JPS5935851B2 - Dry cement manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a tubular rotary furnace, a preheating device with a cyclone, and a method for manufacturing a rotary furnace arranged in the path of the material between the last cyclone and the penultimate cyclone of the preheating device and the furnace. and a combustion chamber into which a portion of the fuel required for the production of dry cement is injected.

In known installations of this type, the entire flow of smoke from the furnace and combustion chamber passes through the preheating device, so that at the outlet of the preheating device a considerable amount of the smoke is treated at a relatively low temperature, and therefore the heat content of the smoke There is little profit to be made even if the amount is recovered.

The preheating equipment is divided into two groups of cyclones, one group of cyclones is used to pass smoke from the furnace to heat a portion of the raw material, and the other group of cyclones is used to pass the smoke from the furnace to heat a portion of the raw material. Pass the smoke from the combustion chamber to heat the rest of the processed material.

This solution is not superior to conventional solutions in terms of smoke heat recovery.

The purpose of the invention is to improve the recovery of heat by increasing the temperature of one part of the smoke and using up the remaining part of the smoke more completely in a way that does not significantly increase the consumption rate of the equipment. be.

Similarly, the invention allows for a modest increase in the production rate of existing conventional equipment that does not include a combustion chamber, without significantly increasing the consumption rate of the equipment.

The installation that is the object of the invention comprises at least one auxiliary cyclone arranged in the path of the material between the penultimate cyclone of the preheating device and the combustion chamber and heated by at least a part of the smoke from the furnace. The preheating device receives the entire smoke from the combustion chamber and possibly the remainder of the smoke from the furnace.

Instead of a single auxiliary cyclone, it is also possible to use a group of cyclones arranged in series in the path of the material so that the smoke from the furnace passes in succession and provides countercurrent heat exchange.

In particular, the entire flow of smoke from the furnace can be passed through the auxiliary cyclone or cyclones, while the preheating device receives only the smoke from the combustion chamber.

The smoke from the auxiliary cyclone or cyclones can be used as a heating fluid in the boiler to generate steam.

In this case, excess hot air from the clinker chiller can be mixed with the smoke, allowing a single boiler to recover the heat content of the hot air and smoke.

The smoke likewise serves to reheat the secondary air from the combustion chamber.

In this case the waste heat boiler is heated by air from the cooling device.

In some cases, it is possible to recirculate a portion of the material exiting the last cyclone of the preheater into the combustion chamber to improve burnout.

Other features and advantages of the invention will be explained in detail below with reference to the accompanying drawings, which illustrate two embodiments of the invention.

The equipment shown in FIG. 1 includes a preheating device equipped with four cyclones 1 to 4, a tubular rotary furnace 10, and a clinker cooling device 1.
2.

The cyclone 4 is connected to the phase inspection hood from the furnace 10 via a duct 14, and the four cyclones are connected to the duct 16, 18.
, 20 are connected in series.

The outlet of the cyclone 1 is connected to the suction port of the ventilation device 22.

Furthermore, the equipment of the invention includes a cyclone 24 having an inlet connected via a duct 26 to a phase detection hood from the furnace.

The outlet of the cyclone is connected to the inlet of the heating fluid circuit of the boiler 28.

The material outlet of the cyclone 3 passes through the duct 26 and the material outlet of the cyclone 24 passes through the duct 14.

The burner 30 is mounted in a conventional manner at the end of the furnace adjacent to the cooling system, and the fuel is fed into the combustion chamber 30, which merges with the duct 14.
Similarly, the combustion chamber receives the air necessary for combustion from 34.

The air can be extracted as shown by the dotted line (on the cooling device 12).

The combustion chamber can be constituted by the duct 14 itself, suitably modified to allow injection of fuel and air downstream of the point of introduction of material from the cyclone 24.

Similarly, the chamber can be attached to the duct 14 in such a way that the furnace smoke circulating in the duct 14 and the material introduced into the duct upstream of the chamber pass.

The raw material is introduced from A into the duct 20 and is carried by the gas circulating there to the cyclone 1 where it is separated from the gas stream.

The raw material is then introduced into duct 18 and sent to cyclone 2.

Thus, the raw materials are passed through cyclones 1, 2°3 before being introduced into the furnace.
．． 24, 4 in succession.

The smoke from cyclone 1 can be used to dry the raw material.

The smoke exiting the cyclone 24 is fed to a boiler 28 which utilizes the heat of the smoke to generate steam.

The smoke from the cyclone 24 may be mixed with excess hot air from the cooling system 12 (thus, the amount of heat is transferred to the boiler 28).
It can be collected within

This possibility is illustrated by the dotted line in FIG.

FIG. 2 shows a modified version, in which the separate combustion chamber 40 has only one outlet common to smoke and material, which outlet is connected to pipe 4.
2 is connected to the duct 14.

The material exiting cyclone 24 is introduced into chamber 40 where it is placed in suspension in the air stream entering from 34.

Fuel is injected into the chamber from 32. The smoke produced in chamber 40 by the combustion of fuel and air is fed by pipe 42 to tact 14 where it mixes with smoke from the furnace directed towards cyclone 4.

The smoke carries material out of chamber 40 and into cyclone 4.

The installation shown in Figure 3 differs from that in Figure 2, the main difference being that the total amount of smoke from the furnace is reduced to cyclone 24 and boiler 2.
8, and the cyclone of the preheating device receives only 40 smokes into the combustion chamber.

In this installation, a portion of the material from cyclone 4 was recirculated to the combustion chamber, as shown by the dotted line, to ensure more complete smoldering.

FIG. 4 shows another arrangement according to the invention in which the smoke from the furnace is removed from the combustion chamber 400 before being used in the indirect heat exchanger 54 to reheat the secondary air. It passes through two cyclones 50 and 52.

Cyclones 50, 52 constitute an auxiliary heat exchanger that uses smoke from the furnace to heat the material exiting cyclone 3.

At the exit of the cyclone 52, material is fed into the combustion chamber 40.

In this installation, the hot air from the clinker cooler not used in the furnace can be fed to a boiler where it imparts heat to the vaporizable fluid and then It is recirculated in the cooling system as described in the Japanese Patent Application Publication No.

The installation according to the invention allows the use of conventionally used installations by adding a combustion chamber (or a modified duct connecting the furnace with the preheating device) and one or two cyclones.

Alternatively, using existing equipment, the production of linker can be significantly increased at little cost and without significantly increasing fuel consumption per ton of clinker product.

Embodiments of the present invention are listed below.

(1) comprising a furnace, a cyclone-type preheating device, and a combustion chamber disposed in the path of the treated material between a last cyclone and a penultimate cyclone of the preheating device; an auxiliary cyclone disposed in the path of the material between the penultimate cyclone of the furnace and the combustion chamber, through which at least a portion of the smoke exiting the furnace passes; and, in some cases, dry cement manufacturing equipment, characterized in that it collects residual smoke from the furnace.

(2) the auxiliary cyclone can be replaced by a group of cyclones arranged in series in the path of the material through which the smoke from the furnace passes continuously so as to provide countercurrent heat exchange; Equipment listed in section.

(3) Clause 1 or 2, characterized in that the entire smoke from the furnace passes through the one or more auxiliary cyclones, and the preheating device receives only smoke from the combustion chamber. Equipment listed in section.

(4) The equipment according to claim 1, 2 or 3, characterized in that it includes a waste heat boiler heated by smoke emitted from the one or more auxiliary cyclones.

(5) including a clinker cooling system, wherein a portion of the hot air exiting the cooling system mixes with smoke exiting from the one or more auxiliary cyclones, and the mixture is used as a heating fluid in the waste heat boiler; 4. The equipment according to item 4, characterized in that:

(6) The first method includes an indirect heat exchanger that is heated by the smoke emitted from the one or more auxiliary cyclones and serves to reheat the secondary air in the combustion chamber. Equipment described in Section 2, Section 2, or Section 3.

(7) The equipment according to item 6, characterized in that it includes a clinker cooling device and includes a waste heat boiler heated by hot air coming from the cooling device.

(8) 1 of the material coming out of the last cyclone of the preheating device.
2. Installation according to claim 1, characterized in that part of the combustion chamber recirculates the combustion chamber.

[Brief explanation of drawings]

1 to 4 are schematic diagrams of an installation according to the invention. 1 to 4, 24, 50, 52...Cyclone,
10...Tubular rotary furnace, 12...Clinker cooling device, 14, 16, 18, 20, 26.
...Duct, 22...Ventilation device, 28.
...Boiler, 30...Burner, 40...
...Combustion chamber, 42...Pipe, 54...
·Heat exchanger.

Claims (1)

[Claims] 1 a furnace, a cyclone-type preheating device, and a combustion chamber arranged in the path of the treated material between the last and penultimate cyclones of the preheating device; an auxiliary cyclone disposed in the path of the material between the second cyclone and the combustion chamber, through which at least a portion of the smoke exiting the furnace passes; In some cases, dry cement manufacturing equipment is characterized by collecting residual smoke from the furnace.