SU1103799A3 - Method for controlling blast furnace smelting - Google Patents

Abstract

1. METHOD FOR MANAGING DOMATIC MELTING, which includes the reduction of iron ore materials, the production of pig iron with up to 2% silicon, blowing through heated tuyeres to 1500-2800 ° C reducing gases containing up to 50% by volume of nitrogen and not more than 6.9% amounts of CO + H2O, the rest of CO + H, when coke consumption is charged through the throat, is within 50–350 kg / t of pig iron, characterized in that, in order to reduce the energy costs of producing iron by adjusting the coke consumption. the temperature of the pig iron and / or the silicon content in it, simultaneously change the temperature and composition of the blown hot reducing gases, and to increase, the coke consumption increases, and to decrease the temperature and the content of COj and / or and / or nitrogen, to increase the temperature pig iron and / or Si content increases the temperature and reduces the content of COj and / or HjO, and to decrease it decreases the temperature and increases the content of COj and / or, to increase productivity. reduce the content of CO and / or and / or nitrogen and increase the temperature, and to reduce it increase the content of CO and / or and / or nitrogen and reduce the temperature; to increase the temperature of the flue gas, they decrease the temperature and increase the content of CO and / or NO, and / or nitrogen, and to decrease it increase the temperature and decrease the content of CO and / or H, O, and / or nitrogen. 2. A method according to claim 1, characterized in that hot air or air enriched with oxygen is blown into the blast furnace through at least one of the tuyeres not used for supplying reducing gases.

Description

The invention relates to ferrous metallurgy, in particular to the blast furnace production of iron using hot reducing gases. There is a known method for controlling blast-furnace smelting with injection of hot reducing gases produced outside the blast furnace at the level of main blast tuyeres together with blowing or oxygen. reducing coke consumption and increasing productivity 11. However, the implementation of this process does not use all the advantages of the process, in which hot reducing gases completely replace the functions of coke as a source of the body and reducing gases, leaving behind only the role of the nozzle necessary for the drainage of liquid smelting products during counterflow gases t The closest to the technical essence of the invention is a method for controlling blast-furnace smelting, including the reduction of iron ore materials by blowing through heated tuyeres from 1500 to 1800 ° C with reducing gases, containing up to 50 vol. nitrogen and not more than 6.9% of the amount of the rest is CO + H, with the consumption of coke loaded through the furnace top in the range of 50-3SO kg / t of pig iron 2. However, the implementation of the method does not regulate one or several parameters of the blast furnace, which does not allow to obtain the maximum reduction in energy costs for the production of pig iron, but the commonly used control methods only have an effect after a few hours. The purpose of the invention is to reduce the energy costs of producing pig iron by adjusting the coke consumption of the iron temperature and / or silicon content therein. This goal is achieved in that according to the method of controlling blast furnace smelting, including the reduction of iron ore materials, the production of pig iron with a silicon content of up to 2%. blowing through tuyeres of reducing gases containing up to 50 vol% azo, heated to 1500–2800 ° C. and no more than 6.9% of the amount, the rest is CO + N.O., when the coke consumption is charged through the throat, in the range of 50-350 kg / t of pig iron, the temperature and the composition of the blown hot reducing gases are simultaneously changed / and to increase the flow rate coke is increased, and to lower the temperature, the content of COj and / or HjO and / or nitrogen is reduced, to increase the temperature of the iron and / or Si content, the temperature is increased and the content of CO and / or HjO is reduced, and to decrease, the temperature is reduced and the CO content is increased / or to increase the productivity of the mind Reduce the CO2 and / or, and / or nitrogen content and increase the temperature, and to decrease it increase the CO and / or and / or nitrogen content and decrease the temperature, decrease the temperature and increase the CO and / or HjO content to increase the temperature of the flue gas. / or nitrogen, and to decrease it, increase the temperature and decrease the CO content and / or, and / or nitrogen. Hot air or air enriched with oxygen is blown into the blast furnace through at least one of the tuyeres that are not used to supply the reducing gas. When implementing the invention, a high-speed change in temperature and reducing ability of the injected gas is carried out, allowing in the first phase to fix the necessary coke consumption to ensure drainage of liquid smelting products, and then quickly adjust the composition and temperature of the pig iron, production rate and temperature of ejection gases. The composition and temperature of the reducing gases is controlled outside the blast furnace in the reactor by setting the desired ratios between the fuel and the oxidizing gas entering the reactor, and the temperature using the heat supply to the reactor, for example, changing the flow of electricity to the reactor to heat the reducing gases supplied to bake. The ability to introduce oxidizing gas into the furnace is provided when the coke nozzle in the furnace is to be renewed and when the drainage capacity is lost. Examples of a specific implementation of the method are given in Tables 1-5, obtained on an experimental blast furnace and illustrating the advantages of the proposed method.

The results of the comparison of the known method of conventional coke smelting and the proposed

Table

Regulation of coke consumption by changing the temperature and composition of the top gas

Indicators

amount, (,),% (Nj + Ar),% amount, temperature, ° C flow rate, kg / t Si content,% temperature, s

temperature, ° С

table 2

Adjustable

Base period period

3.4 42.2 1900 2020

105 0.78 1435

124

Regulation of the gas content in the iron and its temperature

Table 3

Regulation with blown heated reduction

If, for some reason, it is necessary to implement a process with a higher coke consumption than with a process with blowing hot reducing gases without loading coke through the throat (for example, to exchange the coke nozzle in a furnace), this is achieved by using simultaneous. Mention of superheated blown-ups Table 5

of gases

new gases through a certain amount of tuyeres, and through the remaining tuyeres - the flow of hot air.

The implementation of the proposed method 25 allows operatively regulating the most important parameters of the blast furnace smelting in a wide range, significantly reducing the energy costs for the production of pig iron.

Claims (2)

1. METHOD FOR MANAGING A DOMAIN Smelting, including the recovery of iron ore materials, production of cast iron with a silicon content of up to 2%, blowing through lances of reducing gases heated to 1500-2800 ° С, containing up to 50 vol.% Nitrogen and not more than 6.9% of the total СО ₂ + Н ₂ 0, the rest С0 + Н ₂ , at a consumption of coke loaded through the top, within 50 350 kg / t of cast iron, characterized in that, in order to reduce energy costs for producing cast iron by controlling the consumption of coke, temperature pig iron and / or its silicon content, simultaneously change the pace the temperature and composition of the injected hot reducing gases, moreover, to increase, the coke consumption is increased, and to reduce the temperature and the content of СО ₂ and / or Н _g О and / or nitrogen are reduced, to increase the temperature of cast iron and / or the Si content, the temperature is increased and reduce the content of CO _? and / or H ₂ O, and to reduce - reduce the temperature and increase the content of CO _? and / or H ₂ O, to increase productivity, reduce the content of содержаниеCO ₂ and / or H ₂ O and / or nitrogen and increase the temperature, and to reduce it, increase the content of CO ₂ and / or H ₂ O, and / or nitrogen and reduce temperature; to increase the temperature of blast furnace gas, reduce the temperature and increase the content of CO ₂ and / or H ₂ O and / or nitrogen, and to reduce it, increase the temperature and decrease the content of CO ₂ and / or H ₂ O and / or nitrogen. 2. The method according to claim 1, characterized in that hot air or oxygen enriched air is blown into the blast furnace through at least one of the tuyeres not used for supplying reducing gases. THX Noaaa Oh with m f