High temperature gas generator

Abstract

To provide a high temperature gas generation device capable of efficiently and stably generating a high temperature gas and miniaturizing a high temperature gas generation furnace.SOLUTION: A high temperature gas generation device comprises: a burner 10 having a combustion chamber 16 forming flame F by a fuel gas G1 and a combustion supporting gas G2 and generating a high temperature combustion gas G3 by the flame F; and a high temperature gas generation furnace 20 where one end 21 is connected to the side of the combustion chamber 16 of the burner 10, further having a cylindrical shape with a heating chamber 23 communicated with the combustion chamber 16 at the inside, and feeding respective gases G41, G42 to be pre-heated while forming the flame F at the inside of the heating chamber 23 to mix the high temperature combustion gas G3 with the respective gases G41, G42 to be pre-heated and to generate a high temperature gas G5 and exhausting the high temperature gas G5 from an exhaust port 25 arranged at the other end 22 on a side opposite the combustion chamber 16. The burner 10 forms the flame F so as to have a swirl flow and have a reverse flow area in the vicinity of the central axis J of the swirl flow.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a hot gas generating device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a method using a burner that generates a flame using a fuel gas and a combustion-supporting gas has been adopted as a method for generating high-temperature inert gas, reducing gas, and oxidizing gas that are used to form an atmosphere in, for example, the smelting of iron and non-ferrous metals and the firing process of ceramics.

[0003] As a method for generating the above-mentioned high-temperature gas, for example, a method has been proposed in which high-temperature combustion gas is generated by a burner installed in a cylindrical high-temperature gas generating furnace, and this high-temperature combustion gas is mixed with a preheated gas to generate high-temperature gas (see, for example, Patent Document 1). In the method disclosed in Patent Document 1, the preheated gas is divided into a primary preheated gas and a secondary preheated gas, the primary preheated gas is ejected in a tangential direction from the inner wall of the furnace near the burner, and the secondary preheated gas is ejected downstream toward the central axis (see Figures 3 to 5 in Patent Document 1). As a result, the high-temperature combustion flame formed by the burner, which travels along the central axis of the high-temperature gas generating furnace, collides with the secondary preheated gas, causing stagnation in the flow of the combustion gas, which lengthens the reaction time and promotes combustion, while at the same time promoting mixing of the high-temperature combustion gas with each preheated gas.

[0004] Patent Document 1 also describes a method in which primary preheated gas is ejected from the outer periphery of a burner, and secondary preheated gas is ejected from the inner wall of a high-temperature gas generator toward the central axis (see Figures 8 and 9 in Patent Document 1). As a result, as in the above, the high-temperature combustion flame formed by the burner proceeding along the central axis of the high-temperature gas generator collides with the secondary preheated gas, causing stagnation in the flow of the combustion gas, which lengthens the reaction time and promotes combustion, while at the same time promoting mixing of the high-temperature combustion gas and each preheated gas.

[0005] As described above, in all of the methods described in Patent Document 1, the high-temperature combustion flame formed by the burner is collided with the secondary preheated gas to cause stagnation in the flow of the combustion gas and lengthen the reaction time, thereby promoting both combustion and mixing of the high-temperature combustion gas with each preheated gas. According to Patent Document 1, it is said that high-temperature gas can be generated in a furnace that is more compact than conventional furnaces.

[0006] However, if a compact high-temperature gas generator is used to eject secondary preheated gas toward a high-temperature combustion flame, there is a concern that the secondary preheated gas may flow back toward the burner, making the combustion state of the flame formed by the burner unstable or making it impossible to maintain the combustion state. 3 When a fuel having a low calorific value, such as that below, is used, the above-mentioned problems associated with the backflow of the secondary preheated gas occur significantly.

[0007] In addition, there was a problem that the high-temperature combustion flame that collided with the secondary preheated gas flowed toward the furnace wall, causing the furnace wall to become very hot, causing the refractory material that makes up the high-temperature gas generating furnace to melt and shorten the furnace's lifespan. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 3378891 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been made in consideration of the above problems, and has an object to provide a high-temperature gas generation device that can generate high-temperature gas efficiently and stably and that can reduce the size of a high-temperature gas generating furnace. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention includes the following aspects. That is, the invention of claim 1 is a high-temperature gas generating apparatus comprising: a burner having a combustion chamber in which a flame is formed by a fuel gas and a combustion-supporting gas, and generating high-temperature combustion gas by the flame; and a high-temperature gas generating furnace having one end connected to the combustion chamber side of the burner and having a cylindrical shape with an internal heating chamber communicating with the combustion chamber, and supplying preheated gas while forming the flame in the heating chamber, thereby mixing the high-temperature combustion gas and the preheated gas to generate high-temperature gas, and discharging the high-temperature gas from an exhaust port located at the other end opposite the combustion chamber, wherein the burner forms the flame so as to have a swirling flow and to have a backflow area near the central axis of the swirling flow.

[0011] The invention of claim 2 is the high-temperature gas generating apparatus of claim 1, wherein the burner has a combustion chamber having a bottomed conical shape with an opening that expands in diameter at the tip side in the direction of flame formation, a fuel gas outlet opening at the bottom of the combustion chamber for ejecting the fuel gas in a swirling flow along the central axis of the burner, and further, a combustion supporting gas outlet opening at one or more positions on the inner surface of the combustion chamber for ejecting the combustion supporting gas into the interior of the combustion chamber, and the combustion supporting gas is ejected toward the fuel gas in a tangential direction to the swirling flow of the fuel gas, thereby forming a backflow area near the central axis of the swirling flow of the fuel gas.

[0012] The invention of claim 3 is a high-temperature gas generating apparatus as described in claim 2, characterized in that the fuel gas outlet is provided with swirling vanes that eject the fuel gas as a swirling flow.

[0013] Moreover, the invention according to claim 4 is a high-temperature gas generating apparatus as described in claim 3, characterized in that the swirl vane has a plurality of blade portions arranged at an angle with respect to the central axis of the fuel gas outlet.

[0014] The invention according to claim 5 is a high-temperature gas generation apparatus according to any one of claims 2 to 4, characterized in that the burner has a swirl number at the fuel gas outlet of 0.65 or more.

[0015] The invention according to claim 6 is a high-temperature gas generating apparatus according to any one of claims 2 to 5, wherein the burner has a first combustion supporting gas outlet that ejects a first combustion supporting gas as the combustion supporting gas and a second combustion supporting gas outlet that ejects a second combustion supporting gas as the combustion supporting gas, the first combustion supporting gas outlet opens to the bottom of the combustion chamber and is arranged on the central axis of the burner so as to be surrounded by the fuel gas outlet in a planar view, ejecting the first combustion supporting gas along the central axis of the burner, and the second combustion supporting gas outlet is arranged on a side wall of the combustion chamber and ejects the second combustion supporting gas toward the fuel gas and the first combustion supporting gas.

[0016] The invention according to claim 7 is the high-temperature gas generating apparatus according to any one of claims 1 to 6, characterized in that a primary preheated gas supply port for supplying a primary preheated gas as the preheated gas and a secondary preheated gas supply port for supplying a secondary preheated gas as the preheated gas are opened inside the heating chamber, the primary preheated gas supply port is arranged at a position on one end side of the high-temperature gas generating furnace where the primary preheated gas is ejected from the outer periphery of the burner toward the inside of the heating chamber, and the secondary preheated gas supply ports are arranged on the same cross section at at least three or more points on the inner surface of the heating chamber at positions where the secondary preheated gas is ejected toward the central axis of the high-temperature gas generating furnace, and the secondary preheated gases are collided with each other near the central axis of the high-temperature gas generating furnace to form an airflow toward the burner connected to the one end and an airflow toward the exhaust port arranged at the other end.

[0017] The invention of claim 8 is a high-temperature gas generation apparatus as described in claim 7, characterized in that the ratio [L1 / D] of the furnace inner length L1 in the direction along the flame formation direction to the furnace inner diameter D of the heating chamber is in the range of 1 to 3.

[0018] The invention of claim 9 is the high-temperature gas generating apparatus of claim 8, characterized in that the ratio [L2 / D] of the distance L2 from the one end connected to the burner to the secondary preheated gas supply port of the heating chamber to the furnace inner diameter D is in the range of 0.7 to 2.1.

[0019] The invention according to claim 10 is the high-temperature gas generator according to any one of claims 1 to 9, wherein the fuel gas has a lower heating value of 2000 kcal / Nm 3 A high-temperature gas generating device characterized in that:

[0020] In addition, the invention according to claim 11 is a high-temperature gas generation apparatus according to any one of claims 1 to 10, further comprising a cooling jacket that cools the burner from the outer periphery. Effect of the Invention

[0021] According to the high-temperature gas generating apparatus of the present invention, as described above, the burner forms a flame having a swirling flow and a backflow region (circulating flow) in the vicinity of the central axis of the swirling flow, thereby promoting combustion by circulating the combustion gas and forming a stable flame. In addition, since the flame has the backflow region, the residence time of the fuel gas and the combustion supporting gas in the combustion chamber is extended, so that it is possible to suppress the remaining of unburned fuel gas and the combustion supporting gas. This makes it possible to efficiently and stably generate high-temperature gas and to miniaturize the high-temperature gas generating furnace. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a diagram for explaining the configuration of a high-temperature gas generation apparatus according to a first embodiment of the present invention, and is a cross-sectional view along the axial direction of the high-temperature gas generation apparatus, showing the internal structure of the high-temperature gas generation apparatus and the respective flows of fuel gas, combustion supporting gas, and preheated gas together with the swirling flow of the flame that is formed. [Diagram 2] FIG. 2 is a diagram for explaining the configuration of the high-temperature gas generation apparatus according to the first embodiment of the present invention, and is a cross-sectional view taken along the line AA in FIG. [Figure 3A] FIG. 2 is a diagram for explaining the configuration of a high-temperature gas generation apparatus according to a first embodiment of the present invention, and is a cross-sectional view showing, in an enlarged manner, a swirl vane provided at a fuel gas outlet shown in FIG. [Figure 3B] FIG. 2 is a diagram for explaining the configuration of the high-temperature gas generation apparatus according to the first embodiment of the present invention, and is an enlarged side view showing a swirl vane provided at the fuel gas outlet shown in FIG. [Figure 3C]FIG. 2 is a diagram for explaining the configuration of the high-temperature gas generation apparatus according to the first embodiment of the present invention, and is an enlarged plan view showing a swirl vane provided at the fuel gas outlet shown in FIG. [Figure 4] FIG. 1 is a schematic diagram for explaining the configuration of a high-temperature gas generation apparatus according to a second embodiment of the present invention, and is a cross-sectional view along the axial direction of the high-temperature gas generation apparatus, showing the internal structure of the high-temperature gas generation apparatus and the respective flows of fuel gas, combustion supporting gas, and preheated gas together with the swirling flow of the flame that is formed. [Diagram 5] FIG. 1 is a diagram for explaining the configuration of a high-temperature gas generation apparatus according to a third embodiment of the present invention, and is a cross-sectional view along the axial direction of the high-temperature gas generation apparatus, showing the internal structure of the high-temperature gas generation apparatus and the respective flows of fuel gas, combustion supporting gas, and preheated gas together with the swirling flow of the flame that is formed. [Figure 6] FIG. 1 is a diagram for explaining the configuration of a high-temperature gas generation apparatus according to a fourth embodiment of the present invention, and is a cross-sectional view along the axial direction of the high-temperature gas generation apparatus, showing the internal structure of the high-temperature gas generation apparatus and the respective flows of fuel gas, combustion supporting gas, and preheated gas together with the swirling flow of the flame that is formed. [Figure 7] FIG. 1 is a diagram for explaining an embodiment of a high-temperature gas generation apparatus according to the present invention, and is a graph showing the relationship between the oxygen concentration remaining in the generated high-temperature gas and the ratio [L2 / D] of the distance L2 from one end of the heating chamber to the secondary preheated gas supply port to the furnace inner diameter D. [Figure 8] FIG. 1 is a diagram for explaining an embodiment of a high-temperature gas generation apparatus according to the present invention, and is a graph showing the relationship between the temperature of the inner wall of the heating chamber and the ratio [L2 / D] of the distance L2 from one end of the heating chamber to the secondary preheated gas supply port to the furnace inner diameter D. [Figure 9] FIG. 1 is a diagram for explaining an embodiment of a high-temperature gas generation apparatus according to the present invention, and is a graph showing the relationship between the radial distance from the center of the exhaust port and the temperature of the high-temperature gas in the exhaust port in a cross-sectional distribution when the ratio [L1 / D] of the furnace inner length L1 in the direction along the flame formation direction in the heating chamber to the furnace inner diameter D is 0.8. [Figure 10]FIG. 1 is a diagram for explaining an embodiment of a high-temperature gas generation apparatus according to the present invention, and is a graph showing the relationship between the radial distance from the center of the exhaust port and the temperature of the high-temperature gas in the exhaust port in a cross-sectional distribution when the ratio [L1 / D] of the furnace inner length L1 in the direction along the flame formation direction in the heating chamber to the furnace inner diameter D is 1.0. [Figure 11] FIG. 1 is a diagram for explaining an embodiment of a high-temperature gas generation apparatus according to the present invention, and is a graph showing the relationship between the radial distance from the center of the exhaust port and the temperature of the high-temperature gas in the exhaust port in a cross-sectional distribution when the ratio [L1 / D] of the furnace inner length L1 in the direction along the flame formation direction in the heating chamber to the furnace inner diameter D is 0.3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, a high-temperature gas generator according to an embodiment of the present invention will be described with reference to Figs. 1 to 6. The drawings used in the following description may show characteristic parts in an enlarged scale for the sake of clarity, and the dimensional ratios of each component may not be the same as in reality. In addition, the materials exemplified in the following description are merely examples, and the present invention is not limited to them. The present invention may be modified as appropriate within the scope of the present invention.

[0024] First Embodiment The configuration of the high-temperature gas generation apparatus according to the first embodiment of the present invention will be described in detail below. Fig. 1 is a cross-sectional view showing the internal structure of the high-temperature gas generator 1 of this embodiment, and showing the flows of the fuel gas G1, the combustion supporting gas G2, the primary preheated gas (preheated gas) G41, and the secondary preheated gas (preheated gas) G42 together with the swirling flow of the flame F that is formed. Fig. 2 is a cross-sectional view taken along line AA of the high-temperature gas generator 1 shown in Fig. 1. Fig. 3A is an enlarged cross-sectional view of a swirl vane 18 provided at the fuel gas outlet 12a of the high-temperature gas generator 1 shown in Fig. 1, Fig. 3B is a side view showing an enlarged view of the swirl vane 18, and Fig. 3C is a plan view showing an enlarged view of the swirl vane 18.

[0025] As shown in FIG. 1, the high-temperature gas generator 1 of this embodiment has a combustion chamber 16 in which a flame F is formed by a fuel gas G1 and a combustion supporting gas G2, and is equipped with a burner 10 that generates high-temperature combustion gas G3 by the flame F. The high-temperature gas generating device 1 is also equipped with a high-temperature gas generating furnace 20, which has one end 21 connected to the combustion chamber 16 side of the burner 10 and has a cylindrical shape with an internal heating chamber 23 that communicates with the combustion chamber 16, and which supplies primary preheated gas G41 and secondary preheated gas G42 while forming a flame F in the heating chamber 23, thereby mixing the high-temperature combustion gas G3 with the preheated gas to generate high-temperature gas G5, and discharges the high-temperature gas G5 from an exhaust port 25 located at the other end 22 opposite the combustion chamber 16. In the high-temperature gas generation apparatus 1 of this embodiment, the burner 10 forms a flame F having a swirling flow and a backflow region in the vicinity of the central axis of this swirling flow (see symbol J in Figure 1).

[0026] More specifically, in the high-temperature gas generator 1 of the example described in this embodiment, the combustion chamber 16 of the burner 10 is formed in a bottomed cone shape that opens so that the tip 11 side in the direction in which the flame F is formed expands, and a fuel gas outlet 12a that ejects the fuel gas G1 in a swirling flow along the central axis J of the burner 10 is opened at the bottom 16a of the combustion chamber 16. Furthermore, in the high-temperature gas generator 1, a combustion supporting gas outlet 13a that ejects the combustion supporting gas G2 into the inside of the combustion chamber 16 is opened at one or more positions on the inner surface of the combustion chamber 16, or at multiple positions on the side wall 16b in the example shown in FIG. 1. Then, as shown in FIGS. 1 and 2, the combustion supporting gas G2 is ejected toward the fuel gas G1 in a tangential direction to the swirling flow of the fuel gas G1, thereby forming a backflow region in the vicinity of the central axis J of the swirling flow of the fuel gas G1.

[0027] Moreover, the illustrated high-temperature gas generator 1 further includes a cooling jacket 30 for cooling the burner 10.

[0028] In this specification, the central axis J of the high-temperature gas generating apparatus 1 is explained by giving the same symbol (J) to the central axes of the burner 10 and the high-temperature gas generating furnace 20 that constitute the high-temperature gas generating apparatus 1, as well as the central axes of the swirling flows of each gas.

[0029] The high-temperature gas generation apparatus 1 of this embodiment has the above-mentioned configuration and is an apparatus that generates high-temperature gas G5 of, for example, 200 to 1700°C by directly mixing high-temperature combustion gas G3 and preheated gas in the high-temperature gas generation furnace 20 using a so-called direct combustion method. The high-temperature gas G5 generated by the high-temperature gas generator 1 is used, for example, for forming an atmosphere in the smelting of iron and non-ferrous metals, the ceramic firing process, etc. Specifically, the high-temperature gas G5 is obtained by directly mixing, for example, blast furnace top gas (BFG), coke oven gas (COG), natural gas, hydrogen gas (H2), carbon monoxide gas (CO), reducing gas, and gas mixtures thereof that contain combustible components, or oxygen, oxygen-enriched air, or inert gas with the high-temperature combustion gas G3 generated by the burner 10.

[0030] The high-temperature gas generator 1 of this embodiment can use a combustible gas with a low calorific value as the fuel gas G1. For example, 3 The following fuel gas G1 can be used. Examples of such fuel gas G1 include natural gas and gases that satisfy the conditions of being flammable and insoluble in water as a fuel. The high-temperature gas generation apparatus 1 of this embodiment can efficiently and stably generate high-temperature gas G5 even when a fuel gas with a low calorific value is used.

[0031] Here, the "lower heating value" described in the present invention is the higher heating value measured by a calorimeter minus the value obtained by multiplying the latent heat of condensation of water vapor by the amount of water vapor, and can be calculated, for example, by the following formula [(lower heating value) = (higher heating value) - (latent heat of condensation of water vapor) x (amount of water vapor)] (see paragraph 0087 of the republished patent WO2014 / 148536). The method for measuring the calorific value is specified in JIS K2301:2011 "Fuel gas and natural gas - Analysis and test methods", and for example, it can be calculated using the method specified in "8.2 Method for calculating the calorific value (gas chromatography method)".

[0032] In addition, examples of the combustion supporting gas G2 described in this embodiment, as well as the first combustion supporting gas G21 and the second combustion supporting gas G22 (see FIG. 4, etc.), which will be described in detail later, include oxygen-enriched air or oxygen. Moreover, the primary preheated gas G41 and the secondary preheated gas G42 may be, for example, nitrogen gas (N2).

[0033] The burner 10 comprises a combustion chamber 16 in which a flame F is formed with a fuel gas G1 and a combustion-supporting gas G2, a fuel gas nozzle 12a which opens into the bottom 16a of the combustion chamber 16 and supplies the fuel gas G1 to the combustion chamber 16 via a fuel gas supply passage 12, and a combustion-supporting gas nozzle 13a which opens into a side wall 16b of the combustion chamber 16 and supplies the combustion-supporting gas G2 to the combustion chamber 16 via the combustion-supporting gas supply passage 13.

[0034] In the illustrated example, the combustion chamber 16 is a recess formed in a bottomed cone shape that opens so as to expand in diameter toward the tip 11 side, and has a substantially trapezoidal longitudinal section. As described above, the burner 10 generates a flame F in this combustion chamber 16, thereby generating high-temperature combustion gas G3 toward the downstream side of the burner 10, i.e., toward the high-temperature gas generator 20.

[0035] As described above, the fuel gas outlet 12a and the combustion supporting gas outlet 13a are opened inside the combustion chamber 16, and a flame F is formed inside the combustion chamber 16 by the fuel gas G1 ejected from the fuel gas outlet 12a and the combustion supporting gas G2 ejected from the combustion supporting gas outlet 13a.

[0036] In the illustrated example, the fuel gas supply passage 12 ejects the fuel gas G1 in the axial direction of the burner 10 from a fuel gas outlet 12a that opens at a position outside the central axis J in the bottom 16a of the combustion chamber 16. The fuel gas supply passage 12 is connected to a tank filled with the fuel gas G1 via a fuel flow passage pipe and a fuel control unit (not shown), for example, and ejects the fuel gas G1 from the fuel gas outlet 12a toward the inside of the combustion chamber 16.

[0037] Although detailed illustration is omitted, for example, a plurality of fuel gas nozzles 12a are arranged at equal intervals on a circumference centered on the central axis J in the bottom 16a of the combustion chamber 16 so as to surround the central axis J. As long as the multiple fuel gas outlets 12a are open to the bottom 16a of the combustion chamber 16, the arrangement intervals, number of holes, shape, and the like are not particularly limited and can be set arbitrarily.

[0038] In the illustrated example, the combustion supporting gas supply passage 13 ejects the combustion supporting gas G2 from the combustion supporting gas nozzle 13a opening in the side wall 16b of the combustion chamber 16 so as to be perpendicular to the central axis J of the burner 10. More specifically, as described above, the combustion supporting gas G2 ejected from the combustion supporting gas nozzle 13a is ejected toward the fuel gas G1 ejected from the fuel gas nozzle 12a in a tangential direction to the swirling flow of the fuel gas G1. As a result, the combustion supporting gas G2 ejected from the combustion supporting gas nozzle 13a forms a backflow region in the vicinity of the central axis of the swirling flow of the fuel gas G1, i.e., the central axis J of the burner 10.

[0039] Detailed illustration of the combustion supporting gas nozzles 13a is omitted, but for example, multiple combustion supporting gas nozzles 13a are arranged at equal intervals on a circumference centered on the central axis J on the side wall 16b of the combustion chamber 16, so as to surround the fuel gas nozzle 12a from the outside in a plan view. Furthermore, as long as the plurality of combustion supporting gas outlets 13a are open to the side wall 16b of the combustion chamber 16, there are no particular limitations on the arrangement intervals, number of holes, shape, etc., and these can be set arbitrarily.

[0040] The burner 10 provided in the high-temperature gas generation apparatus 1 of this embodiment has a swirl vane 40 arranged at a fuel gas outlet 12a for ejecting the fuel gas G1 as a swirl flow. Although the detailed structure of the swirl vanes 40 is omitted in Figure 1, as shown in Figures 3A and 3B (see also Figure 1), inside the fuel gas outlet 12a and the fuel gas supply passage 12, the swirl vanes 40 are arranged on the outer peripheral surface of the inner pipe of the fuel gas supply passage 12 so as to be inclined with respect to the central axis of the fuel gas outlet 12a, i.e., the central axis J of the burner 10. Also, the swirl vanes 40 may be fixed to the inner pipe 12b of the fuel gas supply passage 12 without rotating, for example.

[0041] In addition, in the example shown in Figure 3B, four swirl vanes 40 are arranged at equal intervals in the circumferential direction on the outer circumferential surface of the fuel gas supply passage 12, and the radially outermost portions of the swirl vanes 40 abut or are close to the inner surface of the outer pipe of the fuel gas supply passage 12.

[0042] The inclination angle of the swirl vanes 40 with respect to the central axis J is not particularly limited, but from the viewpoint of effectively imparting a swirl flow to the fuel gas G1, it is more preferable that the angle be in the range of, for example, 40 to 60°. Here, the inclination angle of the swirl vane 40 with respect to the central axis J can be calculated from the following formula (1) by determining the outer and inner diameters of the fuel gas supply passage 12 from the flow rate and ejection speed of the fuel gas G1 and setting the swirl number represented by formula (1) described below. For example, when the swirl number is 0.65, the inclination angle of the swirl vane 40 with respect to the central axis J obtained from the following formula (1) is 40°, and when the swirl number is 1.4, the inclination angle of the swirl vane 40 with respect to the central axis J is 60°.

[0043] In the illustrated example, the swirl vanes 40 are provided in four locations, however, the number of swirl vanes 40 to be installed is not particularly limited, and they may be provided in five or more locations within the fuel gas supply passage 12, or a configuration in which they are provided in less than four locations may be adopted. Furthermore, the inclination angle of the swirl vanes 40 with respect to the central axis J and the number of the swirl vanes 40 may be appropriately changed taking into consideration the size of the burner 10 and the strength of the swirl flow.

[0044] The fuel gas G1 supplied from the fuel gas supply passage 12 passes through the swirl vane 40 and is ejected from the fuel gas outlet 12a. At this time, the fuel gas G1 flows along the inclination of the swirl vane 40, and is ejected into the combustion chamber 16 while flowing in a swirling manner around the central axis J of the burner 10. The swirl vane 40 also generates a swirling flow in the same direction as the swirling flow generated by the combustion supporting gas outlet 13a.

[0045] In this embodiment, by providing the fuel gas nozzle 12a with the swirl vanes 40 having the above configuration, it is more preferable that the swirl number, represented by the following formula (1), at the fuel gas nozzle 12a is 0.65 or more.

[0046]

number

[0047] In the above formula (1), S is the swirl number (-), d2 is the inner diameter of the outer tube of the fuel gas nozzle 12a (fuel gas supply passage 12), d5 is the outer diameter of the inner tube of the fuel gas nozzle 12a (fuel gas supply passage 12), and α is the inclination angle (°) of the swirl vane 40 with respect to the central axis J.

[0048] In general, the characteristics of a swirling flow, i.e., the swirling strength, are expressed by the swirl number (S) defined by the above formula (1). The larger the value of this swirl number (S), the stronger the swirling flow. A swirl number of 0.65 or more results in a strong swirling flow (see, for example, paragraphs 0025-0026 of JP 2004-108656 A).

[0049] In the burner 10, the swirl vane 40 having the above-mentioned configuration is disposed at the fuel gas outlet 12a, so that a swirling flow is generated in the fuel gas G1 ejected from the fuel gas outlet 12a. Furthermore, the combustion supporting gas G2 ejected from the combustion supporting gas outlet 13a is ejected toward the fuel gas G1 in a tangential direction to the swirling flow of the fuel gas G1, so that a backflow region is formed near the central axis of the swirling flow. As a result, the flame F formed in the combustion chamber 16 has a swirling flow and also has a backflow region near the central axis of the swirling flow.

[0050] As described above, the high-temperature gas generator 20 supplies primary preheated gas G41 and secondary preheated gas G42 while forming a flame F in the heating chamber 23, thereby mixing the high-temperature combustion gas G3 with the preheated gases G41, G42 to generate high-temperature gas G5, and discharges the high-temperature gas G5 from an exhaust outlet 25 located at the other end 22 opposite the combustion chamber 16.

[0051] As described above, the high-temperature gas generator 20 is configured in a roughly cylindrical shape with one end 21 connected to the tip 11 side, which is the downstream side of the burner 10, and with an internal heating chamber 23 communicating with the combustion chamber 16 of the burner 10. That is, in the heating chamber 23, the flame F formed in the combustion chamber 16 of the burner 10 is formed so as to spread toward the other end 22 side, which is the downstream side.

[0052] Opening inside the heating chamber 23 are a primary preheated gas outlet 26a for supplying a primary preheated gas G41 as a preheated gas, and a secondary preheated gas outlet 27a for supplying a secondary preheated gas G42 as a preheated gas.

[0053] The primary preheated gas outlet 26a is disposed at a position on one end 21 side of the high temperature gas generator 20 where the primary preheated gas G41 is ejected from the outer periphery of the burner 10 toward the inside of the heating chamber 23. That is, the primary preheated gas outlet 26a is configured, for example, in an annular slit shape in a plan view, and uniformly ejects and supplies the primary preheated gas G41 into the inside of the heating chamber 23 via the primary preheated gas supply path 26 configured annularly so as to surround the outside of the burner 10. As described above, the primary preheated gas outlets 26a are arranged so as to open from the periphery of the burner 10 into the heating chamber 23, and the arrangement interval, shape, and the like are not particularly limited and can be set arbitrarily. For example, the primary preheated gas outlets 26a may be configured from a plurality of outlets, and these outlets may be arranged in a ring shape so as to surround the outside of the burner 10.

[0054] The secondary preheated gas outlets 27a are arranged concentrically at at least three locations on the inner surface of the heating chamber 23 at positions for ejecting the secondary preheated gas G42 toward the central axis J of the high-temperature gas generator 20. That is, as shown in Fig. 1, the secondary preheated gas outlets 27a collide the secondary preheated gas G42 with each other near the central axis of the high-temperature gas generator 20, thereby forming an airflow from the burner 10 connected to one end 21 toward the exhaust port 25 arranged at the other end 22. Furthermore, as long as the multiple secondary preheated gas outlets 27a are arranged so that they open at three or more locations on the inner surface of the heating chamber 23, as described above, their arrangement spacing, number of holes, shape, etc. are not particularly limited and can be set arbitrarily.

[0055] As described above, the exhaust outlet 25 discharges the high-temperature gas G5 generated in the heating chamber 23 to the outside, and in the illustrated example, it is connected to the heating chamber 23 and is configured to protrude cylindrically from the inner wall of the furnace toward the outside of the high-temperature gas generator 20.

[0056] With the above configuration, in the high-temperature gas generator 20, the flame F, which has a swirling flow formed by the burner 10 and has a backflow region (circulating flow) near the central axis of the swirling flow, collides with the secondary preheated gas G42, causing stagnation in the flow of the high-temperature combustion gas G3. This lengthens the reaction time between the high-temperature combustion gas G3 and the primary preheated gas G41 and secondary preheated gas G42, promoting combustion, and promoting mixing of the high-temperature combustion gas G3 with the primary preheated gas G41 and secondary preheated gas G42.

[0057] In addition, the secondary preheated gas outlets 27a may be provided at least in three locations on the inner surface of the heating chamber 23, but it is more preferable to provide them at four or more locations in order to provide symmetry to the secondary preheated gas G42 ejected into the heating chamber 23.

[0058] In addition, the material constituting the heating chamber 23 is not particularly limited, and examples thereof include refractories such as high alumina castables. From the viewpoint of extending the service life, however, it is preferable to use a refractory material having a fire-resistant temperature of about 1600°C or higher.

[0059] In addition, the dimensions of the heating chamber 23 are not particularly limited, but for example, as shown in FIG. 1, it is preferable that the ratio [L1 / D] of the furnace inner length L1 in the direction along the formation direction of the flame F to the furnace inner diameter D is in the range of 1 to 3. When the above ratio [L1 / D] is 1 or more, the high-temperature combustion gas G3 and the secondary preheated gas G42 in the heating chamber 23 can be mixed sufficiently, and the high-temperature gas G5 discharged from the exhaust port 25 has a uniform and high temperature. In addition, when the above ratio [L1 / D] is 3 or less, it is possible to prevent the furnace wall of the heating chamber 23 from being melted by the flame F, so that the temperature of the high-temperature gas G5 is stabilized and the life of the high-temperature gas generator 20 can be extended.

[0060] Moreover, it is more preferable that the ratio [L2 / D] of the distance L2 from the one end 21 connected to the burner 10 to the center line of the secondary preheated gas outlet 27a of the heating chamber 23 is in the range of 0.7 to 2.1, to the furnace inner diameter D. When the ratio [L2 / D] is 0.7 or more, the influence of the flow of the secondary preheated gas G42 toward the burner 10 side is suppressed from becoming too large, so that the good combustion state of the burner 10 can be maintained and the residual oxygen concentration can be suppressed low. When the ratio [L2 / D] is 2.1 or less, the mixing of the combustion gas and the secondary preheated gas G42 is sufficiently promoted, so that the furnace temperature and the furnace wall temperature of the heating chamber 23 can be suppressed from becoming too high. For the same reason as above, the ratio of the distance L2 to the inner furnace length L1 is more preferably 0.5 to 0.9.

[0061] The cooling jacket 30 is for cooling the burner 10, and in the illustrated example is configured in a cylindrical shape, with a double-pipe structure that covers, via an annular space, the outside of the flow passage pipe that constitutes the combustion supporting gas supply passage 13. This annular space serves as a cooling water flow passage 30a through which the cooling water W flows, and is configured so that the burner 10 can be cooled by the flow of the cooling water W.

[0062] In the illustrated cooling jacket 30, cooling water W is passed through an inlet 30b, passes through a cooling water passage 30a, and is discharged from an outlet 30c. In the high-temperature gas generator 1 of this embodiment, the cooling water W cools the burner 10 when passing through the cooling water passage 30a. The cooling jacket 30 protects each component of the burner 10 from the high-temperature atmosphere and radiant heat caused by the flame, and also suppresses excessive heating within the combustion chamber 16.

[0063] The actions and effects obtained by the high-temperature gas generation apparatus 1 of this embodiment having the above-mentioned configuration will be described below. According to the high-temperature gas generator 1 of this embodiment, as described above, the burner 10 forms the flame F as a flame with a swirl flow and a backflow region (circulation flow: a flow that flows back to the burner 10 side) in the vicinity of the central axis J of the swirl flow, thereby promoting combustion by circulating the combustion gas and forming a more stable flame F. In addition, since the flame F has the above-mentioned backflow region, the flame F and the secondary preheated gas G42 are unlikely to collide on the central axis J, and the combustion state of the flame F is stabilized, so that the high-temperature combustion gas G3 can be efficiently and stably generated even in a compact high-temperature gas generator 20. Furthermore, since the flame F has the above-mentioned backflow region, the residence time of the combustion gas and the combustion supporting gas G2 in the combustion chamber 16 is extended, making it possible to suppress the remaining of unburned fuel gas and combustion supporting gas. As a result, even if the high-temperature gas generator 20 is compact or a fuel gas G1 with a low calorific value is used, the high-temperature gas G5 can be generated efficiently and stably, and the high-temperature gas generator 20 can be made smaller and have a longer life.

[0064] In addition, by dividing the preheated gas into a primary preheated gas G41 and a secondary preheated gas G42 and ejecting the primary preheated gas G41 from the primary preheated gas ejection port 26a arranged around the burner 10, the primary preheated gas G41 flows between the furnace wall of the heating chamber 23 and the spreading flame F, and the furnace wall can be prevented from becoming hot. In particular, in the case of the burner 10 described in this embodiment, which has a combustion chamber 16 formed as a recessed portion formed in a bottomed cone shape, if a configuration is adopted in which the formed flame F easily spreads in the heating chamber 23 of the high-temperature gas generating furnace 20, the furnace wall temperature can be prevented from rising, and an effect of extending the life can be obtained.

[0065] Moreover, the secondary preheated gas G42 is ejected from the side surface of the heating chamber 23 toward the central axis J and collides with the flame F, forming a flow toward the burner 10 side (reverse flow region) and a flow toward the exhaust port 25 side near the central axis J of the heating chamber 23. Of these, the secondary preheated gas G42 toward the burner 10 side is taken into the high-temperature combustion gas G3 generated by the flame F of the burner 10, and circulates together with this high-temperature combustion gas G3 inside the heating chamber 23, promoting mixing. Also, the secondary preheated gas G42 is taken into the flame F to suppress a temperature rise of the flame F, and a rise in the furnace wall temperature of the heating chamber 23 can be suppressed, so that the high-temperature gas generating furnace 20 made of refractory material can be extended in life without melting.

[0066] In addition, the flame F formed by the burner 10 provided in the high-temperature gas generation apparatus 1 of this embodiment can maintain a stable combustion state because the secondary preheated gas G42 does not obstruct the flow of the flame F.

[0067] Furthermore, in the high-temperature gas generator 1 of this embodiment, when a configuration further including a cooling jacket 30 as in the illustrated example is adopted, the following effects can be obtained. That is, by providing the cooling jacket 30, for example, the burner 10 and the cooling water W come into direct contact with each other, or the burner 10 and the cooling water W come into contact with each other via another structure, so that the burner 10 can be sufficiently cooled and melting damage can be prevented. Also, deformation or damage of the burner 10 or the entire high-temperature gas generator 1 due to thermal stress can be prevented, and fatigue damage caused by repeated application of thermal stress can be minimized, enabling an extended lifespan to be achieved.

[0068] <Second embodiment> Hereinafter, the configuration of a high-temperature gas generation apparatus according to a second embodiment of the present invention will be described in detail with reference to FIG. In the following description of the high-temperature gas generation apparatus 1A of this embodiment, the same components as those of the high-temperature gas generation apparatus 1 of the first embodiment shown in Figures 1, 2, and 3A to 3B will be given the same symbols, and detailed descriptions thereof may be omitted.

[0069] Figure 4 is a cross-sectional view showing the internal structure of the high-temperature gas generation apparatus 1A of this embodiment, and also showing the flows of the fuel gas G1, the first combustion supporting gas (combustion supporting gas) G21, the second combustion supporting gas (combustion supporting gas) G22, the primary preheated gas (preheated gas) G41, and the secondary preheated gas (preheated gas) G42, together with the swirling flow of the flame F that is formed.

[0070] As shown in Figure 4, the high-temperature gas generation apparatus 1A of this embodiment is similar to the high-temperature gas generation apparatus 1 of the first embodiment shown in Figure 1 etc. in that the high-temperature gas generator 20 is configured so that a primary preheated gas outlet 26a for supplying primary preheated gas G41 and a secondary preheated gas outlet 27a for supplying secondary preheated gas G42 are opened inside the heating chamber 23. On the other hand, the high-temperature gas generator 1A of this embodiment is different from the high-temperature gas generator 1 of the first embodiment shown in Fig. 1 etc. in that the burner 10A is composed of a first combustion supporting gas outlet 14a for ejecting a first combustion supporting gas G21 as a combustion supporting gas and a second combustion supporting gas outlet 15a for ejecting a second combustion supporting gas G22 as a combustion supporting gas. Also, the high-temperature gas generator 1A of this embodiment is different from the high-temperature gas generator 1 of the first embodiment in that the first combustion supporting gas outlet 14a opens to the bottom 16a of the combustion chamber 16, and is arranged on the central axis J of the burner 10A so as to be surrounded by the fuel gas outlet 12a in a plan view, and is configured to eject the first combustion supporting gas G21 along the central axis J of the burner 10A. Furthermore, the high-temperature gas generator 1A of this embodiment differs from the high-temperature gas generator 1 of the first embodiment in that the second combustion supporting gas outlet 15a is arranged on the side wall 16b of the combustion chamber 16 and ejects the second combustion supporting gas G22 toward the fuel gas G1 and the first combustion supporting gas G21.

[0071] The high temperature gas generator 1A of this embodiment generates high temperature combustion gas G3 by a flame F formed in the combustion chamber 16 of the burner 10A, similarly to the high temperature gas generator 1 of the first embodiment. The high temperature gas generator 1A generates high temperature gas G5 of, for example, 200 to 1700°C by directly mixing the high temperature combustion gas G3 with the primary preheated gas G41 and the secondary preheated gas G42 in the high temperature gas generator 20 by a direct combustion method.

[0072] The first combustion supporting gas supply passage 14 is arranged coaxially with the fuel gas supply passage 12 on the central axis J of the burner 10A so as to be surrounded by the fuel gas supply passage 12. The first combustion supporting gas supply passage 14 is also provided so as to eject the first combustion supporting gas G21 from a first combustion supporting gas ejection port 14a opening in the bottom 16a of the combustion chamber 16 toward the inside of the combustion chamber 16 in the axial direction of the burner 10A. The first combustion supporting gas outlet 14a is not particularly limited in shape, etc., as long as it opens into the combustion chamber 16, and can be designed arbitrarily.

[0073] In the illustrated example, the second combustion supporting gas supply passage 15 ejects the second combustion supporting gas G22 from the second combustion supporting gas outlet 15a opening in the side wall 16b of the combustion chamber 16 in a direction perpendicular to the central axis J of the burner 10A, similar to the combustion supporting gas supply passage 13 of the burner 10 provided in the high temperature gas generator 1 of the first embodiment. More specifically, the second combustion supporting gas G22 ejected from the second combustion supporting gas outlet 15a ejects toward the fuel gas G1 ejected from the fuel gas outlet 12a in a tangential direction to the swirling flow of the fuel gas G1. As a result, the second combustion supporting gas G22 ejected from the second combustion supporting gas outlet 15a forms a backflow area in the vicinity of the central axis of the swirling flow of the fuel gas G1, i.e., the central axis J of the burner 10A.

[0074] Similar to the combustion supporting gas nozzle 13a described in the first embodiment, the second combustion supporting gas nozzles 15a are arranged at equal intervals in multiple numbers, for example, on a circumference centered on the central axis J in the side wall 16b of the combustion chamber 16, so as to surround the fuel gas nozzle 12a from the outside in a plan view. Furthermore, as long as the second combustion supporting gas ports 15a are open to the side wall 16b of the combustion chamber 16, there are no particular limitations on the arrangement intervals, number of holes, shape, etc., and they can be set arbitrarily.

[0075] Furthermore, in the high-temperature gas generator 1A of this embodiment, as in the high-temperature gas generator 1 of the first embodiment, a swirl vane 40 (Figures 3A to 3C) for ejecting the fuel gas G1 as a swirling flow is arranged at the fuel gas outlet 12a of the burner 10A, and in the illustrated example, is arranged on the pipe surface of the first combustion supporting gas supply passage 14 which is surrounded by the fuel gas supply passage 12.

[0076] The high-temperature gas generation apparatus 1A of this embodiment has the above-mentioned configuration, and similarly to the high-temperature gas generation apparatus 1 of the first embodiment, the burner 10A forms a flame F having a swirling flow and a backflow area near the central axis J of this swirling flow.

[0077] According to the high temperature gas generator 1A of this embodiment, in contrast to the high temperature gas generator 1 of the first embodiment in which the combustion supporting gas G2 is ejected only from the combustion supporting gas nozzle 13a provided in the side wall 16b of the combustion chamber 16 as shown in Fig. 1, a configuration is further adopted in which a first combustion supporting gas G21 is ejected from a first combustion supporting gas nozzle 14a arranged on the central axis J of the burner 10A toward the inside of the combustion chamber 16. As a result, the high temperature gas generator 1A can form a central flame F1 serving as an ignition source as the flame F, so that even when a fuel with a lower calorific value is used as the fuel gas G1, the flame F can be formed with stable combustion.

[0078] More specifically, the high-temperature gas generator 1A of this embodiment is configured to eject the first combustion supporting gas G21 from the central axis J of the burner 10A as described above, and as in the first embodiment, the circulation of the fuel gas G1 promotes combustion and forms a more stable flame F. In addition, since the flame F has a backflow region, the residence time of the fuel gas G1, the first combustion supporting gas G21, and the second combustion supporting gas G22 in the combustion chamber 16 becomes longer, so that it is possible to suppress the remaining of unburned fuel gas and combustion supporting gas. As a result, even if a gas with a low calorific value is used as the fuel gas G1, it is possible to efficiently and stably generate the high-temperature gas G5, and it is possible to reduce the size and extend the life of the high-temperature gas generator 20.

[0079] Although detailed illustration is omitted in Figure 4, the first combustion supporting gas supply passage 14 and the second combustion supporting gas supply passage 15 provided in the burner 10A of the high-temperature gas generating apparatus 1A may be configured to supply the combustion supporting gases (first combustion supporting gas G21 and second combustion supporting gas G22) from the same supply pipe, or may be configured to supply the combustion supporting gases from separate supply sources through different supply pipes.

[0080] <Third embodiment> Hereinafter, the configuration of a high-temperature gas generation apparatus according to a third embodiment of the present invention will be described in detail with reference to FIG. In the description of the high-temperature gas generator 1B of this embodiment given below, the same components as those of the first embodiment of the high-temperature gas generator 1 shown in Figures 1, 2, and 3A-3B, and the high-temperature gas generator 1A of the second embodiment shown in Figure 4 will be given the same symbols, and detailed descriptions thereof may be omitted.

[0081] Figure 5 is a cross-sectional view showing the internal structure of the high-temperature gas generation apparatus 1B of this embodiment, and also showing the flows of the fuel gas G1, the first combustion supporting gas G21, the second combustion supporting gas G22, the primary preheated gas G41, and the secondary preheated gas G42, together with the swirling flow of the flame F that is formed.

[0082] As shown in Figure 5, the high-temperature gas generation apparatus 1B of this embodiment is similar to the high-temperature gas generation apparatus 1A of the second embodiment shown in Figure 4 in that the burner 10A is composed of a first combustion supporting gas nozzle 14a that ejects a first combustion supporting gas G21 as a combustion supporting gas, and a second combustion supporting gas nozzle 15a that ejects a second combustion supporting gas G22 as a combustion supporting gas. On the other hand, the high-temperature gas generation apparatus 1B of this embodiment differs from the high-temperature gas generation apparatus 1A of the second embodiment in that the high-temperature gas generator 20B is provided with a secondary preheated gas supply pipe 29 that covers the outer periphery of the heating chamber 23 from the outside, and is configured to eject secondary preheated gas G42 from the secondary preheated gas outlet 27a into the heating chamber 23 via a secondary preheated gas supply passage 27 that is connected to this secondary preheated gas supply pipe 29.

[0083] Like the high-temperature gas generator 1 of the first embodiment and the high-temperature gas generator 1A of the second embodiment, the high-temperature gas generator 1B of this embodiment generates high-temperature combustion gas G3 by a flame F formed in the combustion chamber 16 of the burner 10A, and generates high-temperature gas G5 by directly mixing the high-temperature combustion gas G3 with the primary preheated gas G41 and the secondary preheated gas G42 in the high-temperature gas generator 20B.

[0084] 5, the secondary preheated gas supply pipe 29 is configured in an annular shape so as to cover the outer periphery of the heating chamber 23 from the outside, and the secondary preheated gas G42 is introduced from a preheated gas inlet 29a. Then, the secondary preheated gas G42 flows from the secondary preheated gas supply pipe 29 into the secondary preheated gas supply path 27, so that the secondary preheated gas G42 is ejected from the secondary preheated gas outlet 27a toward the inside of the heating chamber 23.

[0085] According to the high temperature gas generator 1B of this embodiment, a configuration is adopted in which a high temperature gas generator 20B having a secondary preheated gas supply pipe 29 is further provided so as to cover the outer periphery of the heating chamber 23 from the outside, in addition to the high temperature gas generator 1A of the second embodiment as shown in Fig. 4. As a result, the secondary preheated gas G42 is preheated by the heat dissipated in the heating chamber 23, and by ejecting this secondary preheated gas G42 into the heating chamber 23, it is possible to suppress the heat loss from the furnace body constituting the heating chamber 23 to be extremely small relative to the amount of heat input. Therefore, the high-temperature combustion gas G3 and the primary preheated gas G41 and secondary preheated gas G42 can be mixed more effectively, so that the high-temperature gas G5 can be generated efficiently and stably.

[0086] <Fourth embodiment> Hereinafter, the configuration of a high-temperature gas generation apparatus according to a fourth embodiment of the present invention will be described in detail with reference to FIG. In the description of the high-temperature gas generator 1C of this embodiment given below, the same components as those of the first embodiment of the high-temperature gas generator 1 shown in Figures 1, 2 and 3A-3B, the second embodiment of the high-temperature gas generator 1A shown in Figure 4, and the third embodiment of the high-temperature gas generator 1B shown in Figure 5 will be given the same symbols, and detailed descriptions thereof may be omitted.

[0087] Figure 6 is a cross-sectional view showing the internal structure of the high-temperature gas generation apparatus 1C of this embodiment, and also showing the flows of the fuel gas G1, the first combustion supporting gas G21, the second combustion supporting gas G22, the primary preheated gas G41, and the secondary preheated gas G42, together with the swirling flow of the flame F that is formed.

[0088] As shown in Fig. 6, the high-temperature gas generator 1C of this embodiment is similar to the high-temperature gas generator 1B of the third embodiment shown in Fig. 5 in that the burner 10A is composed of a first combustion supporting gas outlet 14a that ejects a first combustion supporting gas G21 as a combustion supporting gas, and a second combustion supporting gas outlet 15a that ejects a second combustion supporting gas G22 as a combustion supporting gas. In addition, the high-temperature gas generator 1C of this embodiment is similar in configuration to the high-temperature gas generator 1B of the third embodiment in that the high-temperature gas generator 20C is equipped with a secondary preheated gas supply pipe 29C that covers the outer periphery of the region on the other end 22 side of the heating chamber 23 from the outside, and the secondary preheated gas G42 is ejected from the secondary preheated gas outlet 27a toward the inside of the heating chamber 23 through the secondary preheated gas supply path 27 that communicates with the secondary preheated gas supply pipe 29C.

[0089] On the other hand, the high temperature gas generator 1C of this embodiment further includes a primary preheated gas supply pipe 28 that covers the outer periphery of the region on one end 21 side of the heating chamber 23 from the outside so that the high temperature gas generator 20C is adjacent to the secondary preheated gas supply pipe 29C. Also, a primary preheated gas supply passage 26 arranged at a position on one end 21 side of the high temperature gas generator 20C where the primary preheated gas G41 is ejected from the outer periphery side of the burner 10A toward the inside of the heating chamber 23 is connected to the primary preheated gas supply pipe 28. The high temperature gas generator 1C of this embodiment differs from the high temperature gas generator 1B of the third embodiment in that the secondary preheated gas G42 can be ejected from the primary preheated gas ejection port 26a toward the inside of the heating chamber 23 via the primary preheated gas supply passage 26.

[0090] Like the high-temperature gas generator 1 of the first embodiment, the high-temperature gas generator 1A of the second embodiment, and the high-temperature gas generator 1B of the third embodiment, the high-temperature gas generator 1C of this embodiment generates high-temperature combustion gas G3 by a flame F formed in the combustion chamber 16 of the burner 10A, and generates high-temperature gas G5 by directly mixing the high-temperature combustion gas G3 with the primary preheated gas G41 and the secondary preheated gas G42 in the high-temperature gas generator 20B.

[0091] 6, the primary preheated gas supply pipe 28 is configured in an annular shape so as to cover from the outside the region on one end 21 side on the outer periphery of the heating chamber 23, and the primary preheated gas G41 is introduced from the preheated gas inlet 28a. Then, the primary preheated gas G41 flows from the primary preheated gas supply pipe 28 into the primary preheated gas supply path 26, so that the primary preheated gas G41 is ejected from the primary preheated gas ejection port 26a toward the inside of the heating chamber 23.

[0092] 6, the secondary preheated gas supply pipe 29C is configured in an annular shape so as to cover the area on the other end 22 side on the outer periphery of the heating chamber 23 from the outside, and is disposed close to the above-mentioned primary preheated gas supply pipe 28 on the outer periphery of the heating chamber 23. Similarly to the high-temperature gas generator 1B of the second embodiment, the secondary preheated gas G42 is introduced into the secondary preheated gas supply pipe 29C in the illustrated example from a preheated gas inlet 29a. The secondary preheated gas G42 flows from the secondary preheated gas supply pipe 29C into the secondary preheated gas supply path 27, so that the secondary preheated gas G42 is ejected from the secondary preheated gas outlet 27a toward the inside of the heating chamber 23.

[0093] According to the high-temperature gas generator 1C of this embodiment, a configuration is adopted in which a high-temperature gas generator 20C having a primary preheated gas supply pipe 28 is further provided to cover the region on one end 21 side on the outer periphery of the heating chamber 23 from the outside, in addition to the high-temperature gas generator 1B of the third embodiment as shown in FIG. 5. As a result, not only the secondary preheated gas 42 but also the primary preheated gas G41 is preheated by the heat dissipated in the heating chamber 23. Then, by ejecting the primary preheated gas 41 and the secondary preheated gas 42 into the heating chamber 23, it is possible to suppress the heat loss from the furnace body constituting the heating chamber 23 to be extremely small relative to the input heat amount, as described above. Furthermore, the primary preheated gas 41 is preheated by the primary preheated gas supply pipe 28, which has the effect of improving the stability of the flame F formed to spread in the heating chamber 23. Therefore, as described above, the high-temperature combustion gas G3 and the primary preheated gas G41 and secondary preheated gas G42 can be mixed more effectively, making it possible to generate the high-temperature gas G5 efficiently and stably.

[0094] <Action and effect> As described above, according to the high-temperature gas generator 1 (1A, 1B, 1C) of the present embodiment, the burner 10 (10A) forms the flame F to have a swirling flow and a backflow region (circulation flow) in the vicinity of the central axis J of the swirling flow, thereby promoting combustion by circulating the combustion gas and forming a stable flame F. In addition, since the flame F has the above-mentioned backflow region, the residence time of the fuel gas G1 and the combustion supporting gas G2 (G21, G22) in the combustion chamber 16 becomes longer, so that it is possible to suppress the unburned fuel gas G1 and the combustion supporting gas G2 (G21, G22) from remaining. As a result, even when a fuel gas G1 with a low calorific value is used, the high-temperature gas G5 can be efficiently and stably generated, and the high-temperature gas generator 20 (20A, 20B) can be made smaller and have a longer life.

[0095] <Other aspects of the present invention> Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments described above, and various modifications and variations are possible within the scope of the gist of the present invention as described in the claims. EXAMPLES

[0096] The high-temperature gas generating apparatus according to the present invention will be described in more detail below with reference to examples, but the present invention is not limited to these. Moreover, the conditions employed in this embodiment are merely examples and, similar to the above, do not limit the present invention.

[0097] <Example 1> In Example 1, a high-temperature gas generating apparatus 1 having the configuration according to the present invention as shown in FIG. 1 was used, and a test was conducted to generate high-temperature gas G5 under conditions using fuel gas G1 having a wide range of low heating value as shown in Tables 1 and 2 below.

[0098] That is, in this embodiment, the high-temperature gas generator 1 has a combustion chamber 16 in which a flame F is formed by a fuel gas G1 and a combustion-supporting gas G2, and is equipped with a burner 10 that generates high-temperature combustion gas G3 by the flame F. The high-temperature gas generator 1 has one end 21 connected to the combustion chamber 16 side of the burner 10, and is cylindrical in shape with a heating chamber 23 inside that communicates with the combustion chamber 16. The high-temperature gas generator 20 is equipped with a high-temperature gas generator 20 that mixes the high-temperature combustion gas G3 and the preheated gas to generate high-temperature gas G5 by supplying a primary preheated gas 31 and a secondary preheated gas 32 while forming a flame F in the heating chamber 23, and discharges the high-temperature gas G5 from an outlet 25 arranged at the other end 22 opposite the combustion chamber 16. The high-temperature gas generator 1 used in this embodiment has a burner 10 that forms a flame F so that the burner 10 has a swirling flow and has a backflow area in the vicinity of the central axis J of the swirling flow.

[0099] In addition, the high-temperature gas generation apparatus 1 used in this embodiment has a ratio [L1 / D] of the furnace inner length L1 in the direction along the flame formation direction of the heating chamber 23 in the high-temperature gas generation furnace 20 to the furnace inner diameter D of 1.4, and a ratio [L2 / D] of the distance L2 from the one end 21 connected to the burner 10 to the secondary preheated gas outlet 27a to the furnace inner diameter D of 1.0.

[0100] The tests were carried out using a "natural gas + H2 + N2 mixed gas" or "natural gas" as the fuel gas G1, as shown in Table 1 below, under conditions using the fuel gas G1 with a wide range of low heating value. In this embodiment, the conditions were set so that the swirl number at the fuel gas nozzle 12a of the burner 10 was 0.65. In addition, tests were conducted by setting the flow rates of the fuel gas G1, the oxidizer (O2) used as the combustion supporting gas G2, and the nitrogen gas (N2) used as the primary preheated gas 41 and the secondary preheated gas 42 under the conditions shown in Table 1 below.

[0101] [Table 1]

[0102] Table 2 below shows a list of the temperature of the high-temperature gas G5 discharged from the exhaust port 25 of the high-temperature gas generator 20, the temperature inside the heating chamber 23, and the residual oxygen concentration in the high-temperature gas G5.

[0103] [Table 2]

[0104] From the results shown in Table 2, it was confirmed that by generating high-temperature gas G5 using the high-temperature gas generation apparatus 1A (see Figure 1) of the present invention, high-temperature gas G5 of 800°C or higher can be stably obtained under all conditions (conditions 1 to 3), and the residual oxygen concentration can be suppressed to an extremely low level. In addition, in a process in which high-temperature gas G5 is used, it is preferable that the residual oxygen concentration be suppressed as low as possible in order to prevent oxidation of raw materials such as iron and non-ferrous raw materials and the resulting products, and to maintain the blast furnace in the process at a high temperature.

[0105] <Example 2> In Example 2, a test was also conducted to generate high-temperature gas G5 using a high-temperature gas generation apparatus 1 having the configuration according to the present invention as shown in FIG. 1 under conditions of using a fuel gas G1 having a wide range of low heating value as shown in Tables 1 and 2 above. In this embodiment, the furnace inner diameter D, furnace inner length L1, and distance L2 from one end 21 to the secondary preheated gas outlet 27a in the high-temperature gas generation apparatus 1 were appropriately changed and tests were conducted to study the reduction of the residual oxygen concentration and unburned gas in the high-temperature gas G5 discharged from the exhaust port 25.

[0106] In general, when reducing gases containing hydrogen (H2) or carbon monoxide (CO) are preheated and supplied to a melting furnace or heat treatment device, if the residual oxygen concentration is too high, it may have adverse effects such as oxidizing raw materials such as iron and non-ferrous metals and products obtained from them. In addition, when oxygen or oxygen-enriched air is preheated and supplied to a burner, residual unburned gas may generate heat inside the burner, which may damage the burner. Furthermore, when an inert gas used as an atmospheric gas in various processes is preheated, the presence of residual oxygen or unburned gas may have adverse effects on the obtained product. In this embodiment, the following study was carried out to determine the optimum conditions for solving the above problems.

[0107] First, in this embodiment, tests were conducted while appropriately changing the ratio [L2 / D] of the distance L2 from the one end 21 to the secondary preheated gas outlet 27a to the furnace inner diameter D within the range of 0.5 to 3, and the optimal value of the above ratio [L2 / D] was investigated. The graph in FIG. 7 shows the relationship between the above ratio [L2 / D] and the oxygen concentration remaining in the generated high-temperature gas. Moreover, the graph in FIG. 8 shows the relationship of the temperature of the inner wall of the heating chamber 23 to the above ratio [L2 / D]. In this test, the temperature of the inner wall of the heating chamber 23 was measured using a thermocouple.

[0108] As shown in FIG. 7, when the above ratio [L2 / D] is smaller than 0.7, the influence of the flow of the secondary preheated gas 42 toward the burner 10 becomes large, the combustion condition of the burner 10 becomes unfavorable, and the residual oxygen concentration tends to become high. On the other hand, as shown in FIG. 8, when the above ratio [L2 / D] is greater than 1.5, the temperature inside the heating chamber 23 increases as the mixing efficiency of the high-temperature combustion gas G3 and the secondary preheated gas 42 gradually decreases, and when the above ratio [L2 / D] is 2.1 or more, the temperature of the furnace wall tends to rise rapidly. The present invention does not particularly limit the above ratio [L2 / D]. However, from the above results, it has been confirmed that it is more preferable to set the above ratio [L2 / D] in the range of 0.7 to 2.1, from the viewpoint of obtaining the effect of reducing the residual oxygen concentration to prevent the raw materials and products from being oxidized, and suppressing the amount of remaining unburned gas to prevent damage to the burner and furnace walls.

[0109] Next, in this embodiment, tests were conducted while appropriately changing the ratio [L1 / D] of the furnace inner length L1 to the furnace inner diameter D in the range of 0.9 to 3.5, the temperature distribution at the exhaust outlet 25 of the high-temperature gas generator 20 was measured, and the optimal value of the above ratio [L1 / D] was investigated. The graph in FIG. 9 shows the relationship between the radial distance from the center of the exhaust port 25 and the temperature of the high-temperature gas G5 inside the exhaust port 25, in terms of cross-sectional distribution, when the above ratio [L1 / D] is set to 0.8. In addition, the graph in Figure 10 shows the cross-sectional distribution of the relationship between the radial distance from the center of the exhaust port 25 and the temperature of the high-temperature gas G5 inside the exhaust port 25 when the above ratio [L1 / D] is 1.3. Furthermore, the graph in Figure 11 shows the cross-sectional distribution of the relationship between the radial distance from the center of the exhaust port 25 and the temperature of the high-temperature gas G5 inside the exhaust port 25 when the above ratio [L1 / D] is 0.3. The above-mentioned cross-sectional distribution means the temperature distribution in the radial direction from the center of the exhaust port 25. In addition, in this test, the temperature of the high-temperature gas G5 was measured using a thermocouple.

[0110] As shown in Figure 9, when the above ratio [L1 / D] is smaller than 1, the high-temperature combustion gas G3 and the secondary preheated gas 42 are not sufficiently mixed in the heating chamber 23, and the temperature of the high-temperature gas G5 near the center at the exhaust port 25 tends to be lower. Furthermore, as shown in FIG. 10, when the ratio [L1 / D] was greater than 3, the temperature of the high-temperature gas G5 tended to gradually decrease due to the effect of heat loss to the furnace body constituting the heating chamber 23. Although the present invention does not particularly limit the above ratio [L1 / D], it has been confirmed from the above results that, from the viewpoint of sufficiently mixing the high-temperature combustion gas G3 and the secondary preheated gas 42 and obtaining the effect of increasing the temperature of the high-temperature gas G5, it is more preferable to set the above ratio [L1 / D] in the range of 1 to 3. [Industrial Applicability]

[0111] The high-temperature gas generator of the present invention can generate high-temperature gas efficiently and stably, and can also reduce the size of a high-temperature gas generating furnace. Therefore, the high-temperature gas generator of the present invention is suitable for heating the inside of various industrial furnaces used in, for example, smelting iron and non-ferrous metals, and ceramic firing processes. [Explanation of symbols]

[0112] 1, 1A, 1B, 1C...High temperature gas generator 10…Burner 11...Tip 12...Fuel gas supply line 12a…Fuel gas outlet 12b…Inner tube 13...Combustion-supporting gas supply line 13a…Combustion-supporting gas outlet 14...First combustion supporting gas supply passage 14a…First combustion supporting gas outlet 15...Second combustion supporting gas supply passage 15a…Second combustion supporting gas outlet 16…Combustion chamber 16a...bottom 16b…Side wall 30…Cooling jacket 30a...Cooling water flow path 30b…Entrance 30c…exit 40...Swirl vane 20...High-temperature gas generator 21...one end 22...other end 23…Heating chamber 25…Discharge port 26...Primary preheated gas supply line 26a…Primary preheated gas supply port 27...Secondary preheated gas supply line 27a…Secondary preheated gas supply port 28...Primary preheated gas supply pipe 28a…Preheated gas inlet 29, 29C…Secondary preheated gas supply pipe 29a…Preheated gas inlet J…Center axis W…Cooling water G1…Fuel gas G2: Combustion-supporting gas G21…First combustion supporting gas (combustion supporting gas) G22: Secondary combustion supporting gas (combustion supporting gas) G3: High-temperature combustion gas G41…Primary preheated gas (preheated gas) G42…Secondary preheated gas (preheated gas) G5…Hot gas F...Flame F1…center flame

Claims

1. a burner having a combustion chamber in which a flame is formed by a fuel gas and a combustion supporting gas, and generating high-temperature combustion gas by the flame; a high-temperature gas generating furnace, one end of which is connected to the combustion chamber side of the burner and which has a cylindrical shape having an internal heating chamber communicating with the combustion chamber, which supplies a preheated gas while forming the flame in the heating chamber, thereby mixing the high-temperature combustion gas with the preheated gas to generate high-temperature gas, and which discharges the high-temperature gas from an exhaust port disposed at the other end opposite the combustion chamber; A high-temperature gas generating apparatus, characterized in that the burner forms the flame so as to have a swirling flow and a backflow region in the vicinity of a central axis of the swirling flow.

2. The burner has a combustion chamber having a bottomed conical shape that opens so that a tip side in a direction in which the flame is formed expands in diameter, A fuel gas outlet that ejects the fuel gas in a swirling flow along a central axis of the burner is opened at a bottom of the combustion chamber, Furthermore, a combustion supporting gas outlet for injecting the combustion supporting gas into the combustion chamber is opened at one or more positions on the inner surface of the combustion chamber, 2. The high-temperature gas generating apparatus according to claim 1, wherein the combustion supporting gas is ejected toward the fuel gas in a tangential direction to the swirling flow of the fuel gas, thereby forming a backflow area near the central axis of the swirling flow of the fuel gas.

3. 3. The high-temperature gas generating apparatus according to claim 2, wherein a swirl vane for ejecting the fuel gas as the swirling flow is disposed at the fuel gas ejection port.

4. 4. The high-temperature gas generating apparatus according to claim 3, wherein the swirl vane has a plurality of vane portions disposed at the fuel gas outlet so as to be inclined with respect to a central axis of the fuel gas outlet.

5. 5. The high-temperature gas generating apparatus according to claim 2, wherein the burner has a swirl number at the fuel gas outlet of 0.65 or more.

6. The burner includes a first combustion supporting gas outlet for ejecting a first combustion supporting gas as the combustion supporting gas, and a second combustion supporting gas outlet for ejecting a second combustion supporting gas as the combustion supporting gas, The first combustion supporting gas outlet is opened to a bottom of the combustion chamber and is disposed on a central axis of the burner so as to be surrounded by the fuel gas outlet in a plan view, and the first combustion supporting gas is injected along the central axis of the burner. A high-temperature gas generating device as described in any one of claims 2 to 5, characterized in that the second combustion-supporting gas outlet is arranged on a side wall of the combustion chamber and ejects the second combustion-supporting gas toward the fuel gas and the first combustion-supporting gas.

7. a primary preheated gas supply port for supplying a primary preheated gas as the preheated gas and a secondary preheated gas supply port for supplying a secondary preheated gas as the preheated gas are open inside the heating chamber; the primary preheated gas supply port is disposed at a position on one end side of the high-temperature gas generating furnace where the primary preheated gas is ejected from an outer periphery side of the burner toward the inside of the heating chamber, the secondary preheated gas supply ports are arranged on the same cross section at at least three locations on the inner surface of the heating chamber at positions for ejecting the secondary preheated gas toward the central axis of the high temperature gas generating furnace, A high-temperature gas generating apparatus as described in any one of claims 1 to 6, characterized in that the secondary preheated gases are collided with each other near the central axis of the high-temperature gas generating furnace, thereby forming an airflow toward the burner connected to the one end and an airflow toward the exhaust port located at the other end.

8. The high-temperature gas generating apparatus according to claim 7, characterized in that the ratio [L1 / D] of the furnace inner length L1 in the direction along the flame formation direction to the furnace inner diameter D is in the range of 1 to 3.

9. The high-temperature gas generating apparatus according to claim 8, characterized in that the ratio [L2 / D] of the distance L2 from the one end connected to the burner to the secondary preheated gas supply port and the furnace inner diameter D is in the range of 0.7 to 2.

1.

10. The fuel gas has a lower heating value of 2000 kcal / Nm ３ The high-temperature gas generating apparatus according to any one of claims 1 to 9, characterized in that:

11. The high-temperature gas generating apparatus according to any one of claims 1 to 10, further comprising a cooling jacket for cooling the burner from an outer periphery side.

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