Process for calcining an ore-based material

A process for calcining an ore-based material comprising the steps:

• passing the material through a precalcination device equipped with at least one fuel injector to produce at least partially calcined material;
• supplying the at least one fuel injector of the precalcination device with at least one fuel so as to form a fuel-injection zone at the outlet of the at least one fuel injector;
• supplying the at least one fuel injector of the precalcination device with oxidizing agent comprising the products of combustion from a rotary kiln located downstream of the precalcination device with respect to the direction in which the material flows;
• thereafter passing the at least partially calcined material into the rotary kiln, the rotary kiln including a primary combustion unit at a downstream end of the rotary kiln;
• injecting at least one oxygen-rich fluid near to the fuel-injection zone, the oxygen-rich fluid having an oxygen concentration by volume that is higher than that of the products of combustion from the rotary kiln which pass through the precalcination device so that the oxygen-rich fluid supplies from 1% to 40% of the stoichiometric amount of oxygen needed for the combustion of the fuel injected by the fuel injector.