A critical review of enhanced soil electrokinetics using perforated electrodes, pipes, and nozzles

Soil electrokinetic (SEK) is a remarkable technology that has applications in a variety of fields, such as polluted soil remediation, soil restoration, geophysics, dewatering, seed germination, pollution prevention, sedimentation, and consolidation. The current review is a continuation of our recently published series on process design modifications and material additives. There are three reviews have been recently published. The 1st and 2nd reviews were focused on SEK classification according to electrode position/types of contaminants movement (horizontal, vertical, and mixed horizontal and vertical) during (1993-2020) [1] and (2021-2022) [2], respectively. The 3rd review summarized the materials additives for enhancing the SEK intensification process during 2017-2020 [3]. Modifications were made to the shape of the electrodes to make research and operation more convenient and efficient. Based on exhaustive searches in six scientific search engines, we focused on the various roles of utilizing the perforated electrodes, pipes (a tubular section, or hollow cylinder, made of hard plastic), and nozzles (a tubular section, or hollow cylinder, made of flexible plastic) (PEPN) during SEK. The PEPN could perform SEK properly, remove nitrate, collect drainage water, reduce pH advection, enhance materials injection, distribute water throughout treated soil, incorporate a vacuum system, and monitor wells. Although the perforated electrodes may be considered an economic advantage due to the reduction of electrode surface area and, consequently, total costs, no comparative studies have been conducted to determine the effects of different electrode surface areas on the SEK efficiency, operation time, and energy consumption, which should be considered in future research.

Automated summary

Soil electrokinetic (SEK) is a significant technology with various applications in fields such as soil remediation, pollutant removal, and water regulation. This review summarizes the recent advancements in SEK, focusing on electrode modifications and material additives, and suggests future research directions.