JPS61242936A - Multistage preheating apparatus for cement raw material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an improvement in a preheating device for cement raw materials.

[Conventional technology]

Conventionally, this is generally used as a preheating device for cement raw materials.

NSP kiln method is adopted.2. The contents include the mechanism, structure, and performance of this type of preheating device.

The system was basically adopted as is without elucidation of theoretical and rational considerations, and the path system for hot gas and raw cement was a three-stage series.

[Problem that the invention seeks to solve]

As mentioned in the above-mentioned prior art, in the conventional method,
The calorific value of the heat source hot gas is not utilized very effectively, and to be more specific, the temperature of the heat source incoming gas is 840°C to 88°C.
Compared to 0°C, the temperature of exhaust gas is 350°C to 400°C,
Considering the temperature required to prevent the dew point of 502 gas in the exhaust gas, this temperature is higher than necessary, and therefore, more heat than necessary is released without being utilized.
For this reason, the raw materials that are normally input at a temperature of 60°C are separately analyzed based on thermal engineering theory, and the temperature of the discharged products is about 560°C, not higher than 600°C.

Heating of raw materials according to the mechanism and structure of the raw material preheating device.

Due to the above-mentioned low temperature increase performance, the fuel consumption of the cement manufacturing equipment plant as a whole increases, and the size and capacity of the equipment increase more than necessary, and so on.
The conventional NSP kiln system has many problems that need to be improved and developed.

[Means for solving problems]

The present invention has been made in view of the above circumstances.

This will be explained with reference to FIG. 1, which shows an embodiment of the present invention.

The hot gas is 10
When the 0% calcination reaction is completed, the hot gas at a temperature of 900°C that is inevitably generated and discharged according to thermal engineering theory is used as the incoming heat source hot gas, and the hot gas at this temperature is used for heat exchange with the raw material. The temperature of the exhaust gas decreases without losing heat, and the temperature of the exhaust gas when it is discharged is:

Considering the temperature to prevent the dew point of the S02 gas contained therein, the minimum temperature that is practically acceptable is 200.
℃, the raw material is input in a humid state of 60℃, which is the same as the normal temperature, and is gradually heated while exchanging heat with high-temperature hot gas. The material temperature is 750°C, which is very close to the thermal engineering theoretical value of 800°C for the calcining reaction under hot gas conditions.
Basically, the hot gas and the raw material are heated and raised to a temperature of .

When the material is finally discharged, the temperature of the raw material is 750°C, and the temperature of the exhaust gas is 200°C.

The present invention has both structure and performance. However, detailed theoretical content based on the correlation between the hot gas composition and its physical properties at each stage, as well as the content of calculations, etc., will be omitted, and the temperature relationship between the hot gas and raw materials at each stage will be described below. and.

In the first stage passage system, the temperature of the input raw material is 60℃, the temperature of the exhaust gas is 200℃, and the temperature of the raw material discharged is 200℃ of the exhaust gas temperature.
When the temperature is 180℃ which is 20℃ lower than ℃.

The temperature of the incoming hot gas is calculated to be 350° C., and based on this theory, drying, heating, and temperature raising phenomena of the raw materials are performed in this system. In the figure, A is a part corresponding to the main body of the preheating device, and A-1 to A-5 are parts corresponding to the passage system through which hot gas and raw materials pass in a mixed manner.
It is a 5-stage system connected at ~C5.

In the second stage passage (pass) system, the temperature of the input raw material is 180°C, the exhaust gas temperature is 350°C, and therefore, when the temperature of the raw material discharged is 340°C, the temperature of the incoming hot gas is The calculated value is 480°C.

In this system, only the raw material is heated and its temperature is increased.

In the third stage passage system, the temperature of the input raw material is 340°C, and the temperature of the exhaust gas is 480°C.

Therefore, based on the calculation that when the temperature of the discharged raw material is 470°C, the temperature of the incoming hot gas is 600°C, only the heating and temperature raising of the raw material is performed in this system.

In the fourth stage passage system, the temperature of the input raw material is 470°C, and the temperature of the exhaust gas is 600°C.

Therefore, when the temperature of the raw material to be discharged is 590°C.

The temperature of the incoming hot gas is 770°C, and only the heating and temperature raising of the raw material is performed within this system.

In the fifth stage passage system, the high temperature of the input raw material is 590°C, and the temperature of the exhaust gas is 770°C.

Therefore, the temperature of the raw material to be discharged is 75°C compared to 770°C.
When the proper product temperature is 0°C, this product temperature is the final target temperature of 750°C by heating the raw material.

In this case, the temperature of the incoming hot gas is calculated to be 900° C. appropriately, and the incoming hot gas at this temperature is the incoming hot gas itself according to the present invention.

As is clear from the above calculation results, the high temperature 900
In order to heat and raise the temperature of two raw materials with a temperature of 60°C while the temperature of the hot gas at ℃ decreases through heat exchange with the raw material, and the temperature of the exhaust gas reaches 200°C, to reach the final target temperature of 750°C, The passage system for heat exchange should be a five-stage system, and the present invention adopts a five-stage system for the passage system based on thermal engineering calculations separately performed.

[Effect]

According to the above structure, as shown in FIG. 1 showing an embodiment of the present invention, the raw material is charged at 60 DEG C. at the raw material input duct port 3, and in the first stage structure section A-1.

As mentioned above, when the raw material temperature is 60°C and the discharged raw material is 180°C, the temperature of one input hot gas is calculated to be 350°C.

In the second stage structure section A-2, when the input raw material is 180°C and the exhaust gas temperature is 340°C, the input hot gas is 480°C.
Next door.

In the third stage structure section A-3, the input raw material temperature was 340°C.
, when the exhaust gas temperature is 470°C, the incoming hot gas is 60°C.
It becomes 0℃.

In the fourth stage structure section A-4, the input raw material temperature was 470
℃, the exhaust gas temperature is 600℃, so the temperature of the discharged raw material is 590℃.
If set to 9°C, the incoming hot gas temperature will be 770°C.

In the fifth stage structure section A-5, when the input raw material is set at 590°C and the exhaust gas temperature and therefore the discharged raw material temperature is set at 750°C with respect to the exhaust gas temperature of 770°C, the temperature of the 2nd product is determined by heating the raw material and raising the temperature. The target temperature is 750°C, and in this case, the calculated value of the incoming hot gas temperature is 900°C, and while this 900°C hot gas cools down through heat exchange with the raw material, and the exhaust gas temperature reaches 200°C, the raw material at a temperature of 60°C is At the same time, the final target of 75
It is kept at 0℃. In addition, as mentioned above, at each stage.

In the first stage structure section A-1, raw materials are dried.

Heating and temperature increase are performed.

In the second stage structure section A-2, heating and temperature raising are performed.

In the third stage structure section A-3, heating and temperature raising are performed.

In the fourth stage structure section A-4, heating and temperature raising are performed.

In the fifth stage structure section A-5, the action of decomposing and releasing crystal water contained in the raw material is performed.

〔Example〕

An embodiment of the present invention will be described based on the drawings.

In the figure, A indicates a part corresponding to the main body of the raw material preheating device, and A-1 to A-5 indicate parts corresponding to the inside of the passage system.

Each stage of the five-stage system is connected to each other by communication ducts) C+ to C5, and B1 to BS are cyclone collectors.

1 is the inlet duct for hot gas, 2 is the exhaust duct for exhaust gas, 3 is the raw material input duct, 4 is the discharge duct for heated and heated raw materials, the arrow → indicates the hot gas, and the - symbol for each raw material. Indicates flow direction. The phenomenon between the hot gas and the raw material due to the mechanism, structure, performance, etc. of the raw material preheating device in the 5\lt floor passage system will be explained for each stage.

Inside the A-1 system, as described in the first stage passage system, there are 9 raw materials in a wet state with a temperature of 60°C, and the raw material input duct port 3 provided at the base of the first duct CI. The moisture that has dried and adhered to the gas is completely released, and the 9 parts are discharged from the exhaust gas exhaust duct port 2 at a temperature of 180°C as anhydrous products, and are then introduced into the A-2 system, and the hot gas is heated to a temperature of 350°C. 1st in °C
The material is introduced into the duct C1, and the raw material is heated, raised in temperature, and dried.

The raw material is discharged from the exhaust duct 2 at a temperature of 200° C. together with the moisture released from the raw material. In this case, the first cyclone collector B1 is provided in the first stage structure A-1, and this first cyclone collector B1 is formed from two cylindrical bodies and a funnel-shaped bottom, and the top part is provided with an exhaust gas exhaust duct opening 2, the body is connected to a first duct C1, and the bottom is connected to a first raw material transport pipe.

This first cyclone collector B collects ultrafine particles in the raw material.
~3% of the particles cannot be separated and collected from the hot gas and are released with the exhaust gas, but the entire amount of the remaining raw material is collected and, as described above, flows into the base of the duct C2 in the A-2 system. Injected.

In this way, the drying, heating, and temperature rising phenomena of the raw materials are performed in this system as described above.

In the A-2 system, as mentioned above in the stage passage system, the raw material is introduced into the base of the second duct C2 at a temperature of 180°C, and in this system there is a first cyclone trap. Collector B
A second cyclone collector B2 having the same structure as 1 is provided, the top of which connects the first duct C1, and the second duct C2 is connected to the body of the first cyclone collector B2.
A second raw material transport pipe D2 is connected to the bottom, and its tip is opened into the base of the third duct C3.

The entire amount of the above-mentioned raw material is separated and collected from the ripe gas by the second cyclone collector B2, and the temperature of 9 items is 34.
At 0° C., it is introduced into the base of the third duct C3 in the A-3 system. The temperature of the hot gas is 480 from the inlet of the first duct) C+.
The air enters at a temperature of 350°C and is discharged from the exhaust gas outlet duct 2 at a temperature of 350°C, and the remaining raw material is transferred to the third duct in the A-3 system (C3).
will be put into the

That is, in this system, the raw material is heated as described above.

Only the temperature is increased.

A third cyclone collector B3 having the same structure as the above-mentioned cyclone collector is installed in the A-3 system, and a second cyclone collector B3 is installed at the top of the third cyclone collector B3.
A third duct C3 is connected to the body, a third raw material transport pipe D3 is connected to the bottom, and its tip opens into the base of the fourth duct C4. This system corresponds to the third stage passage route (bus) system described above, and is A-2.
As in the system, the entire amount of raw material is separated from the hot gas by the third cyclone collector B3 in each system.

It is collected and sent to the next process.

In the A-4 system, the fourth cyclone collector B is installed as described above.
The base of the third duct (C3) is connected to the top, and the fourth duct (C4) is connected to the body of the -4 system, which also corresponds to the fourth stage passage (bus) system. In this system, raw materials are heated in the same way as above.

The temperature is raised, and the total amount of the input raw material is separated from the hot gas by the first Ikron collector B4 in this system.
After being collected, it is fed into the next process.

Therefore, in these systems, the raw material has a temperature of 340°C - 4470°C - 590°C and is introduced into the base of the fifth duct C5 in the A-5 system, and the hot gas is transferred to the A-5 system. 5
The temperature from inside the system is 770℃-600℃-480℃ and A
-2 is introduced into the system. If the respective flows are illustrated as raw material-9 during hot gas as described above, each communication passage duct is connected to C.
It flows in the direction of 5-C4-C3-C2 and is introduced into the A-2 system.

The A-5 system corresponds to the fifth stage passage system. Similarly to the above, a fifth cyclone collector Bs is provided in this system, the base of the fourth duct C4 is connected to the top, the fifth duct C5 is connected to the body, and the elevator Connect the hot raw material discharge duct port 4. Furthermore, the fifth duct C
5, the fourth raw material transport pipe D4 is opened as described above, and the tip of the base forms the hot gas intake duct opening 1.

In such an A-5 system, there is a reaction phenomenon in which water of crystallization in the raw material is decomposed and released, as well as heating of the raw material.

Basically, the temperature rise phenomenon occurs, and the raw material temperature is 590℃.
℃ into the base of the fifth duct C5, and while passing through this duct, it is heated and the temperature rises, and when the temperature of the two products reaches 600℃, the decomposition and release of crystal water starts and is completed. I took it as a thing. However, theoretically, the raw material temperature should be 450℃~600℃.
It is said that water of crystallization is separated and released at a temperature of 600°C, but in this case, in consideration of ease of calculation, this reaction was assumed to start and complete at a maximum product temperature of 600°C. After that, it is further heated,
The temperature rises.

As already mentioned, the suitability for the final purpose is 5th when the product temperature is 750℃.
The total amount of raw material is determined by the cyclone collector BS.

It is separated from the hot gas, collected and discharged, and then sent to the calcining reactor (
(not shown). Also, the heat source input hot gas is 900
The fifth duct C5 in this system from the calcination reactor at a temperature of °C
After completing the intended treatment on the raw material in a rational and appropriate manner, it is discharged from the fifth cyclone collector BS at a temperature of 770°C, containing the water content of the crystallized water from the raw material, and 4th duct in the -4 system) is introduced into C4. still,
The raw material input duct port 3 is opened into the base of the first duct CI.

〔Effect of the invention〕

As described above, the present invention can be used as a stand-alone device.

If applied to the conventional NSP kiln system, the fuel consumption will be further reduced (1) and saved, and as described above, the mechanism, structure, performance, etc. of the present invention will be improved (2) in a series of relationships with the present invention. Therefore, theoretically and based on a comprehensive equipment plant for cement manufacturing with new and rational improvements, the unit fuel consumption would be 75 to 80xlO' (kcal/l-clinker) compared to the conventional NSP kiln system. 65 x 10' (kcal
/ T-clinker], and the effects are extremely significant and significant, including energy savings in operation due to the smaller capacity of related equipment.

Furthermore, by adopting the present invention, the fuel consumption of the rotary furnace for cement firing can be further reduced compared to the conventional method, and as a result, the amount of NOx generated can be reduced, which improves environmental hygiene. The effect is also ascension.

[Brief explanation of the drawing]

FIG. 1 is a detailed explanatory diagram of the present invention. A... Part corresponding to the raw material preheating device main body, A-1... First stage structure part, A-2... Second stage structure part, A-3...
Third stage structure part, A-4...Fourth stage structure part, A-5
...Fifth stage structure part, 1... Hot gas intake duct opening, 2... Exhaust gas discharge duct opening, 3... Raw material input duct opening. 4... Discharge duct opening for heated raw material, BI... First cyclone collector +82... Second cyclone collector, B3
...Third cyclone collector +84...Fourth cyclone collector, BS...Fifth cyclone collector +CI...
・First duct, C2...second duct, C3...third
duct. C4... 4th duct F*Cs... 5th duct + DI.
...First raw material transport pipe, D2...Second raw material transport pipe +03
...Third raw material transport pipe, D4...Fourth raw material transport pipe, =
6... Direction of flow of hot gas, - Direction of flow of raw material. Applicant Ube Jitsugyo Engineering Consultant Co., Ltd.

Claims (1)

[Claims] As a preheating device for cement raw materials, it consists of five stages of structure from an upper structure to a lower structure, and the first stage structure includes a cylindrical body and an inverted conical funnel. A first cyclone collector consisting of a shaped bottom part is installed, an exhaust gas duct opening is provided at the top part facing upward, a first duct is connected to the body part, and the raw material is placed in the base part of the first duct. The input duct opening is opened, the first raw material transport pipe is connected to the bottom, and the second stage structure section is provided with a second cyclone collector having the same structure as the first cyclone collector, At the top of this
A base tip of the first duct is connected, a second duct is connected to the body, the tip of the first raw material transport pipe is opened in the base, and a second raw material transport pipe is connected to the bottom of the base. The third stage structure is provided with a third cyclone collector having the same structure as the above-mentioned cyclone collector, the top of which is connected to the base end of the second duct, and the body is connected to the third cyclone collector. A third duct is connected, the tip of the second raw material transport pipe is opened in the base, the third raw material transport pipe is connected to the bottom, and the fourth stage structure has the same as above. A fourth cyclone collector having a structure is provided, the top of which is connected to the base tip of the third duct, the body of which is connected to a fourth duct, and the third raw material transport pipe is connected to the base of the fourth cyclone collector. A fourth raw material transport pipe is connected to the bottom, and a fifth cyclone collector having the same structure as above is provided in the fifth stage structure, and the fourth duct is connected to the top of the fifth cyclone collector. A fifth duct is connected to the body, and the tip of the fourth raw material transport pipe is opened in the base, and a hot gas inlet is connected to the base. A multi-stage preheating device for cement raw materials, which is provided with a duct opening, and a duct opening for discharging the heated raw material at the bottom.