The expansion of Zambia’s Lumwana copper mine, with the construction of the new Chimiwungo pit, is progressing well, with equipment supplier Bateman Engineered Technologies’ (BET’s) bulk materials handling unit having delivered more than 90% of the steelwork for the three conveyors that span almost 4 km in total. The conveyor system will feed copper ore from the new run-of-mine tip, by means of the three conveyors, to the current stockpile, which feeds the mine’s 25-million-ton-a-year processing plant.
“Erection of the steel structures is mostly complete and the last of the mechanical equipment is being delivered to the site for installation,” says Bateman’s bulk materials handling and equipment supply division marketing manager, Philip le Roux.
Bateman was awarded the contract to design, supply, deliver, erect and commission the conveyor system for an extension to the Lumwana copper mine in April last year.
The conveyor will have to negotiate a creek crossing on the longer overland conveyor section. The ground profile requires special design features, including flywheels on the drive side and a brake on the tail side to maintain belt tensions, which prevent the belt from collapsing when the conveyor stops.
This is the first time that Bateman’s bulk materials unit is working in Zambia, which is why Le Roux says he is particularly pleased with the project’s progress. “We’ve recently done work in Namibia, Mozambique and Botswana, but this is the furthest north we have worked in sub- Saharan Africa in recent times.”
He adds that he has been impressed by the stability and efficiency of the Zambian workforce, with Bateman having employed a Zambia-based consultancy and project management company, Karlsons, to undertake its on-site erections. Karlsons is also operating as a Bateman agent in Zambia for the distribution and installation of process equipment, manufactured under the Delkor brand (part of BET).
Most of the mechanical equipment for the conveyor project was sourced from South Africa.
Bateman’s steel supply for the project, which totalled about 550 t, was also sourced in South Africa and transported to Zambia. Le Roux commented that logistics posed an interesting challenge when delivering the steel and mechanical equipment to Lumwana, but says this was nothing Bateman had not dealt with before.
The bulk materials team also had to overcome challenging weather conditions, as they worked through Zambia’s wet season, says Le Roux. As a result, the team had to adhere to strict safety standards and precautions set by the mine’s stakeholders to ensure the safety of individuals, while simultaneously dealing with wet conditions at the expansion project.
“Bateman is committed to the principles of zero harm, implementing health and safety executive-based regulations, policies and procedures, where possible, to avoid any preventable injuries,” he adds.
The Lumwana expansion project includes a significant exploration programme to increase the measured and indicated resources for the expansion study, which the owner, gold producer Barrick Gold, expects to be complete in the second half of this year.
The expansion study, which was initiated as Lumwana’s Malundwe pit, is reaching the advanced stages of its current life, with its Chimiwungo pit required to supplement ore feed to the process plant from August 2012, says Le Roux.
Barrick Gold sees lower cash costs at its Lumwana mine in 2013 as mining at the copper project moves from mining lower- grade material in the Malundwe pit to the new Chimiwungo pit, CEO Aaron Regent told Reuters in March this year.
The contract for Lumwana’s original $408-million engineering, procurement and construction management (EPCM) project for the development of the mine’s 20-million-ton-a-year copper processing facility was awarded to Bateman and Ausenco in 2006.
In January, Ausenco reported that it had signed an EPCM contract to manage a $125-million expansion of Lumwana.
Ausenco’s minerals and metals business is managing the project, which involves expanding the existing ore crushing and processing plant at Lumwana to achieve and maintain a plant production rate of 25-million tons a year. The expansion will be completed by June this year, says Ausenco CEO Zimi Meka.
Focusing on Efficiency
Although there are few current technological advances in the bulk materials handling industry, Le Roux tells Mining Weekly, there is a keen focus on efficiency in the sector. This includes implementing solutions that require less power consumption, making sure that all machinery is of the highest quality and promoting research to achieve lower roll resistance in conveyor belts, for instance, or to seek out idlers and belts with lower friction factors.
He points out that there currently is no specific advanced or cutting-edge technology in the bulk materials industry, which he describes as being more mature in terms of technological development. “There is, however, much research being done to further develop and optimise drive systems and other components relating to the industry.”
Le Roux also emphasises that BET strives to maintain high standards regardless. “The company always tries to ensure that we use the best of the best. Therefore, we only use reputable international suppliers that provide an aftermarket service for the client.”
Internally, Bateman focuses on optimising efficiency. “It’s about intuitive design and ensuring that our systems are designed for optimal efficiency, from the steel structures in terms of overall mass and functionality to optimising the system to ensure that it meets specified standards and requirements,” says Le Roux.
He notes that the competitive aspect of the industry has become cost-driven, and that delivering a high-quality project at lower cost attracts various international clients.
“This means getting the best people on site to ensure that work is performed right the first time. It’s all about erecting safer, faster and cost effectively,” he says.
The Future of Copper
While base metals are not the main focus of the bulk materials handling sector, as is the case with coal and iron-ore, there is currently significant interest in copper, especially with the favourable copper price, says Le Roux.
“There are many feasible business opportunities in Africa, and substantial exploration is being undertaken in the Zambia/Democratic Republic of Congo Copperbelt area, amongst other regions.”
Le Roux adds that copper, as opposed to alternative base metals projects, is particularly attractive to Bateman’s bulk materials handling business, because of the strong need for bulk materials handling in the copper industry.
“Copper mining often uses openpit mining, which requires trucking, shovelling and, ultimately, conveying, which is one of Bateman’s areas of expertise.”