Closed-loop water management for mining operations — recovering thickener overflow and process water for reuse, cutting freshwater draw by up to 90% and moving sites toward zero liquid discharge.
Turning waste streams into the largest water source on site
Water is one of the most contested resources in mining, and recycling it is both an environmental obligation and a powerful economic lever. A well-designed closed-loop circuit recovers thickener and clarifier overflow, reclaims water from tailings thickening and dewatering, and treats it back to a quality fit for crushing, grinding, flotation, dust suppression or discharge. Modern operations routinely recycle 70–90% of their water demand, slashing freshwater abstraction, reducing the size and cost of discharge treatment, and shrinking the footprint of tailings storage. Achieving this reliably depends on a clear site-wide water balance — mapping every inflow, loss and reuse point — and on treatment robust enough to manage the salinity, scaling species and reagent residues that concentrate as water is cycled. Reynolds & Bauhm engineer these circuits for the abrasion, remote-site and seasonal-variability conditions that define mineral processing, integrating thickening, clarification, filtration and, where required, desalination or zero-liquid-discharge polishing.
Where the water comes from and how it is returned to service
High-rate and paste thickeners return clarified overflow directly to process while concentrating underflow to 55–80% solids — the single largest source of recovered water on most sites.
Lamella clarifiers, DAF and media or self-cleaning filters reduce suspended solids and residual metals to a quality compatible with flotation chemistry and reuse without scaling downstream circuits.
A dynamic site water balance reconciles rainfall, evaporation, entrainment and reuse, sizing storage and buffer ponds so the circuit stays stable through wet and dry seasons.
Where salinity builds up, brackish RO and evaporation/crystallisation bleed and recover the concentrate, approaching zero liquid discharge and protecting receiving environments.
Why it pays: recycling 80–90% of process water typically cuts freshwater purchase and abstraction-licence costs, reduces discharge-treatment duty, and lowers the volume of free water reporting to tailings — improving dam stability and closure outcomes.
Explore the connected stages
Thickening and dewatering that recover water and stabilise tailings for safe storage.
Explore Mining TailingsClarification and filtration of crushing, grinding and flotation circuit water for reuse.
Explore Process WaterNeutralisation and metal precipitation so impacted water can re-enter the circuit.
Explore AMD TreatmentThe full mining water-treatment overview — tailings, process water, dewatering and compliance.
Mining OverviewWe model the water balance and design the thickening, clarification and polishing that make high recovery reliable.
Our expertise spans multiple industries with sector-specific water treatment solutions.