55 / 84
January 2017
MODERN MINING
53
Top projects
GOLD
Layout of the Esaase mining
operation.
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
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.”
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
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
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.”