With South Africa now working hard to contain the cost of its coal-fired power generation, efficiencies are vital throughout the value chain – not least in beneficiation.
According to Johannes Kottman, MBE Minerals SA managing director this means that the continuous improvement in coal beneficiation technology and regular equipment upgrades in plants will become more important. With more than a century of experience in the coal sector, MBE Minerals SA has built up a wide footprint of vibrating screens in Africa for sizing, scalping, dewatering and media recovery. It also provides destoning solutions to customers.
“Among the company’s innovations is the side plate mounted drive, a much lighter option to using vibrator motors,” says Kottmann. “The screens can also be supplied with vibrator motors if necessary, while resonance screens offer the added benefit of lower power consumption.”
All types of screening surfaces can be accommodated, with each screen incorporating mechanical design features such as vibration dampening, side plates, cross members and the appropriate feed and discharge chutes.
He highlights that MBE Minerals is actively engaged with developments in coal beneficiation technology through its international network, including the MBE Coal and Minerals’ Research and Development Centre in Cologne, Germany.
“This centre consults with customers globally in terms of optimum processing solutions, with the support of an in-house laboratory and pilot test work facilities,” he says. The centre also offers customer training, which can range from general mineral processing to maintenance of MBE Minerals’ equipment.
In addition to designing, engineering and supplying equipment, MBE Minerals conducts projects on a turnkey or EPC basis, he notes; the company can also operate complete coal processing plants. It is particularly well known for its Batac jig technology, which delivers high separation efficiencies and improved product quality, as well as high availability and throughput. This technology’s ease of operation, robust design and economical maintenance cost have also been important factors in its success.
The company developed the Batac jig to overcome the limitations of early stratification technologies, which achieved separation either by moving the entire jigging bed screen or through water pulsation generated in an air chamber beside the jigging bed.
“The separation accuracy of Batac jigs is due to electronic control of the air pulse generator and sensing of the thickness and densities of the material layers being separated,” he says. The under-bed pulsated Batac jig has proved ideal for coarse applications from 150 mm down to fine coal in the 10 to 0.5mm size range, with throughput rates of between 100 and 1 200 tonnes per hour (tph).
MBE Minerals has also developed a reliable and economical solution in destoning raw coal – the Romjig – which has produced impressive results in extensive testing around the world. “It achieves an overall reduction in the stone handled, says Kottmann, and there are indications of a lower percentage of refuse in the washery feed.
“This allows costs to be saved in a number of areas, such as reduced wear on machinery and transporting equipment, less grain degradation, and less dust and slurry,” he says. “It also means that flocculation consumption is reduced, along with flotation agents in downstream fines recovery circuits.”
The range of vibrating screens manufactured by the company includes dimensions up to 3.6m in width and 6.75m in length; they come in single or double deck configuration and with either circular or linear motion. They have been operating in the African mining industry for the past 40 years.
“We ensure that each application, whether greenfields or brownfields, is carefully assessed in conjunction with the customer, during a comprehensive engagement process to determine the optimum solution,” he says. Services available include detailed engineering, feasibility studies, raw material testing, financing concepts, erection and commissioning.
Components – as well as automation and process control equipment – can be supplied and installed for complete plants and systems. Measures to modernise plants or improve capacity can also be proposed. The company’s scope of services includes personnel training, along with pre- and after-sales services and support.