Treatment method | Suitable for removing | Advantages | Disadvantages | Reference |
Aeration | Fe2+ and Mn | Low operation cost, releases CO2 from mine water, increases DO | Not effective for water with low Fe2+ content | [19] |
High-density sludge process | Fe2+, Fe3+, Al, Mn, Cu, Zn, Pb and | Generation of low volumes of sludge, high water recovery, low lime cost, scaling control, can treat large flows of AMD, sludge recycling | Limited sulfate removal, generation of sludge | [10] |
Limestone/lime neutralization | Fe and Al | Low alkali cost, sludge recycling | Limited sulfate removal, generation of sludge | [20] |
Membrane filtration | Brackish and saline mine water | Good quality of treated water, high water recovery | Scaling, fouling, needs pretreatment and post-treatment, sludge and brine production and short membrane life | [21] |
Biological sulfate removal | Sulfate and Fe | Very effective in removing sulfates | Best for water with pH > 5, effluent metal concentration may exceed permissible limits | [22] |