Solids Handling Pumps for Thickened Tailings Transfer in the Process of Mine Backfilling

Updated: Jan 10

Background information

Our customer is a large underground mining producer of precious metal, specialising in high grade silver and gold deposits. The company has a solid asset base, a large portfolio of projects in development and a clear strategy.

Currently, it operates three underground mines. All underground mining activities are epithermal deposits and the main extraction method used is cut-and-fill mining. The mineral extracted is processed and transformed into a silver and gold concentrate.

The product

The process of metal extraction is accompanied by the accumulation of large quantities of tailings that are sometimes used for refilling pits which are no longer in use.

With increasing environmental awareness, the handling of tailings from mining processes has become a crucial issue for all mining companies. Given that they are a by-product of the mineral concentration process, tailings do not have any real economic value. They are toxic and generally comprise residues of minerals, soil, water and chemical components from the process itself. Consequently, the disposal of tailings represents a real problem in the mining industry due to increasing volumes, the need for large storage space, the risk of failure of retention basins as well as the water contained in tailings whose infiltrations can harm the environment. The application

In this context, the alternative of backfilling the mine appears to be a reasonable solution for the costs, the risks and the problems related to the handling of tailings.

Thickened tailings for mine backfilling.

This solution requires a lower capital expenditure as well as lower operating costs and reduces the environmental impact significantly.

The reduction of water consumption in the treatment process leads to the formation of a more viscous (paste-like) product, which reduces the risk of contaminated water infiltration significantly.

In this case, the product is stored in underground locations that have already been utilised. This process is called pit backfilling.

To carry out the backfilling process, the pulp must go through a concentration process in which its liquid is separated from the solids with the objective to increase the solid content and make the material more suitable for pit backfilling.

It is here that ABEL solids handling pumps come into play and become a well-suited solution for thickened tailings handling in the process of backfilling.

Thickened tailings transferred with an ABEL SH pump.

The solution

When it comes to working under the requirements of mining applications, the equipment installed must guarantee a high degree of reliability and availability and it must also be suited for operation in challenging conditions and during long periods without interruptions.

ABEL SH pumps for solids handling with a flow rate of 95 m3/h, a pressure of 100 bar and a power of 680 kW per unit.

ABEL SH solids handling pumps represent the solution for very challenging work conditions.

These units are based on piston pump technology and consist of the following 3 main components: the pump, the hydraulic drive unit and the control unit with PLC.

Main characteristics

Performance range: up to 300 m³/h (880 GPM); up to 16.0 MPa (2320 psi)

Paste-like slurry transferred with ABEL SH pumps.


  • Transfer of media with solid content of up to 80%

  • Extra-large suction valves with a high degree of volumetric efficiency.

  • Hydraulic cone valves preventing undesired product backflow.

  • Cone valves with long stems ensure a safe separation between the product and the hydraulic side.

  • Strokes per minute are low and ensure a low mechanic wear.

  • Possibility of installing a feed screw system to improve the volumetric efficiency of filling.

Thanks to these advantages and design, ABEL SH pumps offer a long and useful life that satisfy the tough requirements and demands of the mining industry.

The pressure ranges covered by the SH series solids handling pumps allow them to handle long pumping distances, making them well suited for pit backfilling.

ABEL has a distribution partnership with IndustriTech Pty Ltd for the Australian mining market.

IndustriTech provides service-oriented solutions in three areas: technical advice, reliability and repair services and distribution services. Together with ABEL’s wide range of positive displacement pumps, it will provide complete customised product and service solutions for high solids concentrations and efficient dewatering processes. Typical applications are dewatering, tailings, solid transfer and thickener underflow.

For over 70 years, ABEL has specialised in pumps for filter press feeding and filter cloth cleaning. Both ABEL’s piston diaphragm and high-pressure plunger pumps provide tailor-made features to ensure a short, efficient and energy saving filter press process. This performance can be seen in the high level of dryness of the filter cake, resulting in increased daily metal extraction and profitability for the customer.