CS243518B1 - Cement clinker production equipment - Google Patents

Abstract

The purpose of the device according to the invention is, less fuel or combustible waste it is incinerated or gasified with a podstoichiometric amount of air and the resulting combustible the semi-gas is only burned after addition additional - secondary combustion air directly at the place of heat demand. This is achieved by the device for the production of cement clinker consisting of from a dispersion preheater, rotary furnace, the calcining channel of the gas directly connected to a dispersion preheater, mutually connected to the production line by it is provided with a gasifier (1) for gasification less valuable fuels, while the / 3 / of the combustible gas from the generator (1) into the channel (6) of the gases leading from the rotary furnace / 5 / into a dispersion preheater (4).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for the production of cement clinker employing a separate calcination technology in which the thermal content of low-value fuels is used for the calcination process.

Devices are known in which low-value fuel or combustible waste with a high ash content is combusted directly in the clinker production process. However, the ash formed, which comes into contact with the cementitious raw material only in the firing process, is not perfectly mixed with the limestone and other constituents present and tends to be separated from the processed material so that it is not homogeneously distributed in the raw material. inhomogeneous with an impact on quality.

Known solutions to this problem therefore consist in the use of a noble fuel for the sintering and decarbonisation reactions, a part of which is replaced by a combustible combustible material that satisfies neither the calorific value nor the ash content and therefore cannot be used directly in the process and is therefore a separate combustion plant outside the zone or zones where endothermic reactions take place and the heat is transferred to the heat demand point by the hot combustion gases.

However, most of the heat in the other combustion apparatus is released in the process of flawless combustion of low-grade fuel with sufficient excess air, which provides enough oxygen to burn the noble fuel needed to obtain sufficient temperature in the sintering zone of the rotary kiln.

However, the temperature of the flue gases and hot gases exiting from this afterburner has a maximum value of 900 ° C due to the non-exceedance of the softening and melting point temperatures of the ash (see British Patent No. 1,561,966).

However, the greatest proportion of heat is released in this way, not immediately at the place of heat demand, but in said afterburner, whereby the efficiency of utilization of both low-value and waste fuels is greatly reduced.

These drawbacks are overcome by a cement clinker plant consisting of a dispersion preheater, a rotary kiln, a calcination channel of gases directly connected to the dispersion preheater, interconnected to a production line according to the invention, which is based on a generator for gasification of low-grade fuels. wherein the combustible gas conduit from the generator is connected to a gas passage leading from the rotary kiln to the dispersion preheater.

The main advantage of the device according to the invention is that the low-value fuel or combustible waste is combusted or gasified with a substoichiometric amount of air and the combustible half-gas produced is combusted only after the addition of an additional secondary combustion air directly at the heat demand point.

The drawing schematically shows a device according to the invention in a front view.

The attached figure represents a part of a device for producing cement clinker, consisting of a rotary kiln 4 and a dispersed preheater 6 of the feedstock being interconnected by means of a gas channel 6, this arrangement, known from U.S. Pat. No. 214650 is furthermore provided with a fuel generator 2 with a fuel inlet 2 and a gas conduit 6 which opens into the lower part of the gas passage 6 from the rotary kiln 6 to the dispersion preheater 4.

In the generator 1, a low-value fuel is converted into a combustible gas which is introduced via a gas line 3 into the lower part of the gas passage 6, in which the hot gases from the rotary kiln 6 flow upwardly carrying the pre-heated feedstock in the so-called circulation circuit between the rotary and a dispersion preheater 6, wherein the combustible gas from the generator 6 after being combined with the free oxygen contained in the hot gases from the rotary kiln 6 is combusted and the heat released is used to calculate the entrained feedstock.

The raw material with a higher degree of calloinisation is then fed into a rotary kiln for further processing, whereby an increased degree of calcination has the effect of achieving a higher specific kiln line performance.

This arrangement is particularly important for the refurbishment of existing furnace lines, where only a small increase in output is required without major reconstruction and investment costs, that is to say, when there is an effort to utilize potential performance reserves of the existing furnace line. The increase in performance in these cases is in the range of about 20-30%.

Claims (1)

SUBJECT OF THE INVENTION Apparatus for the production of cement clinker consisting of a dispersion preheater, a rotary kiln, a calcination channel of gases directly connected to the dispersion preheater interconnected to a production line, characterized in that it is equipped with a generator (1) for gasification of low-value fuels of the generator (1) is connected to a gas passage (6) leading from a rotary kiln (5) to a dispersion preheater (4).