Technology Makes Slurry Pumping Less of a Drag
As CSIRO pointed out, almost all mineral processing plants need to transport slurry through pumps at various process steps. A thick slurry is prone to friction or a “drag effect” in the pipes, making it more energy and capital-intensive to pump, as well as susceptible to blockages.
To overcome this, water is added to dilute the slurry, but this has the drawback of lowering the ore throughput achieved. To overcome this problem, CSIRO developed a new technology that takes the energy-sapping drag out of industrial pumping. It introduces a thin, uniform and durable ring of fluid between the slurry and the inside of the pipe so that thick material can be efficiently pumped without friction at a high throughput.
The technology was first trialed by by nickel producer Minara when their feed ore slurry pumping systems began overloading as they steadily increased their ore throughput. The company’s initial response was to operate both the duty and stand-by pumps in parallel; however, this quickly became constrained. The alternative of further diluting the slurry was not an option because it would reduce metal recovery and negatively affect reagent use in the downstream process.
CSIRO said it worked with Minara Resources to initially identify a low-cost installation point with good potential for addressing the challenge. Installing the drag reduction technology provided a 20% reduction in pressure to free up capacity in their slurry pumping system.
Minara Resources has since adopted the drag reduction technology at its Murrin Murrin nickel operation. Implementation allowed the company to avoid an expensive upgrade to its existing plant to meet throughput demand.
CSIRO said it believes the technology can save mining companies millions of dollars on energy and water use each year, while boosting their productivity. It conceivably could be applied to a broader range of industrial processes where there’s a dewatering aspect that results in a sludge, slurry or paste that needs to be transported. For mining, the technology allows variations in the ore’s viscosity or water content to be easily managed.