JPH08219415A - Burner for solid fuel and pulverized coal firing equipment - Google Patents

Abstract

PURPOSE: To provide a burner for solid fuel and a pulverized coal firing equipment, capable of preventing the adhesion of slag to a flame stabilizer as well as cooling and reduced in the discharging concentration of NOx. CONSTITUTION: A bluff-body type flame stabilizer 36 is provided with the configuration of V-shape and the like and is installed so as to be spread from the fore stream side of the mixed flow 22 of pulverized coal and primary air toward the rear stream side of the same. The shape of the flame stabilizer, which is provided with the V-shape and the like, becomes deeper than the depth of a flat plate type internal flame stabilizer in the side of a flame (inside of a furnace) whereby molten slag hardly arrives at the surface of the flame stabilizer whereby the adhesion of slag can be prevented and it becomes effective for the countermeasure against errosion. On the other hand, the cooling of the flame stabilizer 36 is effected by the primary air of about 80 deg.C and the forming of stagnation point can be prevented compared with the flat plate type flame stabilizer while the flame stabilizer is provided with a slanted surface such as V-shape and the like whereby the surface area of the flame stabilizer is larger than the flat plate type (a projected area is the same) and it functions to promote cooling. As a synergistic effect, when the cooling of the flame stabilizer 36 is promoted, the adhesion of slag to the flame stabilizer can be restrained effectively and naturally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulverized coal combustion device,
Particularly, the present invention relates to a solid fuel burner suitable for stable combustion with low NOx combustion.

[0002]

2. Description of the Related Art In a pulverized coal combustion system used in a conventional boiler or the like, a pulverized coal machine (hereinafter referred to as a mill) having a classifier built therein is used to pulverize coal and convey fine powder of a predetermined size or smaller by classification. A combustion system that directly supplies the burner section with commercial air has been put to practical use.

A two-stage combustion method is typical as a technique for reducing NOx in the pulverized coal combustion system. This two-stage combustion method has an external type and an internal type. The external type is a fuel-rich condition in which the air ratio in the burner zone of the combustion furnace (the ratio of required air to fuel is 1 is a stoichiometric equivalent) is 1 or less. The NOx produced is reduced by reducing the generated NOx by keeping the above value, and the unburned fuel is completely burned by injecting air from the air inlet provided in the downstream of the burner zone. The internal two-stage combustion method swirls the secondary and tertiary air to delay mixing with the pulverized coal flow that is ignited and burned only by the primary air to perform two-stage combustion in the burner zone. It is a method, and it is put to practical use in pulverized coal low NOx burners such as NR and NR2.

[0004]

Due to the low NOx technology using both the external and internal two-stage combustion methods mentioned above, the NOx emission amount at the boiler outlet is around 100 to 150 ppm (fuel ratio = fixed carbon / volatile matter value). 2. Standard coal with N content of 1.5% in coal can reduce unburned content in ash to 5% or less). However, while the regulation of the NOx emission amount contained in the combustion exhaust gas becomes strict as an environmental measure, the NOx emission concentration at the boiler outlet is required to be a low value of 100 ppm or less. In addition to this, in Japan, where the dependence on coal imports is close to 100%, it is essential to establish stable NOx reduction technology regardless of coal type.

Low N for NOx emissions of 100 ppm or less
Various methods have been proposed as measures against Ox. But,
For example, the gas temperature at the burner outlet becomes higher by strengthening the flame holding for lowering NOx, which causes a new problem that the conventional pulverized coal burner does not have. That is, when the burner outlet atmosphere temperature becomes higher, the feedback of heat to the internal flame stabilizer due to radiation is also large, and there is a risk of burning the internal flame stabilizer. Moreover, when the internal flame stabilizer is installed on the concentrated flow side of the burner having a concentrating mechanism, pulverized coal is often entrained and the possibility of slag adhesion increases. If a flat bluff body shape having a flat plate in the direction orthogonal to the fuel flow is used as the outer peripheral flame stabilizer, the outer peripheral flame stabilizer is liable to suffer from erosion due to adhesion of high temperature slag, resulting in poor durability. There is a risk of burning due to insufficient cooling due to the formation of a stagnation point on the upstream side of the flame plate.

An object of the present invention is to provide a solid fuel burner capable of effectively preventing slag from adhering to a flame stabilizer and cooling it. Another object of the present invention is to provide a pulverized coal combustion apparatus which has a low NOx emission concentration while preventing the removal of combustion ash near the burner or the slag adhesion over a wide area of the furnace wall.

[0007]

The above objects of the present invention can be achieved by the following constitutions. That is, in a solid fuel burner having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows and a flame stabilizer at the furnace-side outlet of the solid-gas two-phase flow path, It is a burner for solid fuel in which the shape of a flame stabilizer provided in a gas-two-phase flow channel is widened toward the downstream side from the upstream side of the gas-two-phase flow channel.

Further, according to the present invention, there is provided a burner for a solid fuel having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows. A solid-state solid concentration concentrator is provided, and an outer peripheral flame stabilizer is provided at the outer peripheral portion of the outlet side on the furnace side of the wall surface forming the solid-gas two-phase flow passage, and the solid-gas two-phase flow inside the wall surface. An internal flame stabilizer is provided on each of the solid-concentration concentrated flow sides of the solid-gas two-phase flow formed in the passage, and the shape of the internal flame stabilizer is changed from the upstream side to the downstream side of the flow path of the solid-gas two-phase flow. It is a burner for solid fuel that is widened toward the end.

Furthermore, the present invention provides a solid fuel burner having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows. A solid concentration concentrating device for the phase flow and a solid-gas two-phase flow channel are provided with a partition part for separating the solid concentration concentrated flow and the dilute flow, and a flame stabilizer is provided at the exit side of the partition part on the furnace side. A burner for a solid fuel, in which the flame stabilizer has a shape widening toward the downstream side from the upstream side of the flow path of the solid-gas two-phase flow.

Further, according to the present invention, there is provided a burner for a solid fuel having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transportation gas flows. A partitioning section for separating the solid-flow solid concentration concentrator and the solid-gas two-phase flow channel into a concentrated solid-concentration flow and a dilute flow is provided. A flame stabilizer is provided at the furnace-side outlet of the solid-gas two-phase flow channel in which the concentrated flow is formed, and the shape of the flame stabilizer is directed from the upstream side to the downstream side of the solid-gas two-phase flow channel. It is a burner for solid fuel that is spread out toward the end.

Further, according to the present invention, solid fuel such as coal pulverized by a mill is pulverized into pulverized coal and coarse coal, respectively, and a solid-gas two-phase flow composed of each pulverized solid fuel and transportation gas is produced. In a solid fuel burner having a flow passage, a partition portion that divides into a flow passage containing pulverized coal and a flow passage containing coarse coal is provided in the solid-gas two-phase flow passage, and the furnace side of the partition portion. Is a burner for solid fuel in which a flame stabilizer is provided at an outlet portion of the flame retarder, and the shape of the flame stabilizer is widened toward the downstream side from the upstream side of the flow path of the solid-gas two-phase flow.

The flared shape of the flame stabilizer of the present invention may be U-shaped, V-shaped, U-shaped or semicircular in cross section.

A pulverized coal combustion apparatus equipped with any one of the above solid fuel burners is also within the scope of the present invention.

[0014]

The object of the present invention is to prevent the slag from adhering and cool the flame stabilizer. The shape of the flame stabilizer of the burner for solid fuel of the present invention is deeper than that of the flat plate type internal flame stabilizer on the flame side (inside the furnace), and it is difficult for molten slag to reach the flame stabilizer surface, resulting in slag adhesion. It can prevent and is useful for erosion countermeasures.

Next, the flame stabilizer is cooled with primary air at about 80 ° C. However, in the flat plate type, a stagnation point is formed on the upstream side of the flow, and the cooling becomes insufficient and burns out. there is a possibility. However, if the flame stabilizer has a V-shaped divergent shape from the upstream side to the downstream side with respect to the mixed flow of solid fuel and primary air, the formation of a stagnation point can be prevented and at the same time, the sloped surface of the V-shaped type can prevent The flame surface area (projected area is the same) is also large,
It has the effect of promoting cooling. As a synergistic effect, if the flame stabilizer cools, it naturally helps prevent slag from adhering.

Here, the method for determining the opening angle of the V-shaped configuration will be described, assuming that the flame stabilizer of the present invention is a V-shaped flame stabilizer. In general, the amount of radiant heat from the burner outlet combustion gas to the flame stabilizer (gas temperature T
₍ proportional to the fourth power of _g ) and the heat loss to the primary air are in a steady state and have a proportional relationship, and the heat loss to the primary air is the difference between the flame stabilizer temperature T _s and the primary air temperature T _o. , Which corresponds to the product of the area A of the flame stabilizer and the heat transfer coefficient h, the following equation (1) is established. T _g ⁴ ∝Ah (T _s −T _o ) (1) In the flat flame stabilizer, the gas temperature T _g is T _g1 and the flame stabilizer temperature T _s is T _s1 , and there is no risk of burnout at this temperature. And

Now, _assuming that the gas temperature becomes T _g2 and the flame stabilizer temperature rises to T _s2 by strengthening the flame _stabilizer , the relationship at that time is expressed by the following equation (2). (T _s2 −T _o ) / (T _s1 −T _o ) = (T _g2 / T _g1 ) ⁴ (2) At this temperature of T _s2 , there is a concern that the flame stabilizer will burn out. It is necessary to increase the area and lower it to the safe temperature of T _s1 .

The flame stabilizer area A ₂ (or the opening angle θ of the V type) free from the risk of burning is calculated by the following equation (3). _{A 1 / A 2 = sinθ /} 2 = (T s1 -T o) / (T s2 -T o) (3) where the heat transfer coefficient h for simplification was constant. The right side (T _s1 −T _o ) / (T _s2 −T _o ) of the equation (3) represents the degree of cooling, and the relationship with the V-shaped opening angle θ of the flame stabilizer is shown in FIG. The smaller the value on the vertical axis, the higher the cooling effect,
The cooling effect becomes larger when θ is smaller than that of the flat plate (θ = 180). An example of specifically obtaining θ will be shown. If the safe temperature T _s1 (depending on the material) against the flame stabilizer burnout and the ultimate temperature T _s2 of the flat flame _stabilizer are known, the opening angle θ can be obtained from the equation (3). If T _s1 = 900 ° C, T _s2 = 1000 ° C
Then, θ = 2 sin ⁻¹ [(900-80) / (1000-8
0)] = 126 degrees.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 4 shows a system diagram of a pulverized coal burning boiler to which the burner of this embodiment is applied. Fuel coal is temporarily stored in a coal bunker 1 and then processed into pulverized coal by a mill 2. On the other hand, the primary air that conveys this pulverized coal to the burner 4 in the wind box 3 is PAF.
After being pressurized by the (Primary Air Fan) 5, it is heat-exchanged with the high temperature boiler combustion exhaust gas by the heat exchanger 6 provided at the boiler outlet portion, heated to about 300 ° C., and then sent to the mill 2. . The temperature-elevating air is sent to the burner 4 together with the pulverized coal after evaporating the water adhering to the coal inside the mill 2. The primary air temperature at the burner 4 inlet is about 8
It drops to 0 ° C.

When pulverized coal having a relatively coarse grain size and pulverized coal having a relatively fine grain size are used in combination, the pulverized coal is processed into a relatively coarse grain size in the mill 2 and conveyed to the burner 4 by heated air. At the same time, the coal pulverized into a relatively fine particle size is supplied from the pulverized coal mill 9 to the burner 4 via the bottle 10, the feeder 11 and the pulverized coal entraining device 12. The pulverized coal pulverized to have a relatively fine particle size is also conveyed to the burner 4 by the air whose temperature is raised to about 300 ° C. by the heat exchanger 6.

Combustion air such as secondary air and tertiary air is heated by a heat exchanger 1 by an FDF (Forced Draft Fan) 14.
It is supplied to the wind box 3 in which the burner 4 is arranged via 5 Further, high temperature air for combustion remains in a part of the boiler exhaust gas and is supplied to the bottom of the boiler furnace 17 by a GRF (exhaust gas mixing fan) 16 and also the exhaust gas mixing device 1
It is mixed with the primary air whose temperature is raised in the heat exchanger 6 in 9 and is also supplied to the pulverized coal entraining device 12.

FIG. 1 is a sectional view (FIG. 1 (a)) and a front view (FIG. 1 (b) of a burner in which a ring-shaped V-type internal flame stabilizer is additionally provided to the low NOx burner (NR burner) of this embodiment. )) Is shown, the upper half of which is not shown. A starter burner 21 that uses heavy oil as a fuel is installed in the central portion of the burner, and a primary flow path 23 through which a mixed flow 22 of primary air and pulverized coal flows is provided around it. Further, a circular flow path is provided around the flow path 26 for the secondary air 25 and a flow path 29 for the tertiary air 28 in that order. The swirling of the air flow in the secondary air flow path 26 and the tertiary air flow path 29 depends on the flow paths 26, 2 respectively.
Register damper 3 provided as a swivel function in 9
Perform at 0 and 31. Therefore, the secondary air 25 and the tertiary air 28 are swirled by the register dampers 30 and 31,
It is fed into the wall 32 of the furnace. A secondary air swirl vane 34 for swirling flow formation is provided at the outlet of the secondary air flow path 26 in the furnace.

The burner shown in FIG. 1 is characterized in that a V-type internal flame stabilizer 36 is provided in addition to the outer peripheral flame stabilizer 35 provided on the outer periphery of the primary air passage 23 for mixing primary air and pulverized coal at the burner outlet. Two
This is a point that the internal combustion chamber 3 has inside, and the V-type internal flame stabilizer 36 strengthens flame holding at the burner outlet, and the secondary air 25
The NOx can be reduced by expanding the reduction region by delaying the mixing of the peripheral air due to the strong swirling of the tertiary air 28.

The mixed flow 22 of primary air and pulverized coal, which is conveyed by the primary air for combustion from the mills 2 and 9 (FIG. 4), is sent to the primary flow path 23, and the temperature of the primary air at this time is The temperature is about 80 ° C., which also contributes to cooling the internal flame stabilizer 36.

FIG. 2 shows the low NOx of the second embodiment of the present invention.
Shows a burner and has a low NOx burner (NR
V-type flame stabilizer 36 is installed in the 2 burners). In addition,
Regarding other members, members having the same functions as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. The feature of this embodiment is that the internal concentrator 37 is provided in the primary passage 23 through which the mixed flow 22 of primary air and pulverized coal flows so as to narrow the cross-sectional area of the primary passage 23. The V-shaped flame stabilizer 36 is installed at a position surrounded by the concentrated flow on the outer peripheral side of the primary flow path 23 formed by the internal concentrator 37, and its shape is the same as that of FIG. It is a V-shaped ring.

FIG. 3 shows the low NO of the third embodiment of the present invention.
A cross-sectional view of an x burner is shown, showing an example in which a V-type internal flame stabilizer is provided in a low NOx burner that is dividedly supplied into fine powder and coarse powder. In FIG. 3, members having the same functions as those shown in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. The pulverized coal having a relatively small particle size and the air mixed flow 22a described in FIG.
A pipe 38 that conveys the air and a pipe 39 through which the pulverized coal having a relatively coarse grain size and the air mixed flow 22b pass are installed around the pipe 38. A ring-shaped V-shaped internal flame stabilizer 36 is installed at the end of the pipe 38 on the boiler furnace side.

In FIG. 3, a burner for separately supplying pulverized coal to pulverized coal (inner side) and coarse grained coal (outer side) is shown. However, although not shown, pulverized coal is the outside of the burner and the coarse grained coal. May be a burner in which a V-type flame stabilizer is installed inside the burner at the burner outlet of the separating partition.

As described with reference to FIG. 4, the primary air temperature when it exits the mill 2 (FIG. 1) is about 80 ° C., and it is sent into the primary flow path 23 together with the pulverized coal, and each of the above-mentioned present inventions. Useful for cooling the V-shaped internal flame stabilizer 36 of the embodiment.

When the flat type internal flame stabilizer of the prior art is added to the pulverized coal burner shown in FIG. 4, the burner outlet atmosphere temperature becomes higher. Therefore, the feedback of heat to the flat plate internal flame stabilizer due to radiation is also large, and there is a risk of burning the flat plate internal flame stabilizer. Moreover, the internal concentrator 3 of FIG.
When an internal flame stabilizer is installed on the concentrated flow side of a burner having a concentrating mechanism such as No. 7, pulverized coal is often entrained and the risk of slag adhesion increases. Therefore, the contact area of the V-shaped flame stabilizer is larger than that of the flat-plate bluff body shape having a plane in a direction orthogonal to the pulverized coal and air mixed flow 22 used as the outer peripheral flame stabilizer, and the cooling effect is enhanced. be able to.

In the embodiment of the present invention shown in FIGS. 1 to 3, the burner having the V-shaped outer peripheral flame stabilizer 36 in the primary flow path 23 is taken as an example, but in FIG. Another example of the burner is shown in FIGS. 1 to 3 in which only the internal flame stabilizer 36 without the outer flame stabilizer 35 is provided in the primary flow path 23. The burner shown in FIG. 5 (FIG. 5A is a cross-sectional view and FIG. 5B is a front view seen from the furnace side) has a V-shaped ring-shaped internal flame stabilizer 36 in the primary flow path 23. The pulverized coal stream (mixed stream 22 of pulverized coal and air) conveyed by combustion air from the mill 2 is sent to the primary flow path 23. At this time, the temperature of the carrier air (primary air) is about 80 ° C., which has the function of cooling the V-shaped internal flame stabilizer 36.

In the embodiment shown in FIG. 2, the V-shaped internal flame stabilizer 36 is installed in the burner having a concentrating function, but although not shown, the V-shaped internal flame stabilizer 36 is conveyed while swirling to the burner portion. A burner having a concentrating function that utilizes the difference in inertial force between the solid particles and the gas, with a V-type flame stabilizer installed at the position where it is surrounded by the concentrated flow or at the boundary between the concentrated flow and the lean flow. It is within the scope of the present invention.

Further, as another embodiment of the burner with a concentrating function, a pulverized coal burner other than a cylindrical type for a boiler furnace is also within the scope of the present invention, and the shape of the bluff body installed at the furnace outlet of the burner. There is a problem of burnout and adhesion of high temperature slag even with the flame stabilizer. Although the embodiment shown in FIGS. 6 and 7 shows a solid fuel burner having a square section cross-section and having a concentration function, a bluff body-shaped flame stabilizer installed therein also
The V type can be used to solve the problems of burnout and high temperature slag adhesion. FIG. 6 shows an example in which a partition plate 41 for partitioning the concentrated flow 22c and the lean flow 22d of the mixed flow 22 of pulverized coal and air is installed in the primary flow path 23, and the V-shaped flame stabilizer 40 is installed on the partition plate 41. (FIG. 6 (a) is a cross-sectional view of the primary flow path 23 of the burner, FIG. 6 (b) is a view of the primary flow path 23 of the burner as seen from the boiler furnace side), and FIG.
3 is provided with a partition plate 41 for partitioning the concentrated flow 22c of the pulverized coal / air mixed flow 22 and the lean flow 22d.
An example in which the V-type flame stabilizer 40 is installed only on the side is shown (FIG. 7).
7A is a cross-sectional view of the primary flow passage 23 of the burner, FIG. 7B is a view of the primary flow passage 23 of the burner seen from the boiler furnace side, FIG.
(C) is a view taken along the line AA of FIG. 7 (a). Further, in addition to the V-shaped V-shaped flame stabilizers 36 and 40, a V-shaped flame stabilizer 36, 40 having a U-shaped cross section, a U-shaped shape, a semi-circular shape, or the like may be used as shown in FIG.

[0033]

According to the ultra-low NOx pulverized coal combustion apparatus of the present invention, the ultra-low NOx reduction in the burner portion, which cannot be achieved by the ordinary pulverized coal burner, causes burnout of the internal flame stabilizer and the internal flame holding. It is possible without adhering slag to the vessel, and it is possible to reduce the ammonia consumption in the denitration device.

[Brief description of drawings]

FIG. 1 is a sectional view and a front view of an ultra-low NOx burner additionally provided with a V-type internal flame stabilizer according to an embodiment of the present invention.

FIG. 2 is a sectional view of a concentrated functional low NOx burner additionally provided with a V-type internal flame stabilizer according to an embodiment of the present invention.

FIG. 3 is a sectional view of a burner in which a V-shaped internal flame stabilizer-equipped fine powder conveying pipe according to an embodiment of the present invention is installed.

FIG. 4 is a system diagram of a pulverized coal combustion apparatus according to an embodiment of the present invention.

FIG. 5: Low N with V-type internal flame stabilizer according to one embodiment of the present invention
It is sectional drawing and front view of an Ox burner.

6A and 6B are a sectional view and a front view in which the burner with a concentrating function of one embodiment of the present invention is divided into a concentrated flow and a lean flow.

FIG. 7 is a sectional view, a front view, and a partial cutaway view of a burner in which a V-type flame stabilizer is installed on the concentrate flow side of a burner with a concentration function according to an embodiment of the present invention.

FIG. 8 is a view showing a sectional shape of a flame stabilizer according to an embodiment of the present invention.

FIG. 9 is a diagram showing a cooling effect of a V-shaped opening angle of a flame stabilizer according to an embodiment of the present invention.

[Explanation of symbols]

21 ... Start-up burner, 22 ... Mixed flow of primary air and pulverized coal, 23 ... Primary flow path, 25 ... Secondary air, 26 ... Secondary air flow path, 28 ... Tertiary air, 29 ... Tertiary air flow path, 30 Three
DESCRIPTION OF SYMBOLS 1 ... Register damper, 32 ... Furnace wall surface, 34 ... Secondary air swirling vane, 35 ... Peripheral flame stabilizer, 36, 40 ... V type internal flame stabilizer, 37 ... Internal concentrator, 38, 39 ... Pulverized coal and air Mixed flow transport pipe, 41 ... Partition plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Noboru Miyama, No. 36 Takaracho, Kure City, Hiroshima Prefecture Babcock-Hitachi Co., Ltd., Kure Research Institute (72) Shigeki Morita, 6-9 Takaramachi, Kure City, Hiroshima Prefecture Babcock-Hitachi Stock Company Kure Factory

Claims (7)

[Claims] 1. A burner for solid fuel having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows, and a flame stabilizer at the furnace-side outlet of the solid-gas two-phase flow path. In the above, the burner for solid fuel is characterized in that the shape of the flame stabilizer provided in the flow path of the solid-gas two-phase flow is widened toward the downstream side from the upstream side of the flow path of the solid-gas two-phase flow. . 2. A solid fuel burner having a flow path in which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows, wherein a solid-gas two-phase flow is formed in the solid-gas two-phase flow path. A solid concentration concentrator is provided, and an outer peripheral flame stabilizer is provided at the outer peripheral portion of the outlet portion on the furnace side of the wall surface forming the solid-gas two-phase flow passage, and the solid-gas two-phase flow passage is formed inside the wall surface. Internal flame stabilizers are respectively provided on the solid-concentration-concentrated streams side of the solid-gas two-phase flow to be formed, and the shapes of the internal flame stabilizers spread from the upstream side to the downstream side of the flow path of the solid-gas two-phase flow. A burner for a solid fuel, which is characterized by being formed into a shape. 3. A solid fuel burner having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows, wherein a solid-gas two-phase flow is formed in the solid-gas two-phase flow path. A solid concentration concentrator and a solid-gas two-phase flow channel are provided with a partition for separating the solid concentration concentrated flow and the dilute flow, and a flame stabilizer is provided at the furnace-side outlet of the partition. A burner for a solid fuel, characterized in that the shape of the flame is expanded toward the downstream side from the upstream side of the flow path of the solid-gas two-phase flow. 4. A solid fuel burner having a flow path through which a solid-gas two-phase flow composed of a solid fuel such as coal and a transport gas flows, wherein a solid-gas two-phase flow of the solid-gas two-phase flow is formed in the flow path of the solid-gas two-phase flow. A partitioning portion for separating the solid concentration concentrating device and the solid-gas two-phase flow channel into a solid concentration concentrated flow and a dilute flow is provided, and the solid concentration concentrated flow in the solid-gas two-phase flow channel is A flame stabilizer is provided at the furnace-side outlet of the solid-gas two-phase flow channel to be formed, and the shape of the flame stabilizer is widened from the upstream side to the downstream side of the solid-gas two-phase flow channel. A burner for solid fuel, characterized in that 5. A flow path through which a solid fuel such as coal pulverized by a mill is pulverized into pulverized coal and pulverized coal, respectively, and a solid-gas two-phase flow composed of the pulverized solid fuel and the transport gas flows. In a burner for solid fuel having a solid-gas two-phase flow channel, a partition section that divides into a channel containing pulverized coal and a channel containing coarse coal is provided at the furnace-side outlet of the partition section. A burner for a solid fuel, wherein a flame stabilizer is provided in the burner, and the shape of the flame stabilizer is widened toward the downstream side from the upstream side of the flow path of the solid-gas two-phase flow. 6. The flame spreader has a U-shaped cross section and a V-shaped cross section.
The burner for solid fuel according to any one of claims 1 to 5, which has a mold shape, a U-shape, or a semicircular shape. 7. A pulverized coal combustion apparatus comprising the burner for solid fuel according to any one of claims 1 to 6.