TW201430287A - Burner apparatus and combustion control method for burner apparatus - Google Patents

Abstract

This invention provides a burner apparatus and a combustion control method for burner apparatus. Provided is burner apparatus A1 to A3 which makes a primary combustion air guided by a primary air guidance pipe 11 and a fuel guided into a fuel guidance pipe 12 be combusted in a primary combustion chamber 13, makes a combustion exhaust gas after combustion pass through a first nozzle part 16 so that the gas is ejected into the interior 1a of a furnace 1, and makes a heated secondary combustion air in a regenerative chamber 20 pass through a secondary air guidance pipe 22 and then pass through a second nozzle part 23 near the first nozzle part so that the air is ejected into the interior of furnace, wherein, the first nozzle part is narrowed toward the interior of furnace, and the amount of the fuel of fuel guidance pipe, the primary combustion air of primary air guidance pipe, and the secondary combustion air of secondary air guidance pipe are controlled by the temperature corresponding to the interior of furnace.

Description

Combustion device and combustion control method of combustion device

The present invention relates to a combustion apparatus and a combustion control method of the combustion apparatus. In particular, the combustion apparatus includes: a primary air guiding tube that guides primary combustion air; a fuel guiding tube that is disposed on an inner peripheral side of the primary air guiding tube to guide fuel; and a primary combustion guided by the primary air guiding tube a primary combustion chamber that combusts air and fuel that is guided to the fuel guiding tube; a first nozzle portion that communicates the primary combustion chamber with the inside of the furnace; and a secondary air guide that guides the secondary combustion air heated in the regenerator And a second nozzle portion that discharges the secondary combustion air guided by the secondary air guiding pipe to the inside of the furnace in the vicinity of the first nozzle portion; and when used in a combustion device, corresponds to The temperature inside the furnace is appropriately controlled to control the combustion state, stable combustion performance is obtained from the low temperature region to the high temperature region, and generation of NOx in the high temperature region can be suppressed.

In various industrial furnaces such as a heating furnace that heats a material to be processed, various combustion apparatuses have been used in the past.

Further, in recent years, as disclosed in Patent Documents 1, 2, and the like, a primary air guiding pipe for guiding primary combustion air and a fuel guiding pipe provided on the inner peripheral side of the primary air guiding pipe to guide fuel have been proposed. The primary combustion air guided by the primary air guiding pipe and the fuel guided to the fuel guiding pipe are once burned, and the heat of the combustion exhaust gas inside the furnace is accumulated in the regenerator of the heat storage material, whereby the heat storage is performed. The material is heated by the secondary combustion air, and the secondary combustion air heated by the secondary air guide pipe is introduced into the furnace, and the secondary combustion air and fuel are secondarily burned inside the furnace to effectively utilize the combustion. After the heat of the exhaust gas is burned, a technique for efficient combustion is performed.

Here, in the technique disclosed in Patent Document 1, a primary flame nozzle and a main flame nozzle are provided in the fuel guiding tube, and the fuel discharged from the primary flame nozzle is mixed with the primary combustion air and then ignited by the spark plug to form a primary flame. And mixing the fuel discharged from the main flame nozzle with the primary combustion air, causing the flame to spread from the primary flame to form a main flame inside the furnace, and then guiding the second heating in the regenerator by the secondary air guiding tube The combustion air is sprayed toward the main flame formed inside the furnace to form a main diffusion flame.

However, in the technique disclosed in Patent Document 1, only the main flame is used to rapidly and uniformly heat the inside of the furnace, and the temperature inside the furnace is not sufficiently raised, and the fuel does not spontaneously ignite, as described above. Make When the secondary combustion air is ejected toward the main flame, the fuel cannot be sufficiently burned, so that the main diffusion flame cannot be appropriately formed, so that the combustion becomes unstable, and there is a problem that unburned fuel components remain in the exhaust gas.

Further, the technique disclosed in Patent Document 2 is a primary combustion chamber in which an opening is provided in a furnace forming a main combustion chamber, and a fuel nozzle that discharges fuel to the primary combustion chamber and a primary air supply to the periphery of the fuel nozzle are provided. The air supply path and the secondary air supply path for injecting secondary air heated in the main combustion chamber from the vicinity of the primary combustion chamber, and raising the primary air relative to the primary air and the secondary air when the temperature of the main combustion chamber is low The ratio of the overall amount, the primary fuel surrounds the sprayed fuel to prevent incomplete combustion of the fuel from adhering to the furnace wall, in particular to prevent carbon from adhering to the inner wall of the primary combustion chamber, and on the other hand, the temperature of the main combustion chamber When higher, the ratio of primary air to the total amount of primary air and secondary air is reduced, and the generation of NOx is reduced.

However, the technique disclosed in Patent Document 2 is that in the primary combustion chamber, the primary air guided by the primary air supply path is supplied to the periphery of the fuel discharged from the fuel nozzle and is once burned, so that it is difficult to make the main The temperature of the entire combustion chamber rises rapidly and uniformly, and temperature unevenness is generated in the main combustion chamber. The secondary air is injected from the vicinity of the primary combustion chamber to the main combustion chamber and burned by the secondary air supply path as described above. In the case where the temperature is low, the fuel cannot be sufficiently burned, and the fuel component burned in the exhaust gas does not easily remain, so that the combustion becomes unstable. The problem of grading.

(previous technical literature) (Patent Literature)

(Patent Document 1) Japanese Patent Laid-Open Publication No. 2007-24335

(Patent Document 2) Japanese Patent Laid-Open Publication No. 2010-127525

An object of the present invention is to solve the problems as described above in a combustion apparatus.

That is, the object of the present invention is to appropriately control the combustion state in accordance with the temperature inside the furnace in the case of use in a combustion apparatus, to obtain stable combustion performance from a low temperature region to a high temperature region, and to suppress high temperature regions. NOx generation, the combustion apparatus having: a primary air guiding tube for guiding primary combustion air; a fuel guiding tube provided on an inner peripheral side of the primary air guiding tube to guide fuel; and being guided by the primary air guiding tube a primary combustion chamber for combusting air and fuel to be guided to the fuel guiding tube; a first nozzle portion that communicates the primary combustion chamber with the inside of the furnace; and a secondary combustion air that is heated in the regenerator An air guiding pipe; and a second nozzle portion that discharges the secondary combustion air guided by the secondary air guiding pipe to the inside of the furnace in the vicinity of the first nozzle portion.

In order to solve the above problems, the combustion apparatus of the present invention includes: a primary air guiding pipe for guiding primary combustion air; and a fuel guiding pipe provided on the inner peripheral side of the primary air guiding pipe to guide fuel; a primary combustion chamber in which primary combustion air guided by the primary air guiding pipe and fuel guided by the fuel guiding pipe are combusted; a first nozzle portion that communicates the primary combustion chamber with the inside of the furnace; and is guided to be heated in the regenerator a secondary air guiding pipe for secondary combustion air; and a second nozzle portion that discharges the secondary combustion air guided by the secondary air guiding pipe to the inside of the furnace in the vicinity of the first nozzle portion; the combustion The apparatus is provided with: primary air control means for controlling the guidance of the primary combustion air by the primary air guiding pipe; fuel control means for controlling the guidance of the fuel by the fuel guiding pipe; and control by the foregoing a secondary air control means for guiding the secondary combustion air by the secondary air guiding pipe; and causing the first nozzle portion to be ignited once The blast chamber is contracted toward the inside of the furnace, and the combustion exhaust gas obtained by burning the primary combustion air and the fuel in the primary combustion chamber is ejected to the inside of the furnace at a high speed through the first nozzle portion.

Further, in the combustion apparatus of the present invention, the preliminary air supply means for mixing the preliminary combustion air with the fuel may be provided before the fuel guided by the fuel guiding pipe is guided to the primary combustion chamber, and is provided for A preliminary air control means for controlling supply of preliminary combustion air by the preliminary air supply means.

Here, in the preliminary air supply means, the preliminary combustion air may be supplied to the fuel guiding pipe to mix the fuel and the preliminary combustion air (also referred to as premixing), or in the fuel guiding pipe and the primary air. A preliminary air guiding pipe is disposed between the guiding pipes so that the preliminary combustion air guided by the preliminary air guiding pipe is mixed with the fuel guided by the fuel guiding pipe before being guided to the primary combustion chamber.

Further, the combustion control method of the combustion apparatus of the present invention is switched to the following three combustion states: in the first temperature region where the temperature inside the furnace is low, the first air control means is guided by the primary air control means. The primary combustion air and the fuel guided by the fuel guiding pipe by the fuel control means are combusted in the primary combustion chamber, and the combustion exhaust gas is ejected to the first combustion state inside the furnace at a high speed by the first nozzle portion. In the second temperature region in which the temperature inside the furnace is higher than the first temperature region, the amount of fuel guided by the fuel guiding tube is increased by the fuel control means, and the first combustion state is increased. The secondary combustion air guided by the secondary air guiding means by the secondary air control means is discharged from the second nozzle portion to the inside of the furnace to make the primary combustion air guided by the primary air guiding pipe And the fuel guided by the fuel guiding tube is burned in the primary combustion chamber, and the combustion exhaust gas is passed through the first nozzle portion. High velocity to the interior of the furnace, and the inside of the furnace, the secondary combustion so that the combustion state of the second unburned fuel contained in exhaust gas and combustion air for the combustion; and In the third temperature region in which the temperature inside the furnace is higher than the second temperature region, the primary air control means stops the guidance of the primary combustion air by the primary air control means, and borrows The secondary air control means increases the amount of the secondary combustion air that is discharged from the second nozzle portion to the inside of the furnace by the secondary air guiding pipe, and is guided by the fuel guiding means by the fuel control means. When the amount of fuel is increased, the fuel is discharged from the primary combustion chamber through the first nozzle portion to the inside of the furnace, and the secondary combustion air and the fuel are burned in the third combustion state inside the furnace.

Further, a preliminary air supply means for mixing the preliminary combustion air with the fuel before the fuel guided by the fuel guiding pipe is guided to the primary combustion chamber, and provided for controlling the preliminary air supply means In the combustion control method of the combustion apparatus of the preliminary air control means for supplying the combustion air, the amount of fuel guided by the fuel guiding pipe may be reduced by the fuel control means before the first combustion state, and by The preliminary air supply means mixes the preliminary combustion air with the fuel that is guided to the primary combustion chamber and prepares the combustion.

Further, the second combustion state and the third combustion state may be switched without passing through the first combustion state.

In the combustion apparatus of the present invention and the combustion control method of the combustion apparatus, the primary combustion air guided by the primary air control means by the primary air control means is provided in the first temperature region where the temperature inside the furnace is low. And the fuel guided by the fuel guiding means by the fuel control means is combusted in the primary combustion chamber, and the combustion exhaust gas is discharged into the furnace at a high speed through the first nozzle portion to be in a first combustion state. The inside of the furnace can be quickly and uniformly heated by the stirring effect by the high temperature combustion exhaust gas which is ejected to the inside of the furnace at a high speed by the first nozzle portion.

Further, in the second temperature region in which the temperature inside the furnace is higher than the first temperature region, the amount of fuel guided by the fuel guiding pipe is increased by the fuel control means more than the first combustion state. Further, the secondary combustion air guided by the secondary air guiding means by the secondary air control means is discharged from the second nozzle portion to the inside of the furnace to allow primary combustion guided by the primary air guiding pipe. The air and the fuel guided by the fuel guiding tube are combusted in the primary combustion chamber, and the combustion exhaust gas is ejected to the inside of the furnace at a high speed through the first nozzle portion, and the secondary combustion air and the aforementioned When the unburned fuel contained in the combustion exhaust gas is burned to be in the second combustion state, the environment inside the furnace is stirred without leaving unburned fuel, and the amount of fuel can be increased to improve the combustion efficiency.

Moreover, when a combustion apparatus that heats the secondary combustion air by a heat exchanger or a regenerator that accommodates the heat storage material is used, the efficiency of heat recovery is also Will improve, energy saving effect will also increase.

Further, in the third temperature region in which the temperature inside the furnace is higher than the second temperature region, the primary air control means stops the primary combustion air based on the primary air guiding means, and The amount of the secondary combustion air that is ejected from the second nozzle portion to the inside of the furnace by the secondary air guiding pipe is increased by the secondary air control means, and the fuel guiding means is passed through the fuel guiding means. When the amount of fuel to be introduced is increased, the fuel is ejected from the primary combustion chamber through the first nozzle portion to the inside of the furnace, and when the secondary combustion air and fuel are burned inside the furnace to be in the third combustion state, The fuel ejected to the inside of the furnace and the heated secondary combustion air are appropriately mixed as described above in the uniformly heated furnace, and are burned over a wide range, thereby improving combustion efficiency, and It is also possible to suppress the generation of NOx by suppressing local temperature rise due to local combustion.

As a result, in the combustion apparatus of the present invention and the combustion control method of the combustion apparatus, the combustion state is appropriately controlled in accordance with the temperature inside the furnace, stable combustion performance is obtained from the low temperature region to the high temperature region, and the high temperature can be appropriately suppressed. The production of NOx in the area.

1‧‧‧ furnace

1a‧‧‧Internal

11‧‧‧One air guiding tube

12‧‧‧fuel guiding tube

13‧‧‧One combustion chamber

14‧‧‧ Stabilizer

15‧‧‧Mars plug

16‧‧‧1st nozzle section

17‧‧‧Prepared air guiding tube

17a‧‧‧Preparation and Mixing Department

20 (20A, 20B) ‧ ‧ regenerator

21 (21A, 21B) ‧ ‧ heat storage materials

22 (22A, 22B) ‧ ‧ secondary air guide tube

23(23A, 23B)‧‧‧2nd nozzle section

24 (24A, 24B) ‧ ‧ exhaust exhaust pipe

30‧‧‧fuel supply unit

31‧‧‧Fuel adjustment valve

40‧‧‧Combustion air supply unit

41‧‧‧One air adjustment valve (primary air control means)

42 (42A, 42B) ‧ ‧ secondary air regulating valve (secondary air control means)

43‧‧‧Prepared air supply route (prepared air supply means)

44‧‧‧Prepared air conditioning valve (prepared air control means)

50‧‧‧Exhaust device

51 (51A, 51B) ‧ ‧ exhaust exhaust valve

A1 to A3‧‧‧ burning device

Fig. 1 is a schematic explanatory view of a combustion apparatus according to Embodiment 1 of the present invention.

Fig. 2 is a view showing the use of the combustion apparatus of the first embodiment, in the furnace In the case of the first temperature region where the temperature is low, the state of the first combustion state is burned.

FIG. 3 is a schematic view showing a state in which the second combustion state is burned when the temperature inside the furnace becomes higher than the first temperature region in the combustion apparatus according to the first embodiment. Figure.

Fig. 4 is a schematic view showing a state in which the third combustion state is burned when the temperature inside the furnace becomes higher than the second temperature region in the combustion apparatus of the first embodiment. Figure.

Fig. 5 is a schematic explanatory view showing a combustion apparatus according to a second embodiment of the present invention, in which a fuel is mixed with pre-combustion air and pre-combusted before combustion in the first combustion state.

Fig. 6 is a view showing a combustion apparatus according to the second embodiment, wherein the fuel is mixed with the pre-combustion air and pre-combusted before the combustion in the first combustion state is performed in the first temperature region where the temperature inside the furnace is low. A schematic illustration of the state.

Fig. 7 is a schematic explanatory view showing a state in which the combustion apparatus of the second embodiment is in a first combustion state when the temperature inside the furnace is low, and is burned.

FIG. 8 is a schematic view showing a state in which the second combustion state is burned when the temperature inside the furnace becomes higher than the first temperature region in the combustion apparatus of the second embodiment. Figure.

FIG. 9 is a schematic view showing a state in which the third combustion state is burned when the temperature inside the furnace becomes higher than the temperature range of the third temperature region in the combustion apparatus according to the second embodiment. Figure.

Fig. 10 is a schematic explanatory view showing a combustion apparatus in which the fuel and the preliminary combustion air are mixed and pre-combusted before the combustion in the first combustion state is performed.

Figure 11 is a view showing a combustion apparatus according to the third embodiment, wherein the fuel is mixed with the pre-combustion air and pre-combusted before the combustion in the first combustion state is performed in the first temperature region where the temperature inside the furnace is low. A schematic illustration of the state.

Fig. 12 is a schematic explanatory view showing a state in which the combustion apparatus of the third embodiment is in a first combustion state in which the temperature inside the furnace is low, and is burned.

Fig. 13 is a schematic view showing a state in which the combustion state of the combustion apparatus of the third embodiment is in a second combustion state when the temperature inside the furnace becomes higher than the first temperature region. Figure.

Fig. 14 is a schematic view showing a state in which the third combustion state is burned when the temperature inside the furnace becomes higher than the second temperature region in the combustion apparatus of the third embodiment. Figure.

Hereinafter, a combustion apparatus and a combustion control method of the combustion apparatus according to the embodiment of the present invention will be specifically described based on the drawings. In addition, the combustion control method of the present invention and the combustion control method of the combustion apparatus are not limited to those shown in the following embodiments, and can be appropriately modified without departing from the scope of the invention.

(Embodiment 1)

In the combustion apparatus A1 of the first embodiment, as shown in Fig. 1, a fuel guiding pipe 12 for guiding fuel is provided on the inner peripheral side of the primary air guiding pipe 11 for guiding primary combustion air, and the primary air guiding pipe is provided. 11 and the front end side of the fuel guiding tube 12 are provided with a primary combustion chamber 13 for combusting primary combustion air guided by the primary air guiding pipe 11 and fuel guided by the fuel guiding pipe 12, and for primary combustion air At a position before being guided to the primary combustion chamber 13, a stabilizer 14 is disposed between the aforementioned primary air guiding tube 11 and the fuel guiding tube 12, and is provided to extend into the aforementioned primary combustion chamber 13 through the aforementioned primary air guiding tube 11. Mars plug 15.

Further, the primary combustion chamber 13 is communicated with the inside 1a of the furnace 1 by the first nozzle portion 16, and the first nozzle portion 16 is contracted from the primary combustion chamber 13 toward the inside 1a of the furnace 1.

Further, on both sides of the primary air guiding pipe 11, heat storage chambers 20 (20A, 20B) in which the heat storage materials 21 (21A, 21B) are accommodated are provided in pairs, and are provided for guiding in the respective heat storage chambers 20 (20A, 20A, 20B) The secondary air guiding tubes 22 (22A, 22B) of the heated secondary combustion air are provided in the vicinity of the first nozzle portion 16 by the respective secondary air guiding tubes 22 (22A, 22B) The guided secondary combustion air is discharged to the second nozzle portion 23 (23A, 23B) of the inside 1a of the furnace 1.

Further, a fuel regulating valve (fuel control means) 31 is provided in the middle of guiding the fuel from the fuel supply device 30 to the fuel guiding pipe 12, and the amount of fuel to be guided to the fuel guiding pipe 12 is adjusted by the fuel regulating valve 31. .

Further, a primary air regulating valve (primary air control means) 41 is provided in the middle of guiding the combustion air from the combustion air supply device 40 to the primary air guiding pipe 11, and is adjusted by the primary combustion air adjusting valve 41. The amount of primary combustion air to be directed to the primary air guide tube 11.

Further, a secondary air regulating valve (secondary air control means) 42 (42A, 42B) is provided in the middle of each of the regenerators 20 (20A, 20B) from the combustion air supply device 40, and The secondary air conditioning valves 42 (42A, 42B) are used to adjust the secondary combustion air to be guided to the respective secondary air guiding tubes 22 (22A, 22B) through the respective regenerators 20 (20A, 20B). the amount.

Further, in each of the heat storage chambers 20 (20A, 20B), heat of the combustion exhaust gas inside the furnace 1a is accumulated in the heat storage material 21, and the combustion exhaust gas is discharged from the regenerators 20 (20A, 20B). The exhaust gas discharge pipe 24 (24A, 24B) is provided with an exhaust gas discharge valve 51 (51A, 51B) between each of the exhaust gas discharge pipes 24 (24A, 24B) and the exhaust device 50, and the exhaust gas discharge valve 51 is opened (51A, 51B) The combustion exhaust gas guided from each of the regenerators 20 (20A, 20B) to each of the exhaust gas discharge pipes 24 (24A, 24B) is discharged by the exhaust device 50.

Here, the combustion apparatus A1 of the first embodiment is in the first temperature region where the temperature of the inside 1a of the furnace 1 is low, and as shown in Fig. 2, the combustion air is used by the primary air regulating valve 41. The supply device 40 guides an appropriate amount of primary combustion air to the primary air guide pipe 11, and guides an appropriate amount of fuel from the fuel supply device 30 to the fuel guide pipe 12 through the fuel adjustment valve 31 to pass the aforementioned primary air. The primary combustion air guided to the primary combustion chamber 13 by the pilot pipe 11 and the fuel guided to the primary combustion chamber 13 through the fuel guiding pipe 12 are mixed in the primary combustion chamber 13, and are ignited by the aforementioned spark plug 15 This combustion causes the combustion exhaust gas generated by the combustion to be ejected from the primary combustion chamber 13 toward the inside 1a of the furnace 1 through the first nozzle unit 16 (first combustion state). Further, the opening and closing of the valves 31, 41, 42, and 51 in FIGS. 2 to 4 is an open state in reverse white, and a closed state in black.

When the combustion in the first combustion state is performed, the high-temperature combustion exhaust gas which is burned and expanded in the primary combustion chamber 13 is ejected at a high speed by the first nozzle portion 16 which is contracted toward the inside 1a of the furnace 1 as described above. To the inside 1a of the furnace 1, the inside 1a of the furnace 1 is heated quickly and uniformly by the stirring effect of the high-temperature combustion exhaust gas which is ejected at a high speed. In addition, the "high speed" generally means 80 m/s or more, and when it is ejected in this state, the environment inside the furnace 1 is stirred, and the temperature distribution in the furnace 1 is made uniform.

Further, in the first combustion state, the foregoing secondary air conditioning is turned off. The entire valves 42A, 42B prevent the secondary combustion air from being supplied to the respective regenerators 20A, 20B, and prevent the secondary combustion air from being ejected from the respective secondary air guiding tubes 22A, 22B to the inside 1a of the furnace 1, and closing the aforementioned Each of the exhaust gas discharge valves 51A, 51B prevents the combustion exhaust gas inside the furnace 1 from being supplied into the respective regenerators 20A, 20B by the exhaust device 50, and prevents the combustion exhaust gas from being discharged through the respective exhaust gas discharge pipes 24A, 24B. . Further, although not shown, when the temperature of the inside 1a of the furnace 1 rises to some extent, the exhaust gas discharge valves 51A and 51B may be opened to guide the combustion exhaust gas inside the furnace 1 to the respective regenerators 20A. In 20B, the heat of the combustion exhaust gas is accumulated in each of the heat storage materials 21A and 21B of the respective heat storage chambers 20A and 20B.

Next, in the second temperature region in which the temperature of the inside 1a of the furnace 1 is higher than the first temperature region due to the combustion in the first combustion state, as shown in FIG. 3, the first combustion state is In the same case, the primary combustion air guided to the primary combustion chamber 13 through the primary air guiding pipe 11 and the fuel guided to the primary combustion chamber 13 through the fuel guiding pipe 12 are mixed in the primary combustion chamber 13 and burned, so that combustion is caused. The generated combustion exhaust gas is discharged toward the inside 1a of the furnace 1 through the first nozzle portion 16, and the amount of fuel to be guided to the fuel guiding pipe 12 is increased more than the first combustion state by the fuel regulating valve 31. When the amount of fuel to be guided to the fuel guiding pipe 12 is increased more than the first combustion state, a part of the fuel is not burned in the combustion of the primary combustion chamber 13, but is the same as the combustion exhaust gas. The nozzle portion 16 is ejected to the inside 1a of the furnace 1.

Then, in the second temperature range, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are controlled to open and close. As shown in FIG. 3, the following heat storage chamber 20A performs the following combustion. In the state in which the exhaust gas discharge valve 51A is closed, and the combustion exhaust gas in the interior 1a of the furnace 1 is prevented from being discharged through the regenerator 20A, the secondary air regulating valve 42A is opened, and an appropriate amount is introduced from the combustion air supply device 40. The secondary combustion air is heated by the heat of the heat storage material 21A accumulated in the regenerator 20A, and the heated secondary combustion air passes through the secondary air guide pipe 22A from the aforementioned The nozzle portion 23A is ejected toward the combustion exhaust gas that has been ejected to the inside 1a of the furnace 1 through the first nozzle unit 16, and burns the unburned fuel contained in the combustion exhaust gas (second combustion state).

In the other heat storage chamber 20B, the heat storage operation is performed such that the exhaust air discharge valve 51B is opened while the secondary air conditioning valve 42B is closed to prevent the secondary combustion air from being supplied to the heat storage chamber 20B. The exhaust gas from the inside 1a of the furnace 1 is guided into the regenerator 20B by the exhaust device 50, and the heat of the combustion exhaust gas is accumulated in the heat storage material 21B in the regenerator 20B, and the exhaust gas is passed through the exhaust gas. The discharge pipe 24B is discharged.

Then, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are opened and closed, and the combustion exhaust gas of the inside 1a of the furnace 1 is prevented from being discharged through the other heat storage chamber 20B, and the other is stored. The heat chamber 20B is a combustion operation in which an appropriate amount of secondary combustion air is introduced from the combustion air supply device 40 through the secondary air regulating valve 42B, and the heat of the heat storage material 21B accumulated in the heat storage chamber 20B is generated. The secondary combustion air is heated, and the heated secondary combustion air passes through the secondary air guide pipe 22B, and is discharged from the second nozzle portion 23B toward the inside of the furnace 1 through the first nozzle portion 16 The combustion exhaust gas is ejected to burn the unburned fuel contained in the combustion exhaust gas (second combustion state).

In the heat storage chamber 20A, the heat storage operation is performed by opening the exhaust gas discharge valve 51A while the secondary air conditioning valve 42A is closed to prevent the secondary combustion air from being supplied to the heat storage chamber 20A. The exhaust gas from the inside 1a of the furnace 1 is guided into the regenerator 20A by the exhaust device 50, and the heat of the combustion exhaust gas is accumulated in the heat storage material 21A of the regenerator 20A, and the combustion exhaust gas is passed through the exhaust gas discharge pipe. 24A and discharged.

Then, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are alternately opened and closed, and the combustion operation and the heat storage operation are performed alternately in the respective heat storage chambers 20A and 20B.

Here, when the combustion in the second combustion state as described above is performed, the unburned fuel contained in the combustion exhaust gas is surely burned, and the amount of combustion is increased, and the combustion of the inside 1a of the furnace 1 can be efficiently accumulated. The heat of the exhaust gas, Improve the overall thermal efficiency.

Next, when the temperature of the inside 1a of the furnace 1 is higher than the third temperature region in which the combustion in the second combustion state is higher than the second temperature region, for example, when the temperature at which the fuel naturally ignites is formed, as shown in FIG. 4 As shown, the primary air regulating valve 41 is closed to prevent the primary combustion air from being supplied to the primary air guiding pipe 11 from the combustion air supply device 40, and the fuel guided to the primary combustion chamber 13 through the fuel guiding pipe 12 is directly The first nozzle unit 16 is discharged toward the inside 1a of the furnace 1, and the secondary air regulating valves 42A and 42B are adjusted to supply the secondary combustion from the combustion air supply device 40 to the respective regenerators 20A and 20B. The amount of air used is increased, and the opening and closing of each of the secondary air regulating valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are controlled as described above.

Next, as shown in FIG. 4, in one of the regenerators 20A, the combustion operation is performed in a state in which the exhaust gas discharge valve 51A is closed to prevent the combustion exhaust gas inside the furnace 1a from being discharged through the regenerator 20A. The secondary air conditioning valve 42A is opened, and the increased secondary combustion air is introduced from the combustion air supply device 40, and the secondary combustion air is heated by the heat of the heat storage material 21A accumulated in the regenerator 20A. The heated secondary combustion air passes through the secondary air guide pipe 22A, and is discharged from the second nozzle portion 23A toward the fuel discharged to the inside 1a of the furnace 1 through the first nozzle portion 16 to be heated. The secondary combustion air is mixed with the fuel in the interior 1a of the furnace 1 and burned (third combustion state).

In the other heat storage chamber 20B, the heat storage operation is performed such that the exhaust air discharge valve 51B is opened while the secondary air conditioning valve 42B is closed to prevent the secondary combustion air from being supplied to the heat storage chamber 20B. The exhaust gas from the inside 1a of the furnace 1 is guided into the regenerator 20B by the exhaust device 50, and the heat of the combustion exhaust gas is accumulated in the heat storage material 21B in the regenerator 20B, and the exhaust gas is passed through the exhaust gas. The discharge pipe 24B is discharged.

Then, in the same manner as described above, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are alternately opened and closed, and the combustion operation and the heat storage operation are alternately performed in the respective heat storage chambers 20A and 20B.

Here, when the combustion in the third combustion state as described above is performed, the fuel discharged to the inside 1a of the furnace 1 as described above and the secondary combustion air heated as described above are heated to be naturally ignited. The inside 1a of the furnace 1 above the temperature is appropriately mixed and burned in a wide range, so that the combustion efficiency is improved, and the local temperature rise due to local combustion can be suppressed, and the generation of NOx can be appropriately prevented.

As a result, in the combustion apparatus A1 of the first embodiment, the combustion state can be appropriately controlled in accordance with the temperature of the inside 1a of the furnace 1, the stable combustion performance can be obtained from the low temperature region to the high temperature region, and the high temperature region can be appropriately suppressed. The generation of NOx in the domain.

(Embodiment 2)

In the combustion apparatus A2 of the second embodiment, as shown in Fig. 5, the fuel supply device 30 of the combustion apparatus A1 of the first embodiment shown in Fig. 1 is supplied with fuel to the fuel guide pipe via the fuel adjustment valve 31. Before 12, a preliminary air supply path (prepared air supply means) 43 for supplying pre-combustion air is supplied from the combustion air supply device 40, and a supply for pre-combustion air supply is provided in the preliminary air supply path 43. The air conditioning valve (prepared air control means) 44 is provided, and the spark plug 15 is provided in the fuel guiding pipe 12, and the rest is configured in the same manner as the combustion apparatus A1 of the first embodiment shown in Fig. 1. Further, the opening and closing of the valves 31, 41, 42, 44, and 51 in the sixth to ninth drawings is the same as in the first embodiment, and the open state is indicated by the reversed white, and the closed state is indicated by the black.

Here, in the combustion apparatus A2 of the second embodiment, before the combustion in the first combustion state is performed in the first temperature region where the temperature of the inside 1a of the furnace 1 is low, as shown in Fig. 6, the primary air is turned off. The valve 41 is adjusted to avoid a state in which the primary combustion air is supplied from the combustion air supply device 40 to the primary air guide pipe 11, and the fuel adjustment valve 31 guides a small amount of fuel from the fuel supply device 30 to the fuel guide pipe 12 And opening the aforementioned preliminary air conditioning valve 44, and supplying a small amount of preliminary combustion air from the combustion air supply device 40 through the preliminary air supply path 43 The fuel is guided to the fuel guiding pipe 12, and the fuel is premixed (premixed) with the pre-combustion air in the fuel guiding pipe 12.

Next, the premixed fuel and the preliminary combustion air are discharged from the fuel guiding pipe 12 to the primary combustion chamber 13 in this manner, and are ignited by the aforementioned spark plug 15 provided inside the fuel guiding pipe 12 to prepare The mixed fuel and the pre-combustion air are preliminarily burned, and the combustion exhaust gas generated by the preliminary combustion is discharged from the primary combustion chamber 13 toward the inside 1a of the furnace 1 through the first nozzle portion 16. As described above, the primary combustion chamber 13 and the inside 1a of the furnace 1 are preheated by the preliminary combustion (referred to as a preliminary heating combustion state). Further, in the first heating mode, the preliminary heating combustion state can be realized by forming a small amount of the primary combustion air and fuel in Fig. 2 .

Thereafter, in the first temperature region where the temperature of the inside 1a of the furnace 1 is low, as shown in Fig. 7, the primary air regulating valve 41 is opened to guide an appropriate amount of primary combustion air to the primary air guiding pipe 11, and The amount of fuel guided to the fuel guiding pipe 12 by the fuel adjusting valve 31 is increased more than that at the time of preliminary combustion, and is guided to the primary combustion by the primary air guiding pipe 11 as in the case of the combustion apparatus A1 of the first embodiment. The primary combustion air in the chamber 13 and the fuel guided to the primary combustion chamber 13 through the fuel guiding pipe 12 are mixed and burned in the primary combustion chamber 13, and the combustion exhaust gas generated by the combustion passes through the first nozzle portion 16, The first combustion chamber 13 is ejected toward the inside 1a of the furnace 1 (the first combustion state) And the aforementioned preliminary air regulating valve 44 is closed to prevent the preliminary combustion air from being supplied to the fuel guided to the fuel guiding pipe 12.

Further, in the second temperature region in which the temperature of the inside 1a of the furnace 1 is higher than the first temperature region due to the combustion in the first combustion state, the same as in the case of the combustion apparatus A1 of the first embodiment, The amount of fuel guided to the fuel guiding pipe 12 is increased more than in the case of the first combustion state, and the secondary air regulating valves 42A and 42B and the exhaust gas discharge valve are controlled in the same manner as in the case of the combustion apparatus A1 of the first embodiment. Opening and closing of 51A and 51B.

Then, as shown in Fig. 8, in one of the regenerators 20A, a combustion operation is performed in which the exhaust gas discharge valve 51A is closed to prevent the combustion exhaust gas inside the furnace 1a from being discharged through the regenerator 20A. The secondary air-conditioning valve 42A is opened, and an appropriate amount of secondary combustion air is introduced from the combustion air supply device 40, and the secondary combustion air is heated by the heat of the heat storage material 21A accumulated in the heat storage chamber 20A. The heated secondary combustion air passes through the secondary air guide pipe 22A, and is ejected from the second nozzle portion 23A toward the combustion exhaust gas that is ejected to the inside 1a of the furnace 1 through the first nozzle portion 16 to cause the combustion exhaust gas. The unburned fuel contained in the combustion is burned (second combustion state).

Further, in the other regenerator 20B, a heat storage operation is performed in which the secondary air regulating valve 42B is closed to prevent the secondary combustion air from being In the state of being supplied to the regenerator 20B, the exhaust gas discharge valve 51B is opened, and the combustion exhaust gas in the interior 1a of the furnace 1 is guided into the regenerator 20B by the exhaust device 50, so that the heat of the combustion exhaust gas is accumulated therein. After the heat storage material 21B in the regenerator 20B, the combustion exhaust gas is discharged through the exhaust gas discharge pipe 24B.

Then, in the same manner as described above, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are alternately opened and closed, and the combustion operation and the heat storage operation are alternately performed in the respective heat storage chambers 20A and 20B.

Further, in the third temperature region where the temperature of the inside 1a of the furnace 1 is higher than the second temperature region due to the combustion in the second combustion state, the fuel is naturally ignited, and the combustion apparatus A1 of the first embodiment In the same manner, as shown in Fig. 9, the primary air regulating valve 41 is closed to prevent the primary combustion air from being supplied from the combustion air supply device 40 to the primary air guiding pipe 11, so as to be guided to the primary fuel guiding pipe 12 through the fuel guiding pipe 12. The fuel of the primary combustion chamber 13 is directly discharged to the inside 1a of the furnace 1 through the first nozzle unit 16, and the secondary air regulating valves 42A and 42B are adjusted to be supplied from the combustion air supply device 40 to the respective regenerators. In the same manner as in the case of the combustion apparatus A1 of the first embodiment, the secondary air regulating valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are controlled to open and close in the same manner as in the case of the combustion apparatus A1 of the first embodiment.

Then, as shown in Fig. 9, in one of the regenerators 20A, the combustion operation is performed in a state in which the exhaust gas discharge valve 51A is closed to prevent the combustion exhaust gas inside the furnace 1a from being discharged through the regenerator 20A. The secondary air conditioning valve 42A is opened, and the increased secondary combustion air is introduced from the combustion air supply device 40, and the secondary combustion air is heated by the heat of the heat storage material 21A accumulated in the regenerator 20A. The heated secondary combustion air passes through the secondary air guide pipe 22A, and is discharged from the second nozzle portion 23A toward the fuel discharged to the inside 1a of the furnace 1 through the first nozzle portion 16 to be heated. The secondary combustion air is mixed with the fuel in the interior 1a of the furnace 1 and burned (third combustion state).

In the other regenerator 20B, the heat storage operation is performed such that the exhaust air discharge valve 51B is opened while the secondary air conditioning valve 42B is closed to prevent the secondary combustion air from being supplied to the regenerator 20B. The exhaust gas from the inside 1a of the furnace 1 is guided into the regenerator 20B by the exhaust device 50, and the heat of the combustion exhaust gas is accumulated in the heat storage material 21B in the regenerator 20B, and the exhaust gas is passed through the exhaust gas. The discharge pipe 24B is discharged.

Then, in the same manner as described above, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are alternately opened and closed, and the combustion operation and the heat storage operation are alternately performed in the respective heat storage chambers 20A and 20B.

In the same manner as the combustion apparatus A1 of the first embodiment, the combustion apparatus A2 of the second embodiment can appropriately control the combustion state in accordance with the temperature of the interior 1a of the furnace 1, and obtain stable combustion performance from the low temperature region to the high temperature region. Moreover, it is also possible to appropriately suppress the generation of NOx in a high temperature region.

(Embodiment 3)

In the combustion apparatus A3 of the third embodiment, as shown in Fig. 10, a fuel guiding tube is provided between the fuel guiding tube 12 and the primary air guiding tube 11 in the combustion apparatus A1 of the first embodiment shown in Fig. 1. a 12-long preliminary air guiding pipe (prepared air supply means) 17 in which a preliminary mixing portion 17a for mixing fuel and preliminary combustion air is formed, and the preliminary air guiding pipe 17 is provided from the foregoing The combustion air supply device 40 supplies a preliminary air supply path (prepared air supply means) 43 for pre-combustion air, and a preliminary air supply valve (prepared air control) for controlling the supply of the preliminary combustion air is provided in the preliminary air supply path 43. The means 44 is the same as the combustion apparatus A1 of the first embodiment shown in Fig. 1. Further, in the case of the first and second embodiments, the opening and closing of the valves 31, 41, 42, 44, and 51 in the drawings of Figs. 11 to 14 are shown in an open state in reverse white and in a closed state in black.

Next, in the combustion apparatus A3 of the third embodiment, before the combustion in the first burning state is performed in the first temperature region where the temperature of the inside 1a of the furnace 1 is low, as shown in Fig. 11, the primary air is turned off. Adjustment valve 41. In a state where the primary combustion air is supplied from the combustion air supply device 40 to the primary air guide pipe 11, the fuel adjustment valve 31 guides a small amount of fuel from the fuel supply device 30 to the fuel guide pipe 12, Further, the preliminary air conditioning valve 44 is opened, and a small amount of preliminary combustion air is supplied from the combustion air supply device 40 through the preliminary air supply path 43 to the preliminary air guiding pipe 17, so as to be guided through the preliminary air guiding pipe 17. The preliminary combustion air is mixed with the fuel guided in the fuel guiding pipe 12 in the preliminary mixing portion 17a.

Then, the fuel mixed in this manner and the pre-combustion air are discharged from the preliminary air guiding pipe 17 to the primary combustion chamber 13, and the spark plug 15 is ignited to prepare the premixed fuel and the preliminary combustion air for combustion. The combustion exhaust gas generated by the preliminary combustion is discharged from the primary combustion chamber 13 toward the inside 1a of the furnace 1 through the first nozzle portion 16. As described above, the primary combustion chamber 13 and the inside 1a of the furnace 1 are preheated by the preliminary combustion (preheated combustion state).

Thereafter, in the first temperature region where the temperature of the inside 1a of the furnace 1 is low, as shown in Fig. 12, the primary air regulating valve 41 is opened to guide an appropriate amount of primary combustion air to the primary air guiding pipe 11, and The amount of fuel guided to the fuel guiding pipe 12 by the fuel adjusting valve 31 is increased from the time of preliminary combustion, and is guided by the primary air guiding pipe 11 as in the case of the combustion apparatuses A1 and A2 of the first and second embodiments. Primary combustion air to primary combustion chamber 13 and through fuel guiding tube The fuel guided to the primary combustion chamber 13 is mixed and burned in the primary combustion chamber 13, and the combustion exhaust gas generated by the combustion passes through the first nozzle portion 16, and is ejected from the primary combustion chamber 13 toward the inside 1a of the furnace 1. (First combustion state), and the preliminary air conditioning valve 44 is closed to prevent the preliminary combustion air from being supplied to the preliminary air guiding pipe 17.

Further, in the second temperature region in which the temperature of the inside 1a of the furnace 1 is higher than the first temperature region due to the combustion in the first combustion state, the combustion devices A1 and A2 in the first and second embodiments are the same. Similarly, the amount of fuel to be guided to the fuel guiding pipe 12 is increased more than in the case of the first combustion state, and the opening and closing of the secondary air regulating valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are controlled.

Next, as shown in Fig. 13, the one regenerator 20A is operated in a state in which the exhaust gas discharge valve 51A is closed to prevent the combustion exhaust gas inside the furnace 1a from being discharged through the regenerator 20A. The secondary air conditioning valve 42A is opened, and an appropriate amount of secondary combustion air is introduced from the combustion air supply device 40, and the secondary combustion air is heated by the heat of the heat storage material 21A accumulated in the regenerator 20A. The heated secondary combustion air is ejected from the second nozzle portion 23A through the second nozzle portion 23A toward the combustion exhaust gas that is ejected to the inside 1a of the furnace 1 through the first nozzle portion 16, and the combustion exhaust gas is exhausted. The unburned fuel contained in the combustion is burned (second combustion state).

In the other regenerator 20B, the heat storage operation is performed such that the exhaust air discharge valve 51B is opened while the secondary air conditioning valve 42B is closed to prevent the secondary combustion air from being supplied to the regenerator 20B. The exhaust gas from the inside 1a of the furnace 1 is guided into the regenerator 20B by the exhaust device 50, and the heat of the combustion exhaust gas is accumulated in the heat storage material 21B in the regenerator 20B, and the exhaust gas is passed through the exhaust gas. The discharge pipe 24B is discharged.

Then, in the same manner as described above, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are alternately opened and closed, and the combustion operation and the heat storage operation are alternately performed in the respective heat storage chambers 20A and 20B.

Further, in the third temperature region where the temperature of the inside 1a of the furnace 1 is higher than the second temperature region due to the combustion in the second combustion state, the combustion in the first and second temperatures is the same as in the first and second embodiments. The devices A1 and A2 are the same. As shown in Fig. 14, the primary air regulating valve 41 is closed to prevent the primary combustion air from being supplied from the combustion air supply device 40 to the primary air guiding pipe 11 so as to be passed through the fuel guiding pipe 12. The fuel guided to the primary combustion chamber 13 is directly discharged to the inside 1a of the furnace 1 through the first nozzle portion 16, and the secondary air regulating valves 42A and 42B are adjusted to be supplied from the combustion air supply device 40 to The amount of secondary combustion air in each of the regenerators 20A and 20B is increased, and in the same manner as in the case of the combustion apparatus A1 of the first embodiment, each secondary space is controlled. The gas regulating valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are opened and closed.

Then, as shown in Fig. 14, the one regenerator 20A performs a combustion operation in which the exhaust gas discharge valve 51A is closed to prevent the combustion exhaust gas inside the furnace 1a from being discharged through the regenerator 20A. The secondary air-conditioning valve 42A is opened, and the increased secondary combustion air is guided from the combustion air supply device 40, and the secondary combustion air is heated by the heat of the heat storage material 21A accumulated in the heat storage chamber 20A. The heated secondary combustion air passes through the secondary air guide pipe 22A, and is discharged from the second nozzle portion 23A toward the fuel discharged to the inside 1a of the furnace 1 through the first nozzle portion 16 to heat the second The secondary combustion air is mixed with the fuel in the interior 1a of the furnace 1 and burned (third combustion state).

In the other regenerator 20B, the heat storage operation is performed such that the exhaust air discharge valve 51B is opened while the secondary air conditioning valve 42B is closed to prevent the secondary combustion air from being supplied to the regenerator 20B. The combustion exhaust gas in the interior 1a of the furnace 1 is guided into the regenerator 20B by the exhaust device 50, and the heat of the combustion exhaust gas is accumulated in the heat storage material 21B in the regenerator 20B, and the combustion exhaust gas is passed through the exhaust gas. The discharge pipe 24B is discharged.

Then, in the same manner as described above, the secondary air-conditioning valves 42A and 42B and the exhaust gas discharge valves 51A and 51B are alternately opened and closed, and the combustion operation and the heat storage are alternately performed in the respective heat storage chambers 20A and 20B. action.

As described above, in the combustion apparatus A3 of the third embodiment, similarly to the combustion apparatuses A1 and A2 of the first and second embodiments, the combustion state can be appropriately controlled in accordance with the temperature of the inside 1a of the furnace 1, from the low temperature region to the high temperature region. Stable combustion performance is obtained, and the generation of NOx in a high temperature region can be appropriately suppressed.

As described above, in the present invention, the four combustion states (the preliminary heating combustion state, the first combustion state, the second combustion state, and the third combustion state) can be realized by one combustion device, and are controlled by the state. These combustion states exert a superior effect that can be utilized in a wider temperature range than conventional combustion devices.

1‧‧‧ furnace

1a‧‧‧Internal

11‧‧‧One air guiding tube

12‧‧‧fuel guiding tube

13‧‧‧One combustion chamber

14‧‧‧ Stabilizer

15‧‧‧Mars plug

16‧‧‧1st nozzle section

20 (20A, 20B) ‧ ‧ regenerator

21 (21A, 21B) ‧ ‧ heat storage materials

22 (22A, 22B) ‧ ‧ secondary air guide tube

23(23A, 23B)‧‧‧2nd nozzle section

24 (24A, 24B) ‧ ‧ exhaust exhaust pipe

30‧‧‧fuel supply unit

31‧‧‧Fuel adjustment valve

40‧‧‧Combustion air supply unit

41‧‧‧One air adjustment valve (primary air control means)

42 (42A, 42B) ‧ ‧ secondary air regulating valve (secondary air control means)

50‧‧‧Exhaust device

51 (51A, 51B) ‧ ‧ exhaust exhaust valve

A1‧‧‧ burning device

Claims (7)

A combustion apparatus comprising: a primary air guiding tube for guiding primary combustion air; a fuel guiding tube provided on an inner peripheral side of the primary air guiding tube to guide fuel; and a primary combustion guided by the primary air guiding tube a primary combustion chamber that burns air by means of air and fuel guided by a fuel guiding tube; a first nozzle portion that communicates the primary combustion chamber with the inside of the furnace; and a secondary air that guides the secondary combustion air heated in the regenerator a guide pipe; and a second nozzle portion that discharges the secondary combustion air guided by the secondary air guide pipe to the inside of the furnace in the vicinity of the first nozzle portion; and the combustion device is provided to control a primary air control means for guiding the primary combustion air by the primary air guiding pipe; a fuel control means for controlling the guidance of the fuel by the fuel guiding pipe; and controlling the second air guiding pipe a secondary air control means for guiding the secondary combustion air; and contracting the first nozzle portion from the primary combustion chamber toward the inside of the furnace The combustion exhaust gas obtained by burning the primary combustion air and the fuel in the primary combustion chamber is ejected to the inside of the furnace at a high speed through the first nozzle portion. The combustion apparatus according to claim 1, wherein the preliminary air supply means for mixing the preliminary combustion air with the fuel before the fuel guided by the fuel guiding pipe is guided to the primary combustion chamber And providing preliminary air for controlling supply of preliminary combustion air by the preliminary air supply means Control means. The combustion apparatus according to claim 2, wherein the preliminary air supply means supplies the preliminary combustion air to the fuel guiding pipe, and prepares the fuel and the preliminary combustion air in the fuel guiding pipe. The combustion apparatus according to claim 2, wherein the preliminary air supply means is provided with a preliminary air guiding pipe between the fuel guiding pipe and the primary air guiding pipe, and guided by the preliminary air guiding pipe The pre-combustion air is premixed with the fuel guided by the fuel guiding tube before being guided to the primary combustion chamber. A combustion control method for a combustion apparatus, which is a combustion control method of a combustion apparatus of a combustion apparatus according to the first aspect of the patent application or the second aspect of the patent application, which is switched to the following three combustion states: inside the furnace In the first temperature region where the temperature is low, the primary combustion air guided by the primary air control means through the primary air guiding pipe and the fuel guided by the fuel guiding pipe by the fuel control means are once in the foregoing Combustion in the combustion chamber, the combustion exhaust gas is ejected to the first combustion state inside the furnace at a high speed through the first nozzle portion; and in the second temperature region in which the temperature inside the furnace becomes higher than the first temperature region, The amount of fuel guided by the fuel guiding tube is increased more than the first combustion state by the fuel control means, and the secondary air control means is passed through the second time The secondary combustion air guided by the air guiding pipe is discharged from the second nozzle portion to the inside of the furnace, and the primary combustion air guided by the primary air guiding pipe and the fuel guided by the fuel guiding pipe are in the primary combustion chamber. Combustion, the combustion exhaust gas is ejected to the inside of the furnace at a high speed through the first nozzle portion, and the second combustion air and the unburned fuel contained in the combustion exhaust gas are burned in the inside of the furnace. a combustion state; and in the third temperature region in which the temperature inside the furnace is higher than the second temperature region, the primary air control means stops the primary combustion air by the primary air control means And the amount of the secondary combustion air that is discharged from the second nozzle portion to the inside of the furnace by the secondary air guiding means is increased by the secondary air control means, and the fuel control means passes the fuel In a state where the amount of fuel guided by the guide pipe is increased, the fuel is discharged from the primary combustion chamber to the inside of the furnace through the first nozzle portion. The third combustion state in which the secondary combustion air and fuel are burned in the interior of the furnace. The combustion control method of a combustion apparatus according to claim 5, wherein the combustion apparatus according to the second aspect of the invention is used, wherein the fuel control means reduces fuel passing by the fuel control means before the first combustion state The amount of fuel guided by the pipe, and the preliminary combustion air supply means mixes the pre-combustion air with the fuel before being guided to the primary combustion chamber to prepare for combustion. The combustion control unit of the combustion device as described in claim 5 In the method, only the switching between the second combustion state and the third combustion state is performed.