A decant pump is a specialized pumping system used in mining operations to remove water that has accumulated on the surface of a tailings storage facility (TSF), residue storage area, or mine water impoundment, enabling recovery of that water for reuse in the processing plant or controlled discharge. In bauxite residue management, decant pumps are used to transfer highly caustic decant water from the residue storage facility back to the alumina refinery for reuse as process water, minimizing both water consumption and the environmental footprint of the disposal operation. Gold mining tailings facilities deploy decant pumps to reclaim process water from the TSF decant pond, reducing the demand for fresh make-up water and minimizing the volume of potentially cyanide-bearing water that requires treatment. Iron ore tailings operations use large-capacity decant pumps, often submersible or pontoon-mounted floating pump systems, to remove water from the decant pond and return it to the concentrator plant or thickeners for reuse. In diamond mining, decant pumps recover water from kimberlite tailings ponds and return it to the plant for recirculation through DMS and other processing circuits. Decant pumps must be designed to handle the specific chemical properties of the decant water, including pH, total dissolved solids, and abrasiveness, and must be positioned to minimize the intake of suspended tailings solids that could cause pump wear and damage. Pontoon-mounted floating decant pumps are commonly used to accommodate the changing water levels within TSFs.
