Modern Mining January 2017

GOLD

handle 4 000 tonnes per day of mate- rial and our crushing capability now comfortably exceeds mill capacity.” With Phase 1 beating its targets and generating revenue, Asanko Gold was able to announce in early November that it would proceed with the Phase 2A expansion, which has an estimated capital cost of circa US$125 million. Phase 2A envisions the start-up of mining operations at Esaase, the construction of a 27 km overland con- veyor to link Esaase and the Obotan (Nkran) facilities and the expansion of the existing Phase 1 processing plant at Obotan from 3,6 Mt/a to 5 Mt/a to produce approximately 300 000 ounces of gold in 2018. The upgraded plant will process a blend

designed to reduce spillage. The system will be equipped with an ST2400 belt with a width of 800 mm – with a total mass of 1 305 tonnes – and have an installed power of 2 800 kW. Says Truter: “The conveyor will be able to transport up to 1 200 t/h of ore which is suffi- cient for Phases 2A and B although only 680 t/h will be required in Phase 2A. We anticipate commissioning in Q2 2018.” DRA has been appointed as the EPCM contractor for Phase 2A while the FEED con- tract for the conveyor has been awarded to ELB Engineering, which recently completed the nearly 27 km long, 2 800 t/h Impumelelo overland conveyor for Sasol Mining in South Africa. Based on present planning, implementa- tion of Phase 2B – estimated to cost between US$210 and US$220 million – will follow hard on the heels on Phase 2A. This phase will further expand the Obotan processing facility with the construction of an additional 5 Mt/a CIL circuit for a total processing capacity of 10 Mt/a (3 Mt/a from Nkran and its satellite pits and 7 Mt/a from Esaase). “An interesting point is that it was originally

of approximately 2 Mt/a of ore from Esaase and 3 Mt/a of ore from the Nkran pit and surround- ing satellite deposits. Looking at the Phase 2A scope in more detail, Truter says that the plant upgrade – which is scheduled for commissioning in Q1 2018 – requires only relatively minor capital works. “We’re going to be increasing the capac- ity of the mill discharge pumps, changing the internals of the existing cyclone pack, adding two Knelson gravity gold concentrators and installing an additional Gekko intensive leach reactor,” he elaborates. “We will also increase gold room capacity and the capacity of the tail- ings pumping system. “At Esaase, where we will eventually have three pits, we will first establish the South pit, with a view to start mining operations in Q2 2018. The other pits are the Main pit, which will go down to approximately 400 m and which hosts the bulk of the resource, and the small North pit. As at Nkran, the mining will be a standard truck-and-shovel operation undertaken by a contract miner, with around 14 Cat 777 trucks – or equivalents – being deployed initially. Infrastructure at Esaase will include primary and secondary crushing facilities.”

Layout of the Esaase mining operation.

Asanko Gold Mine – a thoroughly Ghanaian operation Asanko Gold Mine currently employs approximately 1 700 people (including contrac- tors), the vast majority of them (97 %) being Ghanaian nationals, with 44 % of them coming from local communities. Asanko Gold in Ghana is headed by MD Joe Zvaipa – who is a Zimbabwean – with Charles Amoah, previously the Met Manager (and acting GM) of Gold Fields’ Damang Mine, as the General Manager. Says Hugo Truter: “The skills base in Ghana, developed in over 100 years of com- mercial gold mining, is such that we have little need to bring in expatriates. We do provide some high level support to the mine from our office in Johannesburg but Asanko Gold Mine is essentially an operation managed and manned by Ghanaians.” 

The biggest single component of Phase 2A will be the overland con- veyor which, at just over 27 km long, will certainly rank as the longest single flight conveyor in Africa and possibly in the world. Although it tra- verses largely flat terrain, there will be 10 public road crossings, 27 pedes- trian crossings and two haul road crossings. It will feature HDPE idlers for reduced noise and friction and is

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