Feasibility of horizontal-belt filtration at
Rössing Uranium
A feasibility study for installing a horizontal-belt-
filter system at Rössing Uranium Ltd is being executed by Tawana
Projects (Pty) Ltd, a joint- venture company between BATEMAN and PRO
PLANT (Pro Plant Engineering Design (Pty) Ltd).
Rössing, a large open-pit uranium mine, is situated
in Namibia, south-western Africa, lying 65 km inland from the coastal
town of Swakopmund in the Namib Desert. It is one of the largest open-cast
uranium mines in the world and, with solid reserves, will continue to
serve the world energy industry. Rössing is part of the Rio Tinto
group of companies, which currently holds 68,6 % of its equity.
The horizontal-belt-filter system is being proposed
as a significantly more efficient method of separating the uranium-bearing
solution from the sands and slimes pulp than the system presently employed.
The existing system consists of rotoscoops, which are used in combination
with a washing process and a thickening circuit. The current process
is complex and results in the loss of substantial amounts of soluble
uranium and other valuable elements such as acid and iron.
Hydrocyclones are used to split leach pulp into sands
and slimes fractions, which are gravity fed from the leach discharge
tanks. The two fractions enter separate washing circuits, with the sands
fraction passing through a set of rotoscoops, while the slimes are washed
through a five-stage counter-current thickening system. The coarse fraction
is conveyed to the tailings dam and the fines are pumped. At the tailings
dam the two fractions are combined. This system requires considerable
maintenance and is costly to operate.
It is envisaged that, by introducing the horizontal-belt-filter
system into the metallurgical process, the two fractions will be combined
before being washed and dewatered, on the filters. The increased washing
efficiency of the belt filters is expected to minimise the uranium,
iron and sulphuric-acid losses.
The filtrate will then follow the conventional process
flow to the CIX plant and the dry filter cake will be transported via
the conveyor system to be finally deposited on the tailings dam.
For further information, please contact:
Gordon Sneddon, Engineering Manager,
Tawana Projects (Pty) Ltd, on +27-11-899-2217 or
email tawana@batemanengineering.com
or
Johan Verster, Process Manager,
Tawana Projects (Pty) Ltd, on +27-11-899-2461 or
email tawana@batemanengineering.com
VIEW
PDF
