Tag Archives: GlyLeach

Draslovka’s glycine leaching tech to be tested on gold, nickel tailings at Windarra

Draslovka a.s. subsidiary Encore Minerals, a company established with the specific aim of progressing waste to value opportunities, has entered into an agreement with Poseidon Nickel to retreat and monetise gold and nickel tailings in Western Australia.

Draslovka’s proprietary Glycine Leaching Technology (GLT), comprising the GlyCat™ process for precious metals and GlyLeach™ process for base metals, will be an enabler for the extraction of
realisable value from Poseidon’s gold and nickel tailings at its Windarra property and potentially from a third-party tailings resource at nearby Lancefield (the Windarra Tailings project), Draslovka says.

Previous metallurgical test work for the Windarra Tailings project had shown potential improvement in recoveries and costs for the site’s gold resources. The test work also established the potential for a technical, economically viable and low-intensity process for recovery of nickel from nickel tailings. A previous feasibility study for the gold resource using conventional cyanidation showed net operating cash flow of A$30.6 million ($19.9 million), a net present value (8% discount) of A$21.7 million and an internal rate of return of 50.6%, assuming a gold price of A$2,500/oz.

The next step is to undertake a technical program to optimise the project with both the gold and nickel resources, which will lead to an updated feasibility study and a final investment decision. If
successful, the project will lead to the construction of the first GLT processing plant for tailings.

Ivor Bryan, Chief Technology Officer of Draslovka Mining Process Solutions, said: “We are excited to play an integral role in enabling the retreatment of the gold and nickel tailings at the Windarra Tailings project by supplying GLT, which has been developed to extract precious and base metals.

“GLT is revolutionary for the mining industry. It has the potential to save mining companies billions of dollars by significantly reducing processing costs, enhancing a mine’s sustainability profile, extending mine life by lowering the cut-off grade and unlocking value hidden in a mine’s tailings. I believe the results at Windarra will be a powerful example of how GLT is a simple yet very effective means to retreat and monetise tailings.”

Draslovka about to move into glycine leaching mining demonstration phase

Czech Republic-based Draslovka Holding is heading into a busy 12-month period where its glycine leaching technology will be showcased at numerous mining projects across the globe, the company told IM on the side lines of the Resourcing Tomorrow conference, in London, this week.

According to Ivor Bryan, Director of Mining Innovation at Draslovka Mining Solutions and the former MD of Mining & Process Solutions (MPS), the entity responsible for the development of the GlyCat™ and GlyLeach™ technologies, the company is embarking on around 10 projects in the mining space, which will prove up the 3,500 hours of testing that has been conducted at MPS’ facilities in Perth, Western Australia.

MPS was acquired by Draslovka, a major sodium cyanide producer in 2022, with the aim of the transaction being to grow and develop the glycine leaching business.

Gold leach testing via GlyCat has been the major area of focus over the last decade. The process was invented to reduce cyanide consumption while maintaining gold recovery for gold ores from deposits containing nuisance copper. It has been designed to enhance the dissolution of gold and copper in gold/copper ores where glycine is used as a catalyst with cyanide in a cyanide-starved leaching environment. It doesn’t replace cyanide, but, in fact, enhances its leaching capabilities by dealing with the high-cyanide consuming copper within these gold-copper orebodies.

Yet, the company is also now starting to make inroads into the base metal space through GlyLeach, with nickel and cobalt two specific areas of interest. The technology is able to leach the targeted metals with enhanced selectivity compared with conventional methods. It will solubilise copper, nickel, cobalt and zinc, while gangue minerals such as iron, manganese, silicates and carbonates remain in the leach residue, Draslovka says.

This is allowing the company to promote that it can reduce the capital expenditure associated with processing these metals by removing the need for smelting, or in the case of tailings deposits, helping recover metal from assets previously written off as ‘waste’.

While the technology could have applications at run of mine operations, Bryan and his colleague Jackson Briggs, Corporate Development Manager of Draslovka, believe the most immediate opportunity is in tailings where the application of glycine leaching on ‘waste’ material could recover valuable metals while reducing the potential liabilities associated with such storage facilities.

Of the 10 or so projects the company has ahead of it, one is situated in Western Australia where the company is looking to recover nickel and cobalt metals from a tailings deposit of a major mining company.

Another project – much closer to fruition – is in Chile and involves leaching a carbonate-hosted copper oxide deposit containing some 600 t of material.

In both cases, the company is looking to demonstrate that it can recover valuable metals at high recovery rates, with low impact – namely rationalising reagent and water use and, in the case of nickel-cobalt, removing smelting from the equation.

This, according to Draslovka CEO, Pavel Bruzek, is a “win-win” for mining companies and their stakeholders, benefitting both the balance sheet and the operational environmental footprint.

“While we are a major sodium cyanide producer, when we saw the potential of MPS’ glycine leaching technology and the increase in metallurgical complexity of orebodies looking to be exploited, it made perfect sense to work with and promote this technology,” he told IM. “It is the responsible thing to do for the industry.”

Draslovka eyes base metal leaching prize with MPS glycine technology

Draslovka Holding made its presence felt in the mining chemicals space about a year ago when it announced plans to acquire Chemours Company’s Mining Solutions business, a deal that has since seen it become one of the largest North American producers of solid sodium cyanide.

This acquisition, completed in December for $521 million, also laid the groundwork for a separate transaction that could see the Czech Republic-based company diversify into the in-demand battery metals arena.

Australia-based Mining & Process Solutions (MPS) had been on the Mining Solutions business radar for at least two years prior to the Draslovka transaction, according to James Stockbridge, Director of Draslovka Mining Solutions. Stockbridge, formerly of Chemours and DuPont, said that his team at Draslovka realised MPS had something on its books that could solve many of the challenges the industry was experiencing and transform mining solutions by using an amino acid called glycine.

“For more than a decade now, the industry has recognised that orebodies are becoming lower grade, processing them is becoming more complex and the environmental regulations associated with leaching are becoming stricter,” Stockbridge told IM.

“It is the challenge of our time, and we think MPS has something quite unique to offer here.”

With roots in the gold technology group at the renowned Curtin University in Western Australia, MPS’ glycine leaching technology has the potential to change both the gold and base metal leaching space.

In gold, MPS’ GlyCat™ process was invented to reduce cyanide consumption while maintaining gold recovery for gold ores from deposits containing nuisance copper. GlyCat has been designed to enhance the dissolution of gold and copper in gold/copper ores where glycine is used as a catalyst with cyanide in a cyanide-starved leaching environment. It doesn’t replace cyanide, but, in fact, enhances its leaching capabilities by dealing with the high-cyanide consuming copper within these gold-copper orebodies.

In copper, nickel, cobalt and zinc leaching, GlyLeach™ is able to leach the targeted metals with enhanced selectivity compared with conventional methods. It will solubilise copper, nickel, cobalt and zinc, while gangue minerals such as iron, manganese, silicates and carbonates remain in the leach residue, MPS says.

Both technologies are environmentally safe, work effectively at alkaline pHs and ambient temperatures (with no heating cost or pressure vessels) and come with low operating costs due to their low consumption and recovery/recycling traits, according to the company.

While it is the gold side of glycine leaching testing that has, so far, taken the headlines thanks to several trials with mining companies in Australia (including Evolution Mining) and the technology’s potential ability to partially replace cyanide in the leaching process, Stockbridge and his colleague Jackson Briggs (Corporate Development Manager for Draslovka) said Draslovka was most excited about what the technology could offer the base metal space.

Briggs said: “It gives us the opportunity to expand our leadership position in gold leaching agents into base metals. At the same time, it also allows us to incorporate our expertise in that chemistry and chemical manufacturing side of things.”

Stockbridge – not wanting to give away too much – hinted at how this latter opportunity could play out.

“The leaching technology will also influence the way you, for instance, operate, monitor and control the plant,” he said. “This process will be different, and we will be bringing in new technologies to cater to this.”

Considering Draslovka can produce glycine from its existing hydrogen cyanide production footprint, there is potential for a very smooth integration on the supply chain side of things.

Asked to quantify some of the benefits of the technology, Stockbridge was happy to point out GlyLeach’s potential to “simplify the flowsheet” for, say, nickel production, removing the smelting aspect and resultant ore transportation – providing capital and carbon footprint benefits.

Briggs added: “It can change a lot from ore-to-ore with GlyLeach, but, in a really strong business case, you are looking at a 25% reduction in processing costs.”

This is on top of a 10-35% improvement on the recovery side, compared with conventional leaching, Stockbridge said, citing “proof of concept” studies.

As for GlyCat, the sweet spot – as already hinted at – is in gold-copper orebodies where copper is a large cyanide consumer, with the technology allowing cyanide to work more efficiently and effectively.

Both technologies recently featured in OZ Minerals Ingenious Extraction Innovator challenge outcomes publication, while GlyCat has also been the subject of a one-off study looking at combining it with Sixth Wave Innovations’ IXOS® molecular imprinted polymer for gold extraction.

Australia’s Future Battery Industry Cooperative Research Centre, which is sponsored by the likes of Sandfire Resources, Barrick Gold, Coda Minerals (previously Gindalbie Metals) and Poseidon Nickel, is also coordinating some of the work towards commercialising GlyLeach.

There is a strong business case for both technologies first being deployed at scale on tailings deposits that have been deemed to have no associated value – a point both Stockbridge and Briggs acknowledged.

Briggs said: “In terms of accelerating the development of the technologies, there are tailings deposits and waste piles situated all over the globe with high amounts of precious and base metals that have not been extracted due to the limitations and economies associated with current processing technology. We could provide an economic way of extracting those.

“It would also provide us a project with much reduced start-up times compared with, say, a greenfield project.”

Stockbridge added: “We have carried out some work on this type of application before and believe there is the potential to extract 50% of the nickel that they couldn’t access with existing technology by using GlyLeach.”

From the mining company perspective, deploying a new technology on material already written off comes with a lot less risk too.

That is before appreciating that the material won’t have to be smelted on site, that the process produces no free cyanide and that gangue materials do not come out in solution.

It is no wonder the Draslovka duo are excited about the technology’s potential; GlyLeach in particular.

“The ability to help nickel and copper miners produce more metal to rescue some of these deposits that have been forgotten or under-developed because of technology limitations and be able to do so in a way that is more environmentally friendly is exciting.

“Potentially, this technology could help localise more electric vehicle supply chains by removing the need for smelting and providing a cost-effective and environmentally friendly means of extracting metals.

“We cannot wait to get started.”