GB1282150A - Agglomeration of reduced iron ore - Google Patents

Abstract

1282150 Agglomerating reduced iron ore particles ESSO RESEARCH & ENG CO 2 Dec 1969 [11 Dec 1968] 58807/69 Heading C1A [Also in Division C7] Reduced iron ore particles are agglomerated by feeding into a fluidized bed thereof, particles of reduced iron ore of sizes ranging from 1 to 10,000 microns and averaging 50-400 microns, a substantial proportion of which are less than 325 Tayler Mesh size, introducing a heavy liquid hydrocarbon having a Bouradson carbon residue above 10% by weight, maintaining the particles at temperatures ranging from 850‹-1100‹ F. for a time sufficient to partially crack said hydrocarbon and deposit coke on the very fine particles thereby cementing them together to form particles larger than 325 mesh size. The bed may be fluidized with a non-oxidizing gas (e.g. N 2 or steam) at a superficial gas velocity of 0À3-1À5 ft./sec. or alternatively with a reducing gas. The hydrocarbon is preferably sprayed on to the top of the bed in droplets of size ranging from 1/10 size of the largest particle to be agglomerated to 10 times the size of the average particle in the bed. Residence times in the bed may be from 10-60 minutes. Preferably 0À1-1À0 part by weight hydrocarbon are used per hour per part of metal particles in the bed. The prior reduction of the ore is described (see Division C7) yielding typically reduced ore containing 90% Fe and 5% FeO. The ore may be fed to the fluidized bed in a hydrocarbon suspension formed by scrubbing the off gases from a reduction process.