SU1618771A1 - Method of producing iron-ore pellets - Google Patents

Abstract

The invention relates to metal, lurgia, in particular to the production of iron ore pellets for blast-furnace smelting. The purpose of the invention is to increase the strength of the pellets. The treatment of lumpy materials is carried out with a stream of compressed air supplied in a cross-current to the Materials, and the charge is humidified in the range of 0.1–0.25% for every 100 m3 / h-t of compressed air. 1 hp f-ly, 2 tabl.

Description

This invention relates to metallurgy, in particular to the production of iron ore pellets for blast furnace smelting.

The purpose of the invention is to increase the strength of the pellets.

Example. The method of obtaining pellets is carried out on a laboratory dish pelletizer with a diameter of 0.6 m, set at an angle of 45 ° to the surface of the horizon and rotating at a frequency of 12 rpm. Iron ore concentrate is pelletized (Fe oetu 62.8830.

For research, the charge is moistened to 10.5%; embryos with a grain size of 1-2 mm are obtained, which then (with a load of 1.5 kg) are doused for the standard pellets of a fraction of 5-15 mm by feeding the wet charge to the working surface of the pelletizer at an angle (similar to a known method), after which pelletization and processing of lumped materials with compressed air in a rotary pelletizer is carried out. The experiments were carried out according to the known technology and the proposed.

The proposed method is carried out as follows. In the center of the plate, parallel to the bottom surface of the plate, at a distance of 15 mm from its plane, a nozzle for compressed air is installed, through which the stream is fed in cross current to cohesive materials. Compressed air with a pressure of 0.8 MPa is taken from a mobile compres-. weed installation type 0-22 with a capacity of 15 m3 / h.

In the experiments, the effect of the compressed air supply mode (direct flow, countercurrent, cross current), the effect of compressed air consumption and the initial moisture content of the charge (the magnitude

oo

NJ

on prichnost

data is presented in

Table 1

Continued table. 2

table 2

five

0

five

0

five

0

45

As can be seen from the table. 1 data, the greatest increase in the strength of the pellets is achieved under the most optimal condition for supplying compressed air to cohesive materials in the cross-current mode. It allows you to increase the strength of the pellets by 5-7%.

With additional dovlazhnenii in the amount of 0.1-0.25% for every 100 m3 / h-t of compressed air (experiments 2-k, 7-9, 12th, 17-19,) an increase in the strength of pellets by 2.0 -5.9% due to the increased plasticity of the overwetted pellets and an increase in their density and shrinkage during the treatment with compressed air.

Thus, the proposed method allows to increase the strength of the pellets by 13.3-26.9% compared with the known.

Claims (1)

1. A method of producing iron ore pellets, which includes feeding a wet mixture to a pelletizer, pelletizing with wetting, characterized in that, in order to increase the strength of the pellets, the processing of lumpy materials is carried out with a stream of compressed air supplied in a cross-current to the materials.