Engineering solutions provider Weir Minerals Africa has evolved its homegrown innovations to fit any dewatering requirements worldwide.

Backed by strong development expertise, significant capital injection, continuous product improvement and a sharp focus on integrated solutions, the company now has a product range that covers end-to-end solutions for dewatering challenges, including specialised, custom-built pontoons.

Dewatering can be an expensive and complex challenge, however, the removal of excess water from working areas is integral to allowing continuous safe and productive excavation operations, says Weir Minerals Africa slurry pumps product manager Marnus Koorts.

The challenges operators face with water differ from region to region and a number of factors can affect the dewatering system, such as the permeability and porosity of the ground, the amount of surface water and geological features such as seasonal rainfall, besides others.

However, they all require effective water management systems and the nature of dewatering applications has increased demand for engineered dewatering solutions, he tells Engineering News.

Further, it is increasingly important to seek out different methods to improve this process.

“Dewatering is a science on its own, which is why Weir Minerals [aims to] deliver bespoke, comprehensive, reliable and flexible strategies that are cost effective and manageable.”

Underground mining conditions can be improved owing to decreased water and slimes handling, while there is increased scrutiny and pressure to improve the management of tailings.

Designed at the company’s Isando, Johannesburg offices, the pontoon and barge designs are now used across the world, at more than 100 sites, with Weir Minerals globally equipped with the in-house capabilities to build and deploy the solutions.

The pontoon design, a relatively new concept in the market, allows Weir Minerals’ equipment to float out over water bodies, such as tailings dams, for easier access.

These floating pumpstations are designed to accommodate the entire Weir Minerals dewatering product range, including valves, floating hoses, end suction centrifugal pumps, horizontal split case pumps and vertical turbine pumps.

Mounting equipment on a floating structure also plays a significant role in reducing the total cost of ownership for mines and other industries.

With standardised components to improve speed to market and reaction times, Weir Minerals is able to complete a typical detailed custom design, procurement, manufacture and assembly in as little as two weeks.

Besides the structure and the attached pump, Weir Minerals manufactures most of the on-board equipment and related components in-house, with additional custom work including electronics, electrical and cabling.

“It is specialised in the way it is applied,” he says, noting the diverse designs for different operations.

Each pontoon is designed with a fully tested anchoring system and can be customised for extreme weather conditions or even, in some cases, acid-proofed.

One project required the pontoon and walkways to be “alligator-proofed”.

“We get very specific requests,” Koorts says, highlighting requirements such as height restrictions, with hydraulic lifting capabilities during maintenance, and floating or fixed walkways.

The group also designed a pontoon with a 1.5 MW motor installed on it – the motor and pump weighed an aggregate 26 t. Through continuous product development, Weir Minerals reduced the weight of the static walkways by 40%.

A focused engineering approach enabled the company to provide a solution catering for any possible maintenance limitations on the site, the types of pumps to be fitted, the attaching pipework, structural connections and walkways between the pontoon and land, and buoyancy, which he describes as the art of floating something and keeping it level with stationary equipment and moving objects on top.

Koorts concludes that the company has the equipment, engineering capabilities, supply chain infrastructure and process knowledge to fully support customers in their tailings dewatering applications through a solution that “works really well”.