Title |
Novel Two-stage Biochemical Process for Hybrid Passive/Active Treatment of Mine-influenced Water |
ID_Doc |
23973 |
Authors |
Lundquist, L; Baldwin, SA |
Title |
Novel Two-stage Biochemical Process for Hybrid Passive/Active Treatment of Mine-influenced Water |
Year |
2022 |
Published |
Mine Water And The Environment, 41, 1 |
DOI |
10.1007/s10230-021-00843-6 |
Abstract |
Current passive treatment systems for metal removal from sulphate-rich mine-influenced water, such as biochemical reactors and permeable reactive barriers, are based on a one-time application of a solid waste organic matrix. These are prone to declining efficiency and reliability as the carbon source is depleted over time. Also, in many of these systems, metal sulphide precipitates are retained in situ, creating a legacy liability on the mine site. A novel hybrid passive/active treatment system was designed to overcome these shortcomings by supplying a liquid nutrient source derived in a separate upstream step through fermentation of waste organic material, and by carrying out sulphidogenesis and chemical metal precipitation in two separate packed-bed column reactors, in which sulphide is fed back from the bioreactor into the upstream metal sulphide precipitation reactor. A separate metal precipitation module will enable eventual removal of the metals from the mine site. Liquid fermentation products from a woodchip/hay-grass mixture were compared with molasses as nutrient sources. The systems were tested for a duration of 96 days, demonstrating that the tested liquid carbon sources reduced sulphate at maximum rates of 41.2 and 28.7 mg-SO42-L-1 d(-1), respectively, and removed 85% and 90% Zn, respectively, in the chemical precipitation step, making it possible to remove these from the mine site for recycling. |
Author Keywords |
Zinc; Sulphate; Sulphate reducing bacteria; Metals; Circular economy |
Index Keywords |
Index Keywords |
Document Type |
Other |
Open Access |
Open Access |
Source |
Science Citation Index Expanded (SCI-EXPANDED) |
EID |
WOS:000724620900001 |
WoS Category |
Water Resources |
Research Area |
Water Resources |
PDF |
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