PROCESS FOR PRODUCING DIRECT REDUCED IRON (DRI) UTILIZING GASES DERIVED FROM COAL

摘要

A process for producing direct reduced iron (DRI) from iron ores, utilizing a gas produced from fossil fuels, particularly coal, containing sulfur compounds and BTX, wherein said gas is heated in a gas heater, preferably of the regenerative type, wherein heat is transferred from a previously-heated solid material to the gas produced from coal. The hot gas is caused to flow through a bed of DRI particles, iron oxides or other equivalent material, outside of the reduction reactor, where said material adsorbs sulfur compounds and the BTX are destroyed. The gas resulting from this treatment, free from sulfur compounds and BTX, is combined with a reducing gas stream withdrawn from the reduction reactor after H2O and CO2 have at least partially have been removed for regenerating its reducing potential, with or without undergoing a previous cleaning treatment, is used for producing DRI. One of the embodiments of the invention comprises producing DRI at high temperature with the advantage of higher productivity and energy savings when using said hot DRI in an electric arc furnace for steelmaking lowering the capital and operation costs of steelmaking.

主权项

1. A direct reduction process for producing direct reduced iron (DRI) from particulate iron ores in the form of lumps, pellets or mixtures thereof, utilizing reducing gases produced from solid or liquid fossil fuels, in a reduction reactor having a reduction zone where the particles of iron ore are caused to react with a reducing gas fed to said reduction zone at a temperature in the range from 750° C. to 1100° C., characterized by: heating a first gas stream derived from coal at a temperature between 650° C. and 800° C., causing said hot gas derived from coal to flow into contact with a bed of particles of a material adsorbent of sulfur compounds, outside of said reduction reactor, to form a second gas stream; combining said second gas stream with a third gas stream withdrawn from said reduction reactor from which H2O and CO2 have at least partially been removed for regenerating its reducing potential, forming a fourth gas stream; and feeding said fourth gas stream to said reduction zone of the reduction reactor.