Study on replacing Jwaneng's main diamond-treatment
plant
Debswana Diamond Company (Pty) Ltd (DEBSWANA) has awarded Bateman
Engineering a fixed-price contract for a pre-feasibility study on
the replacement of the main treatment plant at their Jwaneng mine,
approximately 170 km west of Gaborone, in the Naledi river valley
of the Kalahari, Botswana.
DEBSWANA is the world's largest producer of diamonds by value with
Jwaneng mine, established in 1982, being the richest diamond mine
in the world, producing approximately 10 % of the world's diamonds
by value.
Jwaneng is an open-pit operation and the existing treatment plant
at the edge of the pit has to be relocated to permit continued expansion.
Also, as mining progresses, the kimberlite from increasing depths
is becoming more competent and is detrimentally affecting the processing
efficiency and thus the throughput at the plant. As a result, the
intention is to replace the main treatment plant rather than merely
move it. The existing completely-automated recovery plant (CARP) and
fully-integrated sort house (FISH) will be retained, however.
The objective of the study will be to compare the flow sheets of
a conventional ore-preparation route, comprising primary, secondary
and tertiary crushing, scrubbing and screening; an autogenous-milling
route; and a hybrid of conventional and autogenous milling. Trade-off
studies will be conducted on the estimated capital and operational
costs, processing efficiencies and the risks associated with the respective
routes. Three-dimensional computer models of the three flowsheet options
will be produced.
The cost of the three flowsheet options will be costed to a Class
1 accuracy (i.e. an accuracy of between -15 % +25 %).
The study report will be used by DEBSWANA in deciding on the appropriate
flowsheet to be used for the replacement plant, which could cost an
estimated $300 million. The selected flowsheet will be engineered
and costed in a feasibility study planned for early 2007.
Bateman Engineering has a good diamond-project track record in Botswana
that commenced in the 1980s. This includes a semi-mobile in-pit crusher
that was supplied to Jwaneng in 1995 and a green-fields processing
plant for DEBSWANA's Damtshaa mine in 2002. Currently Bateman Engineering
is engaged in doubling the throughput at the Damtshaa mine.
Bateman Engineering was selected for its diamond-processing capability,
coupled with its extensive study and project-execution track record
and its ongoing commitment to assist in the development of the skills
base in Botswana (see BATEMAN Globe, Nos 39 and 51).
The tender for the study was submitted through Bateman Botswana,
jointly held by Bateman Projects Botswana and Botswanan citizen companies.
The contract was awarded in January 2006 and completion is scheduled
for the end of the year. The work will be done by an integrated DEBSWANA-Bateman
Engineering team.
More information about this pre-feasibility study may be obtained
from
James Nieuwenhuys, General Manager, Diamonds or Graham Joyce, Project
Manager on +27-11-899-9111 or Mokenti Raborokgwe, Botswana Country
Manager on +267-316-7873 or
email Diamonds@BatemanEngineering.com.
