SU1490101A1 - Method of cement clinker - Google Patents

Abstract

The invention relates to the building materials industry, primarily to the production of cement clinker. The aim of the invention is to increase productivity by intensifying the firing process. The mixture of the clay component is heat treated with a carbonate part in cyclone heat exchangers and a part of the carbonate component in another system of cyclone heat exchangers and in a fuel injection thermal reactor, the components are mixed and fired in a rotary kiln 35-80% with stabilization of its combustion at 3000-8000 ° C with the subsequent addition of ash to the carbonate component. 1 tab., 1 Il.

Description

The invention relates to the industry of building materials, mainly to the production of cement clinker.

The purpose of the invention is to increase productivity by intensifying the firing process.

The drawing shows the implementation of the method.

The scheme contains left 1 and right 2 heat exchangers, a thermal reactor 3 with an expanding cyclone device 4 and furnaces 5 in which heating devices 6 and a fuel input device 7, a device 8 for mixing all raw materials, a rotary kiln 9 and a refrigerator are located. ten.

The method is carried out as follows.

A part of the prepared steam mixture, including a clay component with a carbonate part and with added additives, is fed into the heat exchanger system 2, the remaining carbonate component is fed into the heat exchanger system 1. In the heat exchanger system 2, the raw material is heated by exhaust gases from the rotary kiln 9, and heat exchangers 1, the heating of the raw materials is carried out with waste gases of the thermal reactor 3. For combustion, thermal fuel 3 is fed with solid fuel or industrial waste with high ash content for 40-60% of ETS obsche4 ;:

with

amount of fuel needed to produce clinker. The fuel introduced through the device 7 undergoes ignition and combustion stabilization by means of a heating device 6, which provides a temperature in the fuel inlet zone of 3000-6000 K in the combustion chamber 5. A plasma generator (plasma torch) can be used as a heating device. In the reactor 3, the raw material is subjected to intense heat treatment in a suspended state, then separated from the gas stream in the cyclone expansion device 4 and fed after mixing with the clay component in the device 8 into the rotary kiln 9. After sintering, the clinker is cooled in the refrigerator 10. In the furnace reactor there is a natural change in the xy-1 composition of the carbonate component due to the addition of a solid fuel floor in a finely dispersed state, due to the thermal shock that the solid undergoes Pliva at 3000- 6000 K. The amount of ash, introduced with the solid fuel ash with 55- 70%, is 10-60% of the quantity necessary to obtain a clinker clay additives.

The table shows the comparative results of firing on the proposed and known methods. The performance of the firing method according to a known method at a relatively low ash content of the fuel (about 23.) is taken as 100% (example 1). With an increase in the ash content of the fuel to ()% calcination is impossible,. Stabilization and steady burning of this PM. PIBL is not ensured (Example 2).

Elimination of the stabilization of combustion of fuel at a temperature of 3000-6000 K will significantly increase the burning rate} g of fuel at ash content up to 70%. The decrease in temperature in the input area of 3000 K does not provide stabilization of combustion even at ash content of fuel 23% (Example 9), Increasing the temperature of stabilization of fuel combustion in the 6000 K reduces both the operating efficiency of the heating device and the efficiency of heating the fuel due to the deterioration of the thermophysical properties of the gas at this temperature.

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Stabilizing the combustion of solid fuels makes it possible to raise the temperature in the reactor, the degree of decarbonization in this case increases by 5-10% compared with the known. The growth of furnace productivity does not exceed 5% in this case (example 3). This is due to the fact that the amount of ash with the ash content of the fuel up to 35% is small and amounts to less than 5% of the amount of clay additive required for clinker production and there is no significant intensification of the clinker formation. When the ash content of the fuel exceeds 35%, the amount of ash as a clay additive reaches 10% and the furnace productivity increases by JO-15% (Example 4.5). Further, with an increase in the ash content of the fuel, the amount of fine ash in the clinker increases, the intensity of the clinker formation in the furnace also increases, however, the decarbonization rate in the reactor decreases and the furnace productivity first increases with the ash content of fuel 50-60% to 120-125% and then decreases 105-110% with ash content of fuel 70% (example 6-7). A further increase in the ash content of the fuel leads to a rapid decrease in the temperature in the reactor and a decrease in the degree of decarbonization, and hence to a decrease in the productivity of the furnace to almost zero due to the release of defective products (Example 8).

Thus, the use of high-ash fuel and the stabilization of its combustion at 3000-6000 K and the addition of ash to the carbonate component of clinker significantly increase the intensity of the burning process. Oven productivity growth due to this will be 5-25%,

The use of the proposed method for obtaining Portland cement clinker allows, in comparison with known methods, to significantly expand the fuel base of cement industry due to the highly efficient use of fuels with high ash content.

Due to the addition of fine ash to the carbonate component in the thermal reactor, the stability of the resulting cement clinker is ensured, since the ash content in the pulverizer is small and relatively constant. This cannot be achieved by introducing high-grade fuel directly into the rotary kiln, when the ash additive may be different along the kiln length, which causes changes in the chemical composition of the clinker.

Claims (1)

The use of the proposed method is especially effective in areas of Central and Eastern Kazakhstan, Western Siberia and Krasnoyarsk Krai, where the cost of 1 ton of equivalent fuel for solid fuel is 1.5–5 times lower than for fuel oil and natural gas. Invention Formula Method for the production of cement clinker by heat treatment mixture of clay component with carbonate part in cyclone heat exchangers and part of carbonate component in another system of cyclone heat exchangers and in a thermal reactor with the introduction of fuel, subsequent mixing of components and burning in a rotary kiln, characterized in that, in order to increase productivity due to process intensification roasting, during heat treatment of the carbonate component, fuel is introduced into the thermal reactor with an ash content of 35-60% with stabilization of its combustion at 3000-6000 s followed by ash addition to the carbonate component. The technological parameters of the proposed method of firing Carbonate component Gift air, JotinuBo 40-60% Clay component f partly foHamHoto