Mountains of ash from our coal burning power stations can be avoided if new uses can be found to convert it from waste product to a valuable commodity.
Already some of the ash is making its way into the country’s cement products to lend strength and aid curing of concrete, as well as having applications in agriculture, ground stabilisation and other uses. But the combined offtake of these is below 7% of the ash produced and needs to be boosted considerably higher to 18% if environmental goals are to be met.
For some time now, the South African Coal Ash Association (SACAA), has been working with Government, environmental agencies and business to develop solutions to growing ash dumps. Simultaneously, the aim is to alleviated other social or economic issues affecting the population which, if successful, can have positive and far-reaching benefits.
Take the challenge
At a recent fact-finding tour of the Matimba and new Medupi power station, SACAA general manager, Mark Hunter, revealed that research is underway to determine the viability of treating the scourge of acid mine drainage throughout the gold mining areas known as the Reef with suitable coal ash. Certain building products made with ash are also being tested and reviewed for suitability to alleviate housing shortages.
“However, these are not new ideas and we believe that a myriad of other uses exists for this waste product. There are certainly more uses in civil engineering for roads, concrete structures etc, as well as uses in manufacturing, chemical industries, landscaping and other uses. All one must do is look at the amazing composition and structure of different types of ash produced in each power station, from fine and potentially valuable fly-ash, to course bottom ash and everything in between.
“We simply need to challenge our technical brains-trust to look for applications in their fields of work or study and to find ways of overcoming challenges to integrate ash into their supply chains. And, for those who think that it is an impossible challenge, it is worth noting that certain countries in developed economies are using as much as 80% of their ash produced,” Mark says.
It is worth noting that South African fly ash and ash products were used to enhance concrete used to build the world’s then tallest building, the Burj Khalifa, as well as improving concrete used to construct the Katse Dam, South Africa’s highest, deepest and one of the largest water storage dams, as well as the architecturally superb Maputo Bridge in Mozambique.
This proves its worth and shows that with a bit of willpower and innovation, South Africa’s powerful business and technical sectors have the ability to solve the growing ash dilemma while at the same time using the free resource to overcome some of the biggest challenges of the current generation.
SACAA has recently joined forces with the large surface mining industry association, Aspasa, to improve its reach to a similar and broader cross-section of industries.