BATEMAN pinned-bed clarifiers for Kansanshi
Copper, Zambia
As a result of the successful operation
of BATEMAN pinned-bed clarifiers at Bwana Mkubwa copper mine in Zambia,
an order was received for two units for the Kansanshi copper-gold
project, located some 15 km north of Solwezi in North Western Province,
Zambia.
The holding company, First Quantum Minerals Ltd,
which owns the Bwana Mkubwa mine, has an 80 % share in the Kansanshi
project with the remaining 20 % owned by Zambian Consolidated Copper
Mines (ZCCM).
The Kansanshi processing plant is being designed
by GRD Minproc Limited of Perth, Western Australia, and the contract
was awarded by their wholly-owned, Bryanston-based, South African
company GRD Minproc (Pty) Ltd. The contract covered the supply of
two 10 m-diameter BATEMAN pinned-bed clarifiers, and associated control
instrumentation. The clarifiers were delivered in March 2004, for
use for low- and high-grade clarification of the pregnant leach solution.
The clarified solution produced from the overflow of the counter-current
decantation circuit goes to the downstream solvent-extraction circuit,
which requires a clarified feed to minimise crud formation.
The units treat the low- and high-grade streams,
respectively, and handle a feed-rate of approximately 875 m³/h
of acidic copper-sulphate containing in the region of 200 ppm of suspended
solids. The overflow from the clarifiers is designed to contain only
20 to 50 ppm of solids.
The units were designed and fabricated in South
Africa, taking into account the fact that they would have to be transported
by GRD Minproc overland to Zambia in substantially assembled pieces,
where they were erected on site under BATEMAN supervision by a contractor
appointed by GRD Minproc. All wetted parts were fabricated from 316L
stainless steel to withstand the corrosive nature of the solution.
The BATEMAN pinned-bed clarifier was developed in
answer to a need for clarification systems which could consistently
meet the requirement of 50 ppm and less of suspended solids in solutions
supplied to solvent-extraction plants. The two 8 m-diameter BATEMAN
pinned-bed clarifiers at Bwana Mkubwa mine have been successfully
processing 420 m³/h of acidic copper-sulphate solution containing
up to 1 000 ppm of suspended solids, to produce a clarified solution
containing between 20 ppm and 50 ppm of suspended solids. When they
were commissioned in late 2002, they were the first to be used in
a large-scale operation in Africa.
For further information, please contact Craig Gilbert,
BATEMAN Manager, Processing Technologies, on +27-11-201-2300 or email
engtech@batemanengineering.com.
