Application of Sand Dewatering Screens in Ore Processing

Application of Sand Dewatering Screens in Ore Processing

Dewatering screens play a vital role in mineral processing circuits, serving as a critical solid-liquid separation device that removes excess water from ore slurries, improves product quality, and enables water recycling throughout the plant.

Key Applications in Ore Processing

1. Tailings Sand Recovery and Dewatering
Dewatering screens are extensively used to recover tailings sand from ore treatment plants. Real production results have demonstrated that a single Linatex vibrating-dewatering screen can recover more than 150,000 tons of tailings sand annually, delivering significant economic and environmental benefits. This application is particularly valuable in iron ore, coal, and mineral sands operations where fine material recovery directly impacts profitability.

2. Post-Beneficiation Dewatering
In circuits involving classification, flotation, spirals, magnetic separation, or other beneficiation stages, dewatering screens are positioned to produce a cleaner, more conveyable product while maximizing water return to the process. The FLS VSW Series, for example, serves as the primary moisture-control solution for tailings or middling streams, easing the load on downstream thickeners and filters while improving circuit water balance.

3. Fine Coal and Mineral Dewatering
Dewatering screens are widely applied to coal and mineral fines, with vibrating screens proven to be an economical means for a multitude of dewatering applications ranging from aggregates to coal to food. Screen openings for fine coal dewatering typically range from 0.25 mm to 0.5 mm, and cross dams are often used to periodically disturb the bed and promote free drainage of water.

4. Gold Circuit Applications
In gold processing circuits, dewatering screens serve multiple functions. UHS Series horizontal screens prevent carbon carryover that would impact recovery and cause downstream issues, safeguarding recirculation systems and maintaining clean feed to sensitive equipment. Additionally, dewatering screens handle precious metals ore as part of their wide application range, producing consistent drip-free product suitable for downstream processing.

5. Desliming and Degritting
Dewatering screens have a wide variety of applications including dewatering, desliming, degritting, rinsing, scrubbing, sizing and washing. They handle materials such as sand, gravel, crushed aggregates, frac sand, industrial sands, mineral sands, hard rock, precious metals ore, coal, iron ore, salt and other granular materials.

Technical Capabilities

Dewatering screens can achieve surface moisture as low as 7%, though final moisture depends on surface area, surface morphology and contact angle. Finer materials (100% passing 150 µm) typically dewater to a drip-free consistency with surface moisture content that may exceed 20%. The steep, downward-inclined feed section achieves rapid drainage, while the slightly upward-inclined discharge section creates a deep bed that acts as a filter medium, allowing retention of material much finer than the screen openings.

Economic and Environmental Benefits

Dewatering screens generally have lower energy consumption compared to other equipment like filter presses and centrifuges, contributing to reduced production costs. By promoting water recycling and decreasing the volume of wastewater requiring treatment, they also minimize the environmental footprint of mineral processing operations.

For inquiries about specific dewatering screen models and their application to your ore processing circuit, please contact our technical sales team.