Coupled with EDDS and approaching anode technique enhanced electrokinetic remediation removal heavy metal from sludge

In this work, the novel technology was used to remove heavy metal from sludge. The coupled with biodegradable ethylenediamine disuccinic acid (EDDS) and approaching anode electrokinetic (AA-EK) technique was used to enhance heavy metal removing from sludge. Electric current, sludge and electrolyte characteristics, heavy metal removal efficiency and residual content distribution, and heavy metal fractions percentage of variation were evaluated during the electrokinetic remediation process. Results demonstrated that the coupled with EDDS and AA-EK technique obtain a predominant heavy metal removal efficiency, and promote electric current increasing during the enhanced electrokinetic remediation process. The catholyte electrical conductivity was higher than the anolyte, and electrical conductivity of near the cathode sludge achieved a higher value than anode sludge during the coupled with EDDS and AA-EK remediation process. AA-EK technique can produce a great number of Hthorn, which caused the sludge acidification and pH decrease. Cu, Zn, Cr, Pb, Ni and Mn obtain the highest extraction efficiency after the coupled with EDDS and AA-EK remediation, which were 52.2 +/- 2.57%, 56.8 +/- 3.62%, 60.4 +/- 3.62%, 47.2 +/- 2.35%, 53.0 +/- 3.48%, 54.2 +/- 3.43%, respectively. Also, heavy metal fractions analysis demonstrated that the oxidizable fraction percentage decreased slowly after the coupled with EDDS and AA-EK remediation. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a novel technology was applied to remove heavy metals from sludge, with the coupled EDDS and AA-EK technique showing enhanced efficiency. The results indicated that the technique led to increased electric current and predominant heavy metal removal, demonstrating its effectiveness in electrokinetic remediation.