JP2001165507A - High temperature air generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high temperature air generating device to suppress the occurrence of an excess combustion air ratio, recover heat heretofore thrown as a sensible heat, and improve heat-exchange efficiency. SOLUTION: A heat resisting flame stabilizing member 17 having high thermal capacity is disposed in a position situated right downstream from a burner 1, and a heat transfer tube 19 of which a boiler 18 consists is disposed in a position situated downstream from the heat resisting flame stabilizing member 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-temperature air generator.

[0002]

2. Description of the Related Art Generally, as shown in FIGS. 6 and 7, a conventional high-temperature air generator mixes a fuel injected from a burner 1 with combustion air and burns the mixture, thereby converting a high-temperature combustion gas into ceramics. After the heat storage element 2 is heated by flowing through the heat storage element 2, a heat storage type air heater 3 that generates high-temperature air by flowing air through the heat storage element 2 is provided in parallel, During the heating process of the regenerator 2 in the regenerative air heater 3, the process of generating high-temperature air in the other regenerative air heater 3 is performed, and during the process of generating high-temperature air in one regenerative air heater 3, The operation of the regenerative air heater 3 is alternately switched so as to continuously generate high-temperature air so that the regenerative air heater 3 performs the heating step of the regenerator 2 in the regenerative air heater 3. I have.

Each of the burners 1 has a three-way switching valve 4
The fuel supply branch line 6 connected to the fuel supply line 5 is connected by switching, and the combustion chamber 7 of the regenerative air heater 3 to which the burner 1 is connected is burned by switching the three-way switching valve 8, respectively. A combustion air supply branch line 10 connected to a supply air supply line 9 is connected to the regenerator 2 side of the regenerative air heater 3 by switching a four-way switching valve 11 to an air introduction line 12 or an air introduction line 12. An introduction / exhaust line 14 connected to the exhaust line 13 is connected.

A required portion in the middle of the regenerative air heater 3 is communicated by a communication path 15.
Outflow path 16 leading to a gasifier not shown
Is formed, and the generated high-temperature air is supplied to the gasifier or the like from the outlet path 16.

In the high-temperature air generator as described above,
With the three-way switching valve 4, the three-way switching valve 8 and the four-way switching valve 11 switched to the positions shown in FIG. 6, respectively, fuel is transferred from the fuel supply line 5 to the three-way switching valve 4 and one of the fuel supply branch lines 6. The combustion air is supplied from the combustion air supply line 9 through the three-way switching valve 8 and the one combustion air supply branch line 10 while being supplied to the burner 1 of one regenerative air heater 3 and injected therethrough. One regenerative air heater 3
When the fuel is supplied to the wind box 7, the fuel injected from the burner 1 and the combustion air are mixed and burned, and the high-temperature combustion gas passes through the heat storage body 2 of one regenerative air heater 3, After heating the heat storage body 2, the heat storage body 2 is discharged from one of the introduction / discharge lines 14 to the outside via the four-way switching valve 11 and the exhaust line 13.

In the state shown in FIG. 6, the required time (for example,
After the elapse of about 30 [sec], the heat storage body 2 of one of the heat storage air heaters 3 has reached a required temperature (for example, 1200 to 130).
0 [° C.]), the three-way switching valve 4, the three-way switching valve 8, and the four-way switching valve 11 are respectively switched from the position shown in FIG. 6 to the position shown in FIG. 12 flows through the four-way switching valve 11 and one of the introduction / discharge lines 14 to the heated one heat storage body 2, whereby about 1000
High-temperature air of about [° C.] is generated and supplied from the communication path 15 to the gasifier (not shown) via the outlet path 16.

During this time, the fuel is supplied from the fuel supply line 5 to the burner 1 of the other regenerative air heater 3 via the three-way switching valve 4 and the other fuel supply branch line 6, and is injected there. Is supplied from the combustion air supply line 9 to the wind box 7 of the other regenerative air heater 3 via the three-way switching valve 8 and the other combustion air supply branch line 10, and the fuel injected from the burner 1 And combustion air are mixed and burned, and the high-temperature combustion gas is supplied to the other regenerative air heater 3.
After heating the heat accumulator 2 and heating the heat accumulator 2, the heat is discharged from the other introduction / discharge line 14 to the outside via the four-way switching valve 11 and the exhaust line 13, and the state shown in FIG. When a required time (for example, about 30 [sec]) elapses and the heat storage body 2 of the other regenerative air heater 3 reaches a required temperature (for example, about 1200 to 1300 [° C.]), the three-way switching valve is used. 4 and 3 way switching valve 8 and 4 way switching valve 11
Are switched from the position shown in FIG. 7 to the position shown in FIG. 6 again, and air flows from the air introduction line 12 to the four-way switching valve 11 and the other introduction / discharge line 1.
4 through the other heat storage element 2 which is heated, thereby generating high-temperature air of about 1000 [° C.]. Etc., and thereafter, the same operation as described above is repeatedly performed, and the supply of high-temperature air is continuously performed.

[0008]

In the case of the conventional high-temperature air generator as described above, when fuel is burned with a normal theoretical air amount, the adiabatic flame temperature rises to nearly 2000 [° C.], The combustion temperature of about 1400 [° C.] is sufficient to obtain the high-temperature air of about 1000 [° C.] in addition to shortening the life of the heat storage body 2. At present, air is supplied to the wind box 7 of the regenerative air heater 3 to perform combustion, or the air is burned with a moderate excess of air to release heat from the combustion part casing. When the combustion air which becomes excessively large is used or heat is radiated, the heat exchange efficiency is only about 60 to 65 [%], and the efficiency is poor.

In view of such circumstances, the present invention provides a high-temperature air generator capable of suppressing excess combustion air, recovering heat previously discarded as sensible heat, and improving heat exchange efficiency. It is intended to provide.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a method of mixing a fuel injected from a burner and combustion air, burning the mixture, and flowing a high-temperature combustion gas through the regenerator to heat the regenerator. By circulating air through the heat storage body, a regenerative air heater that generates high-temperature air is provided in parallel,
During the heating process of the regenerator in one regenerative air heater, the process of generating high-temperature air in the other regenerative air heater is performed, and during the process of generating high-temperature air in one regenerative air heater, the other In a high-temperature air generator configured to generate high-temperature air continuously by alternately switching the operation of the regenerative air heaters so that the heat storage element is heated in the regenerative air heater, the device is disposed immediately downstream of the burner. And a heat transfer tube forming a boiler is disposed downstream of the heat-resistant flame-holding member at a position downstream of the heat-resistant flame-holding member. .

In the high-temperature air generator, the steam generated in the heat transfer tube may be mixed with the air flowing through the heat storage unit.

In the high-temperature air generator, the heat-resistant flame-holding member may be formed of a ceramic heat-resistant material.

According to the above means, the following effects can be obtained.

In the regenerative air heaters arranged side by side,
The fuel injected from the burner of one regenerative air heater and the combustion air are mixed and burnt, and the high-temperature combustion gas flows through the regenerator of one regenerative air heater to heat the regenerator. After that, switching is performed, the fuel injected from the burner of the other regenerative air heater and the combustion air are mixed and burnt, and the high-temperature combustion gas is stored in the regenerator of the other regenerative air heater. The heat accumulator is heated by flowing through the heat accumulator, and the heating process of the heat accumulator in one heat accumulating air heater and the heating process of the heat accumulator in the other heat accumulating air heater are alternately repeated,
During the heating process of the regenerator in the other regenerative air heater, air is circulated through the heated regenerator of the one regenerative air heater to generate high-temperature air. During the heating process of the regenerator in the above, air is circulated to the regenerator of the other heated regenerative air heater to generate high-temperature air, thereby generating high-temperature air continuously.

Here, a heat-resistant flame holding member having a large heat capacity is provided immediately downstream of the burner, and a heat transfer tube forming a boiler is provided downstream of the heat-resistant flame holding member. Therefore, even if the excess rate of combustion air supplied to the regenerative air heater is reduced to about the same level as that of a normal boiler, the excess heat generated at that time increases the temperature of the heat-resistant flame holding member. And recovered in the form of steam generation in heat transfer tubes,
The heat exchange efficiency can be improved, and the temperature of the heat storage body of the regenerative air heater can be prevented from rising more than necessary.

If the heat-resistant flame-holding member is not disposed immediately downstream of the burner and only the heat transfer tube forming the boiler is disposed downstream of the burner, the non-combustion-side heat storage type When the fuel is injected again from the burner of the air heater and burned, the temperature around the burner may decrease due to the absorption of heat by the heat transfer tube, and combustion may become unstable. Since a heat-resistant flame-holding member having a large heat capacity is disposed immediately downstream, the heat-resistant flame-holding member suppresses a temperature drop around the burner of the regenerative air heater on the non-combustion side and stabilizes combustion. It becomes possible.

When the steam generated in the heat transfer tube is mixed with the air flowing through the heat accumulator, the content of the steam in the high-temperature air is increased. This leads to an increase in gasification efficiency in the gasifier.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 4 show an embodiment of the present invention. In the drawings, the parts denoted by the same reference numerals as those in FIGS. 6 and 7 represent the same parts. This is similar to the conventional one shown in FIGS. 6 and 7, but the feature of the illustrated example is that, as shown in FIGS. 1 to 4, a heat-resistant flame holding member having a large heat capacity is provided immediately downstream of the burner 1. And a boiler 18 at a position downstream of the heat-resistant flame-holding member 17.
In that a heat transfer tube 19 that forms

A steam line 2 extending from a steam drum 20 of a boiler 18 in which steam generated in the heat transfer tube 19 is collected.
1 is connected to the air introduction line 12,
Is generated from the steam drum 20 of the boiler 18 through the steam line 21 to the air introduction line 12 and mixed with the air flowing through the heat storage body 2.

As shown in FIG. 3, a large number of the heat-resistant flame holding members 17 are juxtaposed at a required interval as shown in FIG. 3, and each of them is, for example, as shown in FIG.
It is formed of a ceramic heat-resistant material such as a hollow alumina tube. Note that the temperature conditions are severe, and
In the case where there is a possibility of melting of the cooling medium, as shown in FIG. 5, the heat-resistant flame holding member 17 may be made to penetrate a cooling pipe 22 through which a cooling medium flows.

Next, the operation of the illustrated example will be described.

With the three-way switching valve 4, three-way switching valve 8, and four-way switching valve 11 switched to the positions shown in FIG. 1, fuel is supplied from the fuel supply line 5 to the three-way switching valve 4 and one fuel supply branch line. 6, the combustion air is supplied from the regenerative air heater 3 to the burner 1 of the regenerative air heater 3 and injected therefrom, while the combustion air is supplied from the combustion air supply line 9 to the three-way switching valve 8 and the one combustion air supply branch line 10. When the fuel is supplied to the wind box 7 of one regenerative air heater 3 through the air, the fuel injected from the burner 1 and the combustion air are mixed and burnt, and the high-temperature combustion gas is heated by the one regenerative air heater. After passing through the heat storage unit 2 of the vessel 3 and heating the heat storage unit 2, the heat storage unit 2 is discharged from one introduction / discharge line 14 to the outside via the four-way switching valve 11 and the exhaust line 13.

Here, a heat-resistant flame holding member 17 having a large heat capacity is disposed immediately downstream of the burner 1, and a heat transfer tube forming a boiler 18 is provided downstream of the heat-resistant flame holding member 17. 19, the regenerative air heater 3
Even if the excess rate of the combustion air supplied to the wind box 7 is reduced to about 5 to 10% similarly to a normal boiler, the excess heat generated at that time is reduced by the heat-resistant flame-holding member 17. And the heat exchange efficiency is increased to about 85%, and the temperature of the heat storage body 2 of the heat storage type air heater 3 is also increased to 1200 to 100%. It is suppressed to about 1300 [° C.] and does not rise more than necessary.

In the state shown in FIG. 1, the required time (for example, 30
[Sec], the three-way switching valve 4, three-way switching valve 8, and four-way switching valve 11 are switched from the position shown in FIG. 1 to the position shown in FIG. The heat is passed through the heated one heat storage unit 2 through the valve 11 and the one introduction / discharge line 14, thereby generating high-temperature air of about 1000 [° C.]. After that, it is supplied to a gasifier not shown.

During this time, fuel is supplied from the fuel supply line 5 to the burner 1 of the other regenerative air heater 3 via the three-way switching valve 4 and the other fuel supply branch line 6, and is injected therewith. Is supplied from the combustion air supply line 9 to the wind box 7 of the other regenerative air heater 3 via the three-way switching valve 8 and the other combustion air supply branch line 10, and the fuel injected from the burner 1 And combustion air are mixed and burned, and the high-temperature combustion gas is supplied to the other regenerative air heater 3.
After passing through the heat storage body 2 and heating the heat storage body 2, the heat is discharged from the other introduction / discharge line 14 to the outside through the four-way switching valve 11 and the exhaust line 13. Immediately downstream, a heat-resistant flame holding member 17 having a large heat capacity is provided.
Is provided, and a heat transfer tube 19 forming a boiler 18 is provided at a downstream position of the heat-resistant flame holding member 17, so that the heat transfer tube 19 is supplied to the wind box 7 of the regenerative air heater 3. Even if the excess rate of the combustion air is reduced to about 5 to 10% as in a normal boiler, the excess heat generated at that time will increase the temperature of the heat-resistant flame-holding member 17 and the heat transfer tube 19. Recovered in the form of steam generation, with a heat exchange efficiency of 85%
Temperature, and the temperature of the heat storage body 2 of the heat storage type air heater 3 is also 1200 to 1300 [° C.].
The time required in the state shown in FIG. 2 (for example,
After a lapse of about 30 [sec], the three-way switching valve 4, the three-way switching valve 8, and the four-way switching valve 11 are respectively switched from the position shown in FIG. 2 to the position shown in FIG. Through the four-way switching valve 11 and the other introduction / discharge line 14, the heat is circulated to the other heated heat storage body 2, whereby about 1000
High-temperature air of about [° C.] is generated and supplied to a gasifier (not shown) from the communication path 15 through the outlet path 16. Thereafter, the same operation as described above is repeated, and the high-temperature air is continuously produced. Feeding takes place.

If the heat-resistant flame-holding member 17 is not disposed immediately downstream of the burner 1 and only the heat transfer tube 19 forming the boiler 18 is disposed downstream of the burner 1, When it is attempted to inject fuel again from the burner 1 of the regenerative air heater 3 on the combustion side to burn the fuel, the temperature around the burner 1 decreases due to the heat absorption by the heat transfer tube 19, and the combustion becomes unstable. Burner 1
A heat-resistant flame-holding member 17 made of a ceramic heat-resistant material such as an alumina tube having a large heat capacity is disposed immediately downstream of the heat-storage air-heater 3 on the non-combustion side. Of the burner 1 is suppressed, and the combustion can be stabilized.

On the other hand, the steam generated in the heat transfer tube 19 is
The steam is guided from the steam drum 20 of the boiler 18 to the air introduction line 12 via the steam line 21 and mixed with the air circulated through the heat storage unit 2 to increase the steam content in the high-temperature air. When air is supplied to the gasifier, it leads to an increase in gasification efficiency in the gasifier.

In this way, the excess air for combustion can be suppressed, and the heat previously discarded as sensible heat can be recovered and the heat exchange efficiency can be improved. By mixing with high-temperature air supplied to the apparatus, gasification efficiency in the gasification apparatus can be improved.

The high-temperature air generator of the present invention is not limited to the above-described example, but may be used for other purposes instead of mixing the steam generated in the heat transfer tube into the air flowing through the heat storage body. It goes without saying that various changes may be made without departing from the gist of the present invention, such as that the present invention may be used.

[0031]

As described above, according to the high-temperature air generator of the present invention, the excess air ratio for combustion can be suppressed, and the heat previously discarded as sensible heat can be recovered, and the heat exchange efficiency can be improved. If the steam generated by heat recovery is mixed with high-temperature air and supplied to the gasifier, the gasification efficiency of the gasifier can be improved. An excellent effect of obtaining can be achieved.

[Brief description of the drawings]

FIG. 1 is an overall schematic configuration diagram of an example of an embodiment of the present invention, showing a state in which one burner is burned.

FIG. 2 is an overall schematic configuration diagram of an example of an embodiment of the present invention, showing a state where the other burner is burned.

FIG. 3 is a view taken in the direction of arrows III-III in FIG. 1;

FIG. 4 is a cross-sectional view of the heat-resistant flame holding member,
It is an IV section equivalent view.

FIG. 5 is a cross-sectional view illustrating a modification of the heat-resistant flame holding member.

FIG. 6 is an overall schematic configuration diagram of a conventional example, showing a state in which one burner is burned.

FIG. 7 is an overall schematic configuration diagram of a conventional example, showing a state in which the other burner is burned.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner 2 Heat storage body 3 Heat storage air heater 17 Heat-resistant flame holding member 18 Boiler 19 Heat transfer tube

Claims (3)

[Claims] The fuel injected from a burner and combustion air are mixed and burned, and high-temperature combustion gas is passed through the heat accumulator to heat the heat accumulator and then distribute air to the heat accumulator. By doing so, a regenerative air heater that generates high-temperature air is provided in parallel, and during the heating process of the regenerator in one regenerative air heater, the process of generating high-temperature air in the other regenerative air heater is performed. And, during the process of generating high-temperature air in one regenerative air heater, the heating process of the heat storage body in the other regenerative air heater is performed,
In a high-temperature air generator configured to generate high-temperature air continuously by alternately switching the operation of the regenerative air heaters, a heat-resistant flame holding member having a large heat capacity is disposed immediately downstream of the burner, A high-temperature air generator, wherein a heat transfer tube forming a boiler is disposed downstream of the heat-resistant flame-holding member. 2. The high-temperature air generator according to claim 1, wherein the steam generated in the heat transfer tube is mixed with air flowing through the heat storage body. 3. The high-temperature air generator according to claim 1, wherein the heat-resistant flame holding member is formed of a ceramic heat-resistant material.