Control method for industrial furnace

Abstract

The burner device (X) of the present invention mixes and burns air ejected from the air outlet (21) and fuel ejected from the fuel nozzle (30). The fuel nozzle is provided with a short flame fuel nozzle (31) for mixing and burning the fuel with the air ejected from the air outlet at a close position; and a long flame fuel nozzle (32) for mixing and burning the fuel with the air ejected from the air outlet at a far position.

Description

Burner device and industrial furnace The present invention relates to a burner device and an industrial furnace using the burner device. The burner device mixes and burns air ejected from an air outlet and fuel ejected from a fuel nozzle. In particular, the burner device has the following features: The position at which the air ejected from the air outlet and the fuel ejected from the fuel nozzle are mixed and burned can be easily adjusted. In an industrial furnace using the burner device, the position at which the air ejected from the air outlet and the fuel ejected from the fuel nozzle are mixed and burned can be changed, thereby easily adjusting the temperature distribution characteristics within the furnace and achieving appropriate heating of the workpiece within the furnace. Conventionally, industrial furnaces such as continuous heating furnaces, soaking furnaces, melting furnaces, and heat treatment furnaces generally employ burner devices that mix and combust air ejected from air ejection ports and fuel ejected from fuel ejection nozzles. Furthermore, in order to save energy, such a burner device may be a heat storage type burner device provided with a heat storage portion to recover the heat of the combustion gas burned in the furnace and to heat the combustion air. Furthermore, in an industrial furnace using the aforementioned burner device, when the material to be processed is heated, there may be situations where the entire material to be processed needs to be heated uniformly or one side of the material to be processed needs to be heated strongly. In this case, the temperature distribution in the furnace must be adjusted. Furthermore, in order to adjust the temperature distribution in the furnace as described above, Patent Document 1 proposes the following technology: primary fuel is ejected from the combustion air supply port of the regenerative burner, and secondary fuel is ejected into the furnace from the secondary fuel nozzle, and the supply ratio of the primary fuel to the secondary fuel is controlled. However, the technology disclosed in the aforementioned patent document 1 adjusts the temperature distribution in the furnace by controlling the supply ratio of the primary fuel to the secondary fuel. Therefore, if the combustion amount of the primary fuel is increased, the problem of increased NOx (nitrogen oxides) during combustion will occur. Moreover, this technology causes the secondary fuel to be ejected in parallel with the combustion air, so that the flame produced by the secondary combustion will be formed into a long flame, making it extremely difficult to adjust the temperature distribution at various positions in the furnace while maintaining the overall combustion amount in the furnace fixed. In addition, Patent Document 2 proposes the following technology: a primary fuel nozzle is arranged in a nozzle of combustion air so as to be ejected from around the airflow of combustion air, and a plurality of secondary fuel nozzles are arranged. For these secondary fuel nozzles, a flame-maintaining mechanism is provided at the nozzle outlet at the front end of the piping, which includes a flow path for supplying flame-maintaining air from around the ejected secondary fuel, and is constructed so as to be able to blow directly into the furnace from a place different from the combustion air in a manner roughly parallel to the combustion air nozzle, and secondary fuel flow regulating valves are respectively provided to change the flame temperature distribution. However, in the technology disclosed in the aforementioned patent document 2, if the combustion amount of the primary fuel ejected from the primary fuel nozzle is increased, the problem of increased NOx during combustion will still occur. In addition, since this technology causes the secondary fuel to be ejected from each secondary fuel nozzle in parallel with the combustion air, and the temperature distribution in the furnace is adjusted by controlling the ratio of the amount of primary fuel ejected from the primary fuel nozzle to the ratio of each secondary fuel ejected from each secondary fuel nozzle, there is also the problem of making it extremely difficult to adjust the temperature distribution at various positions in the furnace while maintaining the overall combustion amount in the furnace fixed. In addition, Patent Document 3 proposes the following technology: in a regeneration burner device, each burner has an air nozzle for ejecting air and a plurality of fuel nozzles for ejecting fuel, and the aforementioned plurality of fuel nozzles have more than two ejection directions, and in the operating method of the regeneration burner device, the ejection amounts of the aforementioned plurality of fuel nozzles are changed respectively, thereby changing the high-temperature area belonging to the combustion gas temperature, that is, the position of the temperature peak. However, in the technology disclosed in the aforementioned patent document 3, a plurality of fuel injection nozzles with different injection directions are provided at different positions of the furnace, and therefore a fuel supply port corresponding to each fuel injection nozzle is required, which will impose restrictions on the position of each fuel injection nozzle installed in the furnace, and it is necessary to separately provide equipment such as piping for supplying fuel to each fuel injection nozzle, which increases the equipment cost. In addition, there will be problems such as complicating the control of the fuel supplied to each fuel injection nozzle. In addition, the scrap metal melting furnace of Patent Document 4 is provided with: a main burner that sprays a flame (long flame) toward the pile of scrap metal; and an auxiliary burner that sprays a short flame for melting the scrap metal accumulated in front of the main burner; and while observing the melting state, the contact point of the flame is changed at any time to a distant or near position so that the scrap metal is melted evenly. However, the technology disclosed in Patent Document 4 requires multiple dedicated burners to change the heating point where the flame contacts the accumulated scrap metal to near and far locations, which increases the cost of parts, complicates the structure, and requires space around the device. [Prior Art Literature] [Patent Document] Patent Document 1: Japanese Patent Application Laid-Open No. 9-145047 Patent Document 2: Japanese Patent Application Laid-Open No. 2003-74834 Patent Document 3: Japanese Patent Gazette No. 6764000 Patent Document 4: Japanese Patent Application Laid-Open No. 11-325734 The present invention aims to solve the above-mentioned problems in a burner device and an industrial furnace using the burner device, wherein the burner device mixes air ejected from an air ejection port and fuel ejected from a fuel ejection nozzle to burn the mixture. Specifically, the problem is that: in the aforementioned combustion device, the position at which the air ejected from the air ejection port and the fuel ejected from the fuel ejection nozzle are mixed and burned can be simply adjusted; in an industrial furnace using such a burner device, the position at which the air ejected from the air ejection port and the fuel ejected from the fuel ejection nozzle are mixed and burned can be changed; the length of the flame can be simply changed to change the heating point and adjust the temperature distribution in the furnace so that the processed material can be properly heated in the furnace. In the burner device of the present invention, in order to solve the above-mentioned problems, in the burner device that mixes the air ejected from the air ejection port and the fuel ejected from the fuel ejection nozzle for combustion, the above-mentioned fuel ejection nozzle is provided with: a short flame fuel ejection nozzle that mixes the fuel with the air ejected from the above-mentioned air ejection port at a close position and burns; and a long flame fuel ejection nozzle that mixes the fuel with the air ejected from the above-mentioned air ejection port at a distant position and burns. Furthermore, if, as in the burner device of the present invention, a single fuel ejection nozzle is provided with a short-flame fuel ejection nozzle that mixes fuel with air ejected from the aforementioned air ejection port at a close position and burns, and a long-flame fuel ejection nozzle that mixes fuel with air ejected from the aforementioned air ejection port at a distant position and burns, then there is no need to install a plurality of fuel ejection nozzles with different ejection directions at different positions in the furnace, as shown in Patent Documents 3 and 4. As a result, there is no need to provide fuel supply ports corresponding to each fuel ejection nozzle in the furnace, eliminating the need for restrictions on the location of each fuel ejection nozzle in the furnace, the need for additional piping to supply fuel to each separately installed fuel ejection nozzle, and the resulting increase in equipment cost and complexity in the control of the fuel supplied to each fuel ejection nozzle. Furthermore, the burner device of the present invention may be configured to adjust the angle of at least one of the following: the angle at which fuel is ejected from the short flame nozzle portion at the front end 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 front end of the long flame fuel ejection nozzle toward the air ejected from the air ejection port. This allows for easy adjustment of the position at which the fuel ejected from the short flame fuel ejection nozzle mixes with the air ejected from the air ejection port and burns, and the position at which the fuel ejected from the long flame fuel ejection nozzle mixes with the air ejected from the air ejection port and burns. Furthermore, while the angle adjustment method is omitted from the figure, the short flame nozzle portion and the long flame nozzle portion, which eject fuel, may be mechanically moved externally to change the angle, or the short flame nozzle portion and the long flame nozzle portion may be manually replaced with components that have different ejection angles. Furthermore, the burner device of the present invention may be provided with a switching means for switching the fuel injection nozzle between the short flame fuel injection nozzle and the long flame fuel injection nozzle, wherein the fuel injection nozzle injects fuel. This makes it possible to clearly distinguish between the short flame and the long flame. Furthermore, the burner device of the present invention may be provided with a short flame regulating valve for regulating the amount of fuel directed to the short flame fuel injection nozzle, and a long flame regulating valve for regulating the amount of fuel directed to the long flame fuel injection nozzle. This allows the amount of fuel mixed with the air ejected from the air ejection port for combustion to be maintained constant, while allowing for simple adjustment of the amount of fuel ejected from the short flame fuel injection nozzle and the air ejected from the air ejection port for combustion near the air ejection port, and the amount of fuel ejected from the long flame fuel injection nozzle and the air ejected from the air ejection port for combustion far from the air ejection port. Furthermore, in the burner device of the present invention, the fuel nozzles including the short flame fuel nozzle and the long flame fuel nozzle are symmetrically arranged on both sides of the air outlet through which air is ejected. Thus, if the fuel nozzles including the short flame fuel nozzle and the long flame fuel nozzle are symmetrically arranged on both sides of the air outlet, and fuel is ejected from the short flame fuel nozzle and / or the long flame fuel nozzle on both sides, the fuel ejected from the short flame fuel nozzle and / or the long flame fuel nozzle on both sides will merge and burn at a position where it intersects with the air ejected from the air outlet. This allows the fuel to burn along the direction of air ejection, regardless of whether the flame is located near or far from the air outlet. In this way, the flame will not be tilted relative to the ejection direction of the air as in the aforementioned Patent Document 3, so the temperature in the furnace will not deviate, and a symmetrical temperature distribution can be formed relative to the ejection direction of the air. Furthermore, in the burner device of the present invention, a heat storage section containing a heat storage material may be provided in the air guide pipe that guides air to the air outlet. In this manner, the air can be heated by the heat storage material stored in the heat storage section, and the heated air can be ejected from the air outlet and mixed with the fuel ejected from the short flame fuel nozzle and / or the long flame fuel nozzle, resulting in efficient combustion. Furthermore, when combustion ceases, the exhaust gas can be directed through the air outlet to the heat storage section provided in the air guide pipe, where the heat of the exhaust gas can be stored in the heat storage material contained in the heat storage section. In this manner, the combustion air can be preheated via the heat storage portion using the heat of the exhaust gas after combustion, thereby saving fuel. Furthermore, the industrial furnace of the present invention is an industrial furnace in which a burner device is provided on the furnace wall for mixing and burning air ejected from the air ejection port and fuel ejected from the fuel ejection nozzle, wherein the burner device as described above is provided. Furthermore, in the industrial furnace of the present invention, a plurality of the aforementioned burner devices may be installed on the furnace walls on both sides. In addition, the industrial furnace of the present invention is an industrial furnace in which a burner device is provided on the furnace wall to mix and burn air ejected from an air outlet and fuel ejected from a fuel ejection nozzle, wherein a burner device is used in which a heat storage portion containing a heat storage material is provided in an air guide pipe that guides air to the aforementioned air outlet as the aforementioned burner device, and is composed so that the combustion exhaust gas after combustion in the furnace can be guided to the aforementioned heat storage portion provided in the aforementioned air guide pipe through the aforementioned air outlet, and the heat of the combustion exhaust gas can be stored in the heat storage material contained in the heat storage portion, and on the other hand, the air heated by the heat storage material that has stored heat in the aforementioned heat storage portion is guided to the air outlet by the aforementioned air guide pipe and ejected into the furnace. In this way, the air can be heated by the heat storage material that has stored heat in the heat storage section as mentioned above, and the heated air can be ejected from the above-mentioned air outlet and mixed with the fuel ejected from the above-mentioned short flame fuel ejection nozzle and / or long flame fuel ejection nozzle to be effectively burned. On the other hand, when the combustion stops, the combustion exhaust gas after combustion can be guided to the heat storage section provided in the above-mentioned air guide pipe through the above-mentioned air outlet, and the heat of the combustion exhaust gas can be stored in the heat storage material accommodated in the heat storage section. Here, if the fuel ejection nozzles including the fuel ejection nozzle for the short flame and the fuel ejection nozzle for the long flame are symmetrically arranged on both sides of the aforementioned air ejection port for ejecting air, the flame will not be tilted relative to the ejection direction of the air as in the aforementioned patent document 3, so the temperature in the furnace will not deviate, and a symmetrical temperature distribution can be formed relative to the ejection direction of the air. Furthermore, in the industrial furnace of the present invention, when a burner device having a heat storage portion containing a heat storage material provided in the air guide duct for guiding air to the air outlet is used as the burner device as described above, a plurality of the burner devices can be provided on the furnace walls on both sides, and heat storage action and combustion action are alternately performed in each burner device. The heat storage action is to guide the combustion exhaust gas after combustion in the furnace to the heat storage portion provided in the air guide duct through the air outlet provided in one furnace wall, and to store the heat of the combustion exhaust gas in the heat storage material contained in the heat storage portion. The combustion action is to cause the air heated by the heat storage material having stored heat in the heat storage portion to be ejected into the furnace from the air outlet provided in the other furnace wall to be burned. In this way, a group of two burner devices are arranged on both sides of the furnace wall in a facing manner, so that heat storage action and combustion action can be performed alternately. The optimal temperature distribution can be obtained in the industrial furnace equipped with the above-mentioned burner device, and continuous operation can be performed to save fuel, thereby achieving energy saving. If, as in the burner device of the present invention, a short flame fuel injection nozzle is provided in a fuel injection nozzle so that the fuel is mixed with the air ejected from the aforementioned air injection port at a close position and burns, and a long flame fuel injection nozzle so that the fuel is mixed with the air ejected from the aforementioned air injection port at a distant position and burns, then the position at which the air ejected from the air injection port and the fuel ejected from the fuel injection nozzle are mixed and burned can be easily adjusted by using simple equipment, and the operating conditions can be changed during operation without stopping the equipment. In addition, the industrial furnace of the present invention uses a burner device as described above, so the position where the air ejected from the air outlet and the fuel ejected from the fuel ejection nozzle are mixed and burned is changed. By doing so, the length of the flame can be simply adjusted to change the heating point of the heated object and adjust the temperature distribution in the furnace. Furthermore, since these configurations can be realized by a single fuel injection nozzle, the structure does not become complicated and space around the device can be secured. 10: Furnace 11: Furnace wall 20: Air guide tube 21: Air outlet 30: Fuel injection nozzle 31: Short flame fuel injection nozzle 31a: Short flame nozzle 32: Long flame fuel injection nozzle 32a: Long flame nozzle 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: Heat storage unit 41: Air supply pipe 41a: Air opening and closing valve 42: Exhaust pipe 42a: Exhaust opening and closing valve Air: G: Fuel Ga: combustion exhaust X: Burner device Figure 1 is a schematic diagram showing the following state: in the burner device and industrial furnace of embodiment 1 of the present invention, a fuel injection nozzle provided with a short flame fuel injection nozzle and a long flame fuel injection nozzle is arranged on one side of the air injection port, so that the fuel is ejected into the furnace from the long flame fuel injection nozzle arranged in the fuel injection nozzle and mixed with the air ejected from the air injection port at a position away from the furnace wall to cause the fuel to burn. Figure 2 is a schematic diagram showing the following state: in the burner device and industrial furnace of the aforementioned embodiment 1, the fuel is sprayed into the furnace from the short flame fuel injection nozzle set in the fuel injection nozzle, and is mixed with the air ejected from the air outlet at a position close to the furnace wall to cause the fuel to burn. Figure 3 is a schematic diagram showing the following state: in the modified example of the burner device and the industrial furnace of the aforementioned embodiment 1, a short flame regulating valve for adjusting the amount of fuel supplied to the short flame fuel injection nozzle is provided on the short flame fuel supply pipe, and a long flame regulating valve for adjusting the amount of fuel supplied to the long flame fuel injection nozzle is provided on the long flame fuel supply pipe, and the amount of fuel ejected from the short flame fuel injection nozzle and the amount of fuel ejected from the long flame fuel injection nozzle are adjusted to perform combustion. Figure 4 is a schematic diagram showing the following state: in the burner device and industrial furnace of the aforementioned embodiment 2, the fuel injection nozzles provided with short flame fuel injection nozzles and long flame fuel injection nozzles are symmetrically arranged on both sides of the air injection port, so that the fuel is sprayed into the furnace from the short flame fuel injection nozzles in each fuel injection nozzle provided on both sides of the air injection port, and is mixed with the air ejected from the air injection port at a position close to the furnace wall to cause the fuel to burn. Figure 5 is a schematic diagram showing the following state: in the burner device and industrial furnace of the aforementioned embodiment 2, the fuel is sprayed into the furnace from the long flame fuel nozzles in each fuel nozzle arranged on both sides of the air nozzle, and is mixed with the air sprayed from the air nozzle at a position away from the furnace wall to cause the fuel to burn. Figure 6 shows the burner device and industrial furnace of the aforementioned embodiment 2, wherein Figure 6(A) is a schematic explanatory diagram showing the following state: fuel is sprayed into the furnace from the short flame fuel spray nozzle in the fuel spray nozzle arranged on one side of the air ejection port, and fuel is sprayed into the furnace from the long flame fuel spray nozzle in the fuel spray nozzle arranged on the opposite side of the air ejection port, and is mixed with the air ejected from the air ejection port at two positions, a position close to the furnace wall and a position away from the furnace wall, so that the fuel is burned; Figure 6(B) is a schematic explanatory diagram showing the following state: fuel is sprayed into the furnace from the short flame fuel spray nozzle and the long flame fuel spray nozzle in the fuel spray nozzles arranged on both sides of the air ejection port, and is mixed with the air ejected from the air ejection port at two positions, a position close to the furnace wall and a position away from the furnace wall, so that the fuel is burned, and the amount of fuel ejected from the short flame fuel spray nozzle and the amount of fuel ejected from the long flame fuel spray nozzle are adjusted to perform combustion. Figure 7 is a schematic diagram showing the following state: In the burner device and industrial furnace of embodiment 3 of the present invention, the burner device used is formed so that the fuel injection nozzles provided with short flame fuel injection nozzles and long flame fuel injection nozzles are symmetrically arranged on both sides of the air injection port, and the air guide pipe that guides the air to the air injection port is provided with a heat storage portion that accommodates a heat storage material, and the above-mentioned burner devices are arranged on the furnace walls on both sides in a facing manner. FIG8 shows a burner device and an industrial furnace of the aforementioned embodiment 3, wherein FIG8(A) is a schematic diagram illustrating the following state: in a pair of burner devices facing each other arranged on the furnace walls on both sides, the heat storage action is to guide the exhaust gas after combustion in the furnace through the aforementioned air outlet to the aforementioned heat storage section arranged in the aforementioned air guide pipe, and the heat of the exhaust gas is stored in the heat storage material accommodated in the heat storage section; the combustion action is to cause the air heated by the heat storage material that has stored heat in the aforementioned heat storage section to be ejected from the aforementioned air outlet into the furnace to cause the fuel to burn; when the heat storage action and the combustion action are performed alternately, during the combustion action, the fuel is ejected from the long flame fuel ejection nozzles in each fuel ejection nozzle arranged on both sides of the aforementioned air outlet into the furnace, and is mixed with the heated air ejected from the air outlet at a position away from the furnace wall to cause the fuel to burn; FIG8(B) is a schematic diagram illustrating the temperature distribution in the furnace. FIG9 shows a burner device and an industrial furnace of the aforementioned embodiment 3, wherein FIG9(A) is a schematic diagram illustrating the following state: in a pair of burner devices facing each other arranged on the furnace walls on both sides, the heat storage action is to guide the exhaust gas after combustion in the furnace through the aforementioned air outlet to the aforementioned heat storage section arranged in the aforementioned air guide pipe, and the heat of the exhaust gas is stored in the heat storage material accommodated in the heat storage section; the combustion action is to cause the air heated by the heat storage material that has stored heat in the aforementioned heat storage section to be ejected from the aforementioned air outlet into the furnace to cause the fuel to burn; when the heat storage action and the combustion action are performed alternately, during the combustion action, the fuel is ejected from the short flame fuel ejection nozzles in each fuel ejection nozzle arranged on both sides of the aforementioned air outlet into the furnace, and is mixed with the heated air ejected from the air outlet at a position close to the furnace wall to cause the fuel to burn; FIG9(B) is a schematic diagram illustrating the temperature distribution in the furnace. FIG10 shows a burner device and an industrial furnace of the aforementioned embodiment 3, wherein FIG10(A) is a schematic diagram showing the following state: in a pair of burner devices disposed on opposite sides of the furnace wall, the heat storage action is to guide the exhaust gas after combustion in the furnace through the aforementioned air outlet to the aforementioned heat storage portion disposed in the aforementioned air guide pipe, and to store the heat of the exhaust gas in the heat storage material contained in the heat storage portion; the combustion action is to cause the air heated by the heat storage material that has stored heat in the aforementioned heat storage portion to be ejected from the aforementioned air outlet into the furnace to burn the fuel; when the heat storage action and the combustion action are alternately performed, during the combustion action, the heat storage material disposed in the aforementioned heat storage portion is heated to a temperature of 100°C. In the burner device on the furnace wall on one side, the fuel is ejected into the furnace from the long flame fuel ejection nozzles in each fuel ejection nozzle arranged on both sides of the aforementioned air ejection port, and is mixed with the heated air ejected from the air ejection port at a position away from the furnace wall to cause the fuel to burn. On the other hand, in the burner device on the furnace wall on the opposite side, the fuel is ejected into the furnace from the short flame fuel ejection nozzles in each fuel ejection nozzle on both sides of the aforementioned air ejection port, and is mixed with the heated air ejected from the air ejection port at a position close to the furnace wall to cause the fuel to burn. Figure 10 (B) is a schematic diagram showing the temperature distribution in the furnace. FIG11 shows a burner device and an industrial furnace of the aforementioned embodiment 3, wherein FIG11(A) is a schematic diagram showing the following state: in a pair of burner devices disposed on opposite sides of the furnace wall, the heat storage operation is to guide the exhaust gas after combustion in the furnace through the aforementioned air outlet to the aforementioned heat storage part disposed in the aforementioned air guide pipe, and to store the heat of the exhaust gas in the heat storage material contained in the heat storage part, and the combustion operation is to cause the air heated by the heat storage material stored in the aforementioned heat storage part to be ejected from the aforementioned air outlet into the furnace to burn the fuel. Combustion, when heat storage action and combustion action are performed alternately, during the combustion action, fuel is sprayed into the furnace from the long flame fuel nozzle in the fuel spray nozzle arranged on one side of the aforementioned air outlet, and on the other hand, fuel is sprayed into the furnace from the short flame fuel nozzle in the fuel spray nozzle arranged on one side of the aforementioned air outlet, and the fuel is mixed with the heated air sprayed from the air outlet at a position away from the furnace wall and a position close to the furnace wall to cause the fuel to burn; Figure 11 (B) is a schematic diagram showing the temperature distribution in the furnace. FIG12 is a schematic diagram illustrating the following state of the burner device and industrial furnace of the aforementioned embodiment 3: in a pair of burner devices facing each other and arranged on the furnace walls on both sides, the heat storage operation is such that the exhaust gas after combustion in the furnace is guided through the aforementioned air outlet to the aforementioned heat storage section arranged in the aforementioned air guide duct, and the heat of the exhaust gas is stored in the heat storage material accommodated in the heat storage section. The combustion operation is such that air heated by the heat storage material that has stored heat in the aforementioned heat storage section is ejected from the aforementioned air outlet into the furnace to burn the fuel. When the heat storage operation and the combustion operation are performed alternately, the plurality of burner devices arranged on one side of the furnace wall are in the combustion operation, while the plurality of burner devices arranged on the opposite side of the furnace wall are in the heat storage operation. Hereinafter, the burner device and industrial furnace of the embodiment of the present invention will be specifically described with reference to the accompanying drawings. In addition, the burner device and industrial furnace of the present invention are not limited to the embodiment shown below, and can be implemented with appropriate changes within the scope of the invention. (Implementation Type 1) In the burner device X of the industrial furnace of embodiment 1, as shown in Figures 1 and 2, an air outlet 21 is provided on the furnace wall 11 of the furnace 10, through which air Air guided by an air guide pipe 20 is ejected into the furnace 10, and a fuel ejection nozzle 30 is provided on the furnace wall 11 near the aforementioned air ejection outlet 21 so as to be inclined toward the direction of the air Air ejected from the air ejection outlet 21, through which fuel G is ejected. Furthermore, in the aforementioned fuel injection nozzle 30, a short flame fuel injection nozzle 31 is arranged at a position on the side of the aforementioned air injection port 21, and a long flame fuel injection nozzle 32 is arranged side by side at a position farther away from the air injection port 21 than the aforementioned short flame fuel injection nozzle 31; a short flame nozzle portion 31a is provided at the front end portion of the aforementioned short flame fuel injection nozzle 31 so as to spray the fuel G toward a position close to the air Air ejected from the air injection port 21, and a long flame nozzle portion 32a is provided at the front end portion of the long flame fuel injection nozzle 32 so as to spray the fuel G toward a position away from the air Air ejected from the air injection port 21. Furthermore, in this embodiment, the short flame nozzle portion 31a and the long flame nozzle portion 32a protrude from the front ends of the short flame fuel ejection nozzle 31 and the long flame fuel ejection nozzle 32, and the respective ejection angles are tilted toward the farther side and the closer side, respectively, to clearly differentiate between the short flame and the long flame. However, although not shown in the figure, it is also possible to provide angled holes instead of protruding short flame nozzle portions 31a and long flame nozzle portions 32a. Furthermore, although not shown in the figure, if the difference between the short flame and the long flame is desired to be minimized, the short flame nozzle portions 31a and the long flame nozzle portions 32a may be untilted. In addition, the aforementioned fuel injection nozzle 30 is structured as follows: when the aforementioned short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32 for injecting fuel G are switched by switching means, a short flame on-off valve 33b is provided in the short flame fuel supply pipe 33a that supplies fuel G to the aforementioned 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 guides fuel G to the aforementioned long flame fuel injection nozzle 32, and the opening and closing of the aforementioned short flame on-off valve 33b and the long flame on-off valve 34b are controlled by the control device 36. Furthermore, as shown in FIG1 , in the burner apparatus X of embodiment 1, when the short flame on-off valve 33b is closed and the long flame on-off valve 34b is opened by the control unit 36, fuel G is supplied only to the long flame fuel ejection nozzle 32 through the long flame fuel supply pipe 34a. Fuel G is ejected from the long flame nozzle portion 32a at the front end of the long flame fuel ejection nozzle 32 toward a position away from the air Air ejected from the air ejection port 21. At this position away from the air ejection port 21, the fuel G mixes with the air Air and burns, causing the temperature within the furnace 10 at the position away from the air ejection port 21 to rise higher than the temperature near the air ejection port 21. In the figure, the short flame on-off valve 33b and the long flame on-off valve 34b are shown in black when closed, and in highlighted when opened. On the other hand, as shown in Figure 2, if the long flame on-off valve is closed by the aforementioned control device 36 and the short flame on-off valve 33b is opened on the other hand, the 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 ejected from the short flame nozzle portion 31a at the front end of the short flame fuel injection nozzle 31 toward a position close to the air Air ejected from the air outlet 21, and is mixed with the air Air at a position close to the air outlet 21 and burned, so that the temperature in the furnace 10 at a position close to the air outlet 21 is higher than the temperature at a position far from the air outlet 21. As a result, by controlling the opening and closing of the short flame on-off valve 33b and the long flame on-off valve 34b through the control device 36, 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 can be simply controlled. In addition, in the burner device X of the modified example shown in Figure 3, the short flame on-off valve 33b is set on the short flame fuel supply pipe 33a that supplies fuel G to the short flame fuel injection nozzle 31, and in addition, a short flame adjustment valve 33c is also provided for adjusting the amount of fuel G guided to the short flame fuel injection nozzle 31, and the long flame on-off valve 34b is set on the long flame fuel supply pipe 34a that supplies fuel G to the long flame fuel injection nozzle 32, and in addition, a long flame adjustment valve 34c is also provided for adjusting the amount of fuel G guided to the long flame fuel injection nozzle 32, and the short flame on-off valve 33b and the long flame on-off valve 34b are controlled by the control device 36, and the short flame adjustment valve 33c and the long flame adjustment valve 34c are controlled. Furthermore, as shown in Figure 3, in the burner device X of this modified example, the short flame on-off valve 33b and the long flame on-off valve 34b are opened by the aforementioned control device 36, and the aforementioned short flame adjustment valve 33c and the long flame adjustment valve 34c are controlled to adjust the amount of fuel G guided to the short flame fuel injection nozzle 31 through the short flame adjustment valve 33c, and the amount of fuel G guided to the long flame fuel injection nozzle 32 through the long flame adjustment valve 34c, so as to adjust the amount of fuel G ejected from the aforementioned short flame nozzle portion 31a toward a position close to the air Air ejected from the air ejection port 21, and the amount of fuel G ejected from the aforementioned long flame nozzle portion 32a toward a position away from the air Air ejected from the air ejection port 21. In this way, the amount of fuel G mixed with the air Air ejected from the air outlet 21 and burned can be maintained constant. At the same time, the amount of fuel G mixed with the air Air ejected from the air outlet 21 and burned at a position close to the air outlet 21 and the amount of fuel G mixed with the air Air ejected from the air outlet 21 and burned at a position away from the air outlet 21 can be simply adjusted. The temperature of each position in the furnace 10 can be simply controlled, the temperature change at the position close to the air outlet 21 and the position away from the air outlet 21 can be reduced, and the temperature change can be added arbitrarily. Furthermore, the length of the flame can be simply adjusted to change the heating point on the object being heated and adjust the temperature distribution within the furnace. This configuration can be utilized as a heater for a melting furnace. (Implementation Type 2) As shown in Figures 4 to 6, in the burner device X of the industrial furnace of embodiment 2, an air outlet 21 is provided on the furnace wall 11 within the furnace 10, through which air Air guided by an air guide duct 20 is ejected into the furnace 10. Furthermore, fuel ejection nozzles 30 for ejecting fuel G are symmetrically provided on both sides of the furnace wall 11 near the air outlet 21, each nozzle being inclined toward the direction of the air Air ejected from the air outlet 21. Furthermore, in each of the aforementioned fuel injection nozzles 30, similarly to the fuel injection nozzle 30 of the aforementioned embodiment 1, a short flame fuel injection nozzle 31 is provided in the fuel injection nozzle 30 at a position on the side of the aforementioned air injection port 21, and a long flame fuel injection nozzle 32 is provided side by side at a position farther away from the air injection port 21 than the aforementioned short flame fuel injection nozzle 31; a short flame nozzle portion 31a is provided at the front end portion of the aforementioned short flame fuel injection nozzle 31 so as to spray the fuel G toward a position close to the air Air ejected from the air injection port 21, and a long flame nozzle portion 32a is provided at the front end portion of the long flame fuel injection nozzle 32 so as to spray the fuel G toward a position farther away from the air Air ejected from the air injection port 21. Furthermore, each fuel injection nozzle 30 is structured as follows: when the short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32 for injecting fuel G are switched by switching means, a short flame on-off valve 33b is provided in the short flame fuel supply pipe 33a for supplying fuel G to the above-mentioned 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 for supplying fuel G to the above-mentioned each long flame fuel injection nozzle 32, and the opening and closing of the above-mentioned each short flame on-off valve 33b and each long flame on-off valve 34b is controlled by the control device 36. Furthermore, as shown in Figure 4, in the burner device X of embodiment 2, if the long flame on-off valve 34b is closed and the short flame on-off valve 33b is opened in each fuel injection nozzle 30 on both sides of the air injection port 21 by the aforementioned control device 36, the fuel G will not be guided to the long flame fuel supply pipe 34a on both sides, but will be supplied to the short flame fuel injection nozzles 31 on both sides through the short flame fuel supply pipe 33a on both sides, and the fuel G will be ejected from the short flame nozzle portion 31a at the front end portion of the short flame fuel injection nozzle 31 on both sides toward a position close to the air Air ejected from the air injection port 21, and will merge and burn at a position intersecting and close to the air Air ejected from the air injection port 21, and a flame generated by the combustion of the fuel G will be formed at a position close to the air injection port 21 along the ejection direction of the air Air. In this way, the flame will not be tilted relative to the ejection direction of the air as in the aforementioned Patent Document 3, so the temperature in the furnace will not deviate, and a symmetrical temperature distribution can be formed relative to the ejection direction of the air. 5 , in the burner device X of embodiment 2, if the short flame on-off valve 33 b is closed and the long flame on-off valve 34 b is opened in each fuel ejection nozzle 30 on both sides of the air ejection port 21 by the aforementioned control device 36, the fuel G is not guided to the short flame fuel supply pipes 33 a on both sides, but is supplied to the long flame fuel ejection nozzles 32 on both sides through the long flame fuel supply pipes 34 a on both sides, and the fuel G is ejected from the long flame nozzle portions 32 a at the front ends of the long flame fuel ejection nozzles 32 on both sides toward a position away from the air Air ejected from the air ejection port 21, and merges and burns at a position intersecting and away from the air Air ejected from the air ejection port 21, and a flame generated by the combustion of the fuel G is formed at a position away from the air ejection port 21 along the ejection direction of the air Air. In this way, similar to the above-mentioned case, the flame will not be tilted relative to the ejection direction of the air, so the temperature in the furnace will not be uneven, and a symmetrical temperature distribution can be formed relative to the ejection direction of the air. 6 (A), in the burner device X of embodiment 2, if the long flame on-off valve 34b is closed and the short flame on-off valve 33b is opened in the fuel ejection nozzle 30 on one side of the air ejection port 21 by the aforementioned control device 36, and on the other hand, the short flame on-off valve 33b is closed and the long flame on-off valve 34b is opened in the fuel ejection nozzle 30 on the opposite side of the air ejection port 21, in the fuel ejection nozzle 30 on the side where the long flame on-off valve 34b is closed, the fuel G is not guided to the long flame fuel supply pipe 34a, but is supplied to the short flame fuel supply pipe 33a through the short flame fuel supply pipe 33a. The fuel injection nozzle 31 is provided with fuel G, and the fuel G is ejected from the short flame nozzle portion 31a at the front end portion of the short flame fuel injection nozzle 31 toward a position close to the air Air ejected from the air ejection port 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 ejected from the long flame nozzle portion 32a at the front end portion of the long flame fuel injection nozzle 32 toward a position away from the air Air ejected from the air ejection port 21. As a result, as mentioned above, in the fuel injection nozzle 30 on one side where the short flame on-off valve 33b is opened and the long flame on-off valve 34b is closed, the fuel G injected from the short flame nozzle portion 31a is mixed and burned at a position close to the air Air injected from the air outlet 21, and, in the fuel injection nozzle 30 on the opposite side where the short flame on-off valve 33b is closed and the long flame on-off valve 34b is opened, the fuel G injected from the long flame nozzle portion 32a is mixed and burned at a position away from the air Air injected from the air outlet 21. Since the fuel G can be burned at positions close to the air outlet 21 and away from the air outlet 21, the temperature of each position in the furnace 10 can be simply controlled, and the temperature change can be reduced at positions close to the air outlet 21 and away from the air outlet 21, and the temperature change can be added arbitrarily. Furthermore, the length of the flame can be simply adjusted to change the heating point on the object to be heated and adjust the temperature distribution in the furnace. Moreover, 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 can be burned at positions close to the air outlet 21 and away from the air outlet 21. As in the above-mentioned situation, the temperature of each position in the furnace 10 can be simply controlled, and the temperature change can be reduced at positions close to the air outlet 21 and away from the air outlet 21. 4 to 6(B) need not necessarily be determined as one of the contents during the operation of the furnace 10, but a plurality of contents may be combined and operated while changing the order and / or time according to the situation. (Implementation Type 3) As shown in FIG7 , in the burner device X of the industrial furnace of embodiment 3, the furnace walls 11 on both sides of the furnace 10 are respectively configured similarly to the aforementioned embodiment 2. Fuel ejection nozzles 30 for ejecting fuel G are symmetrically arranged on both sides of the furnace wall 11 near the air ejection port 21 in a manner inclined toward the direction of the air Air ejected from the air ejection port 21. Within each fuel ejection nozzle 30, a short flame fuel ejection nozzle 31 is provided at a position on the air ejection port 21 side, and long flame fuel ejection nozzles 32 are provided side by side at a position farther away from the air ejection port 21 than the short flame fuel ejection nozzle 31. A short flame nozzle portion 31 a for ejecting fuel G toward a position closer to the air Air ejected from the air ejection port 21 is provided at the front end portion of the short flame fuel ejection nozzle 31, and a long flame nozzle portion 32 a for ejecting fuel G toward a position farther away from the air Air ejected from the air ejection port 21 is provided at the front end portion of the long flame fuel ejection nozzle 32. In addition, each of the aforementioned fuel injection nozzles 30 is structured as follows: when the aforementioned short flame fuel injection nozzle 31 and the long flame fuel injection nozzle 32 for injecting fuel G are switched by switching means, similar to the structure of the aforementioned embodiments 1 and 2, a short flame on-off valve 33b is provided in the short flame fuel supply pipe 33a for supplying fuel G to the aforementioned 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 for supplying fuel G to the aforementioned each long flame fuel injection nozzle 32, and the opening and closing of the aforementioned each short flame on-off valve 33b and each long flame on-off valve 34b is controlled by the control device 36. Furthermore, in the burner device X of the industrial furnace of embodiment 3, a heat storage unit 40 containing a heat storage material (not shown) is provided in each air guide pipe 20 that guides air to the air outlet 21. An air on-off valve 41a is provided in the air supply pipe 41 that supplies air Air to the heat storage unit 40. Furthermore, an exhaust on-off valve 42a is provided in the exhaust pipe 42 that discharges exhaust gas Ga after combustion of fuel G, which is stored in the heat storage material in the heat storage unit 40. The opening and closing of the air on-off valve 41a and the exhaust on-off valve 42a are controlled by the control device 36. Therefore, the burner device can also be used in such a regenerative alternating burner (regenerative regenerative burner). As shown in Figures 8 to 12, in the industrial furnace of embodiment 3, the paired burner devices X are installed in a manner facing each other on the furnace wall 11 on both sides of the furnace 10 in the furnace width direction, and a plurality of pairs of such paired burner devices X are arranged at predetermined intervals along the furnace length direction of the furnace 10. Furthermore, in the industrial furnace shown in FIG8 to FIG12, a combustion operation is performed while a heat storage operation is performed. In this combustion operation, in the burner device X provided on one side of the furnace wall 11 of both sides in a facing manner as described above, the exhaust on-off valve 42a provided on the exhaust pipe 42 is closed, and the air on-off valve 41a provided on the air supply pipe 41 is opened. The heat guided to the heat storage section 40 and stored in the heat storage material heats the air Air, and the air Air heated in this manner is ejected from the air outlet 21 into the furnace 10 through the air guide pipe 20. In addition, the fuel G is ejected from the fuel ejection nozzles 3 on both sides of the air ejection outlet 21. 0 is ejected, and the heated air Air and fuel G are burned in the furnace 10. This heat storage operation is performed in the burner device X on the furnace wall 11 on the opposite side. The fuel G is not ejected from the fuel ejection nozzles 30 on both sides of the air ejection port 21. The air on-off valve 41a provided in the air supply pipe 41 is closed, and the exhaust on-off valve 42a provided in the exhaust pipe 42 is opened. The combustion exhaust gas Ga after the fuel G is burned is guided from the furnace 10 through the air ejection port 21 into the heat storage section 40. After the heat of the combustion exhaust gas Ga is stored in the heat storage material in the heat storage section 40, the combustion exhaust gas Ga is discharged through the exhaust pipe 42. Furthermore, the burner devices X, arranged in pairs on both sides of the furnace wall 11, alternately switch between the aforementioned combustion and heat storage operations. This allows the combustion air Air to be preheated via the heat storage unit 40 using the heat from the exhaust gas Ga after combustion, thereby saving fuel. Furthermore, in the industrial furnace shown in Figures 8 to 11, in each burner device X disposed adjacent to each other along the length of the furnace 10, the flow directions of the combustion exhaust gas Ga of each pair of burner devices X are made opposite in the length of the furnace (see the arrows in the figures), while the aforementioned combustion action and heat storage action are alternately switched to prevent the temperature in the furnace from deviating. Among them, in the industrial furnace shown in Figure 8(A), in each burner device X that performs combustion action and is arranged on the furnace wall 11 on both sides, the short flame on-off valve 33b of each fuel injection nozzle 30 arranged on both sides of the air ejection port 21 is closed by the aforementioned control device 36, and on the other hand, the long flame on-off valve 34b is opened, so that the 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 ejected from the long flame nozzle part 32a at the front end part of the long flame fuel injection nozzle 32 on both sides toward a position away from the air Air ejected from the air ejection port 21, and merges and burns at a position away from the air Air ejected from the air ejection port 21. Furthermore, in an industrial furnace as shown in FIG8(A), if in each burner device X that performs combustion action provided on the furnace walls 11 on both sides, the fuel G is ejected from the long flame nozzle portion 32a at the front end portion of the long flame fuel ejection nozzle 32 on both sides toward a position away from the air Air ejected from the air ejection port 21, and when it merges and burns at a position intersecting and away from the air Air ejected from the air ejection port 21, as shown in FIG8(B), the temperature of the central portion in the furnace width direction inside the furnace 10 will become higher than the temperature of the two side portions in the furnace width direction. In addition, in the industrial furnace shown in Figure 9(A), in each burner device X that performs combustion action and is arranged on the furnace wall 11 on both sides, the long flame on-off valve 34b of each fuel ejection nozzle 30 arranged on both sides of the air ejection port 21 is closed by the aforementioned control device 36, and on the other hand, the short flame on-off valve 33b is opened, so that the fuel G is supplied to the short flame fuel ejection nozzles 31 on both sides through the short flame fuel supply pipes 33a on both sides, and the fuel is ejected from the short flame nozzle part 31a at the front end part of the short flame fuel ejection nozzle 31 on both sides toward a position close to the air Air ejected from the air ejection port 21, and merges and burns at a position where it intersects and is close to the air Air ejected from the air ejection port 21. Furthermore, in an industrial furnace as shown in FIG9(A), if in each burner device X that performs combustion action arranged on the furnace walls 11 on both sides, the fuel is ejected from the short flame nozzle portion 31a at the front end portion of the short flame fuel ejection nozzle 31 on both sides toward a position close to the air Air ejected from the air ejection port 21, and when the fuel is merged and burned at a position where it intersects and is close to the air Air ejected from the air ejection port 21, as shown in FIG9(B), the temperature of the two sides in the furnace width direction of the furnace 10 will become higher than the temperature of the center part in the furnace width direction. Furthermore, in the industrial furnace shown in FIG. 10(A), in each burner device X that performs combustion operation and is provided on the furnace wall 11 on one side, the short flame on-off valve 33b of each fuel ejection nozzle 30 provided on both sides of the air ejection port 21 is closed by the aforementioned control device 36, and on the other hand, the long flame on-off valve 34b is opened, so that the fuel G is supplied to the long flame fuel ejection nozzles 32 on both sides through the long flame fuel supply pipes 34a on both sides, and the fuel is ejected from the long flame nozzle portions 32a at the front ends of the long flame fuel ejection nozzles 32 on both sides toward a position away from the air Air ejected from the air ejection port 21, and at a position away from the air Air ejected from the air ejection port 21, the fuel G is ejected from the long flame nozzle portions 32a at the front ends of the long flame fuel ejection nozzles 32 on both sides. On the other hand, in each burner device X that performs combustion action and is arranged on the furnace wall 11 on the opposite side, the long flame on-off valve 34b of each fuel ejection nozzle 30 arranged on both sides of the air ejection port 21 is closed by the aforementioned control device 36, and on the other hand, the short flame on-off valve 33b is opened, so that the fuel G is supplied to the short flame fuel ejection nozzles 31 on both sides through the short flame fuel supply pipes 33a on both sides, and the fuel is ejected from the short flame nozzle parts 31a at the front ends of the short flame fuel ejection nozzles 31 on both sides toward a position close to the air Air ejected from the air ejection port 21, and merges and burns at a position close to the air Air ejected from the air ejection port 21. 10 (A), if, in each burner device X that performs combustion operation provided on the furnace wall 11 on one side, the long flame nozzle portion 32a at the front end portion of the long flame fuel injection nozzle 32 on both sides ejects fuel toward a position away from the air ejected from the air ejection port 21, and merges with the air ejected from the air ejection port 21 at a position where the fuel intersects and is away from the air ejected from the air ejection port 21, and burns, on the other hand, in each burner device X that performs combustion operation provided on the furnace wall 11 on the opposite side, the fuel G is ejected from the front end portion of the short flame fuel injection nozzle 31 on both sides. When the short flame nozzle portion 31a is ejected toward a position close to the air Air ejected from the air outlet 21 and merges and burns at a position where the fuel G intersects and is close to the air Air ejected from the air outlet 21, as shown in FIG10(B), the temperature inside the furnace 10 near the furnace wall 11 on the opposite side where the fuel G is burned at a position close to the air Air ejected from the air outlet 21 becomes higher than the temperature inside the furnace 10 near the furnace wall 11 on the one side mentioned before where the fuel G is burned at a position away from the air Air ejected from the air outlet 21, thereby causing the temperature distribution inside the furnace 10 to be tilted. This can be applied to the case where a steel sheet (not shown) is heated so as to gradually change its temperature along the width direction of the furnace (oblique heating). Furthermore, in the industrial furnace shown in FIG. 11(A), in each burner device X that performs combustion operation and is provided on the furnace wall 11 on both sides, the long flame on-off valve 34b of the fuel ejection nozzle 30 provided on one side of the air ejection port 21 is closed by the aforementioned control device 36, and on the other hand, the short flame on-off valve 33b is opened, so that the fuel G is supplied to the short flame fuel ejection nozzle 31 through the short flame fuel supply pipe 33a, and the fuel G is discharged from the short flame nozzle portion 31a at the front end of the short flame fuel ejection nozzle 31 toward the air ejection port 21. The air Air is ejected from the position thereof and burned, and the short flame on-off valve 33b of the fuel ejection nozzle 30 arranged on the opposite side of the air ejection port 21 is closed, and on the other hand, the long flame on-off valve 34b is opened, so that the fuel G is supplied to the long flame fuel ejection nozzle 32 through the long flame fuel supply pipe 34a, and the fuel G is ejected from the long flame nozzle portion 32a at the front end portion of the long flame fuel ejection nozzle 32 toward a position away from the air Air ejected from the air ejection port 21, and burns at a position away from the air Air ejected from the air ejection port 21. Furthermore, as shown in Figure 11(A), in the industrial furnace, in each burner device X that performs combustion action and is arranged on the furnace walls 11 on both sides, if in the fuel injection nozzle 30 on one side of the air outlet 21, the fuel G is ejected from the short flame nozzle portion 31a at the front end portion of the short flame fuel injection nozzle 31 and burns at a position close to the air Air ejected from the air outlet 21, and in the fuel injection nozzle 30 on the opposite side of the air outlet 21, the fuel G is ejected from the long flame nozzle portion 32a at the front end portion of the long flame fuel injection nozzle 32 and burns at a position away from the air Air ejected from the air outlet 21, in each burner device X that performs combustion action and is arranged on the furnace walls 11 on both sides, combustion will be performed in a state of combining long flame and short flame, and as shown in Figure 11(B), the temperature change in the furnace 10 in the furnace width direction can be reduced, and the furnace 10 can be heated to a constant temperature. In addition, although not shown in the figure, in the fuel injection nozzles 30 on both sides, even if both the short flame on-off valve 33b and the long flame on-off valve 34b are opened, the fuel G can be burned at positions close to the air outlet 21 and away from the air outlet 21, the temperature of each position in the furnace 10 can be simply controlled, the temperature change can be reduced at positions close to the air outlet 21 and away from the air outlet 21, and the temperature change can be added arbitrarily. Furthermore, the length of the flame can be simply adjusted to change the heating point on the object to be heated and adjust the temperature distribution in the furnace. 8 to 11 , the burner units X disposed adjacent to each other along the length of the furnace 10 are configured such that the flow directions of the exhaust gas Ga of each pair of burner units X are opposite in the furnace length direction (see arrows in the figures) while the combustion operation and the heat storage operation are alternately switched to prevent temperature deviation within the furnace. However, as in the industrial furnace shown in FIG. 12 , various modes of operation may be adopted depending on the situation, such as alternate switching between the combustion operation and the heat storage operation, while the flow directions of the exhaust gas Ga of each pair of burner units X are opposite in the furnace length direction (see arrows in the figures). Therefore, the contents shown in FIG. 8 to FIG. 12 do not need to be determined as one during the operation of the furnace 10, but a plurality of contents may be combined and operated while changing the order and / or time according to the situation. 10: Furnace 11: Furnace wall 20: Air guide tube 21: Air outlet 30: Fuel injection nozzle 31: Short flame fuel injection nozzle 31a: Short flame nozzle 32: Long flame fuel injection nozzle 32a: Long flame nozzle 33a: Short flame fuel supply pipe 33b: Short flame on / off valve 34a: Long flame fuel supply pipe 34b: Long flame on-off valve 36: Control device Air: G: Fuel X: Burner device

Claims

1. A method for controlling an industrial furnace, wherein in the industrial furnace to be controlled, two sets of burner devices facing each other are arranged in multiple arrays along the length of the furnace on both sides of the furnace wall. The burner devices are equipped with air outlets and fuel nozzles. The air outlets spray air, and the fuel nozzles are symmetrically arranged on both sides of the air outlets to spray fuel from both sides of the air outlets. The burner devices are also equipped with short flame fuel nozzles and long flame fuel nozzles. The short flame fuel nozzles mix the fuel with the air sprayed from the air outlets at a close position for combustion, and the long flame fuel nozzles mix the fuel with the air sprayed from the air outlets at a far position for combustion. The air guide pipe of the burner devices that guides the air to the air outlets is equipped with a heat storage section, which contains heat storage material. The control method of this industrial furnace is to control each of the aforementioned burner devices in the same group to alternately perform heat storage and combustion operations. The heat storage operation is to guide the combustion exhaust gas after combustion in the furnace through the aforementioned air outlet to the aforementioned heat storage section provided in the aforementioned air guide pipe, so that the heat of the combustion exhaust gas is stored in the heat storage material contained in the heat storage section. The combustion operation is to spray the air heated by the heat storage material stored in the aforementioned heat storage section out of the aforementioned air outlet into the furnace for combustion. Furthermore, the aforementioned burner devices arranged in multiple groups along the length of the furnace are distinguished into adjacent multiple groups. The number of groups of the aforementioned burner devices in each aforementioned group is more than one group and less than the total number of groups of the aforementioned burner devices. The aforementioned combustion operation and the aforementioned heat storage operation of the aforementioned burner devices in the same aforementioned group are switched in a unified manner, and the aforementioned combustion operation and the aforementioned heat storage operation of the aforementioned burner devices in adjacent aforementioned groups are switched alternately.

2. The control method for the industrial furnace as described in claim 1, wherein the fuel ejected from the fuel ejection nozzles located on both sides of the aforementioned air outlet is controlled so that the flame is not tilted relative to the ejection direction of the air.

3. The control method for the industrial furnace as described in claim 1 involves adjusting at least one of the angles at which fuel is ejected from the aforementioned short flame fuel ejection nozzle toward the air ejected from the aforementioned air outlet, and the angle at which fuel is ejected from the aforementioned long flame fuel ejection nozzle toward the air ejected from the aforementioned air outlet, in order to adjust the position where the fuel mixes with the air ejected from the air outlet for combustion.

4. The control method for the industrial furnace as described in claim 1, wherein the amount of fuel mixed with the air ejected from the aforementioned air outlet and burned is kept constant, while the amount of fuel guided to the aforementioned short flame fuel ejection nozzle and the amount of fuel guided to the aforementioned long flame fuel ejection nozzle are adjusted.

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