"Starting at the front end, the crushing and grinding process is no different for recovering “free gold”. Where Clean Mining differs is at the next stage, taking the gold that remains in the ore and putting it through a leaching process for a residency of up to 24 hours depending upon the type of ore. We then have the option of producing dry tails utilizing our dewatering solution, which can negate the use of tailings dams and can recycle water and unused reagent."
What were the circumstances surrounding the creation of Clean Mining?
The Commonwealth Scientific and Industrial Research Organization (CSIRO), the Australian federal government agency responsible for scientific research, was commissioned over a decade ago to tackle a particular problem ore in the US that could not be processed with cyanide and needed a non-toxic solution. After spending a considerable amount of time and money developing this solution, CSIRO approached our company, a separate gold mining lease holder in Australia at the time, to test this technology in the field. We proceeded to form a collaboration agreement with CSIRO on the basis that, should it be proven in the field, we would take on the commercialization rights and buy the patents. In 2018, Clean Mining group via is R7D parent company partnered with CSIRO to build the first Clean Gold processing plant to refine and test the technology in an industrial setting.
Today, Clean Mining focuses on this non-toxic solution within the gold mining industry, and we have also collaborated with Flinders University in South Australia for complementary technology in the gold space, which not only includes gold recovery technology applicable to artisanal and small scale miners, but also the remediation of heavy metals such as mercury from the process. The company’s mandate is to focus on technologies that are environmentally friendly, but also make business sense and are commercially viable.
Can you explain how this technology works?
Starting at the front end, the crushing and grinding process is no different for recovering “free gold”. Where Clean Mining differs is at the next stage, taking the gold that remains in the ore and putting it through a leaching process for a residency of up to 24 hours depending upon the type of ore. We then have the option of producing dry tails utilizing our dewatering solution, which can negate the use of tailings dams and can recycle water and unused reagent. On average we would use approximately 2kg of reagent per tonne of ore.
How does Clean Mining’s process compare to gold recovery using cyanide?
We have found Clean Mining’s technology is the equivalent of cyanide in almost all cases. However, we find that we can have better recovery in carbonaceous ores. We have been inundated with interest from all over the world, with over 600 leads from miners, with a number of these already moving into testing which is the first step of our validation process. This testing includes initial analysis on the recovery variables using the reagent.
In January 2020, Clean Mining’s technology took the top award in the mineral processing category at the Mining Magazine Awards. When you consider all facets of the process and comparative overall operating costs including OH&S, tailings dams, logistics, not to mention the associated approvals etc, I can say categorically that our solution is no more expensive than cyanide.
What types of gold mining operations are most apt for the use of Clean Mining’s solution?
Clean Mining’s technology is scalable for both large and small-scale operations. However, so far, we have had significant interest for solutions between 20 tonnes per hour (mt/h) to 250 mt/h with our ability to produce mobile solutions of up to approximately 100 mt/h to focus on high grade, low volume, stranded assets, which would not necessarily meet the operational ROI for a lot of mining companies and would not justify the investment of a fixed, entry point cyanide plant.
Additionally, in Western Australia in the 1800s the government had 72 state batteries, where a lot of small and medium-scale miners processed their ore. Clean Mining is also currently working with its partner Nu-Fortune Gold to re-create this “hub” concept around these Western Australian gold fields, which will hopefully expand the adoption of our clean technology.
How is Clean Mining approaching the artisanal mining industry?
We know our technology works at this scale, however, we are looking at how we can provide an efficient, cost-effective and non-toxic solution for artisanal mining in South America, Asia and Africa. Time is of the essence for many artisanal miners, who do not have the capital to invest in costly and non-efficient processes and technologies. Furthermore, many do not always have the awareness of what mercury can do to both themselves and the ecosystem. At present we are looking at refining processes for small teams using portable agitation drums that can be used on site, but the concept of hubs within an artisanal network where different groups can bring their ore in and get it processed at a central processing center is gaining some interest. We went to Mining Indaba in Cape Town in February, and we are in early discussions with various groups including NGO’s and government bodies to get the first Clean Mining artisanal pilot project set up.
Do you have a final message for potential partners in the mining industry?
Clean Mining has a true, non-toxic solution, and we would like the opportunity to test and prove the technology with mining companies to show that it is a cost effective solution, regardless of the scale of an operation. Currently, we are building a partner and agent distribution model to help commercialize Clean Mining’s technology, rather than setting up sales offices around the world.
As lockdown is eased around the world, certain companies might take their eye off the ESG focus due to difficult economic conditions. However, Clean Mining offers a clear value proposition that, as well as being environmentally friendly, is cost competitive with any of the alternatives.