SU436089A1 - METHOD OF OBTAINING METALLIZED CONCENTRATES FROM BOROZHELEZNYAKOV OLOLITOVSKIY ORE - Google Patents

Description

one

This invention relates to the preparation of a charge for blast furnace smelting.

A known method of producing reduced metallized raw materials from iron-rich oolitic oolitic ores with a high content of silica, alumina and phosphorus, including the mixing of materials, their heating, reduction and grinding.

The recovery process is carried out with solid fuel at 1250-1350 ° C.

The disadvantages of this method are the low specific productivity of the furnaces, the difficulty of maintaining the process conditions due to the formation of inclusions, the possibility of the transfer (up to 85%) of phosphorus into the product.

In order to reduce the phosphorus content in the metallized concentrate and to obtain a silicon module in it not lower than 1.3-1.6 in the proposed method, a mixture of ore with a solid reduction in the ratio of 1: (0.5-1) is heated for 1-1.5 hour to 950 ° C, followed by exposure of the material for 2.5-3 hours at 950-1000 ° C.

By the proposed method, it is possible to obtain a metallized concentrate with an iron content of up to% s. by a simultaneous decrease in the content of harmful phosphorus and

/ StO,

alumina, silicon module

on I A1,0z /

the level of 1.3-1.6.

In the crystal lattice of oximagnetites formed during reduction at 950 ° C, a certain part of trivalent iron is replaced by aluminum, resulting in a hercinite solid solution. In the process of recovery when

950-1000 ° C. The solid solution decomposes with the release of metallic iron and the iron-poor oxide phase of Hercinite. During the subsequent formation of iron silicates, the main part of phosphorus is concentrated in

they, and with further grinding and magnetic separation of the product, hercynite, iron silicates and the phosphorus concentrated in them go to waste.

Relatively high iron recovery and

removal of phosphorus and alumina in the metal concentrate is achieved at a reduction temperature of 950-1000 ° C and a reduction time of 2.5-3 hours, causing the formation and coarsening of the metal phase and the complete formation of the slag-forming material.

As the temperature decreases (; 950 ° C), the quality of the concentrate drops sharply and the content of harmful impurities increases. As the temperature rises above 1000 ° C, the amount of iron silicates significantly increases, which reduces iron recovery in the "concentrate". The method involves the process of reducing the iron ore material in any of the known calcining units. The proposed method was tested on an integrated laboratory rotary kiln. From Lysako-scoop concentrate containing,%: Iron 49.5 Silica 8.6 Alumina5.1 Phosphorus 0.78 Hydrate Moisture 14 a concentrate was obtained containing,%: Iron Phosphorus Silica3-4 Alumina 1.5-3. The subject of the invention is a method for producing metallized concentrates from red-iron ore to oolitic ores with high content of silica neem, alumina and phosphorus, including mixing materials, heating them, heating and grinding, characterized in that in order to reduce the phosphorus content and to obtain a silicon module e "similar to 1.3, a mixture of ore with a solid reducing agent in a weight ratio equal to 1: (0.5-1), is heated for 1-1.5 hours to 950 ° C, followed by holding the material for 2.5- 3 hours 1pri 950-.1000 ° С.