Mine ventilation, refrigeration and cooling engineering consultant BBE Group says it is on track to complete a turnkey project for the design and construction of the refrigeration plant and fan station at platinum group metals (PGMs) miner Northam Platinum’s Zondereinde No 3 Shaft project.

Northam Platinum’s first plant is of equal scope and magnitude and took more than 30 years to be phased in, in contrast to this project, which is due to be commissioned in as little as five years.

“The most unique feature of this plant is the size,” says BBE projects director Andrew Branch, adding that it will be the “single largest built refrigeration system in South Africa for at least ten years”.

“Ventilation and cooling form an integral part of the operational plan for Northam Platinum’s new block of ground, and the miners would not be able to mine without this new infrastructure,” Branch explains.

The project comprises two phases, with all works that are under way remaining on schedule.

The first phase is expected to be commissioned by the end of November 2024 and operational before Christmas 2024, with the second phase scheduled for commissioning in April 2027.

The Zondereinde No 3 Shaft project, near Thabazimbi, in Limpopo, is a major expansion drive that will result in the construction of three new shafts on a block of ground on the western limb of the Bushveld Complex.

The flagship expansion project also comprises the completion of the No 3 Shaft barrel development at a depth of 1 380 m, which will be equipped for personnel and materials handling, while another two shafts, still under construction, will handle ore and ventilation for the mine.

The expansion is predicted to extend the life-of-mine by an additional 30 years.

Branch says the company was appointed to design and build the large surface refrigeration plant to chill service water and provide air cooling for the underground works, as well as an upcast fan station on the ventilation hole.

“Zondereinde No 3 Shaft is currently one of the biggest projects in the South African mining industry and we are very proud to be a part of it.

“We are executing a design for the mine, drawing on all the industry norms and our experience to give the client the right solutions,” he adds.

Principally, BBE will install ten refrigeration machines into the surface refrigeration plant, which will ultimately have up to 70 MW of cooling capacity, during the three-year project.

The company broke ground in October last year, starting with civil works for the major structures of the plant.

Branch points out that the majority of the equipment for the project has been sourced in South Africa, and naturally, the original- equipment manufacturers (OEMs) will source a combination of local and imported parts and materials.

He says the major exception is the refrigeration machines, which are fully manufactured in San Antonio, Texas, in the US, and then imported to South Africa. The refrigeration equipment is then shipped to Durban and then trucked from port to site.

“It’s quite an extensive logistics exercise; however, it eliminates having to reassemble the equipment on site, which is an added step in the process.”

However, Branch suggests that, owing to this being a greenfield project, it has been a “straight-forward experience so far” in terms of establishing the site and “getting the work moving” on the project.

Branch says a challenge for the project has been the slow recovery of global supply chains, owing to the disruptions caused by Covid-19, and the conflict in Ukraine.

“This has particularly affected us in terms of OEMs getting the right materials for the refrigeration equipment, and it also has a knock-on effect for any equipment that has electronic items, control cards and programmable logic controllers (PLCs).”

He stresses that the best way of mitigating this issue is to give the OEMs time to start the procurement process as soon as possible.

Consequently, in the build-up to this project, BBE ensured that the packaged refrigeration machines were ordered prior to the end of last year, consequently allowing for the installation of the machines to be scheduled for the beginning of next year, with commissioning taking place towards the end of the year.

“So, we’re giving the OEMs as much time as possible to obtain the special material that will go into the heat exchangers, book the slots in their factory, and source all the electronic components,” he says.

BBE has a specific plan in place to order the control systems, PLCs, supervisory control and data acquisition equipment, and the primary switchgear, by May or June this year.

“Giving all the players as much time as possible to get their work done, corresponds with the contract setup and works with all the contract arrangements that we have with the mine,” he concludes.