JP2007139391A - Solid fuel combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate the maintenance of a solid fuel combustion device with a simple structure. <P>SOLUTION: This solid fuel combustion device 1 comprises a combustion furnace 3 which burns solid fuel supplied onto a stationary grate 2, and a combustion air supplying chamber 4 which is formed in a lower layer of the combustion furnace 3 and supplies combustion air 10 to the combustion furnace 3. The stationary grate 2 has an opening for stirring the combustion air 10, which is supplied to the combustion furnace 3 from the combustion air supplying chamber 4, in the circumferential direction of the combustion furnace 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solid fuel combustion apparatus for burning solid fuel such as biomass and waste, and more particularly to a solid fuel combustion apparatus that facilitates maintenance with a simple structure.

  Conventionally, there is a grate combustion type combustion apparatus that burns solid fuel on a grate. This grate combustion system is very widely applied from a small combustion device to a large garbage incineration plant. In addition, the combustion apparatus of the above-described grate combustion system has a combustion reaction that progresses between the solid fuel supplied on the grate and the combustion air supplied from below the grate, and the combustion ash falls by its own weight from the gap of the grate. What you do is common. Such grate is classified into a fixed type and a movable type.

  The fixed grate has a simple structure and is further subdivided into a horizontal type, a step type, a tilt type, and the like. In common with these fixed grate, a clinker in which combustion ash is glassy may stick to the grate and block the opening of the grate. Therefore, there are problems such as obstructing stable combustion that is indispensable for maintaining automatic operation, and problems such as troublesome maintenance such as cleaning. Therefore, it is common to adopt a batch-type operation mode in which after the combustion is completely completed, cleaning is performed and then a new solid fuel is introduced.

  Also, in order to prevent the clinker from blocking the opening of the grate, a pusher and rake that appropriately level the solid fuel and fuel ash on the fixed grate, a mechanical device that scrapes off the combustion ash from the bottom of the hearth at a constant speed, etc. Some of them have

  Furthermore, in order to prevent the clinker from blocking the opening of the grate, the first fixed grate and an air passage located below the first fixed grate and smaller than the first fixed grate A combustion apparatus is disclosed that includes a second fixed grate having a hole and a pusher that pushes fuel ash on the second fixed grate to an ash outlet. (For example, refer to Patent Document 1.)

On the other hand, the movable grate is characterized in that the grate is moved continuously or periodically to prevent agitation of the solid fuel and blockage of the grate due to combustion ash. This movable grate is further subdivided into a rocking type, a sliding type, a reversing type, a moving type, a rotating type and the like. These movable grate need to synchronize solid fuel injection, drying, gasification combustion, flame combustion, flaming combustion, ash discharge reaction / processing speed, grate movable speed, and the like.
JP-A-1-263411

  By the way, in the technique of the above-mentioned patent document 1, in order to prevent the clinker from blocking the opening of the grate, the combustion ash is dropped from the first fixed grate to the second fixed grate, and the combustion ash is pushed by the pusher. However, there is a problem that the structure becomes complicated because the fixed grate must have a two-stage structure and the pusher must be controlled.

  In addition, the movable grate combustion system prevents the clogging of the grate and facilitates maintenance. However, solid fuel injection, drying, gasification combustion, flame combustion, vertical combustion, ash emission reaction・ Complicated control must be performed in order to synchronize the processing speed, grate movable speed, etc., so it is difficult to perform synchronous control according to the type of fuel, and problems such as complicated structure, large equipment, and high cost There was no general purpose.

  The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide a solid fuel combustion apparatus that facilitates maintenance with a simple structure.

  In order to solve the above problems, a solid fuel combustion apparatus according to the present invention includes a combustion furnace that burns solid fuel supplied on a fixed grate, and a combustion air that is formed in a lower layer of the combustion furnace and supplies combustion air to the combustion furnace. In the solid fuel combustion apparatus including the combustion air supply chamber, the fixed grate has an opening for turning the combustion air supplied from the combustion air supply chamber to the combustion furnace in the circumferential direction of the combustion furnace. The configuration.

  According to this configuration, the combustion air supplied from the combustion air supply chamber swirls in the circumferential direction of the combustion furnace without requiring control, and the combustion ash generated by the combustion of the solid fuel by swirling of the combustion air also swirls However, it comes into contact with the furnace wall and the top of the furnace and becomes finer, and is easily discharged together with the combustion gas.

  Preferably, the fixed grate is a combination of a plurality of block members each having a substantially fan-shaped upper surface, and a gap portion formed radially with respect to the center of the combustion furnace between the plurality of block members is the combustion air. It becomes the structure used as the said opening part made to turn in the circumferential direction of the said combustion furnace.

More preferably, the fixed grate is detachable from the combustion furnace.
In addition, a cylindrical member standing in the combustion furnace, a combustion ash separation portion formed in a lower layer of the combustion air supply chamber, and communicating with the cylindrical member and passing through the combustion air supply chamber It is good to set it as the structure further provided with the combustion gas passage part which opens to the said combustion ash separation part, and leads the combustion gas and combustion ash which arise in the said combustion furnace to the said combustion ash separation part.

In that case, the said cylindrical member is good to set it as the structure which can be attached or detached with respect to the said combustion furnace.
Further, the combustion air supply chamber uses a combustion air supply fan that takes in air outside the solid fuel combustion device, and sucks a part of the combustion gas from the combustion ash separation unit and mixes it with the combustion air. A configuration having an ejector is preferable.

  Preferably, the combustion furnace is disposed below a solid fuel supply port for supplying the solid fuel to a furnace wall formed on a side surface of the combustion furnace, and burns the solid fuel. It is good to have composition which has a combustion means to do.

  The combustion furnace includes a solid fuel supply port for supplying the solid fuel to a top of the combustion furnace, and the solid fuel supplied from the solid fuel supply port located below the solid fuel supply port. It is good to set it as the structure which has a dispersion member to disperse | distribute a fuel on the said fixed grate.

  According to the present invention, the fixed grate has the opening for turning the combustion air supplied from the combustion air supply chamber to the combustion furnace in the circumferential direction of the combustion furnace, so that the combustion supplied from the combustion air supply chamber The air swirls in the circumferential direction of the combustion furnace without the need for control, and the combustion ash generated with the combustion of the solid fuel is swirled by the swirling of the combustion air, and becomes finer by contacting the furnace wall and the top of the furnace, Since it becomes easy to discharge together with the combustion gas, maintenance can be facilitated with a simple structure.

Hereinafter, a solid fuel combustion apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing a solid fuel combustion apparatus according to an embodiment of the present invention. FIG. 2A is an exploded view showing a fixed grate of the combustion apparatus, and FIG. 2B is a schematic sectional view showing an opening of the fixed grate. FIG. 3 is a sectional view of the fixed grate and the combustion part of the solid fuel combustion apparatus as seen from the furnace top side.

  In FIG. 1, a solid fuel combustion apparatus 1 includes a fixed grate 2, a combustion furnace 3, a combustion air supply chamber 4, a combustion ash separator 5, an ejector 6, a cylindrical member 7, a combustion gas passage 8 and the like. As shown in FIG. 2A, the fixed grate 2 is formed by combining a plurality of block members 9, and each block member 9 is arranged on the innermost peripheral portion of the fixed grate 2 among the top plate 9 a and the lower portion of the top plate 9 a. The inner leg portion 9d is formed at a corresponding position, and the outer leg portion 9e is formed at a position corresponding to the outermost peripheral portion.

  Here, the top surface of the top plate 9a has a substantially fan-like shape, and has a curved surface or a flat inclined surface 9c inclined downward with respect to a horizontal plane from the dotted line portion shown in FIG. At the tip of the inclined surface 9c, a protrusion 9b is formed below the top plate 9a of the adjacent block member 9 and extends with a predetermined gap. 2B, an opening B is formed between the inclined surface 9c and the adjacent top plate 9a, and the combustion air 10 is swirled in the circumferential direction of the combustion furnace (arrow a shown in FIG. 2A). ing. Moreover, this opening part B is opening radially with respect to the combustion furnace central axis A shown to FIG. 2A.

  1 is supplied to the furnace wall 3a of the combustion furnace 3 shown in FIG. 1 where a combustion means (not shown) such as an ignition oil burner is disposed, and the solid fuel is positioned above the combustion part 3b. For this purpose, a solid fuel supply port 3c is formed. The solid fuel supply port 3c is located above the combustion unit 3b as a position where the solid fuel is dispersed by blowing air from an ignition oil burner or the like as combustion means disposed in the combustion unit 3b.

  Further, as shown in FIG. 3, the combustion part 3 b has an opening between the block members 9 in substantially the same direction as the direction a in which the combustion air is swirled, and in the tangential direction b with respect to the outer peripheral part of the block member 9. A combustion means (not shown) is positioned so as to burn the solid fuel. As shown in the figure, each block member 9 is arranged with a predetermined interval between the furnace wall 3a and a cylindrical member 7 described later in order to facilitate attachment and detachment. In addition, it is desirable that the furnace wall 3a and the furnace top 3d of the combustion furnace 3 are provided with a furnace cleaning port, a flame detector, a furnace pressure detection port, a furnace viewing window, and the like.

  Next, the combustion air supply chamber 4 is formed in the lower layer of the combustion furnace 3, and supplies the combustion air 10 to the combustion furnace 3 through the openings between the block members 9 of the fixed grate 2. An ejector 6 is disposed on the side wall 4 a of the combustion air supply chamber 4. This ejector 6 uses a combustion air supply fan (not shown) that takes in air outside the solid fuel combustion apparatus 1, and from the combustion ash separation unit 5 formed in the lower layer of the combustion air supply chamber 4 to a combustion ash separation unit. A part of the combustion gas 11 is sucked through the gap 4 c between the partition plate 4 b and 5 and mixed with the combustion air 10.

  Here, the ejector 6 is tapered toward the opening 6 b on the combustion air supply chamber 4 side, and is fixed to a part of the outer periphery of the opening 6 b and is a cylindrical member 6 a coaxial with the ejector 6. Is provided. In addition, it is desirable that the side wall 4a of the combustion air supply chamber 4 is provided with a combustion ash outlet for taking out the combustion ash falling from the opening of the fixed grate 2.

  Further, the cylindrical member 7 standing in the combustion furnace 3 is positioned on a circular plate-shaped member 8a having an open center so that the uppermost part of a cylindrical combustion gas passage 8 described later is fitted. Yes. In the plate-like member 8a, the inner leg portion 9d of the block member 9 is also positioned with a predetermined distance from the tubular member 7. Further, the outer leg portion 9e of the block member 9 is located at a predetermined distance from the furnace wall 3a on a support portion 4d formed so as to protrude from the side wall 4a of the combustion air supply chamber 4.

  Here, as described above, the inner leg portion 9d and the outer leg portion 9e of the block member 9 are positioned at predetermined intervals on the cylindrical member 7 and the side wall 4a, respectively. Easy to put on and take off. In order to make the cylindrical member 7 and the block member 9 detachable and to remove the clinker in the combustion furnace 3, it is assumed that the furnace wall 3a is provided with a furnace cleaning port.

  Further, for example, the cylindrical combustion gas passage portion 8 communicates with the cylindrical member 7 in order to guide the combustion gas 11 and combustion ash generated in the combustion furnace 3 to the combustion ash separation portion 5, and the combustion air supply chamber 4. And the partition plate 4b is penetrated and the combustion ash separation part 5 is opened. The combustion gas 11 and the combustion ash guided to the combustion ash separation unit 5 will be described later, but the combustion ash having a relatively large particle size is separated in the combustion ash separation unit 5 and sent to a heat exchanger (not shown) or the like. .

Next, combustion of solid fuel using the above-described solid fuel combustion apparatus 1 will be described with reference to FIG.
First, solid fuel such as pellets is supplied onto the fixed grate 2 from the solid fuel supply port 3 c. At this time, the solid fuel is dispersed on the fixed grate 2 by blowing air from an ignition oil burner or the like as a combustion means located below the solid fuel supply port 3c and disposed in the combustion section 3b. Then, the solid fuel is burned by an ignition oil burner or the like.

  Here, when the solid fuel is burned, the opening shown in FIG. 2B is opened between the plurality of block members 9 forming the fixed grate 2 so that the combustion air 10 is swirled in the circumferential direction of the combustion furnace 3. Combustion air 10 is supplied from the combustion air supply chamber 4 via B. Therefore, the combustion air 10 turns in the circumferential direction of the combustion furnace 3.

The combustion air 10 supplied from a combustion air supply fan (not shown) to the combustion air supply chamber 4 is dispersed in the combustion air supply chamber 4 by a cylindrical member 6 a provided in the ejector 6.
As the combustion air 10 turns, the combustion gas 11 and combustion ash generated by the combustion of the solid fuel also rise while turning. At that time, the combustion ash comes into contact with the furnace wall 3a, the top 3d, etc., and becomes finer.

  Next, the combustion gas 11 and the combustion ash are sucked from the cylindrical member 7 and guided to the combustion ash separation unit 5 through the combustion gas passage unit 8. The combustion ash reaches the combustion ash separation unit 5 having a large flow path from the combustion gas passage 8 and the flow velocity is lowered and the flow direction is changed, so that the combustion ash having a relatively large particle size is separated. In this way, the combustion ash becomes fine in the combustion furnace 3 and the like, and after being partially separated by the combustion ash separator 5, the combustion ash is blown to the heat exchanger (not shown) together with the combustion gas 11.

Here, a part of the combustion gas 11 that has reached the combustion ash separator 5 is sucked into the combustion air supply chamber 4 through the gap 4 c of the partition plate 4 b and is supplied to the combustion furnace 3 together with the combustion air 10 again. As described above, the combustion of the solid fuel is completed.
FIG. 4 is a schematic sectional view showing an example in which the solid fuel combustion apparatus is applied to a hot water generator.

  The solid fuel combustion device 1 is installed in a suspended state in an outer wall 12, and the space between the solid fuel combustion device 1 and the outer wall 12 is filled with water 13 as a heat medium. The water 13 flows by a built-in or external circulation pump, and is controlled to a target temperature by a temperature controller (not shown). Moreover, the water 13 is supplied from the supply port 12a formed above the furnace top 3d here.

  In the figure, the combustion gas 11 that has passed through the combustion ash separation unit 5 rises again while taking heat away from the water 13, and the combustion ash and the combustion gas 11 having a small particle size that are not separated by the ash separation unit 5 are not shown. It is discharged from the outlet.

FIG. 5 is a schematic sectional view showing an example in which the solid fuel combustion apparatus is applied to a hot air generator.
The solid fuel combustion apparatus 1 is installed in a suspended state in the outer wall 14, and air as a heat medium is filled between the solid fuel combustion apparatus 1 and the outer wall 14. The air flows by the blower fan 15 disposed above the furnace top 3d, and is controlled to a target temperature by a temperature controller (not shown).

  In the figure, the combustion gas 11 that has passed through the combustion ash separation unit 5 rises again while being deprived of heat by the air as the heat medium, and the combustion ash and combustion gas 11 having a small particle size that has not been separated by the ash separation unit 5. Is discharged from an outlet (not shown).

  As described above, according to the solid fuel combustion apparatus 1 according to the present embodiment, the fixed grate 2 converts the combustion air 10 supplied from the combustion air supply chamber 4 to the combustion furnace 3 into the circumferential direction a of the combustion furnace 3. The combustion air 10 supplied from the combustion air supply chamber 4 swirls in the circumferential direction a of the combustion furnace 3 without requiring control, and the combustion air 10 swirls the solid fuel. The combustion ash generated by the combustion of the gas also swirls, comes into contact with the furnace wall 3a, the furnace top 3d, etc., and becomes easy to be discharged together with the combustion gas 11. Therefore, maintenance can be facilitated with a simple structure.

  Further, the fixed grate 2 is formed by combining a plurality of block members 9 whose upper surfaces are substantially fan-shaped, and an opening B formed radially with respect to the center A of the combustion furnace 3 between the plurality of block members is defined as combustion air. Since the block member 9 can be easily attached and detached by setting the opening 10 to be rotated in the circumferential direction a of the combustion furnace 3, the fixed grate 2 can be attached to and detached from the combustion furnace 3.

  Further, by dispersing the solid fuel supplied from the solid fuel supply port 3c on the fixed grate 2 by an ignition oil burner or the like as a combustion means located below the solid fuel supply port 3c of the combustion furnace 3 Solid fuel can be burned efficiently, and maintenance can be facilitated.

  Further, the combustion furnace 3 has combustion means for burning solid fuel in a direction substantially the same as the direction a in which the opening B swirls the combustion air 10 and in a tangential direction b with respect to the outer peripheral portion of the fixed grate 2. Thus, since the solid fuel is burned by the combustion air 10 supplied so as to swirl in the circumferential direction a of the combustion furnace 3 from the opening B, the solid fuel can be burned efficiently and maintenance can be further facilitated.

  In addition, the cylindrical member 7 standing in the combustion furnace 3, the combustion ash separator 5 formed in a lower layer of the combustion air supply chamber 4, and the cylindrical member 7 are communicated with and penetrate the combustion air supply chamber 4. Then, the combustion gas 11 and the combustion ash are opened by providing the combustion ash separation unit 5 and the combustion gas 11 generated in the combustion furnace 3 and the combustion gas passage unit 8 for introducing the combustion ash to the combustion ash separation unit 5. The combustion ash is separated from the combustion furnace 3 to the combustion ash separation unit 5, and the flow direction of the combustion gas 11 and the combustion ash is changed in the combustion ash separation unit 5 so that the combustion ash is easily separated from the combustion gas 11 and the combustion gas passes through. Since the portion 8 penetrates through the combustion air supply chamber 4, the solid fuel combustion device 1 can be downsized.

  Further, since the cylindrical member 7 is detachably attached to the combustion furnace 3, the clinker or the like fixed to the cylindrical member 7 can be easily cleaned, and maintenance is further facilitated.

  Further, by using a combustion air supply fan (not shown) that takes air outside the solid fuel combustion apparatus 1 into the combustion air supply chamber 4, a part of the combustion gas 11 is sucked from the combustion ash separation unit 5, and the combustion air 10 Since the ejector 6 to be mixed in was disposed, the formation of clinker was suppressed by the recirculation of the combustion gas 11, and the combustion with less excess air was realized with a small excess air ratio. Further, since the recirculation amount of the combustion gas 11 is a part of the combustion gas 11 sucked from the gap 4c of the partition plate 4b between the combustion device 4 and the combustion ash separator 5, a high static pressure fan or compressor The power consumption can be reduced.

FIG. 6 is a schematic sectional view showing a solid fuel combustion apparatus according to another embodiment of the present invention.
The solid fuel combustion apparatus 21 according to the present embodiment differs from the first embodiment only in that the position of the solid fuel supply port 3e of the combustion furnace 3 is formed not on the furnace wall 3a but on the furnace top 3d. Description is omitted.

  In the figure, the combustion furnace 3 has a solid fuel supply port 3c for supplying solid fuel to the top 3d of the combustion furnace. Further, below the solid fuel supply port 3c, an umbrella 3f as a dispersion member for dispersing the solid fuel supplied from the solid fuel supply port 3c on the fixed grate 2 is solidified by, for example, two connecting portions 3g and 3g. It is connected to the bottom surface of the fuel supply port 3c.

  According to the solid fuel combustion device 21 according to the present embodiment, in addition to the effects of the solid fuel combustion device 1 according to the above-described embodiment, the solid fuel supplied from the solid fuel supply port 3c is placed on the fixed grate 2 by the umbrella 3f. By dispersing in the solid fuel, the solid fuel can be efficiently burned and maintenance can be facilitated.

  Note that the solid combustion device 21 according to the present embodiment can also be applied to the hot water generator shown in FIG. 4 and the hot air generator shown in FIG. In that case, the water supply port 12c shown in FIG. 4 and the blower fan 15 shown in FIG. 5 may be arranged so as to avoid the solid fuel supply port 3c.

It is a schematic sectional drawing which shows the solid fuel combustion apparatus which concerns on one Embodiment of this invention. It is an exploded assembly figure which shows the fixed grate of the said solid fuel combustion apparatus. It is a schematic sectional drawing which shows the opening part of the said fixed grate. It is sectional drawing which looked at the fixed grate and combustion part of the said solid fuel combustion apparatus from the furnace top side. It is a schematic sectional drawing which shows the example which applied the said solid fuel combustion apparatus to the warm water generator. It is a schematic sectional drawing which shows the example which applied the said solid fuel combustion apparatus to the warm air generator. It is a schematic sectional drawing which shows the solid fuel combustion apparatus which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid fuel combustion apparatus 2 Fixed grate 3 Combustion furnace 3a Furnace wall 3b Combustion part 3c Solid fuel supply port 3d Furnace top 3e Solid fuel supply port 3f Umbrella 3g Connection part 4 Combustion air supply chamber 4a Side wall 4b Partition plate 4c Crevice 5 Combustion Ash separation part 6 Ejector 6a Cylindrical member 6b Opening part 7 Tubular member 8 Combustion gas passage part 8a Plate member 9 Block member 9a Top plate 9b Protruding part 9c Inclined surface 9d Inner leg part 9e Outer leg part 10 Combustion air 11 Combustion Gas 12 Outer wall 12a Supply port 13 Water 14 Outer wall 15 Blower fan 21 Solid fuel combustion device A Combustion furnace central axis B Opening

Claims (8)

In a solid fuel combustion apparatus comprising a combustion furnace that burns solid fuel supplied on a fixed grate, and a combustion air supply chamber that is formed in a lower layer of the combustion furnace and supplies combustion air to the combustion furnace,
The solid grate having an opening for turning the combustion air supplied from the combustion air supply chamber to the combustion furnace in a circumferential direction of the combustion furnace.   The fixed grate is formed by combining a plurality of block members whose upper surfaces are substantially fan-shaped, and a gap portion formed radially between the plurality of block members with respect to the center of the combustion furnace burns the combustion air. The solid fuel combustion apparatus according to claim 1, wherein the opening is made to rotate in a circumferential direction of the furnace.   The solid fuel combustion apparatus according to claim 1, wherein the fixed grate is detachable from the combustion furnace. A cylindrical member standing in the combustion furnace;
A combustion ash separator formed in a lower layer of the combustion air supply chamber;
A combustion gas passage portion that communicates with the cylindrical member, passes through the combustion air supply chamber, opens to the combustion ash separation portion, and introduces combustion gas and combustion ash generated in the combustion furnace to the combustion ash separation portion The solid fuel combustion apparatus according to any one of claims 1 to 3, further comprising:   The solid fuel combustion apparatus according to claim 4, wherein the cylindrical member is detachable from the combustion furnace.   The combustion air supply chamber includes an ejector that sucks a part of the combustion gas from the combustion ash separator and mixes it with the combustion air using a combustion air supply fan that takes in air outside the solid fuel combustion device. 6. The solid fuel combustion apparatus according to claim 4, wherein the solid fuel combustion apparatus is provided.   The combustion furnace includes a solid fuel supply port for supplying the solid fuel to a furnace wall formed on a side surface of the combustion furnace, and a combustion unit that is located below the solid fuel supply port and burns the solid fuel. The solid fuel combustion apparatus according to any one of claims 1 to 6, wherein   The combustion furnace includes: a solid fuel supply port for supplying the solid fuel at a top of the combustion furnace; and the solid fuel supplied from the solid fuel supply port located below the solid fuel supply port. The solid fuel combustion apparatus according to claim 1, further comprising a dispersion member that is dispersed on the fixed grate.

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