With water management becoming a national strategic issue, infrastructure development company the Aveng Group, through its water treatment specialist company Keyplan, is implementing solutions to help mitigate this impending crisis, while steadily positioning itself to become a significant player in the water treatment industry.
The Aveng Group's engineering & projects company GM for environmental services Harry Singleton notes that coal-mining major Anglo Coal's eMalahleni plant, near Witbank, has effectively been using Aveng's solutions since September 2007 to create high quality potable water from acid mine drainage (AMD) water, while Aveng is in the process of delivering a seawater desalination plant for French mining and energy company Areva, in the heart of the Namib desert. The company has also secured a small water treatment plant outside Adelaide, in Australia, for uranium exploration company Uranium One. Aveng sees a potential growth aspect in AMD and seawater desalination in Australia and is targeting that country vigorously.
"We believe that we have a technology and model that provides a solution to water treatment that is viable and proven," says Singleton.
The eMalahleni plant that was built for Anglo Coal was designed and built using Keyplan's in-house technology known as the HiPRO process, which uses reverse osmosis to reverse the damage done to the water through AMD. The plant has been producing high-quality potable water that goes from the plant with no further treatment into the eMalahleni municipal water system, meeting the South African National Standards (SANS) Class 1 standard, which is currently the highest drinking water specification in South Africa.
The plant, which produces 25 000 cubic metres a day, has a water recovery rate in excess of 99,7%. Singleton adds that the company is looking at ways to further reduce the brine and increase the recovery rate to 100%. He adds that based on this model Anglo Coal is considering extending the plant.
Keyplan is also building a second plant for local black-owned and controlled mining and exploration company Optimum Colliery. The plant is being commissioned and will produce potable water within the next two months.
"We are now in discussions with government to see how we can take what we have and introduce it into other areas, specifically in the gold mining regions where AMD is a serious problem," says Singleton.
Supportive of the AMD solution, Keyplan has also developed a sea water desalination solution that can be used to provide water to major towns, cities and mines along coastlines. Singleton explains that a plant that is currently being commissioned for Areva, in Namibia, has the capacity to desalinate and deliver 20-million cubic metres of water a year to the Trekkopje mine using an overland pipeline. This, he says, is the first large scale sea water desalination plant in Southern Africa and will go a long way to provide drinking water to the desert region of Namibia.
"We are currently in final negotiations with Areva to operate and maintain that plant for 12 years," he says.
He adds that, given the expected future demand of 45-million cubic metres of water a year, Keyplan was innovative in its design and has ensured that the Trekkopje plant's sea water intake system has a capacity to extract 360 000 m3 of water daily. Furthermore the plant has been designed so that it can be upgraded to double its capacity. The environmental impact assessment has been completed for the entire site, including the possible upgrade area.
"We see sea water desalination as a growth area in South Africa and we are in talks with the municipalities of Cape Town, Port Elizabeth and Durban for large desalination plants. A third area of growth is water reuse, which is the treating of water from sewage plants to potable water standards. We see that market in South Africa starting to gain momentum, the only question that remains is whether the population is ready to drink treated sewage water," concludes Singleton.