JP6220543B2 - Burner device and combustion furnace - Google Patents

Description

  The present application relates to a burner device and a combustion furnace for burning fuel, and in particular, powdery biomass, such as sawdust, waste bacteria bed, coffee cake, and other food residues, can be conveyed by air or the like. The present invention relates to a burner apparatus and a combustion furnace capable of burning small-sized fuels satisfactorily.

  Conventionally, in the case of combustion of biomass, solid biomass such as chips and pellets was mainly burned, and powdered biomass was labored such as molding into pellets. . Conventional combustion furnaces have been developed for such solid fuels, and even if powdered biomass is directly put into the combustion chamber, it is difficult to burn it uniformly and satisfactorily. On the other hand, large-scale pulverized coal boilers have been put to practical use as powder combustion technology. Recently, mixed shochu technology in which several percent of powdery woody biomass is mixed with pulverized coal has been implemented. No single combustion of biomass has been implemented. One reason for this is that the combustion characteristics of biomass and fossil fuel are greatly different, such as the theoretical combustion air volume is about half that of fossil fuels such as coal. It was difficult to apply pulverized coal combustion technology.

  In order to respond to the recent needs for expanding the use of renewable energy, a technology capable of efficiently using and burning biomass regardless of the shape such as solid or powder is required. Patent Documents 1 and 2 develop and propose an apparatus for directly combusting powdery biomass. However, all of these require a combustion chamber for flame holding separately from the ignition burner in order to uniformly diffuse and burn the powdery biomass, and the structure is complicated. In addition, since the structure of the combustion furnace for solid fuel and the combustion chamber are different, two combustion chambers are required for each fuel shape in order to add the combustion function of powdered biomass to the combustion furnace for solid fuel. It ’s not practical. Here, the “combustion chamber” refers to a place or space where fuel is burned, or a structure (wall, container, etc.) that forms such a place or space. Furthermore, in the former, it is necessary to always use an ignition burner with fossil fuel. The reason why Patent Documents 1 and 2 have such drawbacks will be described with reference to FIGS.

  FIG. 1 shows the relationship between the air / solid ratio of biomass and coal. The horizontal axis of FIG. 1 is the air ratio (λ: the ratio of the actually supplied combustion air amount to the theoretical air amount necessary for complete combustion). When λ <1, air shortage, λ> 1 When the air is excessive, in general combustion, λ = 1.2 to 3.0. The vertical axis in FIG. 1 is the solid-gas ratio (ratio of combustion air supply mass to fuel mass).

B1 to B3 in FIG. 1 are correlations between the air ratio and the solid-gas ratio for biomass having different moisture contents and carbon (C) contents. Biomass is generally represented by C _n H ₂ 0 _m based on hydrogen, with n = 1 to 1.5 and m = 0.5 to 1.0. The water content and carbon content of B1 to B3 are as follows. Note that m = 0.9.
B1: Water content = 0%, n = 1.5
B2: Water content = 0%, n = 1.0 or water content = 15%, n = 1.5
B 3 : Water content = 15%, n = 1.0

  C1 and C2 in FIG. 1 are examples of coal that can be used as a reference in technologies such as pulverized coal combustion burners, and show examples of anthracite (C1) and steam coal (C2) that are commonly used as typical fuels. ing.

  The air transportability of pulverized fuel is largely determined by the solid-gas ratio. Normally, as shown in FIG. 1, smooth air transport is difficult at a solid-gas ratio of 2.5 or less (powder-air transport unacceptable range), and a solid-gas ratio of 2.5 to 5 is the limit for air transport. (Powder / air transportable limit) It is desirable that the solid-gas ratio is 5 or more for stable transport (powder / air transport stable range).

  The range of the air ratio suitable for ignition (combustion start) and flame holding (combustion maintenance) is referred to as “ignition flame holding range” in the present application. In solid fuels such as coal and biomass, the most suitable air ratio for ignition and flame holding is about 0.5 to 0.8. Since the properties of biomass are diverse, it is desirable that the performance of the burner device can be ignited and flame-held in the range of 0.2 to 1.0.

  FIG. 2 shows the relationship between the air ratio in biomass and the theoretical adiabatic temperature (theoretical combustion temperature). As described above, the ignition flame holding range of biomass is generally about 0.5 to 0.8, and in this range, the theoretical adiabatic temperature is 1000 to 1800 ° C. The air ratio of combustion after ignition (main combustion) is normally 1.5 or more.

  As shown in the hatching in FIG. 1, in the case of coal, the ignition flame holding range and the powder / air transport stable range overlap, so that the function as a powder burner device is fully achieved (ignition is performed directly on the powder conveyed by air). Can hold the flame), but the biomass does not overlap. This is the cause of the drawbacks described above with respect to Patent Documents 1 and 2.

  That is, in Patent Document 1, since it is difficult to uniformly stir and burn fuel in the combustion chamber by the swirling flow of combustion air, it is necessary to always use an ignition burner using fossil fuel.

  In Patent Document 2, in order to promote stirring of the fuel and the combustion air and extend the residence time of the fuel in the combustion chamber, the swirling of the fuel and the combustion air in the combustion chamber S is devised, and the combustion chamber S is preheated. Although self-ignition of fuel is performed, the structure is complicated, and in order to continue combustion, it is necessary to heat the entire combustion chamber S with an ignition burner until the temperature reaches a temperature at which continuous combustion is possible or higher. There is. Patent Document 2 is an invention related to the structure of the combustion chamber S or how to burn in the combustion chamber S, and is not an invention related to the burner device (nozzle 9 of the cited document 2), and is therefore a technical field. Is different.

  Patent Document 3 discloses a gasification facility that generates fuel gas by gasifying biomass by a steam reforming reaction. The combustion furnace (hot gas generation furnace 103) of this gasification facility burns solid fuel to generate high-temperature combustion gas necessary for gasification, but not only solid fuel but also pulverized fuel is used. If possible, the range of use and usefulness will be further enhanced.

JP 2004-132567 A JP 2010-185631 A JP 2009-001826 A

As a burner device using powder as a fuel, for example, there is a coal burner device that is practically used in a pulverized coal boiler for power generation or the like, but it is difficult to use this for a powdery fuel such as biomass. This is because, when a pulverized fuel such as biomass is used in a coal burner device, it is difficult to obtain ignition and flame holding stability, which are essential conditions for the burner device, due to the difference in fuel properties. In addition, pulverized coal boilers for power generation, etc. are equipped with multiple coal burner devices of 10 ⁷ to 10 ⁸ kcal / h, and respond to load changes by changing the number of coal burner devices used, biomass that stuff distribution and if the availability cost points so-called small-scale decentralized equipment is large and that corresponding to the load change in power generation pulverized coal boiler and a similar method is not realistic, 10 ⁴ to 10 It is required that one burner device having a capacity of about ⁶ kcal / h can cope with a wide load range.

In the present application, a burner apparatus and a combustion furnace capable of using powdery biomass as fuel are disclosed. The burner device and the combustion furnace of the present application aim to obtain one or more of the following characteristics.
1) Stable ignition and / or flame holding,
2) The required amount of combustion (heat generation per hour) can be obtained,
3) Combustion is stably maintained and unburned component generation is suppressed,
4) The required combustion gas temperature can be obtained,
5) Capable of responding to a required load change, that is, a change in combustion amount, specifically capable of responding to at least a half load or less,
6) A burner device that can be added to or changed from the solid fuel combustion furnace.

  In the present application, the flow of fuel and air when the fuel is flowing by the air flow (the fuel is dispersed in the air) is referred to as “fuel / air mixed phase flow” or “multiphase flow”. When a part with relatively high fuel concentration and a part with low fuel concentration are formed in the multiphase flow, the part with high fuel concentration is called “high concentration multiphase flow”, and the part with low fuel concentration is called “low concentration multiphase flow”. Call it.

  In the present application, “combustion chamber” refers to a place or space where fuel is burned, or a structure (wall, container, etc.) that forms such a place or space. "Burner device" refers to a device that mixes fuel and air to burn the fuel and / or a device that supplies fuel and air so that ignition and flame holding can be performed. “Mixing chamber” refers to a place or space for mixing fuel and air (or allowing fuel to flow by an air stream) or a structure (wall, container, etc.) that forms such a place or space. “Combustion furnace” means the entire combustion facility including the burner device. A “combustion furnace” may include a combustion chamber.

In the present application, the following inventions are disclosed.
<Claim 1>
A mixing chamber surrounded by a peripheral wall;
A fuel supply port for supplying fuel to the mixing chamber;
An air supply port for supplying primary air to the mixing chamber;
An outlet for discharging the fuel mixed in the mixing chamber and primary air;
A flame-holding plate disposed near the peripheral wall of the discharge port;
A burner device comprising:
The mixing chamber is a vertical mixing chamber in which fuel is dropped and supplied to the mixing chamber by its own weight from the fuel supply port,
The burner device, wherein the air supply port supplies the primary air toward a tangential direction of the mixing chamber so that fuel and primary air swirl in the mixing chamber.
<Claim 2>
An ignition flame holding region having an air ratio of 0.2 to 1 near the flame holding plate or downstream thereof is further provided with secondary air supply means for supplying secondary air in the vicinity of the flame holding plate or downstream thereof. The burner device according to claim 1, wherein: is formed.
<Claim 3>
The burner apparatus according to claim 1 or 2, further comprising tertiary air supply means for supplying tertiary air.
<Claim 4>
The burner device according to any one of claims 1 to 3, wherein the fuel is a pulverized fuel.
<Claim 5>
The burner device according to any one of claims 1 to 4,
A combustion furnace having a combustion chamber disposed downstream of the discharge port.
In the present application, the following inventions are further disclosed.

(1) a mixing chamber;
A fuel / air supply for supplying fuel and air to the mixing chamber such that a low concentration multiphase flow having a low fuel concentration and a high concentration multiphase flow having a higher fuel concentration than the low concentration multiphase flow are formed in the mixing chamber. Means,
An outlet for releasing the fuel and air in the mixing chamber;
A burner device comprising a flame holding plate arranged at a position on the flow path of the high-concentration multiphase flow at the discharge port.

  (2) The burner device according to (1), further comprising secondary air supply means for supplying secondary air to the vicinity of the flame holding plate or downstream thereof.

  (3) The burner device according to (1) or (2), further comprising a second flame holding plate on the downstream side of the flame holding plate.

  (4) The burner device according to any one of (1) to (3), wherein the flame holding plate has a heat insulating structure.

  (5) The burner device according to any one of (1) to (4), wherein an ignition flame holding region having an air ratio of 0.2 to 1 is formed in the vicinity of the flame holding plate or downstream thereof.

  (6) The burner device according to (5), wherein a combustion zone having an air ratio of 1.5 or more is formed downstream of the ignition flame holding zone.

  (7) The burner device according to any one of (1) to (6), wherein the fuel is a powder having a particle size of 3 mm or less.

(8) a mixing chamber surrounded by a peripheral wall;
Fuel / air supply means for supplying the fuel and air to the mixing chamber such that a mixed phase flow of fuel and air swirls in the mixing chamber;
An outlet for releasing the fuel and air in the mixing chamber;
A burner device comprising a flame holding plate disposed in the vicinity of the peripheral wall of the discharge port.

(9) any one of the burner devices of (1) to (8);
A combustion furnace having a combustion chamber disposed downstream of the discharge port.

(10) an ignition burner for igniting the fuel;
Temperature measuring means for measuring the temperature in the furnace;
The combustion furnace according to (9), further comprising ignition burner control means for extinguishing the ignition burner when the temperature in the furnace becomes equal to or higher than a predetermined determination temperature.

  In the invention of (1), since a high-concentration multiphase flow is formed in the mixing chamber and is discharged from the discharge port, an ignition flame holding region having an air ratio suitable for ignition and flame holding is provided near or downstream of the discharge port. Can be formed. In addition, since the flame holding plate is provided at a position on the flow path of the high-concentration mixed phase flow at the discharge port, ignition and flame holding can be performed more stably and / or easily. In the invention of (1), the high-concentration multiphase flow is burned at a high temperature with the flame-holding plate, whereby the combustion efficiency can be improved and / or combustion with little unburned content can be achieved.

  In the invention of (2), by having the second air supply means, the adjustment of the air ratio in the vicinity of the flame holding plate or the downstream side thereof becomes easy, and / or the formation of the ignition flame holding area becomes easy. And / or stable ignition and flame holding in a wider load range are possible.

  In the invention of (3), it is possible to perform ignition and flame holding on the second flame holding plate, and stable ignition and flame holding in a wider load range are possible.

  In the invention of (4), it is possible to prevent the flame holding plate from being cooled, and it is possible to further improve the stability of ignition and flame holding.

  In the invention of (5), stable ignition and flame holding on the flame holding plate can be achieved by forming an ignition flame holding region of 0.2 to 1.

  In the invention of (6), complete combustion of the fuel (theoretical adiabatic temperature 1500 ° C.) is possible by forming a combustion zone having an air ratio of 1.5 or more. The actual combustion temperature can be arbitrarily set (up to 1200 ° C.) by adjusting the amount of air supplied from the fuel / air supply means (and / or the secondary air supply means).

  In the invention of (7), the fuel can be well mixed (floating and dispersed) in the air in the mixing chamber.

  In the invention of (8), since the multiphase flow swirling in the mixing chamber is discharged from the discharge port, an ignition flame holding region having an air ratio suitable for ignition and flame holding is formed near or downstream of the discharge port. Is possible. Furthermore, since the flame holding plate is provided in the vicinity of the peripheral wall of the discharge port, ignition and flame holding can be performed more stably and / or easily. In the invention of (8), the combustion efficiency can be improved and / or combustion with little unburned content can be achieved by high-temperature combustion of the multiphase flow with the flame holding plate.

  In invention of (9), the combustion furnace which has a burner apparatus excellent in ignition and flame holding property is provided.

  In the invention of (10), it is possible to prevent useless use of fuel (such as petrochemical fuel) in the ignition burner.

Graph showing the correlation between air ratio and solid-gas ratio for various powdered fuels Graph showing an example of correlation between air ratio and theoretical adiabatic temperature in biomass fuel Explanatory drawing which shows the combustion furnace and burner apparatus according to preferable embodiment Explanatory drawing which shows distribution of the example air ratio formed in the discharge opening vicinity of a burner apparatus Explanatory drawing which shows the burner apparatus which concerns on other preferable embodiment. Explanatory drawing showing an exemplary structure of a combustion furnace Explanatory drawing which shows the burner apparatus according to other preferable embodiment.

  FIG. 3 is an explanatory diagram showing the combustion furnace 10 and the burner device 20 according to a preferred embodiment.

  As shown in FIG. 3A, the burner device 20 of this embodiment has a primary nozzle 30. The primary nozzle 30 has a mixing chamber 31 and a discharge port 33. The mixing chamber 31 is a space for mixing the fuel T and the primary air A1. The shape of the mixing chamber 31 is arbitrary. In a preferred embodiment, the mixing chamber 31 has a cylindrical shape. The primary nozzle 30 can be formed of stainless steel or the like.

  The primary nozzle 30 has a primary air supply port 40 for supplying the primary air A1 to the mixing chamber 31. The primary air supply port 40 may be disposed in the upper part of the mixing chamber 31. FIG. 3B shows the flow of the primary air A1 in the mixing chamber 31 when the mixing chamber 31 is viewed from above. As shown in FIG. 3B, the primary air A <b> 1 from the primary air supply port 40 is supplied in such a direction that a swirling flow is formed by the primary air A <b> 1 in the mixing chamber 31. In a preferred embodiment, the primary air A <b> 1 is supplied toward the tangential direction of the peripheral wall 32 of the mixing chamber 31. The burner device 20 may have a pipe 41 and a blower (not shown) for supplying the primary air A1 to the primary air supply port 40.

  The burner device 20 has a fuel supply unit 50 for supplying the fuel T to the mixing chamber 31. The fuel supply unit 50 may be disposed on the ceiling 34 of the mixing chamber 31. The fuel supply unit 50 has a fuel supply port 51 that communicates with the mixing chamber 31. In the preferred embodiment, as shown in FIG. 3B, the fuel supply port 51 is positioned eccentric to the primary nozzle 30 (above the primary air A <b> 1 blown from the primary air supply port 40. ). As the fuel T, a powdery fuel, in particular, a powdery biomass fuel can be used. The fuel T is preferably supplied by a method of dropping from the fuel supply port 51 by its own weight. The method of conveying the fuel to the fuel supply port 51 is arbitrary. For example, mechanical conveyance (for example, a screw feeder etc.), pneumatic conveyance, combined use of both, etc. are possible.

  The fuel T supplied from the fuel supply port 51 flows by the primary air A1 blown from the primary air supply port 40, and the mixed phase flow of the fuel T and the primary air A1 swirls in the mixing chamber 31. Due to the centrifugal force generated by the swirling of the multiphase flow, a high concentration multiphase flow having a high concentration of fuel T (low air ratio λ) is formed in a portion far from the center of the mixing chamber 31 (near the peripheral wall 32). A low-concentration multiphase flow in which the concentration of the fuel T is lower than the high-concentration multiphase flow (the air ratio λ is large) is formed near the center. In order to satisfactorily mix (floating and disperse) the fuel T in the primary air A1, it is desirable that the particle size of the fuel T be as small as possible. The particle size of the fuel T is preferably 3 mm or less, more preferably 1 mm or less, and particularly preferably 0.5 mm or less.

  The high-concentration multiphase flow moves downward in the mixing chamber 31 while swirling, and is eventually discharged downstream from the discharge port 33.

  FIG. 4 shows an exemplary air ratio distribution (contour lines) formed near the discharge port 33. The high-concentration multiphase flow discharged from the discharge port 33 has the highest air ratio λ at the discharge port 33, and the farther away from the discharge port 33 due to mixing with the low-concentration multiphase flow or the secondary air A <b> 2 (toward the downstream side). The air ratio λ increases. Therefore, the supply conditions of the fuel T and / or the primary air A1 from the primary air supply port 40 and the fuel supply port 51 are appropriately adjusted, and the air ratio λ of the high-concentration multiphase flow at the discharge port 33 is set to the ignition flame holding range. By making it smaller than (for example, 0.5-0.8), the area | region (ignition flame holding area | region R1) where air ratio (lambda) becomes an ignition flame holding range can be formed in the downstream of the discharge port 33. .

  On the downstream side of the ignition flame holding region R1, the air ratio λ is further increased, and a combustion region R2 having an air ratio (for example, 1.5 or more) suitable for complete combustion of the fuel T can be formed.

  A flame holding plate 60 is disposed at the discharge port 33 (near the discharge port 33 or downstream thereof). The flame holding plate 60 is disposed on the flow path of the high concentration mixed phase flow (in the vicinity of the peripheral wall 32). Since the flame holding plate 60 of the discharge port 33 interferes with the high-concentration multiphase flow, the ignition flame holding region R1 is formed more stably and / or the ignition and flame holding stability in the ignition flame holding region R1 is improved. improves. The ignition flame holding region R1 can be formed near the flame holding plate 60 or downstream thereof.

  The flame holding plate 60 may have an arbitrary shape. In a preferred embodiment, the flame holding plate 60 has a disk shape with an opening formed in the center. The flame holding plate 60 in FIGS. 3 and 4 is attached so that no gap is formed between the flame holding plate 60 and the peripheral wall 32, but it is also possible to form a gap between the flame holding plate 60 and the peripheral wall 32.

  It has been experimentally confirmed that when the flame holding plate 60 is cooled by the temperature and supply speed of the primary air A1 and / or the fuel T, the ignition and flame holding at the flame holding plate 60 may become unstable. It was. In order to prevent this, it is preferable that the flame holding plate 60 has a heat insulating structure by the heat insulating material 61 or the like. The high temperature ignition temperature can be maintained by the heat insulating material 61. In the figure, the case where the heat insulating material 61 is provided only on the upper surface of the flame holding plate 60 is shown. It is also possible to provide a heat insulating material 61 on the entire circumference of the flame holding plate 60. The heat insulating material 61 can be made of a low thermal conductivity material such as ceramics.

  The burner device 20 may further include a secondary nozzle 70 for supplying the secondary air A2 in the vicinity of the flame holding plate 60 or downstream thereof. By having the secondary nozzle 70, the stable formation of the ignition flame holding region R1 is facilitated, and / or the adjustment of the air ratio λ in the vicinity of the flame holding plate 60 or downstream thereof is facilitated. The secondary nozzle 70 can be formed of stainless steel or the like.

  In the embodiment of FIG. 3, the secondary nozzle 70 has a cylindrical air passage 71 that concentrically surrounds the primary nozzle 30 and a secondary air supply port 72 that supplies the secondary air A <b> 2 to the air passage 71. The secondary air A2 from the ventilation path 71 can be uniformly discharged from the entire circumferential direction toward the flame holding plate 60 or the downstream side thereof. The secondary nozzle 70 may have a pipe 73 and a blower (not shown) for supplying the secondary air A2 to the ventilation path 71.

  FIG. 3C shows the flow of the secondary air A2 in the ventilation path 71 when the ventilation path 71 is viewed from above. Preferably, the secondary air A2 is supplied to the ventilation path 71 in such a direction that a swirling flow is formed by the secondary air A2 in the ventilation path 71 as shown in FIG. The secondary air A <b> 2 can be supplied toward the tangential direction of the peripheral wall 74 of the ventilation path 71. Preferably, the swirl directions of the primary air A1 in the mixing chamber 31 and the secondary air A2 in the ventilation path 71 are the same direction. This prevents the swirling flow of the primary air A1 in the mixing chamber 31 from being disturbed.

  The combustion furnace 10 or the burner device 20 may have an ignition burner (pilot burner) 80. The ignition burner 80 is attached to a position where the fuel T (high-concentration multiphase flow) near the flame holding plate 60 or downstream thereof can be ignited. The ignition burner 80 is used for initial ignition, and the ignition burner 80 may be extinguished when ignition and flame holding are confirmed (when the flame is stabilized). Flame holding can be confirmed by installing a flame detector in the vicinity of the flame holding plate 60, or the furnace temperature (for example, the temperature at an appropriate location in the combustion chamber 90) exceeds a preset temperature (determination temperature). It can be regarded as a flame holding confirmation. The determination temperature is preferably about 350 ° C. or higher, more preferably 400 ° C. or higher, although it depends on the fuel component and moisture content. For example, the upper limit of the determination temperature may be 600 ° C. or 500 ° C.

  The combustion furnace 10 may have a combustion chamber 90. By having the combustion chamber 90 having an appropriate configuration according to the use (for example, generation of high-temperature combustion gas, generation of high-temperature high-pressure steam, etc.), the burner device 20 can effectively use flames and combustion heat.

  FIG. 5 shows a burner device 120 according to another embodiment.

  The burner device 120 includes a second flame holding plate 62 on the downstream side of the flame holding plate 60 in addition to the same configuration as the burner device 20.

  In order to supply the fuel T uniformly, the size (size) of the fuel supply port 51 is limited to some extent (if it is too large, the fuel T cannot be supplied uniformly), and the size of the fuel supply port 51 and the supply of the fuel T are limited. The appropriate size of the primary air supply port 40 and the appropriate air volume of the primary air A1 are determined to some extent according to the speed. For this reason, it is difficult to keep the concentration of the high-concentration multiphase flow in the primary nozzle 30 constant with respect to the change in the load (supply speed of the fuel T). The concentration of the high concentration multiphase flow increases. If the concentration of the high-concentration multiphase flow increases too much, the air ratio in the vicinity of the flame holding plate 60 or downstream thereof becomes smaller than the ignition flame holding region range, and the ignition becomes unstable, resulting in discharge of unburned components, etc. Can cause problems.

  The burner device 120 copes with such a problem, and the concentration of the high-concentration multiphase flow in the primary nozzle 30 becomes high. Therefore, an ignition flame holding region R1 is formed near the flame holding plate 60. Even if it disappears, an ignition flame holding region R3 in which the air ratio λ falls within the ignition flame holding range can be formed on the downstream side of the second flame holding plate 62. As described above, when the load is small, the flame holding plate 60 (ignition flame holding region R1) can hold the flame, and when the load is large, the second flame holding plate 62 (ignition flame holding region R3) can hold the flame. Thus, the burner device 120 having a large allowable range with respect to the load change can be realized. FIG. 5 shows a case where a gap between the peripheral wall of the second nozzle 70 and the second flame holding plate 62 is formed, but such a gap may not be present.

  The burner device 120 may further include tertiary air supply means for supplying the tertiary air A3 in the vicinity of the second flame holding plate 62 or downstream thereof. Thereby, adjustment of the air ratio in the ignition flame holding region R3 can be facilitated.

  The tertiary air supply means may have a tertiary nozzle having the same configuration as the secondary nozzle 70. That is, the tertiary nozzle has a second ventilation path that surrounds the outer periphery of the secondary nozzle 70, and is uniform from the entire circumferential direction from the downstream end of the second ventilation path toward the second flame holding plate 62 or the downstream side thereof. Tertiary air A3 may be supplied. In the second ventilation path, the tertiary air A3 can be swirled in the same direction as the air A1, A2 in the mixing chamber 31 and the ventilation path 71.

  In the conventional powder burner, the load change ratio was about 1/2, but in the burner device 120 in FIG. 5, it can be up to about 1/4, which is comparable to about 1/3 to 1/5 of the oil burner. Performance is obtained. The load change ratio is a ratio between the maximum load and the minimum load that allows the fuel T to be burned well (or completely burned).

  Further, a third flame holding plate, a fourth flame holding plate, etc. may be installed on the downstream side of the second flame holding plate 62, such as a third flame holding plate, a fourth flame holding plate, etc. The fourth air supply means, the fifth air supply means,.

  The combustion furnaces of Patent Documents 1 and 2 require separate (two) combustion chambers for good combustion (or complete combustion) of the pulverized fuel. In contrast, the burner devices 20 and 120 of the present application do not require such a separate combustion chamber. Therefore, it is easy to change the nozzle direction, add or change the flame holding plate, or add or change the air supply. Thereby, when adding a burner apparatus to the combustion furnace for solid fuel, flexible arrangement | positioning according to the structure of a combustion furnace is attained.

  For example, the gasification facility of Patent Document 3 is for generating fuel gas by steam reforming reaction of biomass raw material, but for generating solid fuel for generating high-temperature combustion gas necessary as a heat source for steam reforming reaction. The combustion furnace (hot gas generator) is used.

  FIG. 6 shows an example of the structure of a combustion furnace 201 for solid fuel that can be used as the combustion furnace of Patent Document 3.

  In the combustion furnace 201 in FIG. 6, solid (chip-like, pellet-like, etc.) fuel T1 such as biomass is supplied from the fuel supply device 210 onto the grate 212 and is burned. Combustion air A4 and A5 are supplied from the upper part (combustion chamber 211) and lower part (furnace bottom part 213) of the grate 212, and the high-temperature combustion gas G generated by the combustion is sent from the exhaust pipe 214 to another place. It is used for various purposes (for example, steam reforming reaction of biomass feedstock).

  In such a combustion furnace 201, a method of dropping the fuel T1 by its own weight from the upper part of the grate 212 (the ceiling part of the combustion chamber 211) is generally used from the convenience of supply of the fuel T1. Therefore, a vertical burner device may not be added to the ceiling portion of the combustion chamber 211.

  However, since the burner devices 20 and 120 have a simple structure as described above (a separate combustion chamber is not required), the burner devices 20 and 120 are set sideways (sideways) as shown by a broken line in FIG. It is easy to add to the side. Thereby, the combustion furnace 201 capable of both the operation with the solid fuel T1 and the operation with the pulverized fuel T can be realized. Thus, the burner apparatus of this application is excellent in the flexibility of arrangement | positioning at the time of adding to various types of combustion furnaces.

  FIG. 7 (A) is a burner device 320 of an embodiment suitable for use in the horizontal orientation as shown in FIG. 6, and FIG. 7 (B) is an XX cross-sectional view thereof.

  In the burner device 320, a fuel supply port 351 for supplying the fuel T is provided on the side surface of the primary nozzle 30. Even when the burner device 320 is placed sideways, the fuel T is generated by its own weight (without using air conveyance). Can be supplied to the mixing chamber 31. Therefore, there is no need to be restricted by the solid-gas ratio in the case of air conveyance.

  FIG. 7C shows a burner device 420 according to a further modification, and has the same configuration as the burner device 320 except that the fuel supply port 451 is provided on the pipe 41 for supplying the primary air A1. As with the burner device 320, the fuel T can be supplied by its own weight.

  The burner device and the combustion furnace of the preferred embodiment have been described above. However, the structure, shape, dimensions, material, operation, function, use, etc. in the embodiment are described as preferred examples, and these are within the scope of the claims. The invention is not limited.

  With this application, energy can be used not only in the form of solids but also in the form of powders in the use of energy by burning biomass and the like, greatly expanding the range of utilization of powdered fuels, as well as various combustion furnaces and load conditions. A burner device that can be flexibly adapted and a highly useful combustion furnace are provided.

  Combustion capable of using both solid fuel and pulverized fuel if the burner device of the present application is applied to a solid fuel combustion furnace for high temperature combustion gas generation, for example, a grate type combustion furnace A furnace is realized, or combustion of solid fuel can be supported by a burner device.

  In addition, it is possible to improve the overall thermal efficiency of electric power or plants (gasification facilities or liquid fuel generation facilities using gas fuel generated by gasification facilities). Contributes and has significant industrial effects.

DESCRIPTION OF SYMBOLS 10 ... Combustion furnace 20 ... Burner apparatus 30 ... Primary nozzle 31 ... Mixing chamber 32 ... Perimeter wall 33 ... Outlet 34 ... Ceiling 40 ... Primary air supply port 41 ... Piping 50 ... Fuel supply part 51 ... Fuel supply port 60 ... Flame holding plate 61 ... Heat insulating material 62 ... Flame holding plate 70 of the secondary nozzle ... Secondary nozzle 71 ... Ventilation path 72 ... Secondary air supply port 73 ... Pipe 74 ... peripheral wall 80 ... ignition burner 90 ... combustion chamber 120 ... burner device 201 ... combustion furnace 210 ... Fuel supply device 211 ... Combustion chamber 212 ... Grate 213 ... Furnace bottom 214 ... Exhaust pipe 320 ... Burner device 351 ... Fuel supply port 420 ... Burner device 451 ... Fuel supply ports A1 to A5 ... Air G ... High-temperature combustion gas R1 ... Ignition Flame zone R2 · · · combustion zone R3 · · · ignition flame stabilization zone T, T1 · · · Fuel

Claims (5)

A mixing chamber surrounded by a peripheral wall;
A fuel supply port for supplying fuel to the mixing chamber,
An air supply port for supplying primary air to the mixing chamber;
An outlet for discharging the fuel mixed in the mixing chamber and primary air;
A burner apparatus comprising a flame stabilizing plate arranged in the vicinity of the peripheral wall of the outlet,
The mixing chamber is a vertical mixing chamber in which fuel is dropped and supplied to the mixing chamber by its own weight from the fuel supply port,
The burner device , wherein the air supply port supplies the primary air toward a tangential direction of the mixing chamber so that fuel and primary air swirl in the mixing chamber .   An ignition flame holding region having an air ratio of 0.2 to 1 near the flame holding plate or downstream thereof is further provided with secondary air supply means for supplying secondary air in the vicinity of the flame holding plate or downstream thereof. The burner device according to claim 1, wherein: is formed.   The burner apparatus according to claim 1 or 2, further comprising tertiary air supply means for supplying tertiary air. The fuel is any one of a burner apparatus according to claim 1 to 3, characterized in that the powder fuel. A burner device according to any one of 請 Motomeko 1-4,
A combustion furnace having a combustion chamber disposed downstream of the discharge port .

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