Electrokinetic treatments of soils: potential for geoenergy applications

Northwestern University, Department of Civil and Environmental Engineering, Mechanics and Energy Laboratory 2145 Sheridan Road, Evanston, Illinois 60208 United States of America

^* Corresponding author: af-rottaloria@northwestern.edu

Abstract

The application of a direct current electric field to porous materials such as soils in the form of an electrokinetic treatment induces a variety of multiphysical phenomena. Critical phenomena involved during an electrokinetic treatment of soils are electrical migration (i.e., movement of ions), electroosmosis (i.e., movement of water), electrolysis (i.e., breakdown of chemical compounds), and electrochemical reactions (i.e., oxidation/reduction and precipitation/mineralization reactions). Such phenomena lead to changes in the structure of soils. As changes in the structure of soils induce variations in their properties and behaviors (e.g., thermo-hydro-mechanical), electrokinetic treatments represent resourceful means to address broad geoengineering challenges. The purpose of this paper is to highlight the potential of electrokinetic treatments as versatile techniques capable of providing solutions for diverse geoengineering applications via a controllable change of the properties and behaviors of soils. From this perspective, this work specifically encompasses electrokinetically induced phenomena in soils and expands on opportunities in the context of geoenergy applications, among others, which can be mediated by electrokinetic treatments.