Is There Money to Be Made in Wastewater Treatment?

The mining industry is no stranger to the devastating effects of mine wastewater. Pollution in rivers and streams and countless deaths among aquatic life have put companies under immense pressure to properly maintain, control and dispose of contaminants from their operations.

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Historically, recovering metals in wastewater has been categorized as a business cost for mining companies. It meant a substantial upfront investment in infrastructure coupled with higher energy and chemical costs which equated to one thing: more money. But is it worth it?

“[Mining firms] are pretty much stuck with treating the wastewater whether it’s economic or not,” says Adrian Brown, a wastewater consultant. “So suddenly any metal recovery is beneficial in the sense that it has the ability to either reduce your project costs or, at the very least, to dispose of the extracted material from your project at zero or no cost.”

In recent years, advances in metal-removal technology have shown there’s money to be made.

“In the large majority of mining waste, the metals of value are mixed in a cocktail that contains basically the whole periodic table of elements. A lot of these elements have no value and some of them [won’t] be removed because they are not toxic,” said David Kratochvil, interim chief executive at BioteQ Environmental Technologies.

“The trick is to be able to select the metals of value from this cocktail.”

The most frequent method for treating mine wastewater is lime neutralization. It removes the acidity but the downfall is it also makes it very difficult to extract individual metals.

One of the newest technological options for miners is sulphide precipitation. This transforms the metals in wastewater into high-grade solid metal sulphides that can be sold or disposed of.  Swiss mining companies Glencore is one of the first to employ this tool to treat mine drainage.

Along with newer technologies, Kratochvil believes policymakers can (and should) play a pivotal role in metal recovery.

“It’s remarkable how perceptions of environmental liability have changed [but] our struggle is finding the incentives for mining companies to really innovate,” he says.