Electrokinetic Remediation of Zinc and Copper Contaminated Soil: A Simulation-based Study

Abstract

Electrokinetic is an effective and innovative method to remediate different kinds of soils, especially low permeable finedgrain soils such as silty and clayey soils. In this method, by applying a direct-current electric field into a contaminated soil resulted in different transport phenomena, the soil is remediated. This paper's objective is to propose a numerical model for Electrokinetic remediation of zinc and copper contaminated soils. Different transport phenomena including ion migration, electroosmosis flow, and diffusion were taken into account in the model. Chemical reactions such as precipitation/dissolution, adsorption onto the soil surface, and water chemical equilibrium were considered as well. Furthermore, instead of simplified boundary conditions (Neumann or Dirichlet) that cannot properly reflect the reality of the Electrokinetic remediation process, the realistic boundary conditions were used with consideration of flux and electrolysis reaction at the electrodes. The simulation results compared with the available experimental data in the literature. The coefficient of determination and the index of agreement indicated that the present model is consistent with the tests' results. Thus, the assumptions considered in the present study are acceptable.

Mathematical Modeling and Sensitivity Analysis on Cadmium Transport in Kaolinite under Direct Current Electric Field

“…Asadollahfardi et al proposed an explicit finite difference model to simulate lead removal from kaolinite clay under EKR process and their simulation results were consistent with the experimental data [19]. Rezaee et al presented a model to simulate remediation of zinc and copper contaminated soils under EKR process considering different chemical reactions and they reported that their model was capable of simulating the remediation process [20]. This paper presents a numerical model based on Crank-Nicolson method to simulate the EKR of a cadmiumcontaminated kaolinite under an acid-enhanced condition.…”

“…The electric field was set constant with time [15,16,19,20]; therefore, the transport equation for each chemical species along with appropriate boundary conditions at the electrodes for each ion is presented. Cadmium:…”

“…The transport equation for each ion should be solved by using appropriate initial condition, and the chemical reactions should be satisfied at each time step, then equilibrium concentration of each chemical species goes to transport formulation to obtain the concentrations at the next time step. The finite difference formulation which was used to solve the transport equation is completely described in [20]. The electroosmotic permeability in soils is in the range of 10 -5 to 10 -4 cm 2 s -1 V -1 [22].…”

Leaching of Polar Herbicides in the Presence of Designed Carbon Sorbents in Soil

“…There are several techniques that have been used for stabilization of pollutants in the soil environment including electrokinetic (Rezaee, Ghomesheh, and Hosseini 2017), encapsulation (Shen et al 2019), and application of sorbents such as organophilic clays, ferrous sulfate, and carbon sorbents (Zhang et al 2010;Shen et al 2019). Biochar is a carbonaceous sorbent derived from biomass pyrolysis under limited supply of O 2 and at temperatures of less than 700°C (Lehmann and Joseph 2015).…”

Bioaugmentation of Vibrio alginolyticus in phytoremediation of aluminium-contaminated soil using Scirpus grossus and Thypa angustifolia

“…The pollution of soil requires human intervention with the existing technology to overcome pollution ( Imron et al., 2020 ; Menon et al., 2019 ). Efforts were initiated to process Al-contaminated soils by using several methods, namely, precipitation ( Kurniawan et al., 2018 ), evaporation, ion exchange and electrolysis ( Manikandan et al., 2020 ; Rezaee et al., 2017b , 2017a ). However, some of the above-mentioned technologies have caused further issues from the chemical residue and the used energy.…”