/ 4 July 2014

Developing wastewater treatment

Water.
The Blue, Green and No Drop certification programmes are the department’s regulatory mechanisms to improve municipal drinking water quality, wastewater management, water conservation and demand management.

The National Research Foundation’s (NRF) South African Research Chairs Initiative (SARChI) is making an important contribution to the country’s pursuit of solutions that address the delivery of water to urban and rural communities. 

Professor Thalappil Pradeep of the Indian Institute of Technology Madras has been working on nanoscience solutions for the past 12 years as a means to remove pesticides from ground water. 

His involvement as a Research Chairs follows the invitation from the University of Johannesburg (UJ) to help further the study of nanoscience in the treatment of contaminated water. He explains that this work is ongoing, with the objective of establishing a thematic centre focused on developing nanomaterials for the treatment of water. 

Much of this work is in exploring a process known as reductive dehalogenation that aims to break down contaminants at a molecular level. This contamination of water is often the result of using pesticides.

International experience

His Chair at UJ aims to extend the work he has done in India, with a key outcome being the creation of a nano-technology centre that can continue this type of research into the future. 

He believes that technology relevant to South Africa’s water contamination challenges can be developed in the next five or so years.

Another international researcher who is applying his expertise locally is Sweden’s Professor Thor Stenström who is currently affiliated to the Durban University of Technology’s (DUT)’s Institute for Water and Wastewater Technology.

His Research Chair in Development and Optimisation of Wastewater Treatment Technology for Developing Economies, is focused on improving the understanding of microbial action in full-scale biological wastewater treatment facilities.

He explains that the research projects aim to present a multi-barrier approach to treatment processes that reduce the environmental and human risks from wastewater. To this end, he is looking at developing and adapting low-cost alternative wastewater treatment technologies, for both rural and peri-urban areas, which relates largely to the use of biotechnologies in the treatment process.

His work is also looking at catchment areas, specifically the Umgeni catchment area, including disaster risks due to events such as flooding.

He explains that he is still in the formative stages of his Research Chair because he was appointed into the position in 2013 and he is establishing relations and collaboration with local councils and bodies such as the Umgeni Catchment Authority, other universities as well as faculties at DUT.

Although on a different scale, his work is related to that being done by Professor Maggy Momba of the Tshwane University of Technology who is exploring water quality and wastewater management at a local community level.

She explains that her main areas of focus are to reduce the cost of the treatment of drinking water, the control, prevention and treatment of water-borne diseases and the development of effective water management strategies. Hers is also one of the Chairs awarded in 2012.

Simple solutions

This work has already made an impact in the form of affordable solutions for rural communities using simple, but effective microbiology and biotechnology solutions. 

She and her team have thus far developed prototypes that are being tested in the village of Makwane in Limpopo. 

These simple solutions consist of household drinking water filtration systems — one based on silver-impregnated porous material and the other using a biosand zeolite silver impregnated clay granular — that could help communities treat drinking water for around R250 per filter that could be effective for up to three years. 

The last of the four Research Chairs, looking into water treatment technologies, is headed by Professor Christian Wolkersdorfer at the Tshwane University of Technology. His research focus area is one that is of huge concern locally, but not unique to South Africa in that it is concerned with mine water drainage.

His is one of the new Chairs so has not yet made substantial progress, but is actively working with the eMalahleni municipality to explore the best combination of technologies to treat mine water drainage.

Wolkersdorfer also has a Research Chair in Finland where the use of nanotechnology is being explored as one possible treatment method. 

He intends bringing some of that knowledge and technology to South Africa, as well as establishing a centre locally that would focus on the challenges posed by mine water drainage.

This supplement has been paid for by Department of Science and Technology and its contents signed off by the DST and the National Research Foundation.