Modern Mining November 2023

CONSULTING ENGINEERING AND PROJECT MANAGEMENT

WEC Projects to build water treatment plants for Côte D’Ivoire gold mine

South African EPC contractor specialising in water and sewage treatment plants, WEC Projects, has completed a contract for the design and engineering of three water treatment plants for Endeavour’s Lafigué Gold Mine situated about 120 kms northeast of Bouake in Côte d’Ivoire.

W EC has designed and built three water treat ment plants – one filtration unit for treating water used for processes, dust control, fire suppression and other applications at the mine, and two units for treating potable water to be used by the personnel at the mine and mine camp. The treatment plants will be fed raw water from vari ous boreholes at the mine. The filter water treatment plant is capable of processing up to 130 m 3 /hr of water and comprises two modified shipping containers; a 6 m container which will house the electrical controls and a 12 m container with four filter units, which measure 2.2 m in height and 1.8 m in diameter each, as well as the primary pump system and blower unit. Raw water is fed into the custom-built inlet floccu lation tank where it undergoes chemical coagulation to allow solids to settle. After the flocculation tank, the dosed water will enter a custom clarifier tank whereby lamella media will aid the settling process. From the clarifier, the water enters the break tank that supplies the filters. The system’s blower

Feed tank to supply softening process (PWTP). This is post-filtration through the sediment and granular activated carbon filters (shown in background – blue vessels). unit is for air scouring the filters, reducing the need for backwashing. The water passes through the filtra tion units and is distributed to the client/mine holding tanks. The filtration system uses specialised silica media and activated carbon media for the filtration process to remove solids and organic compounds. For potable water, the company designed and built two plants with processing capacities of 10 m 3 /h and 5 m 3 /h per day respectively and which will be used for drinking water at the mine and the mine camp. The systems will be installed in 12 m shipping containers and feature sophisticated filtration and treatment processes. Raw water is fed into the plant’s filtration section and filtered through acti vated carbon, which removes organic compounds and improves the taste and odour of the filtered water. The water is also softened using resin and salts, and is then remineralised. Chlorine hypochlorite and ultraviolet radiation is used for disinfection before the treated water is fed back to the mine and the mine camp. All three plants include motor control systems, human-machine interfaces and programmable logic controllers to ensure a high level of automation. The only human intervention required is to moni tor the processes from the control room and to add

Filter water treatment plant – clarifier on right and flocculation tank on left. Walkways and handrailing’s being checked for fitment before shipment to client.

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32  MODERN MINING  November 2023