JP6150596B2 - Solid fuel combustion device and boiler device - Google Patents

Description

  The present invention relates to a solid fuel combustion apparatus for burning a combustible material that is a granular or powdered finely divided solid that can be fluidized and transferred.

Conventionally, ash discharge processing when burning solid fuel such as soot has been carried out by scraping it manually with a scoop or the like every time a certain amount of ash is deposited on the bottom.
Also, in the case of a fine solid fuel such as a granular material, it is difficult to separate a portion where the solid fuel is burned from a portion where ash is deposited. Therefore, when a certain amount of solid fuel burns continuously, the combustion is temporarily stopped and the ash remaining in the furnace is scraped off.

  On the other hand, in a solid fuel combustion apparatus for burning a combustible material that is solid, such as granular or powdery, and can be flowed and transferred, an outer cylindrical portion that forms a cylindrical combustion chamber, A substantially inverted conical hopper portion provided continuously below the outer cylindrical portion, and a substantially planar shape of a pot having an open top surface formed in a circular pot shape, the inner lower side of the outer cylindrical portion The inner cylindrical surface of the outer cylindrical portion and the entire circumference are arranged so that a required gap is formed, the bottom portion is provided as a portion to be supplied with solid fuel such as the granular material, and the inner diameter above the bottom portion is increased. There has been proposed a solid fuel combustion apparatus (see Patent Document 1) including a combustion pot provided with a supply portion of combustion air so as to substantially generate an upward swirling airflow in a diameter portion.

According to this solid fuel combustion apparatus, it is possible to deal with fine solid fuels such as particulates and to automatically discharge ash that has been burned and floated with a simple configuration. However, the ash accumulated in the combustion pot cannot be discharged.
For this, first, the present applicant has a fuel hopper for storing solid fuel, a screw conveyor provided with a cylinder for feeding the solid fuel, and a screw inserted through the cylinder, and a screw. Solid fuel combustion device comprising a screw rotational drive device for forward and reverse rotation, and an ash discharge port provided at a cylindrical portion between the fuel hopper and the outer cylindrical portion (see Patent Document 2) Has been proposed.

  However, in a solid fuel combustion apparatus equipped with such a combustion pot, the combustion efficiency tends to decrease depending on the combustion conditions such as the state of solid fuel is not always constant, and the combustion temperature rises to a sufficiently high temperature. May not. In such a case, clinker is likely to be generated, and if the clinker is accumulated in the combustion pot, it becomes difficult to continue efficient combustion. In addition, the clinker sticks in the combustion pot and is difficult to discharge with a screw conveyor, which deteriorates combustion performance and makes maintenance work difficult.

JP 2008-261527 A (first page) JP 2011-127844 A (first page)

The problem to be solved with respect to the solid fuel combustion device and the boiler device is that when solid fuel is burned in the combustion pot, clinker is generated and accumulated in the combustion pot depending on the combustion conditions, and efficient combustion is achieved. It is difficult to continue.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a solid fuel combustion apparatus and boiler apparatus that can increase combustion temperature and improve combustion efficiency so as to prevent clinker generation as much as possible and continue efficient combustion. It is to provide.

The present invention has the following configuration in order to achieve the above object.
According to one aspect of the solid fuel combustion apparatus according to the present invention, in the solid fuel combustion apparatus for combusting combustible material that is granular or powdered solid and can be flowed and transferred, An outer cylindrical portion that forms a cylindrical combustion chamber, an ash recovery hopper provided so that ash can be continuously recovered below the outer cylindrical portion, and a planar pot shape in a flat shape with an open upper surface The bottom part of the pot including the bottom part is provided as a solid fuel supply part, and is arranged on the inner lower side of the outer cylindrical part so as to generate a gap over the inner peripheral surface and the entire circumference of the outer cylindrical part. In addition, a combustion pot provided with an air supply hole portion for supplying pressurized air for combustion inwardly to the upper portion of the pot having an enlarged inner diameter, and pressurized air for combustion at the center of the combustion pot A plurality of pressurized air jets to the tip so as to supply An air discharge hole, provided with said outer cylindrical wall inserted and the tip top in and pipe air supply which is arranged at a position state in a central portion of the combustion pot from the air The tip of the supply pipe is provided in a shape whose volume is larger than the part of the pipe that reaches the tip, and pressurized air is injected radially outward from the center of the combustion pot. A plurality of air discharge holes are provided in the horizontal direction so as to blow away the ash generated by burning in the pot for the outside and send it to the ash recovery hopper through the gap, and the combustion It is arranged at the height position of the upper surface of the pot.

  According to an embodiment of the boiler apparatus of the present invention, a heat exchanger is disposed above the combustion pot in the solid fuel combustion apparatus and above the inside of the cylindrical combustion chamber. It can be characterized by having been comprised.

  According to the solid fuel combustion apparatus and the boiler apparatus of the present invention, the combustion temperature can be increased and the combustion efficiency can be improved so as to prevent the generation of clinker as much as possible and continue efficient combustion. It has a special advantageous effect.

It is sectional drawing which shows the example of the form of the boiler apparatus concerning this invention.

Hereinafter, an example of a boiler apparatus employing a solid fuel combustion apparatus according to the present invention will be described in detail with reference to the accompanying drawings (FIG. 1). The boiler solid fuel combustion device of this boiler device is a device that burns combustible materials that are granular or powdered solids that can be flowed and transported.
Note that the granular or powdered subdivided solid is, for example, a pulverized product of woody material or grassy material such as wood chips or sawdust. In addition, such finely divided solids that have been appropriately agglomerated (pelletized) so as to have fluidity, mushroom waste culture medium and organic waste such as garbage generated in fungus bed cultivation What was dried to a granular form as a raw material is also contained.

Reference numeral 10 denotes an outer cylindrical portion, which is a main body forming a cylindrical combustion chamber 15.
According to the outer cylindrical portion 10, the inner peripheral surface 11 is formed in a substantially cylindrical shape. That is, the inner peripheral surface 11 is formed so as to correspond to a smooth curved surface of the cylindrical inner surface of the cyclone dust collector, and the form of the outer surface 13 is not particularly limited. According to this, the inner peripheral surface 11 suitably functions as a guide surface for smoothly guiding and dropping the ash particles separated from the air flow by centrifugal force or the like.

Reference numeral 20 denotes an ash recovery hopper, which is provided on the lower side of the outer cylindrical portion 10 so that ash can be recovered continuously.
According to the ash recovery hopper portion 20, the inner surface 21 is formed in a reverse taper shape. That is, the inner surface 21 is formed to correspond to the hopper portion of the cyclone dust collector, and the form of the outer surface is not particularly limited. According to this, the inner surface 21 suitably functions as a guide surface for collecting and collecting ash particles smoothly.

An ash discharging device 25 is connected to the lower portion of the ash recovery hopper 20 so as to automatically discharge the ash.
The ash discharging device 25 of this embodiment is configured by a screw conveyor. According to this, the ash 22 deposited in the ash recovery hopper 20 can be automatically discharged continuously or intermittently to a required ash storage unit (ash recovery can 26). For this reason, an operator's labor can be saved and work efficiency can be improved.

Reference numeral 30 denotes a combustion pot, which is formed in a circular pot shape with an open upper surface and has a required shape over the entire inner circumference of the outer cylindrical portion 10 on the inner lower side of the outer cylindrical portion 10. It arrange | positions so that the space | gap 31 may arise.
In this embodiment, the outer cylindrical portion 10 and the combustion pot 30 are arranged so that the gaps 31 between the inner peripheral surface 11 of the outer cylindrical portion 10 and the outer peripheral surface 32 of the combustion pot 30 are equally spaced over the entire circumference. It is arranged concentrically. The outer peripheral surface 32 of the combustion pot 30 is formed to be substantially cylindrical.

In this combustion pot 30, a pot lower portion 33 including a bottom portion is provided as a solid fuel supply portion, and an air supply hole for supplying combustion air inward to the pot upper portion 34 having an enlarged inner diameter. A portion 35 is provided. According to this, air can be sent to the solid fuel 50 and burned suitably by the principle of fire-blown bamboo. A blower 36 supplies combustion air to the air supply hole 35.
In addition, the form of the combustion pot 30 is not limited to this, For example, you may form so that an inner space shape may become an inverted truncated cone shape (taper shape) gradually diameter-expanding upwards. According to this, ascending air current is easily generated along the slope. In addition, the direction of air ejection from the air supply hole 35 may be provided obliquely so as to generate a swirling flow.

According to this, the ash after combustion of the solid fuel 50 is caused to rise by the updraft caused by the combustion. Further, since an ascending airflow hardly occurs around the center of the cylindrical combustion chamber 15, the ash is suitably separated from the exhaust flow, and the ash settles along the inner peripheral surface 11 of the cylindrical combustion chamber 15. .
Since the ash is light, it easily rises by the rising air flow generated by burning the solid fuel itself and the flow of supplied combustion air, and can float without staying in the combustion pot 30. The ash separated from the combustion air flow (exhaust flow) as described above travels along the inner peripheral surface 11 of the outer cylindrical portion 10 and the inner surface 21 of the ash recovery hopper portion 20, and the lower part of the ash recovery hopper portion 20. Collected. For this reason, ash can be suitably discharged.
In this way, since the ash is scattered sequentially and comes out of the combustion pot 30, the solid fuel 50 that is sequentially supplied is rarely covered with the ash. Therefore, oxygen is suitably supplied to the solid fuel 50, and the solid fuel 50 is burned efficiently.

The solid fuel combustion apparatus according to the present invention includes a plurality of air discharge holes 81 through which pressurized air is ejected at the tip so as to supply the compressed air for combustion to the center of the combustion pot 30. An air supply pipe 80 is provided so as to be inserted from the wall of the outer cylindrical portion 10 into the inside. In the present embodiment, as shown in FIG. 1, the distal end portion of the air supply pipe 80 from which the pressurized air is ejected is arranged on the upper side of the combustion pot 30 and in the central portion. The air supply pipe 80 is connected to a blower 82 installed outside the outer cylindrical portion 10, and can be provided with an air volume adjusting means so as to supply pressurized air of a required air volume.
According to this, fresh air can be suitably sent to the solid fuel supplied to the combustion pot 30 to improve the combustion efficiency and increase the combustion temperature, thereby preventing the occurrence of clinker as much as possible. can do. By preventing the generation of clinker, efficient combustion can be continued properly.

Furthermore, in the solid fuel combustion apparatus according to this embodiment, the tip of the air supply pipe 30 is provided in a shape whose volume is larger than the portion of the pipe reaching the tip, and the pressurized air is used for combustion. A plurality of air discharge holes 81 are provided in the horizontal direction so as to be ejected radially outward from the central portion of the pot 30. The shape of the tip portion may be a cylindrical shape or a polygonal shape such as a square larger than the diameter of the pipe leading to the tip portion, and a plurality of air discharge holes 81 are appropriately provided in that portion, with good balance in all directions. The pressurized air is preferably discharged as uniformly as possible.
According to this, it will be in the state which supplies pressure air to a solid fuel a little indirectly with appropriate directionality, and can supply fresh air appropriately to a solid fuel. Further, since the circular combustion pot 30 is radially injected outward in the radial direction, the ash generated by burning in the combustion pot 30 is appropriately blown out to the outside. 31 can be smoothly sent to the ash collecting hopper 20.

That is, according to the present invention, when heated air is blown by the air supply pipe 80 to the central portion where the combustion pot 30 in the cylindrical combustion chamber 15 constituting the combustion furnace is arranged, a solid such as a mushroom waste medium is obtained. Because the fuel comes in contact with fresh air, it can be burned throughout the furnace to maintain a high combustion temperature.
Thus, when the temperature in the combustion furnace becomes high, the temperature of the blown air from the pipe to be blown rises, the fuel is further dried and burns easily, and the temperature in the combustion furnace rises further.

When the temperature in the combustion furnace rises to 800 to 850 ° C., the solid fuel such as powder is lightened, blown away with pressurized air and not accumulated in the combustion furnace, the clinker is less solidified, and burns for a long time. Even so, a constant temperature can be maintained.
In addition, although stainless steel (SUS316) is used as a ventilation pipe, for example, since pressurized air is sent in the air supply pipe 80, it can cool appropriately and there is no fear of burning out. .

Reference numeral 51 denotes a fuel hopper, which is a storage tank in which the solid fuel 50 is stored. The fuel hopper 51 is charged with solid fuel from the outside and stored.
Reference numeral 52 denotes an agitation device that agitates so as to be sent to the lower screw conveyor 40 while preventing the solid fuel 50 from solidifying while slowly rotating. Reference numeral 53 denotes a drive device for the stirring device.

  Reference numeral 40 denotes a screw conveyor which is connected so as to extend from the side surface of the combustion pot 30 to the inner pot lower portion 33 as a means for supplying the solid fuel 50 from the fuel hopper 51 to the pot lower portion 33, and for sending the solid fuel 50. A cylindrical body 41 and a screw 42 inserted through the cylindrical body 41 are provided. In this embodiment, the screw conveyor 40 is arranged horizontally, and the solid fuel 50 is sent horizontally through the cylindrical body 41.

Reference numeral 44 denotes a screw rotation drive device that rotates the screw 42 forward and backward, supplies the solid fuel 50 to the combustion pot 30 during forward rotation, and scrapes the ash remaining in the combustion pot 30 during reverse rotation. Is provided.
As the screw rotation drive device 44, for example, a drive device constituted by an electric motor with a speed reducer and a speed reduction mechanism using a chain can be employed.

  Reference numeral 43 denotes a discharge port portion, which is provided so that it can be opened and closed in order to discharge ash to a portion of the cylindrical body 41 between the fuel hopper 51 and the outer cylindrical portion 10. In the present embodiment, the discharge port portion 43 is configured by an opening 43a provided on the lower surface side of the cylindrical body 41 and a closing plate 43b that can close the opening. Without being limited to this form, for example, if a mechanism capable of automatically opening and closing the closing plate 43b is employed, the ash discharging operation can be automated.

  Thereby, the solid fuel 50 can be automatically supplied into the pot lower portion 33 of the combustion pot 30 continuously or intermittently. The means for supplying the solid fuel 50 is not limited to such a form. For example, the solid fuel 50 may be supplied obliquely from the lower side to the pot lower portion 33 of the combustion pot 30, or may be supplied from directly below according to the installation conditions of the apparatus.

It should be noted that the tip of the screw of the screw conveyor 40 is disposed so as to protrude into the pot lower portion 33 of the combustion pot 30 as shown in FIG.
According to this, the solid fuel 50 accumulated on the inner bottom surface of the combustion pot 30 can be agitated at the tip of the screw. Thus, combustion of the solid fuel 50 can be promoted, and silicon oxide can be prevented from melting and adhering to the inner surface of the combustion pot 30.

Reference numeral 45 denotes a water-cooling portion, which is provided at the distal end side of the cylindrical body 41 from which the solid fuel 50 is discharged and located inside the outer cylindrical portion 10 to cool the distal end portion of the cylindrical body. Yes. In this embodiment, it is a double pipe wound around the outer side of the cylinder 41, and is formed in a circulation channel through which water can circulate or pass. A water supply source 46 is connected to the water cooling unit 45.
By providing the water cooling portion 45 in this way, it is possible to prevent a phenomenon in which the unburned residue is solidified and adheres to the inner peripheral surface of the cylinder 41 and the rotation of the screw 42 is inhibited. In addition, it is thought that the phenomenon that the unburned residue hardens occurs when the glassy material contained in the fuel is melted once by being exposed to a high temperature and solidified by being cooled.

In the present embodiment, a plurality of claw-like projections 42 a are provided on the tip side that extends to the pot lower portion 33 of the screw 42.
According to this, fuel and ash can be scratched so as to prevent the phenomenon that the unburned residue is solidified, and even if the unburned mass is generated, it can be crushed at an early stage. Therefore, it is possible to prevent clogging of the passage of the cylindrical body 41 through which the solid fuel 50 is fed, and a preferable continuous operation can be realized.

Reference numeral 55 denotes a heat exchanger, which can be disposed above the combustion pot 30 and above the inside of the cylindrical combustion chamber 15. The upper side of the cylindrical combustion chamber 15 is a portion where the gas generated from the solid fuel 50 burns, and is a secondary combustion portion that burns in a high-temperature flame.
A boiler apparatus can be comprised by setting it as the form which can utilize the warm air, warm water, or steam which generate | occur | produces by being heated with this heat exchanger 55. FIG.

A cyclone dust collector 61 is connected to the cylindrical combustion chamber 15 and the exhaust pipe 60 so as to collect the generated ash that cannot be discharged via the ash collection hopper 20.
According to the cyclone dust collector 61, the ash discharged from the cylindrical combustion chamber 15 along with exhaust can be suitably separated, and clean exhaust can be discharged from the chimney. Most of the ash is collected by being collected in the ash recovery hopper 20, and the remaining slight ash is separated and recovered by the cyclone dust collector 61.
Further, the ash storage part of the ash discharging device 25 and the cyclone dust collector 61 may be equipped with an ash collection can 26 that can be attached and detached with a single touch, thereby improving work efficiency.

Reference numeral 70 denotes an ignition burner, for example, a burner for burning a liquid such as kerosene or heavy oil, and the solid fuel 50 can be ignited by disposing the tip of the burner nozzle so as to face the combustion pot 30. It is good to provide as follows.
Further, when the solid fuel 50 is burned after being ignited, the supply of the liquid fuel to the ignition burner 70 may be stopped and only the air blowing function may be used. According to the air blowing function of the ignition burner 70, the combustion air can be suitably supplied to the center of the combustion pot 30 by the principle of fire-blown bamboo, and the combustion efficiency of the solid fuel 50 can be increased. Note that switching from the combustion of the ignition burner 70 to only blowing can be easily automated by controlling the supply of liquid fuel to stop.

  As described above, the present invention has been described in various ways with preferred embodiments. However, the present invention is not limited to these embodiments, and many modifications can be made without departing from the spirit of the invention. That is.

DESCRIPTION OF SYMBOLS 10 Outer cylindrical part 11 Inner peripheral surface 15 Cylindrical combustion chamber 20 Ash collection hopper part 22 Ash 25 Ash discharge device 30 Combustion pot 31 Void 33 Pot lower part 34 Pot upper part 35 Air supply hole part 40 Screw conveyor 41 Cylindrical body 42 Screw 42a Claw-like projection 43 Discharge port 44 Screw rotation drive 45 Cooling unit 50 Solid fuel 51 Fuel hopper 55 Heat exchanger 80 Air supply pipe 81 Air discharge hole 82 Blower

Claims (2)

In a solid fuel combustion apparatus for combusting combustible materials that are granular or powdered finely divided solids that can be fluidized and transported,
An outer cylindrical portion forming a cylindrical combustion chamber;
An ash recovery hopper provided so that ash can be continuously recovered below the outer cylindrical portion;
A pot including a bottom portion, which is formed in a circular pot shape with an open top surface, and is formed so that a gap is formed on the inner lower surface of the outer cylindrical portion over the inner circumferential surface and the entire circumference of the outer cylindrical portion. A combustion pot having a lower portion provided as a solid fuel supply portion and an air supply hole portion for supplying pressurized air for combustion inwardly to an upper portion of the pot having an enlarged inner diameter;
The distal end portion is provided with a plurality of air discharge holes through which pressurized air is ejected so as to supply pressurized air for combustion to the central portion of the combustion pot, and is inserted from the wall of the outer cylindrical portion, and the distal end portion Comprises an air supply pipe arranged in a state of being located at the upper side and the center of the combustion pot ,
The tip of the air supply pipe is provided in a shape whose volume is larger than the portion of the pipe reaching the tip, and pressurized air is injected radially outward from the center of the combustion pot. The plurality of air discharge holes are provided in the horizontal direction so as to blow off the ash produced by burning in the combustion pot to the outside and send the ash to the ash recovery hopper through the gap. A combustion apparatus for solid fuel, wherein the combustion apparatus is disposed at a height position on an upper surface of the combustion pot . 2. The boiler apparatus according to claim 1, wherein a heat exchanger is arranged above the combustion pot and above the inside of the cylindrical combustion chamber in the solid fuel combustion apparatus.

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