RO127756A8 - Cylindrical multi-hollow briquette produced of ferrous pulverous and small waste with a grain size of less than 2 mm - Google Patents

Abstract

The invention relates to a cylindrical multi-hollow briquette obtained from ferrous pulverous and small waste with a grain size of less than 2 mm, said briquette being used in ferrous metallurgy in the wind furnaces producing the refining iron or in the installations for direct reduction of iron in order to produce iron sponge. According to the invention the briquette (1) has the shape of a cylinder with a height h=40...50 mm and an outer diameter D= 70 mm, in which there were cut 7 identical tubular cavities with internal diameters d= 10 mm, placed as follows: one central cavity and six cavities whose centres are at a distance R= 20 mm in relation to the centre of the briquette (1) and at 60° to one another and it is obtained by hydraulically pressing, in a mould, a mixture having the following composition: 40...60% steel plant dust, 8...10 % furnace dust, 8...10% furnace agglomeration sludge, 5...7% iron scale sludge or iron scale with a grain size of less than 2 mm, 5...7% coal dust, 5...7% ferrous fraction of less than 2 mm of steel plant slag, 3...5% graphite, 3...5% ferro-basic concentrate obtained from steel-ore waste with grain size of less than 2 mm, 2...4% bentonite, 2...4% lime, 4...8% water, the briquette (1) showing an increase of the surface of the reaction front by 42.85% and, by the existence of the 7 cylindrical interval surfaces (3) outside the outer cylindrical surface (2), determining an increase of the reduction speed by up to 76% in relation to the common briquettes.