Engineering firm helps create ‘clean’ antimony and gold processing plant

Wakefield-based thermal and metallurgical engineering firm Inprotec has completed a seven-figure project to support the creation of the world’s first ‘clean plant’ antimony and gold processing facility in Sohar, Oman.

The facility, known as an antimony roaster, is the largest of its kind outside of China and the world’s first clean plant, designed and built to EU environmental standards.

Created by Strategic & Precious Metals Processing LLC (SPMP), it has the capacity to produce more than 50,000 ounces of gold per annum and 20,000 tonnes of the rare and critical metal, antimony, which is used to fireproof printed circuit boards and other electronics, and often alloyed with other metals such as lead for use in lead-acid batteries.

Inprotec was approached by SPMP and lead engineering contractor Worley Parsons in recognition of the company’s industry expertise in designing, supplying and commissioning bespoke furnaces used to melt, smelt and refine non-ferrous and precious metals.

During the two-year project, Inprotec designed, manufactured, and commissioned two drum-style furnaces, known as refining converters, which are used to remove any impurities in the final stage of refining antimony.

It also provided all of the ancillary plant required to support the two refining converters, including a trough-like molten metal launder system to carry molten alloys from one location to another using gravity, and an air lancing system used in the refining process.

Once fully operational, the plant is expected to account for between 12-15% of the world’s antimony production, establishing Oman as a major global producer of this rare and critical metal.

Inprotec MD, Chris Oldroyd, said: “Most people haven’t heard of antimony as it’s not the headline grabbing commodity that gold is, but it has been categorised as a critical raw material in recent years due to the fact that it’s used widely in electronics.

“Over the last two years we’ve worked closely with SPMP to design, supply and commission world-leading plant that enables them to cost-effectively, efficiently and safely refine antimony.”

David Fourie, smelting manager at SPMP, said: “Not only is this the first antimony roaster to be built outside of China in the last 30 years, but it’s also the world’s first ‘clean plant’, designed and built to the highest environmental standards.

“It’s an incredible feat of engineering and Inprotec’s skilled team have played a key part in helping us to realise this hugely impressive plant and its world-leading capabilities.”