Mining Mirror March 2019 | Page 37

Mining in focus Peristaltic pumps use less water. obstacles of pumping solutions for specific mining applications can be complex — and these companies simply cannot afford the potential high cost of losses — in operations, operational efficiencies and the costs of equipment churn that can be caused by having an inferior solution. One operational area that stands to benefit significantly from innovations that can assist with dewatering, is mineral processing. For instance, there are many cases — and across Africa — where a mineral processing plant has been developed on site, or nearby, but there aren’t smelters for the beneficiation of the product afterwards. This means that mine companies are paying to transport a product to the beneficiation plant, but because it still contains so much water, the company loses out on the cost of the water weight versus tonnage of product transported. Currently, few traditional centrifugal pumps on the market are able to transfer slurry at the high SGs required to save water, and those that can will certainly experience increased wear rates. Slurries are often acidic and/or highly abrasive. Consequentially, conventional slurry pumps use impellers made from increasingly expensive materials with service lives that are sometimes measured in mere days. www.miningmirror.co.za As water scarcity becomes a reality, mining companies are faced with numerous civil and environmental pressures. “Verderflex peristaltic hose pumps are the ideal solution for demanding applications such as mining thickener slurries and highly abrasive, high-density, and shear-sensitive or corrosive liquids,” says Macdougall. These pumps have earned a reputation as the mining industry’s slurry pumping workhorse. They are designed to pump slurry at a higher SG at a steady flow rate, which significantly reduces the amount of water-to-product ratio, thereby increasing the per tonnage of product being transported. How does a peristaltic pump work? Peristaltic pumps work by alternating compression and relaxation of a hose or a tube, drawing fluid in and propelling it away from the pump. A rotating shoe or roller passes along the length of the hose or tube, creating a seal between the suction and discharge sides of the pump. As the pump’s rotor turns, this sealing point moves along the tube or hose, displacing product into the discharge line. The hose or tube recovers after the pressure has been released, creating a vacuum. This is the priming mechanism that draws the product into the suction side of the pump. Combining these suction and discharge principles results in a powerful self-priming positive displacement action, the benefits of which are a gentle pumping action at a low velocity with no product degradation. MARCH 2019 MINING MIRROR [37]