The
Bulk Flotation flowsheet, which is already in the Base Case, will be pilot tested over the coming months in order to fully de-risk it.
Following grinding, the process flowsheet incorporates conventional
bulk flotation including rougher flotation followed by two stages of cleaning to produce a gold-bearing sulphide concentrate representing about 3.5% of the fresh feed weight.
The overarching goal of this work was to test the possibility of replacing sodium cyanide by chitosan polymer as a selective pyrite depressant in the
bulk flotation of complex sulfide ore sample containing galena (PbS), chalcopyrite (CuFe[S.sub.2]), sphalerite (ZnS), pyrite (Fe[S.sub.2]), dolomite (CaMg[(C[O.sub.3]).sub.2]), and marcasite (a polymorph of pyrite).
Extremely fine intergrowth between galena and sphalerite minerals inhibits selective flotation separation and favours
bulk flotation. Due to fine dissemination and interlocking of minerals, extensive fine grinding is often needed, which is energy intensive.
Bench scale testing has been largely completed and testing moved on to
bulk flotation trails.
This collector has found application in the
bulk flotation of copper and cobalt minerals in conjunction with other thiol collectors, usually at slightly lower than pH than other common thiol collectors.
It is usual when moving from bench-scale to
bulk flotation that there is a drop-off in performance both in terms of the grade of the concentrates and the recovery of graphite.
PPL's expanded plant, simply put, now consists of a new circuit that is essentially a pebble flotation circuit and the old circuit, which is a
bulk flotation circuit.
* At a number of concentrators, new effective reagent regimes have been introduced for the separation of
bulk flotation concentrates, plant operation now incorporating full water recycling.