SU1433994A1 - Method of nodulizing ores and concentrates - Google Patents

Abstract

The invention relates to non-ferrous and ferrous metallurgy and can be used in the preparation of raw materials for blast smelting. The purpose of the invention is to increase the productivity of the sintering process. The invention is carried out as follows. Before sintering, the mixture is metered, mixed, moistened, pelletized, and sent to sintering. The fuel used is coke breeze with a particle size of 3 mm. Sintering is carried out in an agglochase with a sintering area of 0.05 m at a height of 500 mm under air pressure, which is fed under the hood of the agglochate in a pulsating mode at a pulsation frequency of 10-600 units / min and amplitude constituting 10-75% of the mean pressure above the bed. 1 tab. (L

Description

four

00 00

with

with

4ib

The invention relates to metallurgy and can be used in the preparation of raw materials for blast furnace smelting. The purpose of the invention is to increase the production and water content of the sintering process.

The invention is carried out as follows.

Before sintering, the agglomerate is metered, mixed, moistened, thoroughly pelletized, and sintered under pressure. As fuel, coke breeze with a particle size of 0–3 mm is used, whose sieve composition corresponds to that typical for ag-J5 lofabrik. Compressed air under the agglobe cap is fed through the piping system in an amount necessary to obtain a given pressure above the charge layer.

The pulsating mode of supplying compressed air under the hood is organized by reciprocating rotation of the damper with a frequency of 10-600 units / min with an amplitude of 75-10% of .25 The average pressure above the bed.

The proposed limits of pulsations and amplitudes are chosen from considerations of the most efficient combustion of the fuel component of the charge under pressure. As the frequency of oscillations increases from 10–500 units / min with a decrease in the amplitude of the pulsation from 75 to 10% of the average pressure above the bed, the burning rate of the fuel increases by more than 25%.

Violation of optimal conditions, i.e. specified frequency limits and pulsation amplitude, leads to disruption or a sharp deterioration of the process, fuel burning (observed when choosing the mode, pressure pulsations with a frequency of less than 10 units / min and amplitude of more than 75% of the average pressure above the bed. When choosing a frequency greater than j 600 units / min with an amplitude of less than 10% of the average pressure, the process is practically the same as usual sintering under pressure.

Under optimal conditions of change

50

pulsation frequencies and amplitudes are created favorable conditions in the layer, allowing to organize the mode of pulsating filtration of gases in the layer, allowing to destroy the shell consisting of combustion products 5 to increase the diffusion rate of oxygen to the reaction surface of the fuel, thus increasing its burning rate.

j

0

five

The proposed method is implemented by adjusting the pulsation of the compressed air through the reciprocating rotation of the valve located on the path of air supply to the duct above the layer.

Example. The sintering is carried out in an agglobal sintering area of 0.05 m with a height of 500 mm. The mixture consists of ore and concentrate at a ratio of 1: 4 - 60%, 13% limestone, 5% fuel, the amount of return is 4% relative to the weight of the charge, the moisture content of the charge is 8%. During the sintering process, the sintering time and the quality of the agglospace are determined.

A pulsating supply of compressed air is carried out by a reciprocating rotation of the damper installed on the path of air supply to the layer. The initial air pressure above the layer is 0.5 atm. Conduct a series of experiments with appropriate pulsation limits. To compare the results, sintering is also carried out by a known method.

The main indicators of sintering are given in the table.

It follows from the above data that the proposed method of sintering ores and concentrates is characterized by higher rates of sintering process as compared to the α prototype.

When the pressure pulsation conditions are observed above the sinter charge layer with a pulsation frequency of 10-600 units / min and an amplitude of 75-10% of the total pressure above the layer, the vertical sintering rate increases by increasing the diffusion rate of oxygen to the reaction surface of the fuel.

Claims (1)

Invention Formula The method of agglomeration of ores and concentrates, including dosing, mixing, moistening, pelletizing of the charge and its subsequent sintering under air pressure, characterized in that, in order to improve the performance of the sintering process, air is fed into the layer periodically with a pulsation frequency of 10-600 units. (MtiH) with an amplitude of 10-75% of the average pressure above the bed during the entire sintering time.