A method for
selective reduction, simultaneous
drying and
dehydration, and electric furnace
smelting of ferronickel from
ferrosilicon-
magnesium laterite nickel ore is disclosed, belonging to the field of
mineral processing and metallurgical technology. The steps are as follows:
Ferrosilicon-
magnesium laterite nickel ore is crushed and placed in a
silo, then fed into a multi-stage
cyclone preheating and
drying system. Adsorbed water is removed by the preheated
airflow, followed by heating to remove
structural water, forming a dried material. The dried material undergoes gas-
solid separation to form a primary
solid material which enters the reduction reactor. High-temperature
flue gas is returned to the preheating and
drying system for further preheating and drying.
Nitrogen and
methane or
natural gas are introduced into the inlet of the reduction reactor, resulting in the outflow of reduced material. The secondary
solid material after gas-solid separation enters the
smelting reactor, with excess
methane returned to the main furnace for
combustion and heating. The secondary
solid material is mixed with flux to adjust the
silicon-
magnesium ratio before
smelting, followed by cooling to obtain ferronickel
alloy and
slag. This method solves the practical problems of
rotary kiln pre-reduction-electric furnace smelting processes, such as easy ring formation in the
rotary kiln, low operating efficiency, and high
power consumption.