|Hydroacoustic sensors that measure the direction and speed of currents in water columns, deployed by DeepGreen Metals Inc. in October 2019 in the NORI D project area in the Pacific Ocean's Clarion Clipperton Zone.
Source: DeepGreen Metals
DeepGreen Metals Inc. is in talks with a number of parties to colocate its planned processing plant with manganese alloy producers near hydropower, having successfully derived an alloy of base metals from polymetallic nodules on the Pacific Ocean floor.
The Canadian company announced Oct. 17 that it will perform confirmatory tests using more than 100 tonnes of nodules in early 2020 to enable the design of a commercial plant.
DeepGreen and Kingston Process Metallurgy Inc. obtained an iron-rich alloy nugget containing high recoveries of nickel, copper and cobalt by replicating calcination and smelting processes initially developed in the 1970s and using nodules obtained from a recent expedition to the Pacific Ocean's Clarion-Clipperton Zone, or CCZ.
A manganese silicate product used in the manganese-alloy industry was also produced.
DeepGreen is doing further test work and engineering that will lead to a pilot plant project in 2020 to demonstrate the metallurgical flow sheet at scale to produce nickel and cobalt sulfate and copper cathode products with no solid waste.
Brisbane, Australia-based chief development officer Anthony O'Sullivan said DeepGreen will also produce an ammonium sulfate fertilizer and a converter slag, which is essentially an iron silicate material suitable for road aggregate particulate material, railway ballast, cement manufacturing and abrasives.
O'Sullivan told S&P Global Market Intelligence that given the nodules are on the tidewater when they are brought up, there is a "high degree of freedom" as to where the onshore facility can be located.
O'Sullivan said DeepGreen is in discussions with a number of parties as to where to locate the plant, ideally near electricity-intensive manganese alloy producers, which are often near hydropower sources, as the company plans to use rotary kiln electric arc furnaces similar to the processes needed to produce manganese alloys.
DeepGreen plans to be in production by 2024 or 2025 and hopes to secure a partner with which to colocate its onshore plant within the next 18 months.
The company welcomed offshore pipeline installation, heavy-lift and subsea construction company Allseas Group SA as a shareholder earlier this year as part of a US$150 million private equity investment round. The oil and gas player will assist with the nodule extraction.
DeepGreen will also finalize a white paper in the coming weeks looking at a full life cycle analysis of the environmental impacts of producing battery materials from metals sourced from the ocean, versus terrestrial mining, based on existing literature.
O'Sullivan said the company estimates that its process will have between 10% and 20% of the average carbon impact of producing batteries from current terrestrial copper, nickel and cobalt mines.
"So there's a big advantage on a couple of fronts, particularly on the climate change impact, and given there's no tailings at the mine or processing plant [with DeepGreen's process]," O'Sullivan said.
The CCZ is the world's largest undeveloped nickel and cobalt deposit "by an order of magnitude," O'Sullivan said, adding that about a quarter of the International Seabed Authority's resource estimate for the CCZ would be sufficient to electrify the world's entire light vehicle fleet.
A slide from a recent DeepGreen presentation said the International Seabed Authority's resource estimate for the CCZ totals 34 billion tonnes of nodules — 6 billion tonnes of manganese, 270 million tonnes of nickel, 234 Mt of copper and 46 Mt of cobalt — and would be enough to electrify 1 billion cars four times over.
DeepGreen's NORI project has a resource of 909 million tonnes of wet polymetallic nodules grading 1.3% nickel, 29.2% manganese, 1.1% copper and 0.2% cobalt, and O'Sullivan said at this year's Prospectors & Developers Association of Canada conference that its indicated resource now totals 33.7 Mt grading 17.14 wet kilograms per square meter.
"When you perform a life cycle sustainability analysis as we have done, and you look at the dynamic and interacting systems of the whole earth — rain forests and mountains, deserts and oceans — it becomes clear that obtaining critical base metals from ocean nodules has the least impact in terms of biodiversity, carbon, ecosystem services and human communities," DeepGreen's chief ocean scientist, Greg Stone, said in the Oct. 17 statement.