Empire Metals cracks processing for rare titanium ore deposit

Empire Metals should make an investment decision next year to tap into its Pitfield Project in Western Australia, the world's largest titanium deposit, and eventually develop it into a mine-to-pigment one-site production facility operating at costs competitive with China, Managing Director Shaun Bunn told Platts in an interview.

The JORC-compliant Mineral Resource Estimate, upgraded in August, states that Pitfield holds 8.16 billion mt of ore with 349 million mt of contained TiO2, but due to its unusual mineral mix, it took the company over 18 months to identify the best processing steps.

"We have a mineral called anatase, which has the same TiO2 formula as rutile but a different crystal structure," Bunn said, adding that, going through dozens of flowsheet combinations, the focus was on efficiency and simplicity, avoiding the unconventional.

There are no major commercial operations globally that mine and process anatase ore as a stand-alone dedicated feedstock, though such deposits exist and metallurgical testing is underway, according to the US Geological Survey.

The Pitfield ore is also rich in aluminum clay kaolin; initially, the company treated it as a problem, but found a way to recover alumina as a by-product.

Adopting from other industries

"Our ore preparation is common, but what we use in the beneficiation circuit is a little unusual for titanium: we use flotation -- the separation technology used for 100 years to extract copper, nickel and gold," Bunn said.

"During flotation, we reject 90% of the material we mine right up front. That material hasn't been chemically altered, so can go back into the mining void," Bunn said. "Not on day 1, but we have this ability to rehabilitate behind, (which is) really important for sustainability."

The 10% of the material containing titanium will move forward for acid digestion. "At that step, we will add sulfuric acid to bring out the titanium, but we don't need to smelt the material in a high-temperature sense," he said.

Advantages over ilmenite, rutile

90% of the world's titanium is sourced from ilmenite, said Bunn. "The problem with this mineral is that it contains a lot of iron and needs tons of acid to separate titanium oxide from iron oxide," he said.

The Pitfield deposit is not completely iron-free, but compared to treating ilmenite, which contains 50% iron oxide, separating Pitfield's titanium requires half as much acid: 1 metric ton per ton of titanium. "It matters because of what happened with sulfuric acid prices," Bunn said.

"Not only is the ilmenite industry acid-thirsty, it also ends up with iron sulfate -- a big waste product. It's acidic, so it can't be put out into the landfill. They have to neutralize it with lime, and that is another cost we don't have," he said.

Empire Minerals also distinguishes itself from the 10% of titanium producers processing rutile concentrate.

"Our head grade is 5%-7% TiO2. If you look at rutile projects, mineral sands typically have 1%-2% TiO2. For the same amount of product, they have to mine 5-7x more," said Bunn.

Long-haul flights need lighter planes

Titanium demand is key to the company's future and it is going up steadily from its current 8 million mt/year. The majority of consumption is in pigment, but the titanium metal segment is growing faster, with rates closer to 7%-8%, according to Bunn.

The metal component used in the aerospace industry, which has the largest share of metal demand, is growing rapidly as fuel costs make air travel expensive. To offset those costs, titanium consumption per plane is increasing to reduce the aircraft's overall weight.

"20% of the new Boeing 777X is titanium," said Bunn. "Nowadays, you can fly direct to London from Perth or Sydney on a single flight, but only on the Dreamliner [Boeing 787], because of its weight-to-strength ratio: it's a lighter plane thanks to titanium."

"In defense, they use even more titanium to build jet fighters, long-range bombers, and drones, and they don't care about the cost. 60% to 70% of some of the jet fighters the Americans use are made of titanium. There's no doubt the US Department of War is investing heavily in titanium inventory," said Bunn.

He even assumes there will be more titanium in road vehicles.

"EVs would be a logical use for titanium to replace the heavy steel chassis, which you can't make from aluminum, it's too soft, while titanium is lightweight yet indestructible," said Bunn, but admitted that titanium has been too expensive for EVs.

"You'd have to get the cost of production down to start competing against those current materials. Your feedstock starts off at $1,500/mt. The metal costs thousands of dollars to make, and sells for $6,000 or $7,000 a ton," he said.

Despite the metal market's appealing growth rates, Empire Metals will focus on producing titanium pigments, with the possibility of supplying material to the metal industry as well.

"Producing mostly metal makes the company dependent on the government as a customer. I don't think that's a wise strategy for the project to be controlled by governments," said Bunn, and added that the use of titanium pigments is massive, allowing manufacturers to achieve significant economies of scale.

Recycling is small

He also noted the pigment industry doesn't do a lot in terms of recycling, maybe with papers, but not with paint, and so primary pigment production is key for the supply.

Recycling rates in the metal industry are likely higher, but remain constrained by titanium being locked into long-service applications.

"The industry extracts some of the titanium from golf club shafts, glass frames, certain Apple iPhones, perhaps even medical parts. You can reclaim titanium from civil crafts, and I would imagine that defense departments around the world would recycle their own equipment," said Bunn. "It would be good if you could recycle more, but the life of these things runs for 40-50 years."

Empire Metals is proceeding to mine planning, while finalizing the feasibility study and preparing to apply for environmental permits.