Foundry and engineering company Thos Begbie last month supplied new start-up face equipment to the new smelter of Canada-based First Quantum Minerals’ (FQM’s) Zambia-based Kansanshi copper mine.
“The equipment supplied to the Isasmelt furnace includes copper-cooling components, cooling elements for the furnace shell, which can weigh up to 3 t, as well as a full set of copper launder segments,” Thos Begbie sales director Harry Müller tells Mining Weekly.
The copper-cooling components, which form the walls of the furnace, use water-cooled copper elements lined with a refractory. The elements form a protective freezing layer inside the furnace, keeping the furnace cool and preventing molten products from burning through the furnace shell.
Thos Begbie has been supplying copper-cooling components and elements to the smelter for the past two to three years.
Kansanshi Mine
Kansanshi is the eighth-largest copper mine in the world. Its Isasmelt furnace is a top-blown submerged-lance furnace and is used for smelting copper concentrate to copper matte that contains about 60% copper. The smelter will be shared by Sentinel, another FQM mine, and will process 1.2-million tons of treated copper concentrate a year.
The Kansanshi mine can produce 340 000 t of copper and more than 120 000 oz of gold a year.
FQM reported in July that the mine’s daily copper concentrate throughput averaged 3 000 t, with periods during which more than the 3 500 t/d nameplate capacity was achieved. Feed to the smelter comprised a mixture of stockpiled and fresh concentrate from the Kansanshi mine and fresh concentrate from the Sentinel mine.
Cooling Efficiency
Müller reiterates that, to create an efficient heat exchanger or cooling element for the furnace, water is circulated through the copper by means of a network of drilled holes in a copper slab or the inclusion of a Monel (a nickel/copper alloy) pipe circuit, cast into the copper casting.
“The volume and velocity of the water coolant are controlled to achieve the perfect balance for creating an effective freeze lining while not losing too much heat energy from the smelt reaction zone,” he explains.
The essence of efficient cooling is further achieved by obtaining a 100% bond between the cast copper and the Monel piping to allow for maximum heat transfer, according to the company’s website.
Thos Begbie also supplies running spares for copper miner Mopani Copper Mines’ Mopani smelter, in Kitwe, Zambia, Thos Begbie sales manager Piet du Preez says, adding that the company has been supplying spares to the Zambian smelters for at least the past ten years. These spares comprise water-cooled copper-cooling components, launder segments and tap blocks.
While Du Preez notes that the company’s business in Zambia has increased by 10% in the past two years, attributing the increase to the project work for the Kashanshi smelter and the supply of running spares to the Mopani smelter, Müller acknowledges a current lack of major projects in the mining industry.
Thos Begbie, nevertheless, installed two new Femco five-axis computer numerically controlled (CNC) boring mill machines at its premises in Middelburg, Mpumalanga, in February and April, Müller notes.
“This acquisition has increased the company’s fleet to five five-axis CNC boring mill machining centres at the heavy machining facility and, subsequently, its capacity to supply components to industry,” he says.
The 16.7 ha premises also comprise a pattern shop and copper foundry.
Large copper castings are made and machined to order at the ISO 9001:2008- rated facility for the worldwide pyrometallurgical industry. Castings are also made from other metal and copper alloys, including aluminium, bronze, brass, cast iron and stainless steel.
The company’s other facilities include a large refurbishing, fabrication and boiler shop, as well as a preassembly unit where clients can inspect their manufactured components.