Experimental study on remediation of petroleum-contaminated soil by combination of freeze-thaw and electro-osmosis

Suiqiao Yang; Hu Zhang; Yang Hu; Huijun Jin; Jintao Hu; Hongchun Li; Ming Lu

doi:10.1016/j.envpol.2023.121989

Experimental study on remediation of petroleum-contaminated soil by combination of freeze-thaw and electro-osmosis

Environ Pollut. 2023 Sep 15:333:121989. doi: 10.1016/j.envpol.2023.121989. Epub 2023 Jun 8.

Authors

Suiqiao Yang¹, Hu Zhang², Yang Hu³, Huijun Jin⁴, Jintao Hu¹, Hongchun Li¹, Ming Lu¹

Affiliations

¹ School of Civil Engineering, Northeast Forestry University, Harbin, Heilongjiang Province, 150040, China.
² School of Civil Engineering, Northeast Forestry University, Harbin, Heilongjiang Province, 150040, China; Permafrost Institute, Northeast Forestry University, Harbin, Heilongjiang Province, 150040, China; State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu Province, 730000, China. Electronic address: zhanghu@nefu.edu.cn.
³ Lanzhou University of Technology, Lanzhou, Gansu Province, 730050, China.
⁴ School of Civil Engineering, Northeast Forestry University, Harbin, Heilongjiang Province, 150040, China; Permafrost Institute, Northeast Forestry University, Harbin, Heilongjiang Province, 150040, China; State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu Province, 730000, China.

PMID: 37301452
DOI: 10.1016/j.envpol.2023.121989

Abstract

Electro-osmosis has been well recognized as a technique for the remediation of petroleum-contaminated soil, however seasonally freezing and thawing adds the complexity of petroleum mobility in cold regions. To investigate the influence of freeze-thaw on the electroosmotic removal of petroleum and explore the enhancement of freeze-thaw on the electroosmotic remediation efficiency in remediating the petroleum-contaminated soils, a set of laboratory tests were performed in three types of treatment modes, freeze-thaw (FT), electro-osmosis (EO) and freeze-thaw combined electro-osmosis (FE). The petroleum redistributions as well as the moisture content changes after the treatments were evaluated and compared. The petroleum removal rates of the three treatments were analyzed, and the underlying mechanisms were elaborated. The results indicated that the overall efficiency of the treatment mode regarding petroleum removal from soil followed the order of FE > EO > FT, corresponding to 54%, 36% and 21% in maximum, respectively. A considerable amount of water solution with surfactant was driven into contaminated soil during FT process, but the petroleum mobilization primarily occurred inside of the specimen. A higher remediation efficiency was yield in EO mode, but the induced dehydration and cracks leaded to the dramatical depression in the efficiency in further process. It is proposed that the petroleum removal is closely related to the flow of water solution with surfactant that is favorable to the solubility and mobilization of the petroleum in soil. Thus, the water migration induced by freeze-thaw cycles substantially improved the efficiency of the electroosmotic remediation in FE mode that gave the best performance for the remediation of the petroleum-contaminated soil.

Keywords: Cold regions; Electro-osmosis; Freeze-thaw cycles; Petroleum pollutants; Soil remediation; Water migration.

MeSH terms

Freezing
Osmosis
Petroleum* / metabolism
Soil
Soil Pollutants* / analysis
Surface-Active Agents
Water

Substances

Petroleum
Soil Pollutants
Water
Soil
Surface-Active Agents