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.
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.
Rio Tinto and Alcoa begin construction with ELYSIS tech
Eliminating all direct greenhouse gases from aluminium smelting has taken a major step forward with the start of construction on the first commercial-scale prototype cells of ELYSIS’ inert anode technology, at Rio Tinto’s Alma smelter in Saguenay-Lac-Saint-Jean, Quebec.
ELYSIS has the potential to reduce the carbon footprint of aluminium production
ELYSIS is a joint venture company led by Rio Tinto and Alcoa that is developing a new breakthrough technology, known as inert anode, that eliminates all direct greenhouse gases (GHGs) from the traditional smelting process and instead produces oxygen.
The technology has the potential to transform the aluminium industry, with a significant reduction in its carbon footprint.
The inert anode prototype cells will operate on a commercial scale typical for large modern aluminium smelters, using an electrical current of 450 kiloamperes (kA).
The Honourable Francois-Philippe Champagne, Minister of Innovation, Science and Industry joined representatives from ELYSIS, Rio Tinto and Alcoa to mark the start of construction and announce a further CAD $20mn financial contribution from the Government of Canada to support the project.
The federal government's financial support will enable the creation of a unique commercial size inert anode technology showroom for future customers and will help develop the supply chain by involving local and regional equipment manufacturers and suppliers in the project.
ELYSIS is working to complete the technology demonstration by 2024 followed by the commercialization activities.
ELYSIS technology at a glance:
- The ELYSIS technology addresses the global trend towards producing low carbon footprint products, from mobile phones to cars, planes and building materials.
- The new process will reduce operating costs ofaluminiumsmelters while increasing production capacity. It could be used in both new and existing aluminium smelters.
- In Canada alone, the ELYSIS technology has the potential to reduce GHG emissions by 7 million tons, the equivalent of removing 1.8 million cars from the roads.
- ELYSIS will also sell next-generation anode and cathode materials, which will last more than 30 times longer than traditional components.
Alcoa and Rio Tinto will continue to support the ELYSIS development program alongside the Governments of Canada and Quebec.
ELYSIS is working closely with Alcoa's Technical Center, where the zero-carbon smelting technology was invented, and the Rio Tinto technology design team in France.
Alcoa's Technical Center supports ELYSIS in the manufacture of proprietary materials for the new anodes and cathodes that are essential to the ELYSIS process. The Rio Tinto technology team in France is creating commercial scale designs for the ELYSIS technology.
Vincent Christ, CEO, ELYSIS commented: “This is a great day for ELYSIS. It means that we are becoming the first technology company in the world to build commercial-size inert anode cells. While we refine the technology in our R&D Centre, we start the construction of our prototype cells. This shows our confidence in our process and in the know-how of our team. The combination of ELYSIS' zero CO2 technology and Quebec's renewable energy will be great competitive advantage for the future. I would like to thank the government for its support and all the partners for their commitment.”
Samir Cairae, Rio Tinto Aluminium managing director Atlantic Operations and ELYSIS board member added: “Today marks a real step towards the future of the aluminium industry, by progressing this breakthrough technology to cut carbon emissions. Rio Tinto is committed to supporting its ongoing development here in Quebec where we already use clean hydropower to deliver some of the world’s lowest carbon aluminium. Combining this technology with renewable hydropower holds the promise of zero carbon aluminium smelting.”