At the heart of Metso is our drive to make the big difference to our customers. We offer equipment and services for the sustainable processing and flow of natural resources in the mining, aggregates, recycling equipment and process industries. Our customers are supported by a global network of over 14,000 professionals in more than 50 countries. Metso is listed on the Nasdaq Helsinki and had sales of about €3.2 billion in 2018.

Rodrigo Gouveia, VP, Tailings Management & Niclas Hällevall VP, Beneficiation Solutions, Metso
+358 20 484 100
Töölönlahdenkatu 2, FI-00100, Helsinki, Finland

New value-creation concept for the sustainable management of tailings

Metso has launched a new concept for the management of tailings. It enables the mines to process – and reprocess – their tailings in the most sustainable and economical manner possible.

In 2018, less than 5% of all tailings were dewatered in any way. This is an alarmingly low figure. We estimate that by 2025, the share of generated tailings that are dewatered will increase to 13%. Considering the recent dam failures and the increasing global need to use water more responsibly, not to mention the prerequisite for mines to keep their costs under control, we need a completely new agenda for tailings management.

Metso sees dry stacking of tailings as the most promising and sustainable way forward. Contrary to conventional belief, dry tailings can be CAPEX and OPEX efficient compared to wet or paste/thickened tailings. Technology is evolving and shifting the gears towards the adoption of smart and hybrid solutions that maximise ore and water recovery while optimising operational costs.

At the same time, the mining community needs to challenge its current way of thinking and include the reprocessing of tailings as part of the overall solution. A lot of old tailings facilities have residual mineral values, or secondary metals that could be exploited. Globally generated waste tailings are estimated to total ~3.2 billion tons for copper and ~1.8 billion tons for iron per annum. Extracting valuable minerals from the tailings and legacy dams is both responsible and a good opportunity to convert waste into value. The remaining dry waste can be used as backfill material in the mines.

Tailings management is not just a matter of finding the most technically suitable equipment or solution; it is about transformation and taking the end-of-mine strategy to a new level.

Metso estimates that, by 2025, the share of generated tailings that are dewatered will increase to 13% from just 5% in 2018
During testing, Metso’s VPX™ filter reached a water recovery rate of up to 90% and achieved a cake moisture content below 7%

Core component of future ready filtration solutions: Metso VPX™ Filter

To utilise the opportunities offered by the new tailings management concept, Metso can support the mines in designing and providing the optimal solution for each case with all the necessary products for the dewatering, handling and reprocessing of tailings.

Metso has been making filtration process equipment for more than 35 years. The now introduced concept takes tailings management to a new level, making full use of the extensive process and technology knowledge accumulated in the company. A core component of the new concept is the epochal Metso VPX™ Filter. The new filter has proven to be effective in filtering even the most difficult to dewater materials, while providing high water recovery and reuse. During testing, we have reached a water recovery rate of up to 90% and achieved a cake moisture content below 7%. The filter has a compact design and can handle basically any material with an operating pressure of up to 25 bars.

One of the unique features of the Metso VPX™ Filter is its sophisticated drive system. It is based on an electromechanical drive providing the fastest opening and closing time (also known as short technical time) of the top filters used in the mining industry. The cycle time and pressure can be easily adjusted to the ore being processed. Thanks to the modular design, the size of the filter can be increased just by adding sections of 60, 90, 120 plates, etc. to the filter. All parts are designed so that they fit into shipping containers allowing easy, risk-free transportation.

Test the concept at your mine

To help verify an individual mine’s business case, Metso can provide the mine site with a full-scale pilot unit, VPX10, for feasibility testing. The pilot unit is the most sophisticated in the market and can carry out high pressure dewatering, membrane pressing and air blow drying.

The VPX10 unit can be combined with Metso’s other pilot units, such as IPS thickeners and MHC™ hydrocyclones. It is equipped with a sophisticated control system and sensors that allow the use of remote services. With the help of the pilot unit and Metso’s expert and laboratory services, all kinds of material to be dewatered can be easily evaluated to build well-grounded business cases for mines to consider when making their future tailings management investments.

Read more about future ready tailings management solutions