Cementation Africa is leveraging its decades of experience in shaft sinking and underground mining at Mopani Copper Mines’ Mindola shaft in Zambia – paving the way to extend the life of the Nkana mine at Kitwe and to improve its mining efficiencies.
The scope of work comprises construction and erection of the permanent headgear including the rope-up and commissioning of the winders to enable detailed 3D scanning of the shaft to determine alignment correction and structural reinforcement to ensure safe and efficient conveyance operation. In addition, the project also includes the Installation and commissioning of an overland conveyor system.
According to Ben Adendorff, Cementation Africa’s In-Country Executive for Zambia, the focus is on readying the Mindola shaft for production – by sliping and equipping the remaining 500 metres.
“To determine the exact degree of misalignment, Cementation Africa will complete a 3D scan of the complete shaft,” Adendorff says. While another contractor raisebored this particular shaft, Cementation Africa successfully completed the sinking and equipping of Mopani’s Synclinorium and Mufulira Henderson shafts over a decade ago. The sinking and equipping of the 1,280 m Synclinorium shaft – at 7 m diameter – was conducted between 2011 and 2014 and was then equipped for commissioning and handover in 2016 The sinking and equipping of the 1,580 m Mufulira Henderson shaft – at 6 m diameter – was commissioned in June 2020.
“Our current work at Mindola includes the removal of the sinking headgear and winders, and the installation of a new permanent headgear, after which we can rope-up and commission the new winders,” he explains. “This will allow us to scan the shaft from top to bottom with specialised equipment, including the length of shaft already equipped above a depth of approximately 1,000 m.”
This will allow the verifying of the correctness of the existing steel members that will guide the conveyances down the shaft, and addressing of any issues identified. Below the 1,000 m mark. The bottom 500 m of the shaft barrel will then be sliped and lined to ensure a true vertical line through which the conveyances can travel safely.
“We will the proceed with the equipping of the shaft and construction of the loading box steelwork at the shaft bottom,” he says.
The company’s legacy in some of Africa’s deepest and most challenging shaft-sinking projects has been key to its success and reputation in Zambia, according to Hercilus Harmse, Engineering Services Executive at Cementation Africa. He points to southern African projects such as the 1,200 m shaft at Palabora Mining Company – safely reaching its final depth in 2024 – and the 2,750 m ventilation shaft at South Deep.
“Many of our projects are conducted in environments where there are poor ground conditions or where extensive de-stressing of rock is required,” Harmse says. “We bring this experience into our designs and execution ensuring that we can apply innovative solutions – using our fleet of specialised equipment for rigging, winding and shaft sinking.”
Safety remains a cornerstone of Cementation Africa’s reputation in Zambia and globally, highlights New Business Director Graham Chamberlain. Over the last 12 years of shaft sinking and mine development, the company has achieved over eight million fatality free shafts.
“This is the result of consciously building a safety culture on every site and prioritising safety in all our planning and design work, using industry experience to learn from every incident,” Chamberlain says. “Particularly with equipment that is critical to safe operations, we develop and apply duplicate systems so there is always a backup. With winders, for instance, we ensure that an electronic system will be duplicated by a mechanical system in case of failure.”
Adendorff notes that, while technical capability and experience have made Cementation Africa the preferred contractor in its field in Zambia, the company has also made an important community contribution through its long presence in the country. This includes the building of a school for the deaf in 2016 – which today caters to over 100 children – and an orphanage feeding scheme.
“Our history in Zambia has also made us an employer of choice, as everyone knows our value system and the respect with which we treat our employees,” he concludes.