Coal power by-product could benefit environment, building sector

UWC Professor Leslie Petrik says they have been able to create geopolymers that are extremely strong and can be used for building.

Some of the geopolymer products created from coal ash. Picture: Monique Mortlock/EWN

CAPE TOWN – Ground-breaking research into a coal power by-product could benefit the environment and the construction sector.

University of the Western Cape (UWC) and Cape Peninsula University Technology (CPUT) researchers on the Environmental and Nano Science Research Group believe they are close to being able to turn coal ash into cost-effective building material.

In 2009, Eskom reported that 37 million tonnes of fly ash was generated at power stations across South Africa.

UWC Professor Leslie Petrik says that they have been able to create geopolymers that are extremely strong and can be used for building.

Some of the geopolymer products created from coal ash. Picture: Monique Mortlock/EWN

“Success is that we’ve made geopolymers that are really light, so they can replace concrete, which means that you don’t need to go and add cement and that saves on CO2 emissions.”

She says the material can only be manufactured on a large scale once an investor is found.

Petrik adds they have also found that fly ash can be used in other ways like treating acid mine drainage.

“There are several aspects where fly ash can be used. It definitely can be used where the mining sector can treat their water.”

By 2020, policies around the removal of coal ash will change and Eskom will need to rethink how to get rid of it.