Application of Decanting Centrifuges in the Mining Industry

Application of High-Speed Decanting Centrifuges in the Mining Industry

With its core advantages of continuous operation, high automation and high solid-phase recovery rate, the High-Speed Decanting Centrifuge plays a critical role in such processes as solid-liquid separation, tailings treatment and mineral processing & purification in the mining industry. It is one of the core pieces of equipment for achieving cleaner production and efficient resource utilization in mines.

I. Core Application Scenarios

1. Tailings Dry Stacking and Resource Utilization

Tailings are the waste generated after mining and mineral processing operations. The traditional storage method poses risks including large land occupation, groundwater pollution and high susceptibility to debris flows. The decanting centrifuge can perform efficient solid-liquid separation of tailings slurry:

The moisture content of the separated solid phase can be reduced to 15%–25%, meeting the requirements for dry stacking or resource utilization such as brick-making and pavement construction.

The liquid phase can be recycled for mineral processing processes, significantly reducing fresh water consumption and complying with the policy requirements of water conservation and emission reduction in mines.

This scenario is particularly suitable for tailings treatment in metal mines (iron ore, copper ore, gold ore) and non-metallic mines (coal mine, sand and gravel mine).

2. Solid-Liquid Separation in Mineral Processing

A large volume of slurry containing slime is generated in mineral processing processes such as flotation and magnetic separation. The decanting centrifuge functions in two aspects:

Slurry Concentration: Concentrate low-concentration slurry to high concentration, improving the processing efficiency of subsequent mineral processing equipment.

Fine-Grained Mineral Recovery: Recover the lost fine-grained valuable minerals (e.g., fine particles of gold, silver and copper) in the slurry, increasing the resource recovery rate of mines.

3. Mine Wastewater Treatment

Mine wastewater includes mineral processing wastewater, mine inflow water and ore washing wastewater, etc., featuring complex water quality with high levels of suspended solids, heavy metal ions and mineral processing reagents. The decanting centrifuge can achieve the following:

Remove suspended solids (SS) in wastewater and reduce wastewater turbidity.

Cooperate with chemical precipitation processes to separate heavy metal hydroxide precipitates, enabling the treated wastewater to meet reuse or discharge standards.

4. Coal Slime Dewatering (Exclusive to Coal Mining Sector)

Coal slime generated during coal mining and washing processes has fine particle size and high moisture content, and its direct discharge is likely to cause environmental pollution. The decanting centrifuge can reduce the moisture content of coal slime to 20%–30%. The dewatered coal slime can be sold as fuel, realizing the resource utilization of coal slime.

II. Core Advantages of Application in the Mining Industry

1. Adaptability to Harsh Working Conditions

Mine slurry is characterized by high concentration, high abrasiveness and large fluctuations in solid content. The key components of the decanting centrifuge, such as the bowl and scroll, can be made of wear-resistant alloys (e.g., duplex stainless steel, cemented carbide), which can withstand the abrasion of hard particles in the slurry and have a long service life.

2. Continuous and Automated Operation

The equipment can achieve 24-hour continuous feeding, separation and discharge without frequent shutdowns for cleaning. Equipped with a PLC control system, it can automatically adjust parameters such as rotational speed and differential speed to adapt to fluctuations in slurry concentration, reducing manual intervention and lowering mine operation costs.

3. Small Floor Space Requirement

Compared with traditional equipment such as plate-and-frame filter presses and belt filter presses, the decanting centrifuge has a compact structure, with a floor space only 1/3–1/2 that of filter presses with the same processing capacity, making it suitable for mine working conditions with limited space.

III. Selection and Usage Precautions

1. Key Parameter Matching

Processing Capacity: Select the model according to the hourly flow rate of mine slurry to ensure the equipment operates under rated working conditions.

G-Force: The solid-phase particles of mine slurry are fine, so models with high G-force (≥2000G) should be selected to improve the sedimentation and separation efficiency of fine particles.

Wear Resistance: Priority should be given to models whose bowls and scroll blades are treated with tungsten carbide spraying or wear-resistant surfacing to cope with the abrasiveness of the slurry.

2. Auxiliary System Configuration

Equip a feed buffer tank to stabilize the concentration and flow rate of slurry feed and avoid equipment overload.

Install online monitoring instruments for solid-liquid separation to monitor the separation effect in real time and facilitate timely adjustment of operating parameters.

3. Environmental Compliance Requirements

Mine applications must comply with local environmental protection policies, with a focus on the disposal path of the dewatered solid phase (whether it meets solid waste standards) and the liquid phase reuse rate (which must meet the water quality indicators for mineral processing).

IV. Application Trends

With the accelerated green and intelligent transformation of the mining industry, the application of decanting centrifuges presents two major trends:

Intelligent Upgrading: Equipped with Internet of Things (IoT) technology to realize remote monitoring, fault early warning and intelligent operation and maintenance.

Modular Integration: Integrated with flocculant dosing systems and sludge conveying systems to form integrated tailings treatment equipment, reducing the difficulty of on-site installation and commissioning in mines.