.
⁵ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: 2522645961@qq.com.
⁶ Institut für Meteorologie und Geophysik (IMGW), University of Vienna, Vienna, Austria; Department of Geology, University of Kansas, Lawrence, KS 66045, USA. Electronic address: chizhang@ku.edu.
⁷ Department of Civil Engineering and Construction, Georgia Southern University, 1332 Southern Drive, Statesboro, GA 30458, USA. Electronic address: jcg83@mst.edu.
⁸ College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: zjupengyu@zju.edu.cn.
⁹ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: zhangshuaiqj@zju.edu.cn.
¹⁰ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: zhanlt@zju.edu.cn.
¹¹ MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: chenyunmin@zju.edu.cn.
¹² MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China. Electronic address: batebate@zju.edu.cn.

PMID: 34426370
DOI: 10.1016/j.scitotenv.2021.149641

Abstract

Groundwater contamination with iron caused by mining and landfill activities has fueled the development of remediation strategies. Permeable reactive barriers (PRBs) are commonly applied in subsurface remediation because of their high removal effect and low costs. Spectral induced polarization (SIP) technique has been approved for its nondestructive ability to monitor the geochemical processes in porous media. In this study, SIP technique was applied for monitoring iron remediation by limestone at column scale. The chemical analysis showed the pH of the porous fluid increased - attributed to the dissolution of limestone, which promoted the precipitation of iron. The precipitate phases included both γ-FeOOH and Fe₂O₃ based on X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) results. The micro computed tomography (CT) technique investigated the uneven distribution of the precipitates in the column, which indicated the existence of preferential flow. SIP signals revealed the quantity of the accumulated iron precipitates, which was proved by the chemical measurement and calculation. SIP signals also derived the time evolution of both the average precipitate size and size distribution, which elucidated the processes of precipitate crystal growth and aggregation during Fe flow-through. Above results suggest that SIP holds the promise of monitoring the engineering barrier performance.

Keywords: Iron; Limestone; Precipitation; Remediation; Spectral induced polarization.

MeSH terms

Calcium Carbonate
Groundwater*
Iron
Water Pollutants, Chemical* / analysis
X-Ray Microtomography

Substances

Water Pollutants, Chemical
Iron
Calcium Carbonate