JPH0229924B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial Application Field The present invention is applicable to heat sources for industrial furnaces in a broad sense, including heat sources for furnaces such as heat treatment furnaces and boilers, as well as heat sources for dryers, heat exchangers, etc. The present invention relates to a burner device for powdery solid fuel that is particularly useful for supplying high-temperature combustion gas or flame produced by burning powdery solid fuel in a burner to an industrial furnace. (b) Prior art and (c) Problems in the technology to be solved by the present invention. Conventionally, in combustion equipment for granular solid fuels such as pulverized coal, it is common to blow pulverized coal that has been pulverized in advance directly into the furnace using primary air. Various improvements have been proposed, but it is difficult to obtain satisfactory results, such as the occurrence of abnormally overheated parts,
It is practically impossible to avoid problems such as the formation of clinker lumps, adhesion to the furnace wall, and furnace wall burnout.Furthermore, the combustion gas or flame that is formed is far from a completely burnt clean state, such as heat treatment. The reality is that it is practically impossible to avoid contamination of the materials to be processed in the furnace and occurrence of loss. Furthermore, there is a proposal for a sawdust combustion device disclosed in Japanese Patent Application Laid-open No. 53034/1983, which uses sawdust as a powdery solid fuel. In this proposal, the sawdust entrained in the primary air is passed through an overflow cylinder having one secondary air jet port to the lower part of the inlet side of the secondary combustion chamber having the ignition port, that is, the secondary Blow into the secondary combustion chamber at a non-coaxial position where the longitudinal center axis of the overflow tube is significantly deviated downward from the longitudinal center axis of the combustion chamber, and One narrow groove-shaped tertiary air outlet having a length approximately equal to the length of unburned particles that fall and accumulate at the bottom of the secondary combustion chamber is installed at the bottom of the secondary combustion chamber. A sawdust combustion device has been proposed that is installed along the length of the chamber and is designed to burn unburned sawdust that accumulates at the bottom along the furnace wall of the secondary combustion chamber. This proposal states that hot air with no smoke or ash visible to the naked eye is ejected from the hot air discharge port on the outlet side of the secondary combustion chamber, but according to the inventor's study, the sawdust of this proposal Depending on the combustion equipment, it is completely impossible to produce completely combusted combustion gas or a flame in a clean state. Furthermore, abnormally overheated areas may occur, clinker lumps may form, and they may stick to the furnace wall.
It was found that problems such as furnace wall burnout, contamination of processed materials, and loss could not be avoided. (d) Means to solve the problem, (e) action and (f)
Summary of effects. The present inventor has conducted research to develop a burner device for powdery solid fuel that can overcome the technical problems of the prior art as described above. As a result, a primary combustion zone is connected to the primary combustion zone having a plurality of secondary air supply nozzles arranged to form a swirling flow of secondary combustion air that travels in the direction of the combustion outlet within the combustion zone. a secondary combustion zone having a plurality of tertiary air supply nozzles arranged to form a similar swirling flow of tertiary combustion air, and directed to the secondary combustion zone provided at the connection part; By providing a structural feature that satisfies the combination of the three requirements of the flame length adjustment air supply port, the technical problems described above (problems of the prior art) can be advantageously overcome; It has now been discovered that a significantly superior burner system for granular solid fuels can be provided with a number of new benefits. According to the research of the present inventor, by creating a burner device for granular solid fuel that has structural features that satisfy the combination of the above three requirements, it is possible to prevent the occurrence of abnormally overheated areas in the combustion zone. While forming and maintaining a floating swirling state of the solid combustion that can be skillfully and reliably avoided and suppressed sedimentation and accumulation of the powdery solid fuel, complete combustion of the powdery solid fuel can be achieved with an appropriate floating residence time. It has been found that gasification and combustion can be carried out efficiently. Furthermore, because the above-mentioned effects are produced by the structural features that satisfy the above-mentioned bonding requirements, there is no risk of clinker agglomeration formation, and even if clinker formation occurs, the amount is significantly reduced. It has also been found that it can be formed in a very finely divided manner without any trouble and is also advantageously freed from the deficiencies of the prior art, such as sticking to the inner wall of the combustion zone and burnout of the furnace wall. Furthermore, by providing a burner device with structural features that satisfy the above-mentioned coupling requirements, the high-temperature combustion gas or flame that is formed can be sent into industrial furnaces in a completely combusted and clean state. It is advantageously freed from troubles such as contamination and loss of the processed materials in the furnace, and can be used, for example, as a burner device for granular solid fuel for supplying high-temperature combustion gas or flame to a heating annealing treatment furnace for steel. In some cases,
The generation of scale (iron oxide) is about 1/1 that of conventional furnaces.
It has been found that it is possible to significantly improve the product yield by significantly reducing the amount to about 3%. Furthermore, because of the above structural features, it is possible to feed a thick high-temperature combustion gas or flame stream into industrial furnaces, and to adjust the flame length (high-temperature combustion gas or flame stream directly reaches the interior of the industrial furnace). This makes it possible to easily and reliably adjust the temperature distribution in the furnace, thereby achieving a high level of uniformity in the temperature distribution within the furnace, as well as adjusting the arrangement of the objects to be treated in industrial furnaces and the heat treatment temperature. It is now possible to adjust the time and time with efficiency comparable to that of an electric furnace.
It has been found that advantages can also be obtained, such as the ability to move the workpiece into and out of the furnace without the need to interrupt operation. Furthermore, since it has the above-mentioned structural characteristics, it is possible to advantageously use cheap granular wood solid combustion as the granular solid fuel, and furthermore, the combustion efficiency is significantly improved, compared to, for example, the use of A heavy oil fuel. About 50~
It is possible to reduce costs by a significantly reduced fuel ratio of about 60% compared to the use of LPG fuel, and about 25 to 35% compared to the use of city gas fuel. For example, it can be designed to be a movable structure that can be moved on rails, the primary combustion zone and the secondary combustion zone can be designed to be a detachable connection structure, and the The supply of granular solid fuel, the supply of air for secondary combustion, the supply of air for tertiary combustion, the supply of flame length adjustment air, etc. are carried out in the primary combustion area, secondary combustion area, and even in industrial furnaces. It has been found that the above-mentioned technical problems in the conventional technology can be solved all at once, with many benefits such as the ability to easily control the temperature using an automatic adjustment mechanism linked to temperature detection. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a burner device for granular solid fuel that can achieve various improved effects. The above objects and many other objects and advantages of the present invention will become more apparent from the following description. (d) Means for solving the problem, (e) action, (f) effect, and (g) details of examples. Hereinafter, in order to facilitate understanding, the burner device for powdery solid fuel of the present invention will be explained using the accompanying drawings. FIG. 1 is a cross-sectional view of a typical example of the burner device of the present invention, and FIG. 2 is a cross-sectional view of the primary combustion zone in a direction perpendicular to the cross-sectional view of FIG. 1. FIG. 3 is a sectional view showing an example of the connection between the granular solid fuel storage tank and the primary combustion zone of the burner device of the present invention. In FIG. 1, the burner device for powdery solid fuel of the present invention has a fuel supply port 3 for supplying powdery solid fuel accompanied by primary combustion air and an ignition means 4 for igniting the fuel at one end. a primary combustion zone 1 having a primary combustion outlet 5 at the other end; a swirling flow of secondary combustion air provided on the side wall of the primary combustion zone and proceeding in the direction of the primary combustion outlet 5; a plurality of secondary air supply nozzles 6, 6... arranged to form a A secondary combustion zone 2 having a flow outlet 7, and a secondary combustion zone provided on a side wall of the secondary combustion zone and arranged to form a swirling flow of tertiary combustion air traveling in the direction of the secondary combustion flow outlet 7. and a plurality of tertiary air supply nozzles 8, 8, . It has a structure in which a length adjusting air supply port 9 is provided. The inner wall constituting the primary combustion zone 1 is made of refractory material 1
A plurality of secondary air supply nozzles 6, 6 . arranged to form a In the example of FIG. 1, the secondary combustion air is introduced into the secondary air supply nozzles 6, 6 through a secondary air jacket 10 provided around the outer periphery of the primary combustion zone 1. An example is shown in which the water is supplied from the supply port 11. The design of introducing the secondary combustion air into the secondary air supply nozzles 6, 6 can be changed to any other means, for example, a so-called "manifold" having branch pipes connected from the header to each nozzle. It is also possible to change the design to a different type, or to install such a manifold type secondary combustion air introduction passage buried in the 12 layers of refractory material. As shown in FIG. 2 in a cross-sectional view in a direction perpendicular to the cross-sectional view in FIG. 1, in this example, four series of secondary air supply nozzles 6, 6... are arranged so as to send out secondary combustion air in the direction along the inner circumferential wall of area 1, as well shown in FIG. 2, and as well shown in FIG. 1, These nozzles 6, 6, . . . are arranged as passages inclined toward the primary combustion outlet 5. In this way, a swirling flow of secondary combustion air can be formed within the primary combustion zone 1 that advances in the direction of the primary combustion outlet 5. The number of nozzles 6, 6..., arrangement series, direction of introduction into zone 1, inclination, etc. can be appropriately selected as long as a swirling flow of secondary combustion air traveling toward the primary combustion outlet 5 can be formed. This is within a range that can be easily modified by a person skilled in the art. In addition, in the example of Fig. 1, the primary combustion zone 1
Of the walls that make up the area, the part indicated by 12' in the figure is
It is shown in an embodiment composed of an openable and closable inlet door body 12' equipped with a fuel supply port 3 for supplying granular solid fuel accompanied by primary combustion air and ignition means 4 for igniting the fuel. However, any other embodiment may be adopted. In the example of FIG. 1, the secondary combustion zone 2 is shown having an inlet portion connected to the outlet 5 of the primary combustion zone 1 at one end and a primary combustion outlet 7 at the other end. There is. Tertiary air supply nozzle 8, 8...
are arranged to form a swirling flow of tertiary combustion air proceeding in the direction of the secondary combustion outlet 7, in the same manner as described above for the primary combustion zone 1, and are arranged to form a swirling flow of tertiary combustion air proceeding in the direction of the secondary combustion outlet 7, and are routed through the tertiary air jacket 10. Supply port 11
The tertiary combustion air supplied from the tertiary combustion air is designed to form a swirling flow of tertiary combustion air in the direction of the secondary combustion outlet 7 in the secondary combustion zone 2. The secondary combustion zone 2 is further provided with a flame length adjusting air supply port 9 directed toward the secondary combustion zone 2 at the connection between the primary combustion zone 1 and the secondary combustion zone 2. . In the example shown in the figure, an annular gap is formed between the inner wall surface made of the refractory material 12 constituting the secondary combustion zone 2 and the outer peripheral surface of the primary combustion outlet 5 of the primary combustion zone 1. is the secondary combustion zone 2
The example shown is one designed to open toward the Air supplied from 9' in the figure is introduced into the secondary combustion zone 2 from the flame length adjusting air supply port 9 through the annular gap. The flame length adjustment air supply port is not limited to the above embodiment, and flame length adjustment air can be supplied toward the secondary combustion area at the connection between the primary combustion area 1 and the secondary combustion area 2. The design can be changed to any other structure. For example, a flange may be provided that fills the annular gap, and a plurality of holes may be bored on the flange surface at desired appropriate intervals through which the flame length adjusting air can pass, or alternatively, a flange may be provided that fills the annular space, and a plurality of holes may be bored through the flame length adjusting air at appropriate intervals as desired; The design may be modified so that an annular manifold is buried in the refractory material 12 of the area 1 and air supply ports are provided at appropriate locations in the area 1 to introduce flame length adjustment air toward the secondary combustion area. can. The connection between the primary combustion zone and the secondary combustion zone is
Although it may be non-removably fixed, it is preferable to design it to be removable. For example, it is preferable to design it so that it can be attached and detached using any desired appropriate means such as a fitting method, a bolt-and-nut method, or a clamp method.
In addition, in FIG. 1, A indicates an industrial furnace. The burner device of the present invention can be mounted on a suitable underframe 32 or mounted on suitable moving wheels 1 as desired.
3, 13... can be attached and designed to be movable, which is preferable. At this time, a rail 24 may be provided on the base plate, and a wheel structure may be provided on which the rail 24 can be moved. FIG. 3 shows a partially cut-out primary combustion area having a fuel supply port 3 for supplying powdery solid fuel entrained in the primary combustion air and an ignition means 4 for igniting the fuel, and a powdery solid fuel A sectional view showing an example of connection with a fuel tank is shown. In the figure, 4 is an ignition oil burner, 4' is its nozzle, and 3' is a powder solid fuel disperser. In the embodiment of FIG. 3, the granular solid fuel 21 contained in the storage tank 14 having the granular solid fuel supply port 16 is transferred to the passage 18 by suitable supply means such as a screw feeder 17. Sent out. An example is shown in which the storage tank 14 is provided with a level switch 15 that detects and operates the level of the fuel 21. A blower 20 provided in the passage 18 generates primary combustion air 22.
The fuel 21 is forced through the passage 19 from the fuel supply port 3 into the distributor 3', and is ignited by an ignition means consisting of an ignition oil burner 4 having a nozzle 4' in this example. be burned. The ignition means and the distributor can be and are preferably designed to be removably arranged, for example in a hinged manner. Incidentally, the ignition means is not limited to the above-mentioned embodiment, and can be selected and changed as appropriate.
Instead of the ignition means, for example, a hand-fired ignition means that inputs a pilot flame for ignition may be used. Further, if desired, the design of the blower 20 can be changed to include means for crushing coarse solid fuel. The burner device for powdery solid fuel of the present invention has been described above, and next, one aspect of the operation for supplying high temperature combustion gas or flame to the industrial furnace A using the device will be described. For example, by operating as described for the example in FIG. be done. On this occasion,
For example, by designing the solid fuel to be entrained and pumped along the cylindrical inner peripheral surface of the disperser 3' with the primary combustion air, a cyclone-like swirling flow state is created in the disperser 3'. can do.
In addition, at this time, in order to eliminate the possibility that pulverized fuel that may be contained in granular solid fuel may stick to the inner circumferential surface of the fuel disperser 3', the disperser 3' is provided with an appropriate cooling means such as a cooling jacket. Can be attached. The swirling flow of the ignited solid fuel flows through the primary combustion zone 1.
promotes uniform distribution of fuel introduced into the area 1. This combustion flow of granular solid fuel accompanied by the effect of promoting uniform dispersion is formed in the primary combustion zone 1 by secondary combustion air supplied from a plurality of secondary air supply nozzles 6, 6... Due to the action of the swirling flow of secondary combustion air proceeding in the direction of the primary combustion outlet 5, a very satisfactory primary combustion effect is produced. That is, by forcibly suppressing sedimentation and accumulation of the solid fuel in the area 1, a combustion state of the solid fuel under floating swirling agitation conditions is formed and maintained, and appropriate floating and retention is achieved. Achieve the ideal primary combustion effect over time.
Then, in combination with the effect of the swirling flow of the tertiary combustion air similar to that described above proceeding in the direction of the secondary combustion outlet 7 in the subsequent secondary combustion zone 2, a complete gasification combustion effect of the powdery solid fuel is achieved. This makes it possible to achieve this efficiently. At this time, for example, by appropriately adjusting the amount of secondary combustion air supplied to the primary combustion zone 1,
The total amount of primary combustion air and secondary combustion air can be adjusted to a predetermined suitable desired air supply amount range, so that the combustion temperature in zone 1 can be adjusted depending on, for example, the type of granular solid fuel used. Appropriate conditions for generating combustible decomposed gas can be set depending on the amount and amount of combustible decomposition gas. In addition, in the secondary combustion zone 2,
The supply amount of the tertiary combustion air supplied to the zone 2 is suitably adjusted so that the combustion stream from the zone 1 is in a complete gasification combustion state, and the flame length adjustment air and the air from the zone 1 are combined. The total amount of air can be adjusted to a preset desired range of air supply,
The combustion temperature in zone 1 can thus be set to perfect gasification combustion conditions depending on the state of the primary combustion product. Note that, if desired, the tertiary combustion air can also be supplied in the form of preheated air used for heat exchange, for example, as cooling air. Temperature control in the primary combustion zone 1 and the secondary combustion zone 2 depends on the type of granular solid fuel used;
It can be changed appropriately depending on the amount and other conditions, but
For example, in one example using granular woody solid fuel, the temperature of zone 1 is adjusted to about 600°C to primarily perform flammable decomposition and gasification of the fuel, and the temperature of zone 2 is adjusted to about 1400°C, for example. Complete gasification and combustion temperature of the combustion stream from zone 1 is adjusted to about ℃, and the secondary combustion stream introduced into industrial furnaces is made into a clean, high-temperature combustion gas or flame that is completely combusted. be able to. Furthermore, in the burner device of the present invention, from the flame length adjustment air supply port 9 provided at the connection between the primary combustion zone 1 and the secondary combustion zone 2 and directed toward the zone 2, In other words, an air flow directed in the direction of rotation of the swirling flow in zone 2 is supplied, and by adjusting the pumping conditions, this air flow can be used to transform the high-temperature combustion gas or flame flow obtained by the device of the present invention. It is possible to adjust the area of direct access into industrial furnaces, that is, the flame length, and to easily and reliably carry out the adjustment, and to provide a plurality of secondary air supplies in the first zone. In cooperation with the swirling flow forming action of the nozzles 6, 6... and the plurality of tertiary air supply nozzles 8, 8... in the second zone, which proceed in the direction of the outlet of these zones, the primary combustion zone undergoes secondary combustion. It also serves to promote the formation of the desired and appropriate coaxial swirl flow through the area. Furthermore, in the burner device of the present invention, the primary combustion zone and the secondary combustion zone are connected so as to be located substantially coaxially with respect to the center axis in the direction of movement of the swirling flow formed therein. This is preferred and helps in creating the desired and appropriate coaxial swirl flow, in addition to the design and operational benefits. The burner device for powdery solid fuel of the present invention can be applied to a wide range of powdery solid fuels. For example, pulverized coal, raw ash (charcoal powder), sawdust/wood dust, crushed paper, bitumen powder, and other processed granular solid fuels. Remeltable asphalt powder made by powdering a molten mixture containing asphalts and olefinic resins, and granules thereof, as well as granules made by pelletizing wood flour using the powder as a binder, such as JP-A Akira
Various other types of granular solid fuel can be used, such as the improved solid wood fuel known in US Pat. According to the apparatus of the present invention, as described in detail above, a plurality of secondary air supply nozzles are arranged to form a swirling flow of secondary combustion air that advances toward the combustion outlet within the combustion zone. a secondary combustion zone having a plurality of tertiary air supply nozzles connected thereto and arranged to form a similar swirling flow of tertiary combustion air; Preferably, the primary combustion zone is further provided with a structural feature that satisfies the combination of the three requirements of a flame length adjusting air supply port directed to the secondary combustion zone provided. By creating a structure in which the combustion chamber and the secondary combustion zone are connected so that the center axes in the direction of movement of the swirling flow formed in these zones are located approximately coaxially, many improvements such as the following can be achieved. effect can be achieved. (i) The combustion products gasified in the primary combustion zone move to the secondary combustion zone while combusting and swirling with the secondary combustion air supplied from the secondary air supply nozzle. Even in the secondary combustion zone, the combustible material is combusted by the tertiary combustion air supplied from the tertiary air supply nozzle and moves in the direction of the secondary combustion outlet while floating and swirling.
It is possible to skillfully and reliably avoid the occurrence of abnormally overheated areas in the combustion zone, and to form and maintain a floating swirling agitation state of the solid fuel that suppresses sedimentation and accumulation of the particulate solid fuel, while ensuring appropriate floating retention. It becomes possible to efficiently perform complete gasification and combustion of particulate solid fuel over time. (ii) There is no risk of clinker agglomeration, and even if clinker does form, it is formed in a significantly reduced amount and in an extremely finely divided state without any trouble; The disadvantages of the prior art, such as sticking to the furnace wall and burning out of the furnace wall, are overcome. (iii) Since the high-temperature combustion gas or flame that is formed is sent into the industrial furnace in a completely combusted and clean state, problems such as contamination of the processed materials on the furnace wall and loss generation are advantageously avoided. For example, when used as a burner device for granular solid fuel to supply high-temperature combustion gas or flame to a heating annealing processing furnace for steel, scale (iron oxide) generation is reduced to about 1/3 of that of conventional furnaces. It is possible to obtain the benefit of significantly improving the product yield by significantly reducing the amount of water. (iv) It becomes possible to feed into industrial furnaces in the form of a thick high-temperature combustion gas or flame stream, and it is possible to adjust the flame length (adjust the area where the high-temperature combustion gas or flame stream directly reaches the interior of the industrial furnaces). This makes it possible to easily and reliably perform the process, thus achieving a high level of uniformity in the temperature distribution within the furnace, and controlling the arrangement of objects to be treated and the heat treatment temperature and time in industrial furnaces. It becomes possible to carry out the process with an efficiency comparable to that of the furnace, and there are also advantages such as being able to take the workpieces in and out of the furnace without having to interrupt the operation. Furthermore, the apparatus of the present invention provides a flame length adjusting air supply port directed to the secondary combustion zone at the connection between the primary combustion zone and the secondary combustion zone, thereby controlling the combustion air. Flame control can be performed separately from the flame control by . Flame Length Adjustment The ability to adjust the length of the flame using the air supply port is useful, for example, when using a burner device in a special furnace where the direction of heat flow is regulated, when drying sand, etc., or when using a direct flame such as in an incinerator. This is extremely convenient when making contact. In addition, the air flow supplied from the flame length adjustment air supply port cooperates with the swirl flow forming action of the secondary air supply nozzle and the tertiary air supply nozzle, so that the primary combustion zone passes through the secondary combustion zone to the desired position. It also helps to foster proper coaxial swirl flow formation. (v) Cheap powdery solid wood fuel can be advantageously used as the powdery solid fuel, and the combustion efficiency is significantly improved, for example, by about 50 to 60% compared to the use of A heavy oil fuel. It is possible to reduce costs by significantly reducing the fuel ratio by about 60% compared to the use of LPG fuel and about 25 to 35% compared to the use of city gas fuel. (vi) The device may be designed as a mobile structure, for example movable on rails, and may be designed as a removable connection structure between the primary combustion zone and the secondary combustion zone, and may also be designed to have a removable connection between the primary combustion zone and the secondary combustion zone, and may also be designed to have a removable connection between the primary and secondary combustion zones. The supply of granular solid fuel accompanying the combustion, the supply of air for secondary combustion, the supply of air for tertiary combustion, the supply of flame length adjustment air, etc. It can be easily controlled using an automatic adjustment mechanism linked to temperature detection in furnaces, etc., such as a PID control system. An example using the device of the present invention will be described below. Examples 1 to 3 and Comparative Example 1 The apparatus of the present invention shown in FIGS. 1 to 3 was attached to a heating furnace for solution treatment (annealing) of stainless steel castings, and the solution treatment was performed. As particulate solid fuel, the following three types of fuel No. 1 ~
The results obtained using No. 3 are shown in Table 1 below. For comparison, Table 1 also shows the results of solution treatment using a similar heating furnace equipped with a kerosene combustion burner device. Fuel No. 1 Pellet fuel made by pelletizing wood flour using remeltable asphalt powder obtained in Japanese Patent Publication No. 59-12712 as a binder. Fuel No. 2: Crushed waste plywood for wooden building materials. Fuel No. 3 Pellet fuel made by pelletizing pulverized photographic paper waste using the above-mentioned remeltable asphalt powder as a binder. Comparative fuel Kerosene. The solution treatment was carried out by placing 18 stainless steel castings with a diameter of 300 mm and a height of 150 mm, and a total weight of 240 kg, in a heating furnace. Atmosphere inside the heating furnace (measured at the ceiling inside the furnace)
The solution treatment was carried out for 1 hour by setting the lower limit to 1050°C and the upper limit to 1100°C. Three tests were performed for each run.

[Table] Occurrence of scale
Yes No No No
As shown in the results in Table 1 above, compared to the net calorific value of kerosene used in a kerosene combustion burner device,
Although the granular solid fuel used in the burner device of the present invention is a low-calorie fuel with approximately 38 to 63% of the calorie content of kerosene, by using the device of the present invention, the combustion efficiency is significantly improved, and the kerosene It can be seen that the solution treatment can be performed with the required amount of heat per 1 kg of processed material which is gradually reduced compared to the case where a combustion burner device is used, and furthermore, it is possible to significantly reduce the cost ratio. Furthermore, in Examples 1, 2, and 3, no scale was observed and the finish was judged to be comparable to the surface of the product processed by an electric furnace, whereas in Comparative Example 1, the surface An oxide film was formed locally, resulting in a pale black skin, and the product yield decreased. Furthermore, in the case of Examples 1, 2 and 3, 1.5
A detailed inspection of the inner wall of the combustion chamber after the first operation revealed no burnout, adhesion or accumulation of clinker, slag, etc.

[Brief explanation of drawings]

FIG. 1 of the accompanying drawings is a sectional view of a typical example of the burner device of the present invention, and FIG.
FIG. 3 is a cross-sectional view of the primary combustion zone in a direction perpendicular to the cross-sectional view of the figure, and FIG. 3 is a cross-sectional view showing an example of the connection between the fuel storage tank and the primary combustion zone of the burner device of the present invention.

Claims (1)

[Scope of Claims] 1. A first having a fuel supply port for supplying granular solid fuel accompanied by primary combustion air and an ignition means for igniting the fuel at one end and a primary combustion outlet at the other end. a secondary combustion zone, a plurality of secondary air supply nozzles provided on a side wall of the primary combustion zone and arranged to form a swirling flow of secondary combustion air traveling in the direction of the primary combustion outlet; a secondary combustion zone having an inlet connected to the outlet of the primary combustion zone at one end and a secondary combustion outlet at the other end; a plurality of tertiary air supply nozzles arranged to form a swirling flow of tertiary combustion air traveling toward the secondary combustion outlet; 1. A burner device for powdery solid fuel, characterized in that a flame length adjusting air supply port directed toward the secondary combustion zone is provided at a connecting portion with the secondary combustion zone. 2. The primary combustion zone and the secondary combustion zone are
The burner device for powdery solid fuel according to claim 1, wherein the burner device is connected so that the central axes of the swirling flow in the direction of movement are positioned substantially coaxially.