South Africa’s coal mining landscape is at present driven largely by the domestic market and remains responsible for generating the majority of the country’s energy requirements.
While roughly 80% of total supply is produced by just five major mining houses, the rise of the junior industry is rapidly emerging as Eskom looks to new +50% BEE-compliant entrants to sustain coal production and demand going forward.
In 2016 the export market produced less revenue than South Africa’s domestic market - because the country remains so heavily reliant on coal to generate electricity.
“About 75% of all coal produced is consumed locally across our 17 operating power stations (soon to be 18 when Kusile comes on line) which are designed to process our relatively low grade, medium ash content coal,” outlines Kim Schoepflin, CEO of South Africa-based screening company Kwatani.
While the majors will continue to supply the majority of the power station coal for now, Eskom is looking to move away from its cost plus models which it has in place with these companies and is seeking to support the new junior market which will have the required black ownership in place.
“But Eskom needs about 100 Mtpa of coal and the current junior sector is in no position to meet this required tonnage – it does not have the economy of scale, nor does it have the resources to develop and operate new mines sustainably and cost effectively,” Schoepflin continues.
Consequently, it has become essential that original equipment manufacturers (OEMs) partner with these junior miners and use their expertise to help develop cost effective, fit-for-purpose processing solutions.
This will contribute towards growing this market segment.
“As our role in helping deliver sustainable operations increases within this sector in particular, OEMs also need to ensure that they are equally BEE compliant in order to contribute to legislative requirements and ensure miners meet their ownership quotas,” Schoepflin notes.
Kwatani has operated within South Africa’s coal sector for 41 years and has established a successful equipment supply track record with the country’s major coal miners.
It is has also made significant entry into the junior sector and as such has positioned itself as a screen supplier of choice for the coal industry, dedicated to delivering across three platforms:
Kwatani engineers specific solutions according to the needs of the customer, where he is in his operational lifespan and what purpose and function each screen needs to fulfil.
This can vary significantly between a small-scale miner and a long-life major and as such takes into account operating lifespan, type of product needed, processing requirements, tonnage and yield requirements, etc.
Further to this Kwatani also considers what skills and resources it can contribute towards delivering an ideal solution.
“We have in-house engineers and metallurgists who engage with the customer to establish what they need.
"This information is then disseminated to our mechanical design engineers who then design the equipment for a specific duty.
"We consider various factors that may affect the fatigue life of the screen in order to provide a durable, long-lasting screen.”
The use of in-house finite element analysis also enables Kwatani to tweak the screen in terms of design, size, and mass quickly and cost effectively and in so doing ultimately deliver a fit-for-purpose solution.
Because it works across the coal mining spectrum, Kwatani is equipped to understand the specific needs of the majors and the juniors and engineer a solution which caters to individual specific needs.
“In the current environment major coal miners are looking for large-scale equipment to boost their efficiency and throughputs. We offer a 4.3 m wide banana screen which is well suited to this requirement and was developed after fully assessing typical failure modes in existing equipment,” Schoepflin outlines.
Having focused on critical elements such as structural integrity, weight distribution and lifespan, Kwatani’s screen can withstand the highest tonnage in the heaviest-duty of applications.
Schoepflin also highlights the company’s use of circular cross members (the main structural elements of the screen holding the side plates together) as opposed to conventional H-beams which provides greater structural stability and allows an even distribution of stress around the circular section.
“Further to this we will also design our 4.3 m wide screen to fit into an existing footprint which can prove particularly challenging in large applications.”
The junior coal sector operates at the opposite end of the scale and typically requires smaller-scale, modular plants processing up to 250 tph, incorporating screening equipment below 2.4 m in width.
“Because these customers need to start generating revenue as quickly as possible, they operate on very tight delivery times.
"We are able to accommodate this thanks to a jobbing production system which allows us to manufacture multiple machine orders quickly without compromising on customisation.”
Schoepflin also highlights two screening products which Kwatani prides itself on in terms of delivering according to arduous conditions.
“We offer brute force grizzly feeders for run-of-mine operations which are capable of sizing and feeding material from the smallest fines fraction up to 350 mm (and often far larger as well) – operating at up to 2 000 tph.”
These highly specialised feeders comprise cast manganese bars which work harder over time to enhance durability.
The company’s galvanised vibrating screens are coated in zinc to prevent corrosion and also comprise rubber-lined cross members to provide additional wear protection which in turn increases the longevity of the screen.
“Regardless of who we are supplying to, Kwatani has the economies of scale to provide a cost effective product which because of its long-lasting design and build reduces the cost per ton which further reduces the overall cost of the machine as well.”
Considering screening equipment is a critical component of any coal plant, and can be the cause of an unscheduled plant shutdown if a failure occurs, regular maintenance is essential to prevent this while simultaneously also ensuring that equipment is being efficiently operated and maintained.
The lack of skills, compounded by the industry’s reactive nature, further necessitates the need for regular service programmes.
Kwatani offers customised service level agreements for the major coal miners which includes continuous audits at given time intervals to measure the performance and condition of the equipment, on-site training for artisans through to supervisors, on-going contractual training, on-site stock-holding management, refurbishment programmes as well as cost per ton multi-year agreements where Kwatani is fully responsible for equipment operations, replacements, refurbishments and maintenance.
“Junior mining houses do not require such extensive service level agreements but do however need regular visits and quick turnaround times on service calls to ensure they remain operational for as much time as possible.
"We are comfortable accommodating this need for this sector of the market and are financially flexible in finding the best option that suits the client’s pocket.”
Black ownership and BEE compliance is no longer new to the mining sector but adherence is becoming more prevalent.
Kwatani is a Level 4, 30% black owned business of which 11.25% is women owned.
“Importantly, we have established long-term partnerships with engineering and entrepreneurial black owned entities that not only have an understanding of our business, but also the mining industry, the coal sector and the emerging junior industry as well.
"Our board and shareholders are pleased with our progress in this regard and want to see the company continue along this transformation path,” concludes Schoepflin.
Feature image credit: Kwatani