The Civil Engineering Contractor April 2019 | Page 17

ON SITE shareholder is a private equity fund out of Luxembourg. Upgrading fluorspar According to Wagner, the Nokeng project revolves around mining and the upgrading of fluorspar. Fluorspar is the commercial name for calcium fluoride, which is an industrial mineral that has multiple uses in our everyday lives. Nokeng Fluorspar Mine has two primary ore bodies: Plattekop and Outwash Fan, which will be mined as two different open pits. The ore is drilled, blasted, loaded, and hauled from the pits to the mineral processing facility. Construction of the plant started on 9 June 2017 and is well advanced. Wagner says that the initial steps in the commissioning of the plant started in early September 2018, with installation and commissioning planned to be completed by the end of February 2019. Nokeng Fluorspar Mine is a R1.9-billion project expected to start production in the first quarter of 2019. www.civilsonline.co.za Conveyor takes crushed material to the covered stockpile. “We have appointed a joint venture between Group Five and DRA for the construction of the plant, which they are doing on an engineering, procurement and construction (EPC) basis. They are responsible for the design, supply, construction, and commissioning of the plant,” Wagner explained. He noted that in a market where many civil engineering contractors are struggling to find work, “these sorts of partnerships work well for both parties [Group Five and DRA].” The processing cycle at Nokeng Fluorspar Mine starts with primary crushing (jaw-crusher), followed by secondary crushing (cone-crusher). High-pressure grinding rolls (HPGR) are used as the tertiary step, which reduces the ore to minus 6mm. Material is subsequently fed into a primary mill, where the material is further reduced in size to a P80 of 150 microns. Nokeng Mine has also installed four boilers, each with a rated capacity of 10 tonnes per hour. The plan is to have three boilers fully operational at any given time, with the fourth boiler on standby. Scope of work The scope of work for the Nokeng Mine included the building of an opencast mine (with two open pits), a tailings dam facility, and upgrading the surrounding infrastructure. This included installation of a 14km 132kV power line to the site, done as a self-build contract for Eskom (according to Eskom’s designs and specifications). This power line was commissioned and accepted by Eskom and is already connected to the Eskom grid — only the third of its kind in South Africa. The R80- million cost of this infrastructure, now owned by Eskom, was paid for by SepFluor. “The total direct capital cost amounts to R1.2-billion,” said CEC April 2019 | 15