Burner device and industrial furnace

Abstract

In a burner device (X) for mixing and burning air jetted from an air jetting port (21) and fuel (G) jetted from a fuel jetting nozzle (30), a short flame fuel jetting nozzle (31) for mixing and burning the fuel at a position close to the air jetted from the air jetting port, and a long flame fuel jetting nozzle (32) for mixing and burning the fuel at a position separated from the air jetted from the air jetting port are provided within the fuel jetting nozzle.

Description

Burner equipment and industrial furnaces

[0001] The present invention relates to a burner device that mixes and burns air ejected from an air outlet and fuel ejected from a fuel ejection nozzle, and an industrial furnace using such a burner device. In particular, the burner device allows for easy adjustment of the position where the air ejected from the air outlet and the fuel ejected from the fuel ejection nozzle are mixed and burned, and in an industrial furnace using such a burner device, the temperature distribution characteristics within the furnace can be easily adjusted by changing the position where the air ejected from the air outlet and the fuel ejected from the fuel ejection nozzle are mixed and burned, thereby enabling appropriate heating treatment of the material to be treated within the furnace.

[0002] BACKGROUND ART Conventionally, in industrial furnaces such as continuous heating furnaces, soaking furnaces, melting furnaces, and heat treatment furnaces, burner devices have generally been used that mix and burn air ejected from an air ejection port and fuel ejected from a fuel ejection nozzle.

[0003] Furthermore, in order to save energy, a regenerative burner device is used as this type of burner device, which recovers the heat from the combustion gas burned in the furnace while providing a heat storage section to heat the air used for combustion.

[0004] In an industrial furnace using a burner device such as the one described above, when heat treating a material to be treated, it may be necessary to heat the entire material to be treated evenly or to heat one side of the material to be treated more strongly, and in this case it is necessary to adjust the temperature distribution within the furnace.

[0005] In order to adjust the temperature distribution in the furnace in this way, Patent Document 1 proposes that primary fuel is ejected from the combustion air supply port of the regenerative burner, and secondary fuel is ejected from the secondary fuel nozzle into the furnace, thereby controlling the ratio of the supply amounts of primary fuel and secondary fuel.

[0006] However, the system disclosed in Patent Document 1 adjusts the temperature distribution in the furnace by controlling the ratio of the supply amounts of primary fuel and secondary fuel, so increasing the amount of primary fuel burned causes the problem of an increase in NOx emissions during combustion. In addition, because the secondary fuel is ejected parallel to the combustion air, the flame caused by secondary combustion becomes longer, making it very difficult to adjust the temperature distribution at various positions in the furnace while maintaining a constant overall amount of combustion in the furnace.

[0007] Furthermore, Patent Document 2 proposes providing a primary fuel nozzle within a combustion air nozzle so that it can be sprayed from around the flow of combustion air, providing multiple secondary fuel nozzles, and providing each of these secondary fuel nozzles with a flame stabilization mechanism at the nozzle at the tip of its piping, which includes a flow path that can supply flame stabilization air from around the secondary fuel being sprayed, so that it can be blown directly into the furnace from a location different from the combustion air and approximately parallel to the combustion air nozzle, and providing each with a secondary fuel flow rate control valve to change the flame temperature distribution.

[0008] However, even with the technique shown in Patent Document 2, if the combustion amount of the primary fuel ejected from the primary fuel nozzle is increased, there is a problem in that NOx emissions increase during combustion. Furthermore, because the secondary fuel is ejected from each secondary fuel nozzle parallel to the combustion air, the ratio between the amount of primary fuel ejected from the primary fuel nozzle and the amount of each secondary fuel ejected from each secondary fuel nozzle is controlled to adjust the temperature distribution within the furnace, which makes it very difficult to adjust the temperature distribution at various positions within the furnace while maintaining a constant overall combustion amount within the furnace.

[0009] Furthermore, Patent Document 3 proposes a method of operating a regenerative burner device in which each burner has one air nozzle for spraying air and multiple fuel injection nozzles for spraying fuel, and the multiple fuel injection nozzles have two or more injection directions, in which the position of the temperature peak, which is the high-temperature range of the combustion gas temperature, is changed by changing the injection amount of each of the multiple fuel injection nozzles.

[0010] However, in the system disclosed in Patent Document 3, multiple fuel injection nozzles with different injection directions are provided at different positions in the furnace, and therefore a fuel supply port corresponding to each fuel injection nozzle is required, which places restrictions on the position at which each fuel injection nozzle can be attached to the furnace. In addition, it is necessary to provide separate equipment such as piping for supplying fuel to each fuel injection nozzle, which increases the equipment cost and makes it difficult to control the fuel supplied to each fuel injection nozzle.

[0011] Furthermore, the scrap melting furnace of Patent Document 4 is provided with a main burner that sprays a flame (long flame) toward the piled-up scrap, and an auxiliary burner that sprays a short flame to melt the scrap piled up in front of the main burner, and the point at which the flame is aimed is changed between a distant and a near point as needed while monitoring the melting state so that the scrap melts uniformly.

[0012] However, in the device disclosed in Patent Document 4, in order to change the point at which the flame is applied to the piled scrap to heat it between a close and a far location, a plurality of dedicated burners are required, which results in problems such as increased parts costs, a complex structure, and the need for space around the device.

[0013] JP-A-9-145047 JP-A 2003-74834 Patent No. 6764000 JP-A 11-325734

[0014] The present invention aims to solve the above-mentioned problems in a burner device that mixes and burns air ejected from an air outlet and fuel ejected from a fuel ejection nozzle, and in an industrial furnace that uses such a burner device.

[0015] In particular, the object of the present invention is to make it possible to easily adjust the position in the burner device where the air ejected from the air outlet and the fuel ejected from the fuel ejection nozzle are mixed and burned, and to easily change the position in an industrial furnace using such a burner device where the air ejected from the air outlet and the fuel ejected from the fuel ejection nozzle are mixed and burned, thereby changing the length of the flame to change the heating point and adjusting the temperature distribution within the furnace, thereby enabling the material to be appropriately heated within the furnace.

[0016] In order to solve the above-mentioned problems, the burner device of the present invention is a burner device in which air ejected from an air outlet and fuel ejected from a fuel ejection nozzle are mixed and burned, and the fuel ejection nozzle is provided with a short-flame fuel ejection nozzle that mixes and burns fuel at a position close to the air ejected from the air outlet, and a long-flame fuel ejection nozzle that mixes and burns fuel at a position distant from the air ejected from the air outlet.

[0017] Furthermore, as in the burner apparatus of the present invention, by providing within one fuel injection nozzle a short-flame fuel injection nozzle that mixes and burns fuel close to the air injected from the air injection port, and a long-flame fuel injection nozzle that mixes and burns fuel away from the air injection port, it is no longer necessary to provide multiple fuel injection nozzles with different injection directions at different positions in the furnace, as shown in Patent Documents 3 and 4. As a result, it is no longer necessary to provide fuel supply ports corresponding to each fuel injection nozzle in the furnace, which eliminates restrictions on the installation position of each fuel injection nozzle in the furnace, the need to provide separate equipment such as piping to supply fuel to each fuel injection nozzle, which increases equipment costs, and the complexity of controlling the fuel supplied to each fuel nozzle injection.

[0018] Furthermore, in the burner apparatus of the present invention, at least one of the angle at which fuel is ejected from the short-flame nozzle portion at the tip of the short-flame fuel ejection nozzle toward the air ejected from the air ejection port and the angle at which fuel is ejected from the long-flame nozzle portion at the tip of the long-flame fuel ejection nozzle toward the air ejected from the air ejection port can be adjusted. This makes it possible to easily adjust the position at which fuel ejected from the short-flame fuel ejection nozzle is mixed with air ejected from the air ejection port and burned, or the position at which fuel ejected from the long-flame fuel ejection nozzle is mixed with air ejected from the air ejection port and burned. Note that, although not shown, methods for adjusting the angle may include mechanically moving the short-flame nozzle portion and the long-flame nozzle portion that eject fuel from the fuel nozzle from the outside to change the angle, or manually replacing the components of the short-flame nozzle portion and the long-flame nozzle portion with components that have a different ejection angle.

[0019] Furthermore, the burner device of the present invention may be provided with a switching means for switching the fuel injection nozzle for injecting fuel between the short flame fuel injection nozzle and the long flame fuel injection nozzle, thereby making it possible to clearly distinguish between the short flame and the long flame.

[0020] Furthermore, the burner apparatus of the present invention can be provided with a short-flame adjustment valve that adjusts the amount of fuel introduced to the short-flame fuel injection nozzle, and a long-flame adjustment valve that adjusts the amount of fuel introduced to the long-flame fuel injection nozzle. This makes it possible to easily adjust, while maintaining a constant amount of fuel to be mixed with air injected from the air injection port and burned, the amount of fuel injected from the short-flame fuel injection nozzle that is mixed with air injected from the air injection port and burned at a position close to the air injection port, and the amount of fuel injected from the long-flame fuel injection nozzle that is mixed with air injected from the air injection port and burned at a position distant from the air injection port.

[0021] In the burner apparatus of the present invention, fuel injection nozzles each having a short flame fuel injection nozzle and a long flame fuel injection nozzle can be provided symmetrically on both sides of the air injection port from which air is injected. In this way, when fuel injection nozzles each having a short flame fuel injection nozzle and a long flame fuel injection nozzle are provided symmetrically on both sides of the air injection port and fuel is injected from the short flame fuel injection nozzles or the long flame fuel injection nozzles on both sides, the fuel injected from the short flame fuel injection nozzles or the long flame fuel injection nozzles on both sides joins with the air injected from the air injection port at a position where they intersect and are burned, and the fuel can be burned along the direction of air injection whether the flame is close to the air injection port or far from the air injection port.

[0022] In this way, the flame is not tilted relative to the direction of air ejection as in Patent Document 3, so there is no temperature imbalance in the furnace, and the temperature distribution can be made symmetrical relative to the direction of air ejection.

[0023] In the burner device of the present invention, a heat storage section containing a heat storage material can be provided in the air guide tube that guides air to the air outlet. In this way, the air is heated by the heat storage material stored in the heat storage section, and the heated air is ejected from the air outlet and mixed with the fuel ejected from the short flame fuel ejection nozzle or the long flame fuel ejection nozzle, allowing for efficient combustion. On the other hand, when combustion is stopped, the combustion exhaust gas after combustion can be guided through the air outlet to the heat storage section provided in the air guide tube, and the heat of the combustion exhaust gas can be stored in the heat storage material accommodated in the heat storage section.

[0024] In this way, the combustion air can be preheated by the heat of the combustion exhaust gas after combustion via the heat storage section, thereby saving fuel.

[0025] In addition, in the industrial furnace of the present invention, a burner device such as the one described above is provided in an industrial furnace having a furnace wall on which air ejected from an air ejection port and fuel ejected from a fuel ejection nozzle are mixed and burned.

[0026] In the industrial furnace of the present invention, a plurality of the burner devices can be provided on both furnace walls.

[0027] Furthermore, in the industrial furnace of the present invention, a burner device is provided on the furnace wall, which mixes and burns air ejected from an air outlet and fuel ejected from a fuel ejection nozzle, and the burner device is a burner device in which a heat storage section containing a heat storage material is provided in an air guide tube that guides air to the air outlet, and the combustion exhaust gas after combustion in the furnace is guided through the air outlet to the heat storage section provided in the air guide tube, so that the heat of the combustion exhaust gas is stored in the heat storage material stored in the heat storage section, and the air heated by the heat stored in the heat storage material in the heat storage section is guided by the air guide tube to the air outlet and ejected into the furnace. In this way, air can be heated by the heat storage material stored in the heat storage section as described above, and the heated air can be ejected from the air outlet and mixed with the fuel ejected from the short flame fuel ejection nozzle and the long flame fuel ejection nozzle for efficient combustion.On the other hand, when combustion is stopped, the combustion exhaust gas after combustion can be guided through the air outlet to the heat storage section provided in the air guide pipe, and the heat of the combustion exhaust gas can be stored in the heat storage material contained in the heat storage section.

[0028] Here too, if the fuel injection nozzles equipped with the short flame fuel injection nozzle and the long flame fuel injection nozzle are arranged symmetrically on both sides of the air injection port that ejects air, the flame will not be oblique to the air injection direction as in Patent Document 3, so there will be no temperature imbalance in the furnace, and it will be possible to achieve a temperature distribution that is symmetrical with respect to the air injection direction.

[0029] Furthermore, in the industrial furnace of the present invention, when the burner device is a burner device having a heat storage section containing a heat storage material provided in an air guide pipe that guides air to the air outlet, a plurality of such burner devices can be provided on both furnace walls, and each burner device can alternately perform a heat storage operation in which the combustion exhaust gas after combustion in the furnace is guided through the air outlet provided in one furnace wall to the heat storage section provided in the air guide pipe to store the heat of the combustion exhaust gas in the heat storage material stored in the heat storage section, and a combustion operation in which air heated by the heat storage material stored in the heat storage section is ejected from the air outlet provided in the other furnace wall into the furnace and combusted. In this way, by installing two burner devices in a pair facing each other on both sides of the furnace wall, the heat storage operation and the combustion operation can be performed alternately, and an industrial furnace equipped with the burner device can obtain an optimal temperature distribution, enable continuous operation with reduced fuel consumption, and save energy.

[0030] As in the burner device of the present invention, by providing within one fuel injection nozzle a short-flame fuel injection nozzle that mixes and burns fuel at a position close to the air injected from the air injection port, and a long-flame fuel injection nozzle that mixes and burns fuel at a position distant from the air injected from the air injection port, the position where the air injected from the air injection port and the fuel injected from the fuel injection nozzle are mixed and burned can be easily adjusted with simple equipment, and the operating conditions can be changed during operation without stopping the equipment.

[0031] Furthermore, in the industrial furnace of the present invention, since the burner device as described above is used, by changing the position where the air ejected from the air outlet and the fuel ejected from the fuel ejection nozzle are mixed and burned, it is possible to easily adjust the length of the flame to change the point at which the heated object is heated, or to adjust the temperature distribution within the furnace.

[0032] Furthermore, because these can be achieved with a single fuel injection nozzle, the structure is not complicated and space around the device can be secured.

[0033] 1 is a schematic explanatory diagram showing a state in which a fuel injection nozzle provided with a short flame fuel injection nozzle and a long flame fuel injection nozzle is provided on one side of an air injection port in a burner device and an industrial furnace according to a first embodiment of the present invention, in which fuel is injected into the furnace from the long flame fuel injection nozzle provided in the fuel injection nozzle and mixed with air injected from the air injection port at a position away from the furnace wall to combust the fuel. 1 is a schematic diagram showing a modified example of the burner apparatus and industrial furnace according to the first embodiment, in which a short-flame adjusting valve is provided in the short-flame fuel supply pipe to adjust the amount of fuel supplied to the short-flame fuel injection nozzle, and a long-flame adjusting valve is provided in the long-flame fuel supply pipe to adjust the amount of fuel supplied to the long-flame fuel injection nozzle, and the amount of fuel injected from the short-flame fuel injection nozzle and the long-flame fuel injection nozzle are adjusted to combust by adjusting the amount of fuel injected from the short-flame fuel injection nozzle. 2 is a schematic diagram showing a modified example of the burner apparatus and industrial furnace according to the first embodiment, in which a short-flame adjusting valve is provided in the short-flame fuel supply pipe to adjust the amount of fuel supplied to the long-flame fuel injection nozzle, and the amount of fuel injected from the long-flame fuel injection nozzle are adjusted to combust by adjusting the amount of fuel injected from the short-flame fuel injection nozzle and the long-flame fuel injection nozzle. 3 is a schematic diagram showing a modified example of the burner apparatus and industrial furnace according to the first embodiment, in which a short-flame adjusting valve is provided in the short-flame fuel supply pipe to adjust the amount of fuel supplied to the long-flame fuel injection nozzle, and the amount of fuel injected from the long-flame fuel injection nozzle are adjusted to combust by adjusting the amount of fuel injected from the short-flame fuel injection nozzle. FIG. 10 is a schematic explanatory diagram showing a state in which fuel is injected into the furnace from long-flame fuel injection nozzles provided in each fuel injection nozzle on both sides of the air injection port in the burner device and industrial furnace of the above-mentioned embodiment 2, and the fuel is mixed with air injected from the air injection port at a position far from the furnace wall to combust.1A is a schematic diagram showing a state in which, in the burner device and industrial furnace of the second embodiment, fuel is injected into the furnace from a short-flame fuel injection nozzle provided in a fuel injection nozzle on one side of an air injection port and from a long-flame fuel injection nozzle provided in a fuel injection nozzle on the opposite side of the air injection port, and the fuel is mixed with the air injected from the air injection port both close to the furnace wall and far from the furnace wall to combust, and FIG. 1B is a schematic diagram showing a state in which fuel is injected into the furnace from a short-flame fuel injection nozzle and a long-flame fuel injection nozzle provided in a fuel injection nozzle on both sides of the air injection port, and the fuel is mixed with the air injected from the air injection port both close to the furnace wall and far from the furnace wall to combust, and the amount of fuel injected from the short-flame fuel injection nozzle and the amount of fuel injected from the long-flame fuel injection nozzle are adjusted to combust. FIG. 3 is a schematic explanatory diagram showing a burner device and industrial furnace according to a third embodiment of the present invention, in which fuel injection nozzles each having a short flame fuel injection nozzle and a long flame fuel injection nozzle are provided symmetrically on both sides of an air injection port, and a heat storage section containing a heat storage material is provided in an air guide tube that guides air to the air injection port, and the burner device is provided so as to face both furnace walls. In the burner device and industrial furnace of the third embodiment, (A) is a schematic explanatory diagram showing a state in which, in a pair of opposing burner devices provided on both furnace walls, the combustion exhaust gas after combustion in the furnace is guided through the air outlet to the heat storage section provided in the air guide pipe, and the heat of the combustion exhaust gas is stored in the heat storage material contained in the heat storage section, and a combustion operation is alternately performed in which the air heated by the heat storage material stored in the heat storage section is ejected from the air outlet into the furnace to combust fuel, and during the combustion operation, fuel is ejected from long flame fuel ejection nozzles provided in each fuel ejection nozzle on both sides of the air ejection outlet and mixed with the heated air ejected from the air ejection outlet at a position away from the furnace wall to combust the fuel; and (B) is a schematic diagram showing the temperature distribution in the furnace.In the burner device and industrial furnace of the third embodiment, (A) is a schematic explanatory diagram showing a state in which, in a pair of opposing burner devices provided on both furnace walls, the combustion exhaust gas after combustion in the furnace is guided through the air outlet to the heat storage section provided in the air guide pipe, and the heat of the combustion exhaust gas is stored in the heat storage material contained in the heat storage section, and a combustion operation is alternately performed in which the air heated by the heat storage material stored in the heat storage section is ejected from the air outlet into the furnace to combust fuel, and during the combustion operation, fuel is ejected from short-flame fuel ejection nozzles provided in each fuel ejection nozzle on both sides of the air ejection outlet into the furnace and mixed with the heated air ejected from the air ejection outlet at a position close to the furnace wall to combust the fuel; and (B) is a schematic diagram showing the temperature distribution in the furnace. In the burner device and industrial furnace of the third embodiment, (A) is a pair of opposing burner devices provided on both furnace walls, in which a heat storage operation is performed in which the combustion exhaust gas after combustion in the furnace is led through the air outlet to the heat storage section provided in the air guide pipe, and the heat of the combustion exhaust gas is stored in the heat storage material accommodated in the heat storage section, and a combustion operation is performed in which the air heated by the heat stored in the heat storage section is ejected from the air outlet into the furnace to combust fuel, during the combustion operation, FIG. 1 is a schematic diagram showing a state in which fuel is injected into the furnace from long-flame fuel injection nozzles provided in each fuel injection nozzle on both sides of the air injection port, and the fuel is mixed with heated air injected from the air injection port at a position away from the furnace wall to combust, while in a burner device provided in the opposite furnace wall, fuel is injected into the furnace from short-flame fuel injection nozzles provided in each fuel injection nozzle on both sides of the air injection port, and the fuel is mixed with heated air injected from the air injection port at a position close to the furnace wall to combust, (A) is a schematic diagram showing the temperature distribution in the furnace.In the burner device and industrial furnace of the third embodiment, (A) is a schematic explanatory diagram showing a state in which, in a pair of opposing burner devices provided on both furnace walls, combustion exhaust gas after combustion in the furnace is guided through the air outlet to the heat storage section provided in the air guide pipe, and the heat of the combustion exhaust gas is stored in the heat storage material accommodated in the heat storage section, and a heat storage operation in which air heated by the heat stored in the heat storage section is ejected from the air outlet into the furnace to combust fuel, alternately performed; during the combustion operation, fuel is ejected into the furnace from a long-flame fuel ejection nozzle provided in a fuel ejection nozzle on one side of the air ejection port, and fuel is ejected into the furnace from a short-flame fuel ejection nozzle provided in a fuel ejection nozzle on one side of the air ejection port, and the fuel is mixed with the heated air ejected from the air ejection port at a position away from the furnace wall and a position close to the furnace wall, and the fuel is combusted; and (B) is a schematic diagram showing the temperature distribution in the furnace. In the burner device and industrial furnace of the third embodiment, a pair of opposing burner devices are provided on both furnace walls, and the combustion exhaust gas after combustion in the furnace is guided through the air outlet to the heat storage section provided in the air guide pipe to store the heat of the combustion exhaust gas in the heat storage material contained in the heat storage section, and the air heated by the heat stored in the heat storage section is ejected from the air outlet into the furnace to combust the fuel. This is a schematic explanatory diagram showing a state in which a plurality of consecutive burner devices provided on one furnace wall perform the combustion operation, while a plurality of consecutive burner devices provided on the opposite furnace wall perform the heat storage operation.

[0034] The burner device and industrial furnace according to the embodiments of the present invention will be specifically described below with reference to the accompanying drawings. Note that the burner device and industrial furnace according to the present invention are not limited to the embodiments shown below, and can be appropriately modified and implemented within the scope of the invention.

[0035] (Embodiment 1) In a burner device X for an industrial furnace according to embodiment 1, as shown in Figures 1 and 2, an air outlet 21 is provided in a furnace wall 11 of the furnace 10, through which air guided by an air guide pipe 20 is ejected into the furnace 10, and a fuel ejection nozzle 30 is provided in the vicinity of the air outlet 21, inclined in a direction toward the air ejected from the air outlet 21, through which fuel G is ejected onto the furnace wall 11.

[0036] Within the fuel injection nozzle 30, a short flame fuel injection nozzle 31 is provided at a position on the air outlet 21 side, and a long flame fuel injection nozzle 32 is provided next to the short flame fuel injection nozzle 31 at a position farther from the air outlet 21 than the short flame fuel injection nozzle 31. A short flame nozzle section 31a is provided at the tip of the short flame fuel injection nozzle 31, which injects fuel G toward a position close to the air injected from the air outlet 21, and a long flame nozzle section 32a is provided at the tip of the long flame fuel injection nozzle 32, which injects fuel G toward a position farther from the air injected from the air outlet 21.

[0037] In this embodiment, the short flame nozzle portion 31a and the long flame nozzle portion 32a are protruded from the tip end of the short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32, and the respective injection angles are tilted toward the farther and closer sides, respectively, to clearly distinguish between the short flame and the long flame. However, although not shown, it is also possible to provide angled holes instead of providing the protruding short flame nozzle portion 31a and the long flame nozzle portion 32a. Also, although not shown, if it is desired to reduce the difference between the short flame and the long flame, it is not necessary to tilt the short flame nozzle portion 31a and the long flame nozzle portion 32a.

[0038] In addition, in the fuel injection nozzle 30, when switching between the short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32 that inject fuel G using a switching means, a short flame on-off valve 33b is provided on the short flame fuel supply pipe 33a that supplies fuel G to the short flame fuel injection nozzle 31, and a long flame on-off valve 34b is provided on the long flame fuel supply pipe 34a that guides fuel G to the long flame fuel injection nozzle 32, and a control device 36 controls the opening and closing of the short flame on-off valve 33b and the long flame on-off valve 34b.

[0039] 1, in the burner apparatus X according to the first embodiment, when the control device 36 closes the short flame on-off valve 33b while opening the long flame on-off valve 34b, fuel G is supplied only to the long flame fuel injection nozzle 32 through the long flame fuel supply pipe 34a, and the fuel G is injected from the long flame nozzle portion 32a at the tip of the long flame fuel injection nozzle 32 to a position away from the air injected from the air injection port 21, where it is mixed with the air and combusted, so that the temperature inside the furnace 10 at the position away from the air injection port 21 becomes higher than the temperature in the vicinity of the air injection port 21. In the drawing, the short flame on-off valve 33b and the long flame on-off valve 34b are shown in black when closed and in white when open.

[0040] On the other hand, as shown in FIG. 2, when the control device 36 closes the long flame on-off valve 34b and opens the short flame on-off valve 33b, fuel G is supplied only to the short flame fuel injection nozzle 31 through the short flame fuel supply pipe 33a, and the fuel G is injected from the short flame nozzle portion 31a at the tip of the short flame fuel injection nozzle 31 to a position close to the air injected from the air injection port 21, where it is mixed with the air and combusted, and the temperature inside the furnace 10 near the air injection port 21 becomes higher than the temperature at a position away from the air injection port 21.

[0041] As a result, the control device 36 controls the opening and closing of the short flame on-off valve 33b and the long flame on-off valve 34b, making it possible to easily control the temperature inside the furnace 10 at a position away from the air outlet 21 and the temperature inside the furnace 10 at a position close to the air outlet 21.

[0042] In addition, in the modified burner device X shown in Figure 3, in addition to the short flame on / off valve 33b, a short flame fuel supply pipe 33a that supplies fuel G to the short flame fuel injection nozzle 31 is provided with a short flame adjustment valve 33c that adjusts the amount of fuel G that is led to the short flame fuel injection nozzle 31, and in addition to the long flame on / off valve 34b, a long flame fuel supply pipe 34a that supplies fuel G to the long flame fuel injection nozzle 32 is provided with a long flame adjustment valve 34c that adjusts the amount of fuel G that is led to the long flame fuel injection nozzle 32, and the control device 36 controls the short flame on / off valve 33b and the long flame on / off valve 34b, as well as the short flame adjustment valve 33c and the long flame adjustment valve 34c.

[0043] In the burner device X of this modified example, as shown in FIG. 3, the control device 36 opens the short flame on-off valve 33b and the long flame on-off valve 34b, and controls the short flame adjustment valve 33c and the long flame adjustment valve 34c to adjust the amount of fuel G led to the short flame fuel injection nozzle 31 through the short flame adjustment valve 33c and the amount of fuel G led to the long flame fuel injection nozzle 32 through the long flame adjustment valve 34c, thereby adjusting the amount of fuel G to be injected from the short flame nozzle portion 31a to a position close to the air injected from the air outlet 21 and to be burned, and the amount of fuel G to be injected from the long flame nozzle portion 32a to a position away from the air injected from the air outlet 21 and to be burned.

[0044] In this way, while keeping the amount of fuel G to be mixed with the air ejected from the air outlet 21 and burned constant, the amount of fuel G to be mixed with the air ejected from the air outlet 21 at a position close to the air outlet 21 and burned and the amount of fuel G to be mixed with the air ejected from the air outlet 21 at a position distant from the air outlet 21 and burned can be easily adjusted, making it possible to easily control the temperature at each position within the furnace 10, reducing the temperature change between positions close to and distant from the air outlet 21, or making it possible to change the temperature as desired.

[0045] In addition, it is easy to change the heating point of the object by adjusting the length of the flame and adjust the temperature distribution inside the furnace. Taking advantage of this, it can be used as a burner for a melting furnace.

[0046] (Embodiment 2) In a burner device X for an industrial furnace according to embodiment 2, as shown in FIGS. 4 to 6, air outlets 21 for ejecting air introduced by air guide pipes 20 into the furnace 10 are provided on the furnace wall 11 of the furnace 10, and fuel ejection nozzles 30 for ejecting fuel G are provided symmetrically on both sides of the furnace wall 11 near the air outlets 21, each inclined in a direction toward the air ejected from the air outlets 21.

[0047] In each fuel injection nozzle 30, similar to the fuel injection nozzle 30 of embodiment 1, a short flame fuel injection nozzle 31 is provided at a position on the air outlet 21 side within the fuel injection nozzle 30, and long flame fuel injection nozzles 32 are provided side by side at a position farther from the air outlet 21 than the short flame fuel injection nozzle 31, and a short flame nozzle section 31a is provided at the tip of the short flame fuel injection nozzle 31, which sprays fuel G toward a position close to the air air ejected from the air outlet 21, and a long flame nozzle section 32a is provided at the tip of the long flame fuel injection nozzle 32, which sprays fuel G toward a position farther from the air air ejected from the air outlet 21.

[0048] When switching between the short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32 that inject fuel G in each fuel injection nozzle 30 using a switching means, a short flame on-off valve 33b is provided in the short flame fuel supply pipe 33a that supplies fuel G to each short flame fuel injection nozzle 31, and a long flame on-off valve 34b is provided in the long flame fuel supply pipe 34a that supplies fuel G to each long flame fuel injection nozzle 32, and a control device 36 controls the opening and closing of each of the short flame on-off valves 33b and each long flame on-off valve 34b.

[0049] In the burner apparatus X according to the second embodiment, as shown in FIG. 4 , when the control device 36 closes the long flame on-off valves 34 b and opens the short flame on-off valves 33 b in each fuel injection nozzle 30 on both sides of the air outlet 21, the fuel G is not led to the long flame fuel supply pipes 34 a on both sides but is supplied to the short flame fuel injection nozzles 31 on both sides through the short flame fuel supply pipes 33 a on both sides, and the fuel G is injected from the short flame nozzle portions 31 a at the tips of the short flame fuel injection nozzles 31 on both sides toward a position close to the air injected from the air outlet 21, where it joins with and combusts at a position close to where it intersects with the air injected from the air outlet 21, and a flame caused by the combustion of the fuel G is formed along the injection direction of the air at a position close to the air outlet 21.

[0050] In this way, the flame is not tilted relative to the direction of air ejection as in Patent Document 3, so there is no temperature imbalance in the furnace, and the temperature distribution can be made symmetrical relative to the direction of air ejection.

[0051] Furthermore, in the burner apparatus X according to the second embodiment, as shown in FIG. 5 , when the control device 36 closes the short flame on-off valves 33 b and opens the long flame on-off valves 34 b in each fuel injection nozzle 30 on both sides of the air outlet 21, the fuel G is not led to the short flame fuel supply pipes 33 a on both sides but is supplied to the long flame fuel injection nozzles 32 on both sides through the long flame fuel supply pipes 34 a on both sides, and the fuel G is injected from the long flame nozzle portions 32 a at the tips of the long flame fuel injection nozzles 32 on both sides toward a position distant from the air injected from the air outlet 21, and is combined with the air injected from the air outlet 21 at a position distant from where the two flows intersect and are burned, and a flame due to the combustion of the fuel G is formed along the injection direction of the air at a position distant from the air outlet 21.

[0052] In this way, as in the above case, the flame is not tilted relative to the direction of air ejection, so that there is no temperature imbalance in the furnace, and the temperature distribution can be made symmetrical relative to the direction of air ejection.

[0053] In the burner device X according to the second embodiment, as shown in FIG. 6A, the control device 36 closes the long flame on-off valve 34b and opens the short flame on-off valve 33b in the fuel injection nozzle 30 on one side of the air injection port 21, while closing the short flame on-off valve 33b and opening the long flame on-off valve 34b in the fuel injection nozzle 30 on the opposite side of the air injection port 21. In this case, the fuel G is not guided to the long flame fuel supply pipe 34a in the fuel injection nozzle 30 on the side where the long flame on-off valve 34b is closed, but is guided to the short flame fuel injection port through the short flame fuel supply pipe 33a. The fuel G is supplied to the fuel injection nozzle 31, and is sprayed from the short flame nozzle portion 31a at the tip of the short flame fuel injection nozzle 31 toward a position close to the air injected from the air outlet 21. On the other hand, in the fuel injection nozzle 30 on the opposite side where the short flame on-off valve 33b is closed, the fuel G is not guided to the short flame fuel supply pipe 33a, but is supplied to the long flame fuel injection nozzle 32 through the long flame fuel supply pipe 34a, and the fuel G is sprayed from the long flame nozzle portion 32a at the tip of the long flame fuel injection nozzle 32 toward a position away from the air injected from the air outlet 21.

[0054] As a result, in the fuel injection nozzle 30 on one side with the short flame on-off valve 33b open and the long flame on-off valve 34b closed as described above, the fuel G injected from the short flame nozzle portion 31a is mixed and burned at a position close to the air injected from the air outlet 21, and in the fuel injection nozzle 30 on the other side with the short flame on-off valve 33b closed and the long flame on-off valve 34b open, the fuel G injected from the long flame nozzle portion 32a is mixed and burned at a position distant from the air outlet 21. This makes it possible to burn the fuel G at positions close to and distant from the air outlet 21, and the temperature at each position within the furnace 10 can be easily controlled, and the temperature change between positions close to and distant from the air outlet 21 can be minimized, or the temperature can be changed as desired.

[0055] Furthermore, it becomes easy to change the point at which the object is heated by adjusting the length of the flame, and to adjust the temperature distribution within the furnace.

[0056] Furthermore, as shown in Figure 6 (B), even if both the short flame on-off valve 33b and the long flame on-off valve 34b are opened in the fuel injection nozzles 30 on both sides, the fuel G can be burned at positions close to and away from the air outlet 21. As in the above case, the temperature at each position in the furnace 10 can be easily controlled, and the temperature difference between the positions close to and away from the air outlet 21 can be reduced.

[0057] Furthermore, the contents shown in Figures 4 to 6(B) above do not have to be decided upon as a single item during operation of the furnace 10, but rather multiple items may be combined and operation may be carried out while changing the order and time depending on the situation.

[0058] (Embodiment 3) In a burner device X for an industrial furnace according to embodiment 3, as shown in FIG. 7 , fuel injection nozzles 30 for spraying fuel G are provided symmetrically on both sides of the furnace wall 11 near the air outlets 21, similar to that of embodiment 2, at an angle toward the air being ejected from the air outlets 21. Within each fuel injection nozzle 30, a short-flame fuel injection nozzle 31 is provided at a position closer to the air outlet 21, and long-flame fuel injection nozzles 32 are provided side by side at positions farther from the air outlet 21 than the short-flame fuel injection nozzle 31. The tip of the short-flame fuel injection nozzle 31 is provided with a short-flame nozzle section 31 a for spraying fuel G toward a position close to the air being ejected from the air outlet 21, and the tip of the long-flame fuel injection nozzle 32 is provided with a long-flame nozzle section 32 a for spraying fuel G toward a position away from the air being ejected from the air outlet 21.

[0059] Furthermore, when switching between the short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32 that inject fuel G in each of the fuel injection nozzles 30 using a switching means, similar to the first and second embodiments, a short flame on-off valve 33b is provided in the short flame fuel supply pipe 33a that supplies fuel G to each of the short flame fuel injection nozzles 31, and a long flame on-off valve 34b is provided in the long flame fuel supply pipe 34a that supplies fuel G to each of the long flame fuel injection nozzles 32, and a control device 36 controls the opening and closing of each of the short flame on-off valves 33b and each of the long flame on-off valves 34b.

[0060] In the burner device X for an industrial furnace according to the third embodiment, a heat storage section 40 containing a heat storage material (not shown) is provided in each air guide pipe 20 that guides air to the air outlets 21, an air on-off valve 41a is provided in an air supply pipe 41 that supplies air to the heat storage section 40, and an exhaust gas on-off valve 42a is provided in an exhaust gas pipe 42 that stores heat in the heat storage material in the heat storage section 40 and discharges the combustion exhaust gas Ga after the combustion of fuel G, and the opening and closing of the air on-off valve 41a and the exhaust gas on-off valve 42a is controlled by the control device 36. Therefore, the burner device can also be used for such a heat storage alternating combustion burner (regenerative burner).

[0061] In the industrial furnace according to the third embodiment, as shown in FIGS. 8 to 12, the burner devices X are arranged in pairs so as to face the furnace walls 11 on both sides in the furnace width direction of the furnace 10, and a plurality of such paired burner devices X are arranged at required intervals in the furnace length direction of the furnace 10.

[0062] In the industrial furnace shown in Figures 8 to 12, in the burner device X on one of the furnace walls 11 provided so as to face the furnace walls 11 on both sides as described above, the exhaust gas on-off valve 42a provided on the exhaust gas pipe 42 is closed, while the air on-off valve 41a provided on the air supply pipe 41 is opened, and air (Air) is introduced into the heat storage section 40 and heated by the heat stored in the heat storage material, and the heated air (Air) is ejected into the furnace 10 from the air ejection port 21 through the air guide pipe 20, and fuel (G) is ejected from each fuel ejection nozzle 30 on both sides of the air ejection port 21, and the heated air (Air) and fuel (G) are mixed into the furnace 10. 0, while the burner device X on the opposite furnace wall 11 prevents fuel G from being ejected from each fuel ejection nozzle 30 on both sides of the air ejection port 21. The air on-off valve 41 a provided on the air supply pipe 41 is closed, while the exhaust gas on-off valve 42 a provided on the exhaust gas pipe 42 is opened, so that the combustion exhaust gas Ga after the fuel G has been burned is guided from inside the furnace 10 through the air ejection port 21 into the heat storage section 40, and the heat of the combustion exhaust gas Ga is stored in the heat storage material in the heat storage section 40, after which the combustion exhaust gas Ga is exhausted through the exhaust gas pipe 42, thereby performing a heat storage operation.

[0063] The burner devices X, which are provided in pairs facing each other on both sides of the furnace wall 11, alternate between the combustion operation and the heat storage operation. In this way, the combustion air Air can be preheated by the heat of the combustion exhaust gas Ga after combustion via the heat storage section 40, thereby saving fuel.

[0064] In the industrial furnaces shown in Figures 8 to 11, in each of the burner devices X arranged adjacent to each other in the furnace length direction of the furnace 10, the flow direction of the combustion exhaust gas Ga (see arrows in the figures) is opposite for each pair in the furnace length direction, so that there is no temperature imbalance in the furnace, and the combustion operation and the heat storage operation are alternately switched over.

[0065] In the industrial furnace shown in FIG. 8(A), in each burner device X that performs combustion and is provided on the furnace walls 11 on both sides, the control device 36 closes the short flame on-off valves 33b in each fuel injection nozzle 30 provided on both sides of the air injection port 21, while opening the long flame on-off valves 34b, so that fuel G is supplied to the long flame fuel injection nozzles 32 on both sides through the long flame fuel supply pipes 34a on both sides, and the fuel G is injected from the long flame nozzle portions 32a at the tips of the long flame fuel injection nozzles 32 on both sides toward a position away from the air injected from the air injection port 21, where it joins with the air injected from the air injection port 21 and is burned.

[0066] In the industrial furnace shown in Figure 8(A), in each burner device X that performs combustion operation and is installed on the furnace walls 11 on both sides, fuel G is ejected from the long flame nozzle portion 32a at the tip of the long flame fuel ejection nozzles 32 on both sides toward a position away from the air ejected from the air ejection port 21, and then the fuel G is merged with the air ejected from the air ejection port 21 at a position away from where it intersects with the air ejected from the air ejection port 21 and combusted, so that the temperature in the center of the furnace 10 in the furnace width direction becomes higher than the temperature on both sides in the furnace width direction, as shown in Figure 8(B).

[0067] In the industrial furnace shown in FIG. 9(A), in each burner device X that performs combustion and is provided on the furnace walls 11 on both sides, the control device 36 closes the long flame on-off valves 34b in each fuel injection nozzle 30 provided on both sides of the air injection port 21, while opening the short flame on-off valves 33b, so that fuel G is supplied to the short flame fuel injection nozzles 31 on both sides through the short flame fuel supply pipes 33a on both sides, and the fuel is injected from the short flame nozzle portions 31a at the tips of the short flame fuel injection nozzles 31 on both sides toward a position close to the air injected from the air injection port 21, where it joins with the air injected from the air injection port 21 at a position close to where they intersect and are burned.

[0068] In the industrial furnace shown in Figure 9(A), in each burner device X that performs combustion operation and is installed on the furnace walls 11 on both sides, fuel is ejected from the short flame nozzle portion 31a at the tip of the short flame fuel ejection nozzles 31 on both sides toward a position close to the air ejected from the air ejection port 21, and the fuel is allowed to merge with the air ejected from the air ejection port 21 at a position close to where it intersects, and combustion is carried out.As shown in Figure 9(B), the temperature on both sides of the furnace width direction within the furnace 10 will be higher than the temperature in the center of the furnace width direction.

[0069] In the industrial furnace shown in FIG. 10(A), in each burner device X that performs combustion and is provided on one furnace wall 11, the control device 36 closes the short flame on-off valve 33b in each fuel injection nozzle 30 provided on both sides of the air injection port 21, while opening the long flame on-off valve 34b, so that fuel G is supplied to the long flame fuel injection nozzles 32 on both sides through the long flame fuel supply pipes 34a on both sides, and the fuel is injected from the long flame nozzle parts 32a at the tips of the long flame fuel injection nozzles 32 on both sides toward a position away from the air injected from the air injection port 21, and the fuel joins with the air injected from the air injection port 21 at a position away from the air injection port 21. Meanwhile, in each burner device X that is provided on the opposite furnace wall 11 and performs combustion operation, the control device 36 closes the long flame on-off valves 34b in each fuel injection nozzle 30 provided on both sides of the air injection port 21, while opening the short flame on-off valves 33b, so that fuel G is supplied to the short flame fuel injection nozzles 31 on both sides through the short flame fuel supply pipes 33a on both sides, and the fuel is injected from the short flame nozzle parts 31a at the tips of the short flame fuel injection nozzles 31 on both sides toward a position close to the air injected from the air injection port 21, where it joins with the air injected from the air injection port 21 and is burned.

[0070] 10(A), in each burner device X that performs combustion and is provided on one furnace wall 11, fuel is ejected from the long flame nozzle portions 32a at the tips of the long flame fuel ejection nozzles 32 on both sides toward a position away from the air ejected from the air ejection ports 21, and the fuel is merged with the air ejected from the air ejection ports 21 at a position away from where the fuel intersects with the air ejected from the air ejection ports 21, and combusted. On the other hand, in each burner device X that performs combustion and is provided on the opposite furnace wall 11, fuel G is ejected from the short flame nozzle portions 31a at the tips of the short flame fuel ejection nozzles 31 on both sides toward a position away from the air ejection ports 21, and combusted. When the fuel G is jetted toward a position close to the air jetted from the outlet 21 and then merges with the air jetted from the air jet outlet 21 at a position close to where they intersect and are combusted, as shown in Figure 10 (B), the temperature inside the furnace 10 near the furnace wall 11 on the opposite side where the fuel G is combusted near the air jetted from the air jet outlet 21 becomes higher than the temperature inside the furnace 10 near the furnace wall 11 on one side where the fuel G is combusted at a position away from the air jetted from the air jet outlet 21, creating a gradient in the temperature distribution inside the furnace 10.

[0071] This can be utilized when heating a steel billet (not shown) by gradually changing the temperature across the width of the furnace (gradient heating).

[0072] In the industrial furnace shown in FIG. 11(A), in each burner device X that performs combustion and is provided on the furnace walls 11 on both sides, the control device 36 closes the long flame on-off valve 34b in the fuel injection nozzle 30 provided on one side of the air injection port 21, while opening the short flame on-off valve 33b, so that fuel G is supplied to the short flame fuel injection nozzle 31 through the short flame fuel supply pipe 33a, and fuel G is directed from the short flame nozzle part 31a at the tip of the short flame fuel injection nozzle 31 to a position close to the air injected from the air injection port 21. The short flame on-off valve 33b in the fuel injection nozzle 30 provided on the opposite side of the air injection port 21 is closed, while the long flame on-off valve 34b is opened to supply fuel G to the long flame fuel injection nozzle 32 through the long flame fuel supply pipe 34a, and the fuel G is injected from the long flame nozzle part 32a at the tip of the long flame fuel injection nozzle 32 toward a position away from the air injected from the air injection port 21, so that the fuel G is burned at a position away from the air injected from the air injection port 21.

[0073] 11(A), in each burner device X provided on the furnace walls 11 on both sides performing combustion operation, the fuel injection nozzle 30 on one side of the air outlet 21 ejects fuel G from the short flame nozzle section 31a at the tip of the short flame fuel injection nozzle 31, causing combustion at a position close to the air injected from the air outlet 21, and in the fuel injection nozzle 30 on the opposite side of the air outlet 21 ejects fuel G from the long flame nozzle section 32a at the tip of the long flame fuel injection nozzle 32, causing combustion at a position distant from the air injected from the air outlet 21. In this way, in each burner device X provided on the furnace walls 11 on both sides performing combustion operation, combustion is carried out with a combination of long flames and short flames, and as shown in FIG. 11(B), the temperature change in the furnace 10 in the furnace width direction is reduced, making it possible to heat the furnace 10 to a constant temperature. Furthermore, although not shown here, even if both the short flame on-off valve 33b and the long flame on-off valve 34b are opened in the fuel injection nozzles 30 on both sides, the fuel G can be burned at positions close to and far from the air outlet 21, as in the case shown in Figure 6 (B) above, and the temperature at each position in the furnace 10 can be easily controlled, and the temperature difference between the positions close to and far from the air outlet 21 can be reduced, or the temperature can be changed as desired.

[0074] Furthermore, it becomes easy to change the point at which the object is heated by adjusting the length of the flame, and to adjust the temperature distribution within the furnace.

[0075] In industrial furnaces such as the continuous heating furnaces shown in Figures 8 to 11, the combustion operation and the heat storage operation are alternately performed while the flow direction of the combustion exhaust gas Ga (see arrows in the figures) is opposite for every pair of burner devices X arranged adjacent to each other in the furnace length direction of the furnace 10 so as to prevent temperature imbalances within the furnace. However, as in the industrial furnace shown in Figure 12, the combustion operation and the heat storage operation may be alternately performed while the flow direction of the combustion exhaust gas Ga (see arrows in the figure) is opposite for every two pairs of burner devices X arranged adjacent to each other in the furnace length direction of the furnace 10.

[0076] Therefore, the contents shown in Figures 8 to 12 do not have to be decided upon as one during operation of the furnace 10, but rather multiple items may be combined and operation may be carried out while changing the order and time depending on the situation.

[0077] REFERENCE SIGNS LIST 10: Furnace 11: Furnace wall 20: Air guide pipe 21: Air outlet 30: Fuel ejection nozzle 31: Short flame fuel ejection nozzle 31a: Short flame nozzle section 32: Long flame fuel ejection nozzle 32a: Long flame nozzle section 33a: Short flame fuel supply pipe 33b: Short flame on / off valve 33c: Short flame adjustment valve 34a: Long flame fuel supply pipe 34b: Long flame on / off valve 34c: Long flame adjustment valve 36: Control device 40: Thermal storage section 41: Air supply pipe 41a: Air on / off valve 42: Exhaust gas pipe 42a: Exhaust gas on / off valve Air: Air G: Fuel Ga: Combustion exhaust gas X: Burner device

Claims

1. In a burner device that mixes and burns air ejected from an air ejection port and fuel ejected from a fuel ejection nozzle, a short-flame fuel ejection nozzle for mixing and burning fuel at a position close to the air ejected from the air ejection port and a long-flame fuel ejection nozzle for mixing and burning fuel at a position distant from the air ejected from the air ejection port are provided in the fuel ejection nozzle. A burner device characterized by this.

2. In the burner device according to claim 1, at least one of the angle at which fuel is ejected from the short-flame nozzle portion at the tip of the short-flame fuel ejection nozzle toward the air ejected from the air ejection port and the angle at which fuel is ejected from the long-flame nozzle portion at the tip of the long-flame fuel ejection nozzle toward the air ejected from the air ejection port is adjusted. A burner device characterized by this.

3. In the burner device according to claim 1, switching means for switching the fuel ejection nozzle for ejecting fuel between the short-flame fuel ejection nozzle and the long-flame fuel ejection nozzle is provided. A burner device characterized by this.

4. In the burner device according to claim 1, a short-flame adjustment valve for adjusting the amount of fuel led to the short-flame fuel ejection nozzle and a long-flame adjustment valve for adjusting the amount of fuel led to the long-flame fuel ejection nozzle are provided. A burner device characterized by this.

5. In the burner device according to claim 1, the fuel ejection nozzle provided with the short-flame fuel ejection nozzle and the long-flame fuel ejection nozzle is provided symmetrically on both sides of the air ejection port for ejecting air. A burner device characterized by this.

6. In the burner device according to claim 1, a heat storage portion in which a heat storage material is accommodated is provided in an air guide pipe for guiding air to the air ejection port. A burner device characterized by this.

7. In an industrial furnace provided with a burner device that mixes and burns air ejected from an air ejection port and fuel ejected from a fuel ejection nozzle on a furnace wall, as the burner device, the burner device according to any one of claims 1 to 6 is provided. An industrial furnace characterized by this.

8. In the industrial furnace according to claim 7, a plurality of the burner devices are provided on the furnace walls on both sides. An industrial furnace characterized by this.

9. In an industrial furnace provided with a burner device on a furnace wall for mixing and burning air ejected from an air outlet and fuel ejected from a fuel injection nozzle, as the burner device, the burner device according to claim 6 is used, and combustion exhaust gas after being burned in the furnace is guided through the air outlet to a heat storage section provided in an air guide pipe to store the heat of the combustion exhaust gas in a heat storage material accommodated in the heat storage section. On the other hand, air heated by the heat storage material stored in the heat storage section is guided to the air outlet by the air guide pipe and ejected into the furnace. An industrial furnace characterized by this.

10. In the industrial furnace according to claim 9, a plurality of the burner devices are provided on both side furnace walls. In each burner device, combustion exhaust gas after being burned in the furnace is guided through the air outlet to the heat storage section provided in the air guide pipe to store the heat of the combustion exhaust gas in a heat storage material accommodated in the heat storage section. A heat storage operation is performed, and an air heating operation in which air heated by the heat storage material stored in the heat storage section is ejected from the air outlet into the furnace and burned is alternately performed. An industrial furnace characterized by this.

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