Operation and performance of the Sishen jig plant
HA Myburgh, A Nortje
Sishen Iron Ore Mine previously used only A-grade material (>60% Fe in
situ value) from the pit for beneficiating in the DMS plant to a final product
grade of 66% Fe in lump and 65% Fe fine ore. The B-grade (between 50%
and 60% Fe) and C-grade material (between 35% and 50% Fe) were
stockpiled separately, owing to the inability of the existing DMS plant to
beneficiate material at densities higher than 3600 kg/m3. The ability to
beneficiate the B-grade material at densities higher than 3600 kg/m3 was
evaluated, and air-pulsed jigs were found to be techno-economically
feasible and value maximizing.
The beneficiation of B-grade material would add to the existing DMS
production of 28 Mt/a, with no additional mining cost and only limited
costs for the handling of waste and B-material. The objective of the Sishen
Expansion Project (SEP), i.e. the jig plant, was to produce 10 Mt/a of
saleable product with six modules to the set physical and chemical specifications
by 2009. During the start of construction, it was decided to add
another two jig modules to the plant to increase production to 13 Mt/a.
During commissioning and ramp-up the shortcomings and advantages
of the jigs were fully experienced and understood, resulting in many
changes to optimize jigging performance.
Keywords: jigging, jig efficiency, jig control, physical separation, process optimization.