WO2020179593A1

WO2020179593A1 - Solid fuel burner

Info

Publication number: WO2020179593A1
Application number: PCT/JP2020/007934
Authority: WO
Inventors: 裕三川添; 嶺　聡彦; 倉増　公治; 佑介越智; 谷口　斉; 恒輔北風
Original assignee: 三菱日立パワーシステムズ株式会社
Priority date: 2019-03-01
Filing date: 2020-02-27
Publication date: 2020-09-10
Also published as: KR20210134356A; TW202102799A; WO2020178880A1; JPWO2020179593A1

Abstract

A fuel concentrator (34), which is provided toward the center of a fuel nozzle (21) and which imparts to a mixed fluid a velocity component away from the center of the fuel nozzle (21), is configured so as to have a plurality of blades (41a, 41b) that impart a swirl to the mixed fluid, and the deflection angle of the blade (41a) relative to the burner axial direction can be adjusted; thus, it is possible to switch between the use of coal and biomass fuel while maintaining ignitability and the risk of abrasion.

Description

Solid fuel burner

The present invention relates to a solid fuel burner that conveys and burns solid fuel, and particularly to a solid fuel burner suitable for fuel particles having a large particle size such as biomass particles.

As a method of improving the ignitability of the solid fuel burner used in the boiler of a thermal power plant and the stability of the flame, there is a method of increasing the fuel concentration or increasing the oxygen concentration of the fuel carrier gas.

For example, in Patent Document 1 (Patent No. 5886031 specification: JP 5886031 B2), a swirl vane (16) is arranged in the flow path of the biomass fuel injection nozzle (11) to make a swirl flow, thereby making the fuel flow to the outer periphery. It is described to concentrate in part. In Patent Document 1, a swirl degree adjusting plate (17) is arranged on the downstream side of the swirl vanes (16) to adjust swirling of the fuel flow.

In patent document 2 (patent No. 6231047 specification: JP 6231047 B2), a first swirler (6) for imparting swirl to the mixed fluid and a first swirler (at the center of the primary air nozzle (9) The technique of providing the 2nd turning device (7) which gives a turning in the direction opposite to 6) is described. In the technique described in Patent Document 2, the first swirler (6) strongly swirls the mixed fluid to move the solid fuel particles to the outer peripheral side of the primary air nozzle, and the second swirler (7) moves the solid fuel particles to the outer peripheral side. The swirl of the mixed fluid is weakened by imparting a swirl in the direction opposite to that of the one swirler (6). Therefore, while the solid fuel particles are concentrated around the flame stabilizer (10) installed in the opening of the burner, the mixed fluid with less swirling flows out from the opening to improve the ignitability.

In Patent Document 3 (US Patent Publication No. 2013/0305971: US 2013/0305971 A1), a spiral blade-shaped deflecting means (deflection means 17,18,19) is provided in a flow channel (flow channel 5), A technique for concentrating fuel on the outer peripheral side of the flow channel 5 is described.

In Patent Document 4 (Chinese Patent Publication No. 101832551 gazette: CN 101832551A), a conical member (10) that moves the flow to the outer peripheral side is arranged upstream of the member (11) that imparts swirl. .. In Patent Document 4, the cone-shaped member (10) and the member (11) that imparts a turn are configured by rod-shaped members (19, 20) so that their axial positions can be adjusted.

Japanese Patent No. 5886031 ([0030]-[0031], FIGS. 1-3, 21) Japanese Patent No. 6231047 ([0048]-[0061], FIGS. 1-3, 21) U.S. Patent Publication No. 2013/0309571 ([0041]-[0043], Fig. 1) Chinese Patent Publication No. 101832551 ([0036]-[0038], FIG. 1)

Due to social demands such as measures against global warming, a solid fuel burner using a biomass fuel is required as in the technique described in Patent Document 1. However, at present, the supply of biomass fuel is not stable. Therefore, it is desirable that coal and biomass can be switched and used according to the situation of fuel procurement.
In the burners described in Patent Documents 1 to 4, the mixed fluid is swirled to concentrate the fuel on the outer peripheral side. Here, as compared with coal, the biomass fuel has a lower risk of wear when colliding with a member that imparts a swirl. The ignitability of biomass fuel is lower than that of coal, and the risk of burnout is lower.

Therefore, if coal fuel is simply used for the burner for biomass fuel described in Patent Document 1, there is a high risk of wear and high ignitability, but there is a problem of easy burning. On the contrary, when biomass fuel is used in the burners for pulverized coal described in Patent Documents 2 to 4, there is a problem that it is hard to wear but has low ignitability.

The present invention has a technical problem of enabling switching between coal and biomass fuels while maintaining the risk of wear and ignitability.

In order to solve the technical problem, the solid fuel burner of the invention according to claim 1 is
A fuel nozzle in which a mixed fluid of solid fuel and its carrier gas flows and opens toward the furnace,
A combustion gas nozzle arranged on the outer peripheral side of the fuel nozzle to eject a combustion gas,
A fuel concentrator provided on the center side of the fuel nozzle and imparting a velocity component in a direction away from the center of the fuel nozzle to the mixed fluid.
A solid fuel burner comprising:
The fuel concentrator has a plurality of blades that give swirling to the mixed fluid, and is characterized in that the runout angle of the blades with respect to the burner axis direction is adjustable.

The invention according to claim 2 is the solid fuel burner according to claim 1.
In addition to being installed at two locations separated from the burner axis direction, the turning directions of the plurality of blade structures are opposite to each other, and the swing angle of the blades on at least the upstream side with respect to the flow direction of the mixed fluid is adjusted. It is characterized by being possible.

The invention according to claim 3 provides the solid fuel burner according to claim 1,
The fuel concentrator is configured to be movable along the burner axis direction.

In order to solve the technical problem, the solid fuel burner of the invention according to claim 4 is used.
A fuel nozzle in which a mixed fluid of solid fuel and its carrier gas flows and opens toward the furnace,
A combustion gas nozzle arranged on the outer peripheral side of the fuel nozzle to eject a combustion gas,
A fuel concentrator provided on the center side of the fuel nozzle and imparting a velocity component in a direction away from the center of the fuel nozzle to the mixed fluid.
A solid fuel burner comprising:
The fuel concentrator has a plurality of blades that give a swirl to the mixed fluid, and is installed at two positions apart from the burner axial direction, and the swirling direction of each of the plurality of blade structures is opposite.
The fuel concentrator is configured to be movable along the burner axis direction.

The invention according to claim 5 provides the solid fuel burner according to claim 4,
The fuel concentrator is characterized in that at least the runout angle of the blade on the upstream side with respect to the flow direction of the mixed fluid with respect to the burner axial direction is adjustable.

The invention according to claim 6 provides the solid fuel burner according to any one of claims 1 to 5,
A shaft portion supporting the blade,
A spraying device that sprays a cleaning gas toward the boundary between the blade and the shaft,
It is characterized by having.

The invention according to claim 7 provides the solid fuel burner according to claim 6,
The spraying device having a spout for ejecting gas in the radial direction from the shaft portion and a gas guide member for guiding gas from the spout to a boundary portion between the blade and the shaft portion.
It is characterized by having.

According to the first aspect of the invention, since the deflection angle of the blade of the fuel concentrator can be adjusted, the deflection angle can be adjusted according to the fuel used, and the risk of wear and ignitability are maintained. At the same time, coal and biomass fuel can be switched and used.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, at least the deflection angle of the blade on the upstream side can be adjusted, and the deflection of the blade on the upstream side can be adjusted according to the fuel used. The angle can be adjusted and the swirl of the mixed fluid can be weakened by the blades on the downstream side. Therefore, the spread of the jet of the mixed fluid can be adjusted.

According to the invention described in claim 3, in addition to the effect of the invention described in claim 1, the position along the burner axial direction of the fuel concentrator can be adjusted according to the fuel used, and burnout You can deal with risks.

According to the invention described in claim 4, since the fuel concentrator having the blades in the opposite directions is movable in the axial direction, the position in the axial direction can be adjusted according to the fuel used, and the fuel concentrator can be used against wear. Coal and biomass fuels can be switched and made available while maintaining risk and ignitability.

According to the invention described in claim 5, in addition to the effect of the invention described in claim 4, since the deflection angle of at least the upstream blade can be adjusted, the deflection angle is adjusted according to the fuel used. Therefore, it is possible to deal with the risk of wear and the risk of ignitability and burnout.

According to the invention described in claim 6, in addition to the effect of the invention described in any one of claims 1 to 5, it is possible to suppress the accumulation of fine particles of the solid fuel at the boundary between the blade and the shaft. Therefore, it is possible to prevent the runout angle from being adjusted and the fuel concentrator from being unable to move due to the accumulation of fine particles.

According to the invention of claim 7, in addition to the effect of the invention of claim 6, the gas ejected from the ejection port is guided by the gas guide member, and the accumulation of fine particles is suppressed with a simple configuration. it can.

FIG. 1 is an overall explanatory diagram of a combustion system according to a first embodiment of the present invention. FIG. 2 is an explanatory diagram of the solid fuel burner of the first embodiment. 3A and 3B are explanatory views of a swing angle tilting mechanism of the blade of the fuel concentrator of the embodiment, FIG. 3A is a sectional view of a main part, FIG. 3B is an explanatory view of a high angle position, and FIG. ) Is an explanatory view of a low angle position. FIG. 4 is an explanatory diagram of analysis results of the position of the downstream blade and the opening diameter for the coal fuel and the biomass fuel. FIG. 5: is explanatory drawing of another form 1 of this invention. 6A and 6B are explanatory views of another embodiment 2 of the present invention, FIG. 6A is a schematic view, and FIG. 6B is a partial detailed view. FIG. 7 is an explanatory view of the gas guide member in the form shown in FIG.

Next, specific examples of the embodiments of the present invention (hereinafter referred to as examples) will be described with reference to the drawings, but the present invention is not limited to the following examples. In the following description using the drawings, illustrations other than the members necessary for the description are appropriately omitted for easy understanding.

FIG. 1 is an overall explanatory view of the combustion system according to the first embodiment of the present invention.
In FIG. 1, in a combustion system (combustion apparatus) 1 of Example 1 used in a thermal power plant or the like, a biomass fuel (solid fuel) is contained in a bunker (fuel hopper) 4. The biomass fuel of the bunker 4 is crushed by the mill (crusher) 5. The crushed fuel is supplied to the solid fuel burner 7 of the boiler 6 through the fuel pipe 8 and burned. A plurality of solid fuel burners 7 are installed in the boiler 6.

The exhaust gas discharged from the boiler 6 is denitrated by the denitration device 9. The denitrated exhaust gas passes through the air preheater 10. In the air preheater 10, heat exchange between the air sent from the blower 11 and the exhaust gas is performed. Therefore, the temperature of the exhaust gas is lowered and the air from the blower 11 is heated. Air from the blower 11 is supplied to the solid fuel burner 7 and the boiler 6 as combustion air through the air pipe 12.
The exhaust gas that has passed through the air preheater 10 is recovered in heat when passing through the gas gas heater (heat recovery device) 13, and is cooled down.

The exhaust gas that has passed through the gas gas heater (heat recovery device) 13 is recovered and removed by the dry dust collector 14.
The exhaust gas that has passed through the dry dust collector 14 is sent to the desulfurization device 15 to be desulfurized.
The exhaust gas that has passed through the desulfurization device 15 is collected and removed by the wet dust collector 16 such as dust in the exhaust gas.
The exhaust gas that has passed through the wet dust collector 16 is reheated by the gas gas heater (reheater) 17.
The exhaust gas that has passed through the gas gas heater (reheater) 17 is exhausted to the atmosphere from the chimney 18.
The mill 5 itself may have various conventionally known configurations, and is described in, for example, Japanese Unexamined Patent Publication No. 2010-242999, so detailed description thereof will be omitted.

FIG. 2 is an explanatory diagram of the solid fuel burner of the first embodiment.
3A and 3B are explanatory views of a swing angle tilting mechanism of the blades of the fuel concentrator of the embodiment. FIG. 3A is a sectional view of a main part, FIG. 3B is an explanatory view of a high angle position, and FIG. ) Is an explanatory view of a low angle position.
In FIG. 2, the solid fuel burner 7 of the first embodiment has a fuel nozzle 21 through which a carrier gas flows. The downstream end opening of the fuel nozzle 21 is provided in the wall surface (furnace wall, water tube wall) 23 of the furnace 22 of the boiler 6. In the fuel nozzle 21, the fuel pipe 8 is connected to the upstream end. The fuel nozzle 21 is formed in a hollow tubular shape, and a flow path 24 through which solid fuel (crushed biomass fuel and coal fuel) and a transport gas flow is formed inside the fuel nozzle 21.

An inner combustion gas nozzle (secondary combustion gas nozzle) 26 that ejects combustion air to the furnace 22 is installed on the outer periphery of the fuel nozzle 21. Further, an outer combustion gas nozzle (third combustion gas nozzle) 27 is installed on the outer peripheral side of the inner combustion gas nozzle 26. The

combustion gas nozzles

26 and 27 eject the air from the wind box 28 into the furnace 22. In the first embodiment, a guide vane 26a is formed at the downstream end of the inner combustion gas nozzle 26 so as to incline radially outward with respect to the center of the fuel nozzle 21 (the diameter increases toward the downstream side). .. Further, a throat portion 27a along the axial direction and an enlarged portion 27b parallel to the guide vane 26a are formed in the downstream portion of the outer combustion gas nozzle 27. Therefore, the combustion air ejected from the

combustion gas nozzles

26 and 27 is ejected so as to diffuse from the center in the axial direction.

A flame stabilizer 31 is supported at the opening at the downstream end of the fuel nozzle 21. In FIG. 2, the flame stabilizer 31 is formed with an inner peripheral projection 31a. The inner peripheral side protrusions 31a are formed so as to project toward the center side of the fuel nozzle 21, and the inner peripheral side protrusions 31a are periodically arranged at intervals along the circumferential direction.
At the center of the cross section of the flow path of the fuel nozzle 21, a tubular or rod-shaped central shaft member is provided so as to penetrate the collision plate 32a supported by the collision plate flange 21a of the fuel nozzle 21, whereby the fuel concentrator 34 The first swirler 41 on the upstream side and the second swirler 42 on the downstream side are supported.
In the example shown in FIGS. 2 and 3, the oil starting burner (oil gun) 32 is arranged so as to penetrate therethrough. The oil starting burner 32 is supported in a state of penetrating the collision plate 32a supported by the collision plate flange 21a of the fuel nozzle 21.

A protective cylinder 32 b for protecting the oil starting burner 32 is attached to the outer periphery of the oil starting burner 32. A fuel concentrator 34 is supported on the outer periphery of the protective cylinder 32b. In the fuel concentrator 34, an inner cylinder 35 arranged on the outer peripheral side of the protective cylinder 32b and an outer cylinder 36 arranged on the outer peripheral side of the inner cylinder 35 are arranged. The outer cylinder 36 is supported by the collision plate 32a via a support (not shown). Therefore, the inner cylinder 35 is supported so as to be slidable in the axial direction with respect to the protection cylinder 32b of the oil starting burner 32 and the outer cylinder 36. The outer cylinder 36 is not limited to the configuration supported by the collision plate, and it is possible to change the configuration such that the outer cylinder 36 is fixed to the oil starting burner 32 at a position outside the movable range of the inner cylinder 35.
In FIG. 2, a position adjusting rod 37 as an example of a position adjusting member is supported on the inner cylinder 35. The position adjusting rod 37 is formed in a rod shape and extends parallel to the oil starting burner 32 toward the upstream side in the fluid flow direction. The upstream portion of the position adjusting rod 37 penetrates the collision plate 32a and extends to the outside of the flow path 24.
The position adjusting rod 37 may be installed so as to be built in a cylindrical or rod-shaped central shaft member, whereby wear damage due to collision of fuel particles can be avoided.

In FIG. 2, the fuel concentrator 34 has an upstream first swirler 41 and a downstream second swirler 42. 2 and 3, each of the swirlers 41 and 42 has a plurality of

blades

41a and 42a that incline the oil starting burner 32 with respect to the axis. In the first embodiment, in the second swirler 42 on the downstream side, the blades 42 a are fixedly supported on the outer peripheral surface of the outer cylinder 36.

In FIG. 3, in the first swirl 41 on the upstream side, the blade 41a is supported by the rotating shaft 43. The rotating shaft 43 is rotatably supported on the outer surface of the inner cylinder 35. The rotating shaft 43 penetrates the shaft passing portion 36a formed in the outer cylinder 36 and extending in the gas flow direction. A cam portion 44 that projects radially outward is supported on the rotating shaft 43. A pin 44a extending in parallel with the rotation shaft 43 is supported on the cam portion 44 (see FIG. 3A). The pin 44a penetrates the guide groove 36b (see FIGS. 3B and 3C). The guide groove 36b is formed in the outer cylinder 36, and is formed in an elongated hole shape capable of guiding the pin 44a.

Therefore, in the fuel concentrator 34 of the first embodiment, when the position adjusting rod 37 is inserted or pulled out in the axial direction, the inner cylinder 35 moves in the axial direction. In response to this, the pin 44a comes into contact with the guide groove 36b, the cam portion 44 rotates, and the rotating shaft 43 rotates. Therefore, the blade 41a moves between the low angle position shown in FIG. 3(C) and the high angle position shown in FIG. 3(B).
In the first embodiment, the deflection angle of the blade 42a of the second swirler 42 is set to the opposite direction and the same angle as the deflection angle of the blade 41a at the low angle position.

In the solid fuel burner 7 of the first embodiment having the above configuration, when the fuel used is biomass fuel, the position adjusting rod 37 is pushed in. Therefore, the inner cylinder 35 moves to the downstream side in the fluid flow direction. Therefore, the swirlers 41 and 42 move to the downstream side in the axial direction (the side closer to the furnace 22).
At this time, the blade 41a of the upstream first swirler 41 moves to the high angle position. Therefore, the deflection angle of the vanes 41a of the first swirler 41 becomes large.
Here, the biomass fuel has a lower ignitability than coal, and it is desired to concentrate the fuel particles to enhance the ignitability. Therefore, in the first embodiment, the deflection angle of the blade 41a is increased to strengthen the swirling of the mixed fluid. Therefore, even if biomass fuel is used, the ignitability of the fuel can be improved.

Further, in the first embodiment, the fuel concentrator 34 is moved to the downstream side, and the opening (maintenance) is opened before the fuel once moved to the outer peripheral side is reflected by the inner surface of the fuel nozzle 21 and moves to the inner peripheral side. Easy to reach flamearm 31). Therefore, compared with the case where the fuel concentrator 34 is located on the upstream side, the ignitability and the fuel concentration effect are improved.
Biomass fuel has a larger average particle size and is inferior in ignitability as compared with coal fuel, so that the radiant heat received by the burner from the flame is smaller than that in the case of coal combustion.
Therefore, the risk of burnout of the fuel concentrator 34 is lower than that at the time of coal combustion, and therefore the risk of burnout is suppressed even if the fuel concentrator 34 moves to the downstream side.
Further, since the biomass fuel has a lower risk of wear than coal, even if the deflection angle of the blade 41a is increased, the adverse effect on the life is reduced.

Further, the biomass fuel is an oxygen-containing fuel, and the amount of additional oxygen required after ignition is small. Therefore, the amount of air ejected from the outer peripheral secondary air nozzle (inner combustion gas nozzle 26) is reduced as compared with coal, and the amount of primary air that contributes to ignition is set to be larger by that amount. Here, in the first embodiment, a guide vane 26a is installed at the downstream end so that the air jet from the secondary air nozzle (inner combustion gas nozzle 26) forms a circulating flow having a large spread. .. However, when the amount of the secondary air is reduced and the amount of the primary air is set to be large, the spread of the jet flow ejected from the solid fuel burner 7 becomes relatively small.
On the other hand, in the first embodiment, when the biomass fuel is used, (the deflection angle of the first swirler 41)>(the deflection angle of the second swirler 42) is set. Therefore, the swirl strongly applied by the blade 41a on the upstream side is reduced on the downstream side, and the swirl is ejected while leaving the swirl. Therefore, the jet flow ejected from the solid fuel burner 7 is in a state in which the jet flow is effectively spread by swirling. Therefore, the spread of the jet flow is also prevented from being insufficient.

Further, in the solid fuel burner 7 of the first embodiment, when the coal (pulverized coal) fuel is used, the position adjusting rod 37 is pulled out in the axial direction. Therefore, the swirlers 41, 42 move integrally in the axial upstream side (direction away from the furnace 22). Therefore, the blade 41a of the first swirler 41 moves to the low angle position, and the deflection angle becomes small.
Therefore, the abrasion of the blades 41a due to the coal fuel is suppressed as compared with the case where the deflection angle is large. Further, since the ignitability of the coal fuel is higher than that of the biomass fuel, the ignitability can be sufficiently ensured even if the fuel concentrator 34 is on the upstream side or the turning is weak. On the other hand, since the burning risk of coal fuel is high, it is possible to reduce the burning risk of the fuel concentrator 34 located upstream, especially the risk of burning of the second swirler provided at the downstream furnace opening side. is there.

Further, in the first embodiment, in the case of coal fuel, (deflection angle of first swirler 41)=(deflection angle of second swirler 42). In the case of coal fuel, if swirling components remain in the jet, the jet may diffuse and spread too much, and a circulating flow may not be formed. When the circulation flow is not formed, there is a problem that the NOx reduction effect is reduced. On the other hand, in the first embodiment, in the coal fuel, the swirl imparted by the upstream first swirler 41 is offset by the downstream second swirler 42. Therefore, in the first embodiment, it is possible to prevent the jet flow from spreading too much in the case of coal fuel and maintain the NOx reduction effect.

FIG. 4 is an explanatory diagram of analysis results of the position of the downstream blade and the opening diameter for the coal fuel and the biomass fuel.
FIG. 4 shows the maximum and intermediate L / D when the distance from the opening end of the fuel nozzle 21 to the installation reference position of the downstream blade 42a is L and the opening diameter of the fuel nozzle 21 is D for coal and biomass. , The minimum 3 types, the maximum, middle, and minimum blade angles θ for each of the 9 types, the NOx reduction effect of the reactor outlet based on numerical analysis (CFD: Computational Fluid Dynamics) and the UBC (ash) Medium unburned carbon (Unburned Carbon) is obtained, and this is relatively evaluated as "performance" and expressed as a score. At the same time, each risk of flashback, wear, and accumulation is also scored, and the most preferable L / D and θ are It is a combination obtained.

Coal has almost no effect of θ on performance when L / D is between the minimum and intermediate (small sensitivity), but when L / D is maximum, the effect of θ is large, and when the angle is maximum, the effect of θ is large. Sufficient performance can be obtained, but performance decreases as the angle is reduced. Therefore, it is desirable to set the risk of flashback, wear, and accumulation to the minimum, that is, set L / D to the middle and θ to the minimum.
On the other hand, biomass has a greater influence of θ than any coal at any L/D (a high sensitivity), and a combination with a minimum L/D and a maximum θ is sufficient for sufficient performance. desirable. Since each risk is suppressed to be smaller than that of coal even with the combination, it is desirable to set this combination.
As described above, the desirable combination of L/D and θ that is comprehensively evaluated in terms of performance and risk differs depending on the fuel type, but according to the present invention, both can be set to appropriate conditions. ..

Therefore, in the solid fuel burner 7 of the first embodiment, the biomass fuel and the coal fuel can be switched and used by operating the position adjusting rod 37, and at the time of use, there is a risk of wear, ignitability, and burnout. Can be suppressed.
In particular, in the first embodiment, both the runout angle adjustment and the axial position adjustment are possible by operating the position adjustment rod 37. Therefore, compared with the case where the members for adjusting the deflection angle and the position in the axial direction are respectively provided, the operation is easy, the number of parts is reduced, and the cost is reduced.
It is desirable that the position adjusting rod 37 be provided with a protective cover as a measure against wear.

FIG. 5: is explanatory drawing of another form 1 of this invention.
In FIG. 5, the positions of the cam portion 44' and the guide groove 36b' are changed by 90 degrees, and the outer cylinder 36 is rotatable in the circumferential direction with respect to the oil starting burner 32. It is also possible to adopt a configuration in which the angle can be adjusted.

6A and 6B are explanatory views of another mode 2 of the present invention. FIG. 6A is a schematic view and FIG. 6B is a partial detailed view.
In FIG. 6, a gas supply pipe 101 is arranged between the outer circumference of the oil starting burner 32 and the inner cylinder 35. The gas supply pipe 101 is supported while penetrating the collision plate 32a. An oil starting burner 32 penetrates the inside of the gas supply pipe 101, and an inner cylinder 35 is movably supported on the outer surface along the gas flow direction.
The gas supply pipe 101 has a hollow interior, and is configured to allow a cleaning gas to pass therethrough. In the gas supply pipe 101, a plurality of gas ejection ports 102 are formed on the outer surface corresponding to the movable range of the inner cylinder 35.

A gas source 103 that supplies a cleaning gas to the gas supply pipe 101 is arranged outside the collision plate 32 a. As the cleaning gas, it is preferable to select a gas type that has little influence on the combustion of the solid fuel burner 7, and air, nitrogen (N ₂ ) gas, or the like can be used. The flow rate of the cleaning gas is preferably a flow rate that has little effect on the combustion of the solid fuel burner 7, and can be appropriately selected according to the specifications of the solid fuel burner 7. Therefore, as the gas source 103, any conventionally known configuration such as a fan for blowing air, a compressor, a gas cylinder and a valve can be adopted.

FIG. 7 is an explanatory view of the gas guide member in the form shown in FIG.
In FIG. 6, the gas guide member 104 is supported on the upstream side of the inner cylinder 35 with respect to the gas flow direction. The gas guide member 104 is formed in a conical shape in which the outer diameter increases toward the downstream side in the gas flow direction. In FIG. 7, in the present embodiment, the outer diameter of the gas supply pipe 101 is D1, the inner diameter of the upstream end of the gas guide member 104 is D2, the outer diameter of the downstream end of the gas guide member 104 is D3, and the block of the blade 41a. When the outer diameter of (= outer cylinder 36) is D4, the relationship of the following equation (1) is established.
D3>D4>D2>D1... Formula (1)
If D3 is too large, the amount of fine particles such as pulverized coal colliding with the gas guide member 104 increases, so it is desirable that D3 has a value as close as possible to D4.

Therefore, the gas ejected from the ejection port 102 is guided by the inner surface of the gas guide member 104 and is blown to the root portion 106 of the rotating shaft 43, that is, the range 106 including the boundary portion between the rotating shaft 43 and the blade 41a. In this embodiment, the gas is also blown to the upstream end portion 107 of the inner cylinder 35 and the corner portion 108 between the upstream end of the outer cylinder 36 and the inner cylinder 35.
The outer surface of the gas guide member 104 guides the pulverized coal or the like transferred from the upstream to the outside in the radial direction.
The spraying devices 101 to 104 of the present embodiment are configured by the members denoted by the reference signs 101 to 104.

(Operation of another mode 2)
In the embodiment shown in FIGS. 6 and 7, the root portions 106 of the blades 41a whose swing angles can be adjusted by the spraying devices 101 to 104, the upstream end portion 107 of the inner cylinder 35 which is movable in the gas flow direction, and the inner cylinder 35. The gas is blown to the upstream end portion 108 of the outer cylinder 36, which is the boundary portion with the.
In a configuration in which gas is not sprayed on the root portion 106, fine particles such as pulverized coal may accumulate over time according to the specifications of the solid fuel burner 7. If the fine particles are accumulated or fixed, the root portion of the blade 41a is clogged with the fine particles, so that the runout angle of the blade 41a may not be adjustable. Further, if the

respective parts

107 and 108 are clogged with fine particles, there is a possibility that the inner cylinder 35 cannot be moved in the gas flow direction.

On the other hand, in the present embodiment, the spraying devices 101 to 104 spray the gas to each part 106 to 108, and the accumulation of fine particles is suppressed. Therefore, it is possible to stably adjust the deflection angle of the blade 41a and the position in the gas flow direction for a long period of time.
In this embodiment, the gas guide member 104 is configured to be integrally movable with the inner cylinder 35, and the positional relationship with the gas guide member 104 does not change even if the inner cylinder 35 moves. Therefore, the gas can be stably blown to the respective parts 106 to 108.

Further, in the present embodiment, the ejection port 102 is formed so as to correspond to the moving range of the inner cylinder 35. Therefore, even if the inner cylinder 35 moves, the gas can be stably fed to the inner surface side of the gas guide member 104.
Further, in this embodiment, the gas can be blown with the simple structure of the gas guide member 104, and the accumulation of fine particles can be suppressed.

(Other examples of changes)
Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. It is possible.
For example, although the configuration in which the deflection angle of only the upstream blade 41a can be adjusted has been illustrated, the deflection angle of the downstream blade 42a can also be adjustable.
Further, the configuration of the two-stage

combustion gas nozzles

26 and 27 having the secondary combustion gas nozzle 26 and the tertiary combustion gas nozzle 27 has been illustrated, but the configuration is not limited to this, and the combustion gas nozzle is one stage or three stages or more. It is also possible to do so.

Further, the configuration in which one deflection rod 37 is used to adjust the deflection angle and the axial position is illustrated, but the invention is not limited to this. It is also possible to provide a member for adjusting the deflection angle and a member for adjusting the position in the axial direction, respectively. For example, the rotary shaft of the blades (fulcrum for adjusting the deflection angle) is installed in a double cylindrical inner cylinder that is slidable relative to each other, and a cam movable mechanism as shown in FIG. It is possible to adjust the deflection angle of the swirl vane by shifting the relative positional relationship between the cylinder and the outer cylinder or rotating one of the cylinders around the axis. The axial position can be adjusted by sliding the inner cylinder and the outer cylinder integrally in the nozzle axial direction. Note that the relative rotation of the inner cylinder and the outer cylinder and the movement in the nozzle axis direction can be operated, for example, by providing rods respectively. Then, depending on the type of fuel to be used, design, specifications, etc., when it is not necessary to adjust the deflection angle, the fuel concentrator 34 may be configured to have only the function of moving in the nozzle axis direction, If it is not necessary to move the nozzle in the axial direction, it is possible to configure the configuration so that only the runout angle can be adjusted.

Further, it is desirable that the fuel concentrator 34 has a first swirler 41 and a second swirler 42, but it is also possible to have only the first swirler 41 and three or more swirlers. It is also possible to adopt a configuration provided with.

In the modes shown in FIGS. 6 and 7, the configurations of the spraying devices 101 to 104 are not limited to the illustrated configurations, and can be arbitrarily changed. For example, the shape of the gas guide member is not limited to a conical shape, and may be any shape such as a parabola shape or a polygonal pyramid shape. Further, the structure of the gas supply pipe 101 having a cylindrical tubular shape along the oil starting burner 32 has been illustrated, but the present invention is not limited to this. For example, it is also possible to extend the pipe from the inner combustion gas nozzle 26 so as to cross the flow path 24 to supply air. In particular, in the configuration in which the oil starting burner 32 is not provided and the first swirler 41 and the second swirler 42 are connected by a spindle-shaped member extending in the gas flow direction, the inner combustion gas nozzle 26 A configuration in which the pipe is extended from is particularly preferable. Further, the spraying devices 101 to 104 can be provided on both the upstream first swirler 41 and the downstream second swirler 42, or only on the upstream first swirler 41 side. Is also possible.

7... Solid fuel burner,
21... Fuel nozzle,
22... furnace,
26, 27... Combustion gas nozzle,
34... Fuel concentrator,
41a... blades on the upstream side,
41a, 41b... blades,
43... Shaft,
101 to 104... Spraying device,
102... the spout,
104... Gas guide member.

Claims

A fuel nozzle in which a mixed fluid of solid fuel and its carrier gas flows and opens toward the furnace,
A combustion gas nozzle arranged on the outer peripheral side of the fuel nozzle to eject a combustion gas,
A fuel concentrator provided on the center side of the fuel nozzle and imparting a velocity component in a direction away from the center of the fuel nozzle to the mixed fluid.
A solid fuel burner comprising:
The solid fuel burner is characterized in that the fuel concentrator has a plurality of blades that swirl the mixed fluid, and the deflection angle of the blade with respect to the burner axis direction is adjustable.
The blades are installed at two locations apart from the burner axial direction, and the swirling directions of the plurality of blade structures are opposite to each other, and the deflection angle of the blades at least upstream with respect to the flow direction of the mixed fluid is adjusted. Solid fuel burner according to claim 1, characterized in that it is possible.
The solid fuel burner according to claim 1, wherein the fuel concentrator is configured to be movable along the burner axial direction.
A fuel nozzle in which a mixed fluid of solid fuel and its carrier gas flows and opens toward the furnace,
A combustion gas nozzle arranged on the outer peripheral side of the fuel nozzle to eject a combustion gas,
A fuel concentrator provided on the center side of the fuel nozzle and imparting a velocity component in a direction away from the center of the fuel nozzle to the mixed fluid.
A solid fuel burner comprising:
The fuel concentrator has a plurality of blades that give a swirl to the mixed fluid, and is installed at two positions apart from the burner axial direction, and the swirling direction of each of the plurality of blade structures is opposite.
The solid fuel burner, wherein the fuel concentrator is configured to be movable along the burner axial direction.
The solid fuel burner according to claim 4, wherein the fuel concentrator is configured so that a deflection angle of at least an upstream blade with respect to the flow direction of the mixed fluid with respect to the burner axial direction can be adjusted.
A shaft portion supporting the blade,
A spraying device that sprays a cleaning gas toward the boundary between the blade and the shaft,
The solid fuel burner according to any one of claims 1 to 5, further comprising:
The spraying device having a spout for ejecting gas in the radial direction from the shaft portion and a gas guide member for guiding gas from the spout to a boundary portion between the blade and the shaft portion.
The solid fuel burner according to claim 6, further comprising: