various processes have been established for extraction of
nickel from lateritic ore. The hydrometallurgical routes are applicable to ore
bearing nickel 2% depending on the content of nickel and gangue as well. In
this paper, an attempt has been made to produce nickel enriched nugget from a
mechanical mixture and a low grade nickel ore, using carbon as reductant in the
presence of alkali chloride and sulphur. Experiments were carried out in 100gm
scale with the mechanical mixture of pure nickel and iron sulphate and also
with laterite ore samples. The raw materials used in the study, were dried at
1100C before mixing with carbon, alkali chloride and sulphur. The charge mix
was transformed to a graphite crucible and roasted in a furnace at a predetermined
temperature. After the reaction, the roasted mass was discharged in hot
condition. It is observed that, the molten phase is separated from the gangue
in the form of nugget at the bottom of the crucible. Role of alkali chlorides,
carbon, sulphur, time of roasting and roasting temperature has been
investigated during the study. The XRD, EPDX and microscopic analysis of the
sample indicates that Ni, NiS are the major mineral phases present in the
nugget along with Ni3S4 and Ni3C as minor phases. An effort has been made for
the enrichment of nickel using lateritic ore of Sukinda. It is observed that
there is no clear cut separation of liquid mass from the ore charge. This may
be due to the gangue minerals like silica, magnesium, calcium etc., present in the
ore. Studies have further being carried out to establish the role of other
minerals during the formation of nickel enriched nugget.