Veolia Ghana, a subsidiary of the French giant Veolia, specialised in wastewater and waste treatment as well as energy production, has recently won a 3-year contract for the treatment of wastewater from the Obuasi gold mine. Located near Kumasi, in southern Ghana, the mine is operated by the South African company AngloGold Ashanti.
Veolia Ghana, a subsidiary of the French company Veolia, has been selected to manage the water at the Obuasi gold mine, a locality located more than 60 km from Kumasi in southern Ghana. The open pit (and underground) gold mine is operated by the major South African mining company AngloGold Ashanti.
Water is an essential resource for mining, and in particular for gold. Another characteristic of a facility like the one in Obuasi is that water is used directly to process gold ore. In concrete terms, the latter contains other chemical compounds that must be separated from gold. After fine grinding, it is then soaked in an aqueous cyanide solution. The gold contained in the ore dissolves and forms aurocyanide complexes. The gold is then recovered in metallic form by electrolysis. Then the residual solution has to be treated, because cyanide is a very dangerous product for health.
In addition, the water is also used to transport sludge from dredging, or simply for dust removal. On the other hand, water management also includes the control of rainwater that can cause (if not carefully considered) flooding of facilities and untreated releases to the environment in this tropical climate, which is prone to high seasonal rainfall.
Operation and maintenance of the installations
Veolia Ghana’s new three-year contract covers the operation and maintenance of the facilities. They include four wastewater treatment plants and two drinking water treatment plants for employees of the mine. “As a major water consumer, the mining sector is one of the major growth areas identified by Veolia. The group works hand in hand with industry stakeholders to find solutions to the challenges they face in Africa, as elsewhere in the world. This is a strategic market segment with promising growth prospects for the group,” says Veolia.
In addition, the French giant specialising in water and waste treatment and electricity production is well acquainted with the mining sector. “This new contract confirms Veolia’s operational expertise in the treatment of water and waste from mining industries (…) By optimising the wastewater treatment process at the Obuasi gold mine, we have the opportunity to improve the productivity of this crucial operation,” explains Christophe Maquet, Veolia’s Africa and Middle East Area Director.
The company, which employs more than 171,000 people worldwide, is not in its first collaboration with South African giant AngloGold Ashanti in Ghana. In 2014, Veolia Ghana was awarded a contract to operate and maintain the water treatment plant for the Iduapriem open-pit gold mine in the western part of the country. The mine is wholly owned by AngloGold Ashanti.
Jean Marie Takouleu