Despite South Africa’s fast-track entrance into the renewable energy sector, the country’s reliance on coal to produce electricity will remain significant for decades to come.
The key to ensuring the industry’s successful longevity and sustainability however is dependent on the ability to break through processing barriers and improve the recovery of uneconomical, poor quality coal, writes Laura Cornish.
Research plays a pivotal role in solving the coal sector’s current and future challenges and one of the universities leading the way forward in doing so is South Africa’s North-West University. The tertiary learning institution, through its students’ masters’ degrees and doctorates, has become recognised for its forward-thinking concepts and ideas and ability to test new waters and make headway in solving industry challenges.
Mining Review Africa caught up with the North-West University’s associate professors Quentin Campbell and Marco le Roux at the 2015 Southern African Coal Processing Society biennial coal conference in Secunda to discuss the latest research advancements in the coal sector – which includes four exciting, industry breakthrough areas.
Liberating ‘unrecoverable’ coal
The majority of South Africa’s high (thermal) quality coal in the Witbank and Highveld coal fields is depleted and technological advances are required to improve the extraction of poorly liberated coal which cannot be recovered at significant yields at present.
“A lot of South and southern Africa’s unmined coal resources are geologically structured like bar codes,” says Campbell. “They comprise interspersed layers of good and poor quality coal. This is particularly typical in the Northern parts of the country and Botswana.”
Washing a combination of these layers (as a mixture), based on density, usually results in poor yields. “This problem can be solved by ‘breaking’ the coal open and exposing the valuable seams which in turn….