SU787389A1 - Method of producing cement clinker - Google Patents

Description

(54) METHOD FOR GETTING A CEMENT CLINKER

I

The invention relates to cement production, in particular to the technology of clinker production in kilns equipped with multi-stage baked heat exchangers.

A known method for producing cement clinker in dry kiln furnaces includes, in each case, direct heating of the carbonate and glacial components of the raw mix up to 750-850 ° C in a baking heat mixture and then baked in a rotary kiln (1.

The disadvantages of this method are difficulty, which is caused by the need for separate heat treatment of the components of the raw mix, as well as high heat consumption for clinker burning and low clinker activity, due to the uneven displacement of the pretreated components of the mixture and, consequently, with decreasing reactivity of this mixture. mixture during its sintering in clinker.

The closest technical solution to the invention is a method for producing cement; Klitherser Nogo by the dry method, including sequential heating of the raw mix to 7 50-850 ° C in a multistage fired heat exchanger and its subsequent calcination in a rotary kiln 2.

The disadvantages of the method are high heat consumption for clinker burning, low furnace productivity and low clinker activity, which are due to the fact that the inner surface of the hot steps of the baked heat exchanger, as well as the material being processed

10 of the gases coming from the rotary kiln, alkaline compounds precipitate, resulting in aggregation of the material at .750–850 ° C and a decrease in the intensity of the decarbonization process, as well as an increase in the aero dynamic resistance of the baking system due to formation of weldings in it.

The purpose of the invention is C1 "heat consumption for firing, higher furnace productivity and clinker activity.

20

This is achieved by the fact that in the method of producing cement clinker using the dry method, which includes the sequential heating of the raw mix to 750-850 ° C in a multi-stage baking heat mixer and its subsequent roasting in a rotary kiln, 5-20% of the material heated to 200-400 ° C is taken from the appropriate heat exchanger stage and introduced into the gas stream coming from the rotary kiln into the first stage of the baked heat exchanger. The method is carried out as follows. Cement raw mix. the feeder goes to heat treatment in a multistage baked heat exchanger. When the mixture reaches 200-400 ° C, 5-20% of the processed material is discharged from the corresponding stage and, later, subsequent stages are introduced into the gas flow through the chute, flowing from the rotary kiln into the stove heat exchanger. This part of the material is heated and carried out by the gas stream into the second stage of the heat exchanger, where it is mixed with the rest of the material that has passed through all the steps of the furnace heat exchanger and enters the rotary kiln. When processing a powdered raw material mixture in a baking heat exchanger, its dispersity changes as the temperature rises to 750-850 ° C. At 200-400 ° C, a dispersion of the mixture is observed, due to the evaporation of water and the degradation of glycete minerals. In terms of further increase in the temperature of the mixture, aggregation is observed, which is caused by the interaction of carbonate component particles coated with amorphous calcium oxide, as well as the adhesive power of alkaline compounds condensed on the surface of these particles. This is a phenomenon. aggregation of the particles of the raw mix leads to a decrease in the intensity of the decarbonization process in the baking system and the sintering process due to a decrease in the dispersion of the mixture, as well as to a decrease in clinker activity and, consequently, to an increase in heat consumption for calcination. In addition, aggregation of the raw material particles leads to their deposition on the inner surface of the cyclones and ducts of the heat exchanger, their smearing, the formation of wallings and welds, the elimination of which requires stopping the furnace and cleaning the gas path, which ultimately results in a decrease in the furnace's hourly average performance. When a part of a highly dispersed material heated to 200-400 ° C is introduced into the gas flow from the rotary kiln to the baking heat exchanger in the hot stage of the heat exchanger, the dispersion of the mixture increases in comparison with the known method. This leads to more uniform precipitation. alkali1P.1X connections to the material to be treated and to REDUCE the possibility of smearing the flues and cyclones of the baking system. An increase in the dispersion also leads to an increase in the intensity of the decarbonization and sintering processes, i.e., an increase in the productivity of furnace 9.4, a decrease in heat consumption for clinker burning and an increase in clinker activity. The table presents the comparative figures of the known and proposed methods tested on a 4x60 m furnace with a four-stage cyclone heat exchanger. The content of fractions of more than 80 microns in the original raw mix,% 1717 in the mixture at the exit from the fourth stage (200 ° C),% 1212 in the mixture at the exit from the third stage (400 ° C),% 1414 in the mixture at the exit from the second stage ( 600 ° C),% 1818 in the mixture at the outlet of the first stage (800 ° C),% 2820 heat of decarbonization of the raw mix at the inlet to the kiln,% 1518 heat for clinker burning, kcal / kg830800 Average hourly productivity of the furnace, t / h3435 Activity clinker, kg / cm 400 450 Time factor for calendar use 0.86 0.92 Economic effect from the introduction of the proposed invention for one cent elementwise plant capacity of 1200 tons clinker is greater than 1 million rubles.; in year. A method of producing cement clinker using a dry method, including sequential heating of the mixture to 750-850 ° C in a multistage baking heat exchanger and its subsequent calcination in a rotary kiln, which is characterized by the fact that in order to reduce the consumption of tegote roasting, increasing furnace productivity and clinker activity, 5–20% of the material heated to 200–400 ° C, take about 10–70% of the irvnoH. chg material.

5787389 6

meinik and introduced into the gas stream, enter-1. USSR author's certificate N 359490,

from the rotating pet to the first step. F 27 B 7/34, 1972.

baking heat exchanger. Banit FG, et al. Mechanical equipmentSources of information, cement cement concepts. M., Mechanical Engineering,

taken into account in the examination. 1965, p. 173-194.

Claims (1)

Claim A method of obtaining a cement clinker by the dry method, which includes sequential heating of the raw material mixture to 750-850 ° C in a multi-stage baking heat exchanger and its subsequent firing in a rotary kiln, characterized in that, in order to reduce heat consumption for firing, increase the productivity of the furnace and of clinker activity, 5-20% of the material heated to 200-400 ° C is taken from the corresponding hot gas / psch '• epps'G'Z main cup and introduced into the gas stream coming from the rotary kiln to the first stage of the baking heat exchanger.