How to tackle the stringent sulfate removal requirements in mine water treatment : a review of potential methods
Runtti, Hanna; Tolonen, Emma-Tuulia; Tuomikoski, Sari; Luukkonen, Tero; Lassi, Ulla (2018-07-10)
Hanna Runtti, Emma-Tuulia Tolonen, Sari Tuomikoski, Tero Luukkonen, Ulla Lassi, How to tackle the stringent sulfate removal requirements in mine water treatment—A review of potential methods, Environmental Research, Volume 167, 2018, Pages 207-222, ISSN 0013-9351, https://doi.org/10.1016/j.envres.2018.07.018.
© 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
https://creativecommons.org/licenses/by-nc-nd/4.0/
https://urn.fi/URN:NBN:fi-fe2018112248836
Tiivistelmä
Abstract
Sulfate (SO₄²⁻) is a ubiquitous anion in natural waters. It is not considered toxic, but it may be detrimental to freshwater species at elevated concentrations. Mining activities are one significant source of anthropogenic sulfate into natural waters, mainly due to the exposure of sulfide mineral ores to weathering. There are several strategies for mitigating sulfate release, starting from preventing sulfate formation in the first place and ending at several end-of-pipe treatment options. Currently, the most widely used sulfate-removal process is precipitation as gypsum (CaSO₄·2H₂O). However, the lowest reachable concentration is theoretically 1500 mg L⁻¹ SO₄²⁻ due to gypsum’s solubility. At the same time, several mines worldwide have significantly more stringent sulfate discharge limits. The purpose of this review is to examine the process options to reach low sulfate levels (< 1500 mg L⁻¹) in mine effluents. Examples of such processes include alternative chemical precipitation methods, membrane technology, biological treatment, ion exchange, and adsorption. In addition, aqueous chemistry and current effluent standards concerning sulfate together with concentrate treatment and sulfur recovery are discussed.
Kokoelmat
- Avoin saatavuus [34939]