Electrokinetics Across Disciplines and Continents pp 143-159 | Cite as
Electrokinetic Remediation of Copper Mine Tailings: Evaluating Different Alternatives for the Electric Field
Abstract
Due to the magnitude of the mining activity in Chile, it becomes necessary to find solutions to mitigate the impact of mining waste on the environment. One method that could be suitable for remediation of mining wastes is the use of electric fields for the removal of metals, the so-called electrochemical remediation: electrokinetic or electrodialytic remediation (EKR or EDR). Especially, metals such as copper, zinc, lead, and arsenic have been removed or concentrated when applying electric fields—and these metals are typically also found in mining waste. The use of this remediation technology will imply the periodic application of the method in order to remove the additional soluble copper that will be generated with time. Therefore, the remediation action for this heterogeneous solid waste is to remove the soluble copper in the tailings and in this way making the final residue more stable.
In this work, an EKR cell for copper mine tailings using different types of electric fields was analyzed. The analysis includes: EKR with (a) direct current fields, (b) sinusoidal electric field obtained by applying simultaneously continuous-alternating voltages (at both high and low frequencies), and (c) pulsed electric fields.
According to the conditions studied in this investigation, the laboratory results showed that a high frequency sinusoidal electric field improves the EKR process, and increasing the effective voltage improves the remediation action, especially when a polarity inversion is present, which reduces polarization during the process.
Keywords
Direct current Pulsed electric fields Alternating current Sinusoidal electric fields Current reversal Copper removalReferences
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