Innovative Extraction Processes Could Unearth Billion of Dollars of Nickel
Australian technology firm, Direct Nickel Limited (DNi) has teamed up with CISRO scientists in Perth to develop a commercially viable method for extracting nickel from low-grade ore.
The project has the potential to impact the industry on an international scale, which could translate to billions of dollars worth of nickel made available for processing.
Traditional sulphate ore bodies are depleting and thus, the focus is shifting to laterite and saprolite ores, which contain approximately 70 percent of the world’s nickel. The new extraction technology has been six years in development since DNi sought the patent for nitric acid recycling. At the same time the firm approached CISRO regarding a collaboration to develop the process for metallurgical processes.
How the process works
The process, developed by DNi and CISRO replaces sulphuric acid with nitric acid during the high-pressure acid leaching process. Nitric acid as opposed to sulphuric acid eliminates problems associated with waste treatment and disposal and therefore is a lot more cost effective.
Furthermore, nitric acid is far more aggressive than sulphuric acid and as such can extract nickel at a much lower pressure and temperature, eliminating the need for expensive titanium lined equipment.
From small scale testing the project has grown to a $5 million pilot plant with the ability to recover 95 percent of reagents for reuse, reducing operating costs while extracting the majority of the nickel and cobalt from the deposit.
The fact that acid can be captured and recycled is a huge plus point for both parties involved owing to the fact that it eliminates the major cost associated with sulphuric acid plants; the neutralization of acid waste.
Dave Robinson, a spokesperson for CISRO Perth says: “There’s probably billions of dollars of nickel in Australia that needs this type of technology to turn it into a commercially attractive proposition. There’s a vast ore body out there that the current cut-off grade for sulphuric acid processing is too high for.”
According to Robinson, current plants such as Murrin Murrin (north-eastern Goldfields) are processing about one percent nickel. “If we can lower that [cut off grade] to 0.7 or 0.75, then there is billions of dollars worth of nickel that’s available for processing,” he says.
The process doesn’t only mean that nickel extraction from low-grade ore will become an economically viable possibility; it will become an environmentally viable possibility as well. During the process all NOx gases are captured and converted to reusable nitric acid and any leach residue is mainly silicates with minor residual nitrate content. Furthermore any nitrates caused by the residue, break down to form usable nitrogen for plant growth and return to the natural Nitrogen Cycle.
Production of saleable magnesia solves the magnesium disposal problem experienced by HPAL operations. According to DNi the mass of waste residues is less than half that of HPAL processes due to minimal disposal of reagent and neutralising agents – and production of saleable co-products. This is a major advantage in high-rainfall tropical environments.
“In summary [the process is] a highly efficient and elegant solution to the world’s nickel supply problems,” states DNi.
As Robinson concludes, “You can change the value of what is in the ground in Australia.”
The next stage of the project is to build a 30,000 tonne per annum nickel plant to demonstrate full-scale production and DNi is currently seeking a partner to develop such a plant. CISRO has spoken out to confirm that it will continue to develop the extraction process for wider application in the mining industry. Watch this space.
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.”