SU956589A1 - Process for producing manganese ferroalloys - Google Patents

Description

one

This invention relates to the metallurgy of ferrous alloys, in particular manganese ferroalloys.

Methods for the production of ferroalloys are known, which provide for the supply of carbonaceous reductant 1 to the production of manganese ferroalloys in the production of manganese ferroalloys.

Moreover, to increase the completeness and rate of reduction reactions, idi) in the kinematic mode, it is necessary to have a small fraction of the reducing agent in the process, since the rate of the reactions depends on the contact surface between the reducing agent and the oxide melt. However, the supply to the initial mixture of the fine fraction impairs the gas permeability of the top furnace, which entails various technological preparations, the most significant of which are sintering and freezing of the mixture. As a result, its uniform descent is disturbed, and especially during melt outflows from the furnace, leads to the furnace top collapses. Hitting the high temperature zone during the landslides, the wet ore part causes slag emissions from the furnace, and also leads to an increase in the hydrogen content in the exhaust gases, which is unacceptable due to the increase in their explosive hazard.

The closest in technical essence and the achieved result to the proposed method is the production of manganese ferroalloys, in which it is proposed to supply the reducing agent in the form of briquettes 2.

ten

However, these strong briquettes retain their mechanical properties in a furnace. Their use does not allow to have a carbonaceous reducing agent of the small 15 fraction in the reaction zone, which significantly reduces the intensity of the process.

The purpose of the invention is to intensify the process of smelting manganese ferroalloys.

The goal is achieved by the

20 electric smelting of a mixture containing manganese concentrate, flux, steel shavings, carbonaceous reducing agent, 10-60% of the total amount of reducing agent is introduced into the 39 kiln furnace in the form of briquettes scattered at a temperature of 1100-1200 ° C. The proposed method allows without degrading the gas permeability of the top, to have a small fraction of the reducing agent in the reaction zone. The limits of the scattering temperature of briquettes are the temperatures of the onset of reduction reactions and, therefore, the appearance of fines of carbonaceous reducing agent promotion zone. The amount of pre-briquette should be in the range of 10 to 60% of the total amount of reducing agent. If its amount is less than 10%, then this does not allow any noticeable increase in the efficiency of the process. And a 60% increase in results in an uneven distribution of the reducing agent throughout the entire batch volume and, as a result, also leads to a decrease in efficiency. In addition to influencing the chemistry of the process, the fines of the carbonaceous reductant in the reaction zone also affect the electrical mode, increasing the resistance of the furnace, thereby allowing the smelting at a higher voltage. And, as practice shows, when operating at higher stresses, it becomes possible to increase the power of the melting units by increasing the cos utilization of electrical energy, i.e. by reducing its losses. Coke breeze, which is not capable of sintering, remains loose in the entire temperature range that occurs in an electric ferroalloy furnace at the height of manganese alloys; therefore, it cannot be used in the charge for their smelting, because it reduces the gas content of the cauldron and causes process frustrations. However, various binder having the most different thermal resistance can be used for its pelletizing. Among the most common are sulphide-alcohol bard, whose strongest properties are lost when heated to 400-500 ° C, resins, bitumens and pitches (thermal strength up to 700-800 ° C) and finally liquid glass, which at 11001200 ° C is converted to sodium silicate, which also does not have stinging properties. Since there is no noticeable chemical interaction between the carbon structure of coke and sodium silicate during this telemetry, the coke breeze briquette prepared on this binder is dispersed at the indicated temperature into powder of initial size, which is established experimentally when these briquettes are heated at a rate of 10 deg / min , under pressure of 0.2 kgf / cm, simulating the conditions of a low-shaft electric furnace. Experimental smelting of carbon FeMn in a three-electrode semi-industrial furnace with a capacity of 1600 kVA was carried out with the replacement of 50% of coke in the charge briquetted with coke breeze. In the smelting process, a standard FeMn is obtained. The results of smelting on experimental and ordinary charge are given in the table. As follows from the above data, the method of smelting manganese ferroalloys with the use of dissolving briquettes from fine carbon reducing agent contributes to an increase in the extraction of manganese and a decrease in the specific consumption of charge materials. The economic effect due to a decrease in the cost of the alloy is 1.5 p per 1 ton of ferromanganese.

22922289

652652

484459

-24

7575

75,7.75,8

74 77.3

74 76.7

75 75.9

76 75.9

5956589.6

Claims (2)

The invention claims, l of its total amount, is introduced into the furnace. Method for the production of manganese ferro-1100-1200 ° C. alloys, including electric smelting charge. Sources of information, containing manganese concentrate, flux, 5prints in the examination steel shavings, carbon sriketiro-1. Mizin V. G., Serov G. V. Carbonaceous Reducing agent for ferro-slurry. M., Meshch, and with the fact that, with the aim of intensiveness; Tallurgizdat, 1976, p. 38 process of smelting manganese ferro 2. For Japan Japan number 27325, cl. 10} 121, alloys, 10-60% carbon recover- to 1973. briquettes growing at a temperature