Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8954724 | Journal of Environmental Management | 2018 | 10 Pages |
Abstract
Sulfate removal from mine or process water is a key issue in the mining industry. In this paper, precipitation with lime (calcium oxide) was integrated with electrocoagulation for sulfate removal from Pyhäsalmi/Finland mine water. Sulfate precipitation with calcium oxide decreased the sulfate concentration from 13,000â¯mg/L to 1600â¯mg/L. Various current densities were applied to the pre-treated mine water with various electrodes and aluminium and iron anodes. It was found that 25â¯mA/cm2 was the best tested current density for both anode types. At the second stage, this current density was used for different iron and aluminium anodes in various monopolar and bipolar configurations. It was found that this hybridisation is effective for sulfate removal, and that a bipolar configuration showed better results than the monopolar configuration. The best result was gained from 25â¯mA/cm2 with a two aluminium and two stainless steel anode-cathode configuration and calcium oxide pre-treatment to reach pH 12. The removal efficiency reached 84.4% and 63.8% with aluminium anodes in bipolar and monopolar configurations, respectively. This setup was able to decrease sulfate concentrations from 13,000â¯mg/L to 250â¯mg/L, which meets mine water discharge limits. Kinetic studies showed that iron and aluminium anodes obey pseudo-second order kinetic. Finally, the energy consumption was calculated.
Keywords
Related Topics
Physical Sciences and Engineering
Energy
Renewable Energy, Sustainability and the Environment
Authors
Elham Nariyan, Christian Wolkersdorfer, Mika Sillanpää,