JP2009085523A - Burner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a burner capable of completely burning a fuel even if it is vegetative regenerated fuel. <P>SOLUTION: This burner 1 comprises a fuel feeder 2, a lower preheater 3 for forming a primary combustion air swirl flow, a primary combustion part 4 for performing primary combustion, a secondary combustion part 5 for performing secondary combustion, and an exhaust cylinder 6. The primary and secondary combustion parts 4, 5 comprise cylindrical first and second combustion chambers 47, 57 and cylindrical annular first and second preheating chambers 46, 56, respectively. The upper parts of the secondary combustion chambers and the second preheating chambers communicate with each other through first and second communication parts, respectively. First and second cylindrical projections 49, 59 project downward from first and second partition plates 44, 45 which partition the upper side surfaces of the second communication parts 48, 58. The primary and secondary combustion airs spirally flowing through the first and second preheating chambers 46, 56 are divided into downward swirl flows F12, F22 flowing toward the lower parts of the first and second combustion chambers 47, 57 and upward swirl flows F13, F23 flowing upward of the first and second combustion chambers 47, 57 by the first and second cylindrical projections 49, 59. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a burner used for a heat source such as a boiler, and more particularly to a burner capable of completely burning plant regenerated fuel such as wood pellets.

  Conventionally, as a burner that uses wood pellets made from recycled wood, thinned wood, etc. as fuel, a burner case connected to a rectangular combustion chamber with an air pipe for supplying combustion air, and a burner case There is a burner body that is disposed and mounted with an ignition heater, and a hopper that is provided in the burner body and has many flame holes formed on a wall surface (see, for example, Patent Document 1). An air passage is formed in the burner case to guide the combustion air supplied from the air supply pipe into the burner body. A plurality of ash processing gears for discharging ash are rotatably installed at the bottom of the burner body. A discharge cylinder for discharging the wood pellets and supplying them to the burner body is arranged above the burner body. This burner has an air heat exchanger that exchanges heat between high-temperature combustion gas and external air above the combustion chamber, and constitutes a hot air device that supplies hot air obtained by heat exchange to the outside. ing.

In the conventional burner, after preheating the inside of the burner case with an ignition heater, the wood pellets are discharged from the discharge cylinder and put into the hopper of the burner body, and the combustion air is supplied from the air supply pipe to the burner case. Is introduced into the hopper through the air passage and the flame hole. Thus, the wood pellets in the hopper are burned to generate combustion gas, and the combustion gas is sent to the air heat exchanger above the combustion chamber to exchange heat with external air.
JP 2004-191016 A

  However, in the conventional burner, combustion air is only supplied to the burner case via the air supply pipe, and combustion air is not supplied to other parts of the combustion chamber. Therefore, the wood pellets are burned only with the combustion air supplied to the burner case, and there is a problem that the combustion air tends to be insufficient, causing incomplete combustion, and the problem that a carbon component of the fuel remains and a large amount of ash is generated. is there. In addition, due to incomplete combustion, the amount of soot adhering to the combustion chamber and the heat exchanger increases, and there is a problem that it takes time to maintain the burner and the air heat exchanger. In addition, since the amount of soot contained in the combustion gas is large, a large dust collector is required, and there is a problem in that the thermal equipment using the burner is increased in size and cost. Furthermore, the plant-based renewable fuel contains polymer components such as lignin, and soot and combustion gas are likely to be generated, but these measures are not taken into consideration.

  Therefore, an object of the present invention is to provide a burner that can effectively completely burn a fuel that is relatively difficult to burn completely, such as a vegetable regenerated fuel. Another object of the present invention is to provide a burner that can effectively prevent the generation of soot, and therefore can facilitate maintenance and reduce the size of a thermal apparatus used as a heat source. Moreover, it is providing the burner which can suppress generation | occurrence | production of soot and combustion gas even if it uses plant regeneration fuel.

In order to solve the above problems, the burner of the present invention
A cylindrical combustion chamber; a cylindrical annular preheating chamber that is formed so as to surround the combustion chamber and that preheats combustion air; and a communication portion that connects the upper portion of the combustion chamber and the upper portion of the preheating chamber. With multiple stages of combustion,
The preheating chamber of the combustion part is formed so that the combustion air supplied from the lower part flows in a swirling manner toward the upper part,
The communication part of the combustion part has a flow dividing part that divides the swirling flow of the combustion air preheated in the preheating chamber into a downward swirling flow toward the lower portion of the combustion chamber and an upward swirling flow toward the upper side of the combustion chamber. Have
Combustion chambers in the second and subsequent stages of combustion include an upward swirling flow of combustion air diverted by a diversion part of the preceding combustion part and a downward swirling flow of combustion air diverted by the diversion part of the combustion part of the same stage Is configured to burn the fuel.

  According to the above configuration, the combustion section having the combustion chamber is provided in a plurality of stages, and the upward swirling flow of the combustion air from the previous stage and the downward swirling flow of the combustion air from the same stage are supplied to the second and subsequent combustion chambers. Therefore, fuel can be burned to a high degree by supplying sufficient combustion air to each stage. Moreover, in the preheating chamber of each stage, the swirling flow is made to flow around the combustion chamber to preheat the combustion air, so that the residence time of the combustion air in the preheating chamber can be sufficiently secured and sufficient preheating can be performed. Further, by flowing a swirling flow through the preheating chamber and the combustion chamber, the staying portion of the combustion air and the combustion gas can be reduced and the preheating air and the combustion gas can be efficiently flowed. Therefore, the combustion efficiency of the burner can be effectively improved, the temperature of the combustion chamber can be effectively increased, and the fuel can be completely burned. As a result, even when a plant regenerated fuel is used, for example, polymer components such as lignin can be highly oxidized and completely burned. In addition, the present invention can be applied to both solid and liquid fuels by appropriately setting the number of installation stages of the combustion chamber and the combustion section.

  Further, by forming a swirl flow in the preheating chamber and the combustion chamber, the combustion air flowing in the preheating chamber and the combustion gas flowing in the combustion chamber can be densified, so that the burner can be downsized. Further, by completely burning the fuel, the generation of ash and soot can be effectively reduced, so that the labor of maintenance of the burner can be reduced and the apparatus configuration necessary for collecting dust can be reduced. As a result, a compact and easy-to-maintain thermal apparatus can be configured by using this burner.

  In addition, since the preheating chamber is disposed on the outer peripheral side of the combustion chamber, the combustion chamber can be insulated by the combustion air passing through the preheating chamber.

  In the present invention, the vertical direction refers to the direction in which the axial lines of the cylindrical combustion chamber and the cylindrical annular preheating chamber extend. When one of the axial directions is the upper side, the other of the axial directions is the lower side. That is, the vertical direction is not related to the direction in which gravity acts, and the cylindrical combustion chamber and the cylindrical annular preheating chamber may be arranged with the axis inclined with respect to the vertical direction. May be arranged in a substantially horizontal direction.

  In the burner of one embodiment, the combustion chamber of each stage of the combustion section is formed with a smaller diameter than the combustion chamber of the preceding stage combustion section.

  According to the above embodiment, by reducing the diameter of the combustion chamber in the downstream combustion section, the flow rate and pressure of the combustion gas increase as the fuel gas flows into the downstream combustion section and the combustion process proceeds. As a result, the combustion temperature can be increased toward the later stage to increase combustion efficiency and promote complete combustion. Here, the fuel gas includes fine particles of fuel and gasified fuel obtained by thermal decomposition of the fuel.

  The burner of one embodiment is provided with a fuel supply device that continuously supplies fuel to the combustion chamber of the lowermost combustion section.

  According to the said embodiment, by supplying fuel continuously, a fuel can be burned stably and a combustion gas can be produced | generated. In particular, when a plant regenerated fuel that is relatively difficult to ignite is used, the combustion efficiency can be greatly improved as compared to batch-type fuel supply.

  In addition, as a burner of another embodiment, a cylindrical lower preheating chamber for preheating combustion air is disposed below the combustion chamber of the lowermost combustion unit, and the fuel supply port of the fuel supplier is provided. It is preferable to arrange an air outlet around which the combustion air preheated in the lower preheating chamber is blown out. According to this embodiment, the swirl flow can be generated by effectively preheating the combustion air by the cylindrical lower preheating chamber disposed on the lower side of the lowermost combustion chamber. In addition, by blowing the preheated combustion air in a swirling manner from the air outlet around the fuel supply port, the combustion air can be efficiently supplied to the fuel discharged from the fuel supply port. Further, a swirl flow of combustion gas can be efficiently generated in the lowermost combustion chamber.

  The burner of one embodiment is provided with a blower for supplying combustion air to the preheating chamber of the combustion section of each stage.

  According to the above embodiment, by supplying combustion air to the preheating chamber of the combustion section of each stage, a sufficient amount of fresh combustion air can be preheated and supplied to the combustion chamber of each stage, and the combustion efficiency is improved. it can. A plurality of blowers may be provided corresponding to the preheating chambers in each stage. In this case, by controlling the blowout amount of the plurality of blowers based on the temperature and pressure of the combustion chambers of each stage, the combustion process can be finely controlled, and the combustion efficiency can be improved and complete combustion can be performed. .

  In the burner according to an embodiment, the flow dividing portion includes a cylindrical protrusion that protrudes downward from an upper wall surface that defines the communication portion.

  According to the embodiment, the swirling flow of the combustion air from each preheating chamber is caused to flow downward toward the lower portion of each combustion chamber by the cylindrical protrusion protruding downward from the upper wall surface that defines the communication portion. Thus, it is possible to effectively divert into the upward swirling flow that flows upward of each combustion chamber.

  In the burner of one embodiment, the cylindrical protrusion has a plurality of through holes.

  According to the above embodiment, by forming a plurality of through holes in the cylindrical projection, the swirling flow of the combustion air from the preheating chamber can be divided into a descending swirling flow and an rising swirling flow at an appropriate ratio. it can. Here, the through-hole may be a vertical slit parallel to the axial direction of the cylindrical protrusion, or may be an inclined slit inclined with respect to the axial direction of the cylindrical protrusion, or the axial direction of the cylindrical protrusion. It may be a transverse slit perpendicular to the surface, or may be a round hole or an elliptical hole formed dispersed in the cylindrical projection.

  In the burner according to an embodiment, the cylindrical protrusion is formed integrally with a lower end side of a cylindrical member that divides the subsequent combustion chamber and the preheating chamber.

  According to the above embodiment, the cylindrical protrusion and the cylindrical member are integrally formed, and the cylindrical protrusion is fitted to the upper wall surface that divides the communicating portion, so that the combustion chamber is formed inside and the high temperature. A cylindrical member that is easily deteriorated can be attached and detached. As a result, it is possible to easily replace the deteriorated tubular member and facilitate maintenance.

  In the burner of one embodiment, a heat radiating member is provided on the outer peripheral surface of a cylindrical member that partitions the preheating chamber and the combustion chamber.

  According to the said embodiment, the heat of a combustion chamber is efficiently thermally radiated by the combustion air which flows through the preheating chamber of an outer peripheral side via the heat radiating member provided in the outer peripheral surface of the cylindrical member. Therefore, it is possible to effectively preheat the combustion air and effectively improve the combustion efficiency of the combustion chamber. Here, the heat radiating member is preferably a spiral plate or wire wound around the outer peripheral surface of the cylindrical member. By installing a spiral plate as the heat radiating member, it is possible to improve the heat radiating efficiency and rectify the combustion air.

  The burner of one embodiment is provided with a water supply device that supplies mist-like water to the combustion chamber of the lowermost combustion section.

  According to the embodiment, by supplying mist-like water to the combustion chamber of the lowermost combustion section, it is possible to generate at least one of oxygen and hydrogen in the combustion chamber and raise the combustion temperature in the combustion chamber. it can. The water feeder can be formed including, for example, a plunger pump.

In one embodiment, the fuel feeder includes a screw conveyor,
The screw conveyor is provided with a backflow prevention unit for preventing a backflow of fuel to be conveyed.

  According to the said embodiment, continuous supply of a fuel is attained by using a screw conveyor for a fuel supply device. Moreover, the backflow prevention part of the screw conveyor effectively prevents the backflow of fuel even if the pressure in the combustion chamber to which the fuel is supplied increases.

  In the burner according to one embodiment, the backflow prevention portion is formed including a missing portion of a screw blade.

  According to the said embodiment, when the fuel stays in the defect | deletion part of the screw blade of a screw conveyor, the density of a fuel increases and a plug is formed. Even if the pressure in the combustion chamber increases, the fuel plug prevents the fuel from flowing backward. Thus, the backflow of the fuel can be prevented by a simple configuration in which the screw blade missing portion is provided. In addition, it is preferable to arrange | position the stirring member which stirs the staying fuel in the defect | deletion part of a screw blade.

  In one embodiment of the burner, the fuel supplier is configured to supply auxiliary combustion air.

  According to the embodiment, the combustion efficiency of the fuel can be increased by supplying the auxiliary combustion air together with the fuel by the fuel supplier.

  In the burner according to an embodiment, the fuel supplier includes a water supply unit that supplies water to the fuel as the combustion temperature rises abnormally.

  According to the embodiment, as the combustion temperature in the combustion chamber rises abnormally, water is supplied to the fuel by the water supply unit, and the temperature in the combustion chamber is effectively reduced. Thereby, failure of the burner due to an abnormal increase in combustion temperature can be prevented. Here, an abnormal increase in the combustion temperature can be detected, for example, by measuring the temperature of the fuel supplier. Alternatively, the temperature of the cylindrical member that defines the outer peripheral side of the preheating chamber, the temperature of the cylindrical member that defines the outer peripheral side of the combustion chamber, the temperature in the combustion chamber, and the temperature of the exhausted combustion gas are measured to detect abnormal combustion temperatures. An increase may be detected.

  In one embodiment of the burner, the fuel includes at least one of wood pellets, wood waste, plastic waste, rubber waste, RPF, and PCB waste liquid.

  According to the above-described embodiment, the burner having higher combustion efficiency than the prior art allows wood pellets, wood waste, plastic waste, rubber waste, RPF (Refuse Paper and Plastic Fuel) as fuel, and PCB (polychlorinated biphenyl) waste liquid can be burned to a high degree.

  According to the present invention, the combustion section having the combustion chamber is provided in a plurality of stages, the swirling flow is caused to flow in the preheating chamber disposed around the combustion chamber, the combustion air is preheated, Since the upward swirling flow of combustion air and the downward swirling flow of combustion air from the same stage are supplied, a sufficient amount of combustion air that has been sufficiently preheated can be supplied to the combustion chamber to highly combust the fuel. In addition, the combustion efficiency of the burner can be effectively improved and the fuel can be burnt completely. As a result, both solid and liquid fuels, such as wood pellets, wood waste, plastic waste, rubber waste, RPF and PCB waste liquid, can be burned to a high degree, and ash and soot emissions can be reduced. A highly efficient and small thermal apparatus can be configured.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view showing a burner as an embodiment of the present invention. The burner 1 burns wood pellets as fuel and is used as a heat source for a thermal device such as a boiler. The burner 1 includes a fuel supplier 2 that continuously supplies fuel, a lower preheating unit 3 that forms a swirling flow of primary combustion air, a primary combustion unit 4 that performs primary combustion of fuel, A secondary combustion section 5 that performs secondary combustion and an exhaust pipe 6 that exhausts combustion gas are roughly configured.

  The fuel supplier 2 includes a supply valve 21 for supplying wood pellets 8 from a hopper (not shown), a first screw conveyor 22 for transporting the wood pellets 8 supplied from the supply valve 21, and the first screw conveyor 22. The second screw conveyor 23 is connected to the end and supplies combustion into the combustion chamber of the primary combustion unit 4.

  The supply valve 21 is formed of a rotary valve, and controls the supply amount of the wood pellet 8 by controlling the number of rotations of the rotary blades that are rotationally driven in the casing. The first screw conveyor 22 and the second screw conveyor 23 are arranged in cylindrical casings 22a and 23a, and are arranged coaxially with the casings 22a and 23a and rotated and driven, and the rotation shafts 22b and 23b. The screw blades 22c and 23c fixed around are accommodated and formed. In the middle of the first screw conveyor 22, a screw blade defect portion is provided, and in a section corresponding to the defect portion, a plurality of stirring rods 22d extending in the radial direction spiral around the rotation shaft 22b. It is fixed. Even if the pressure in the combustion chamber in the primary combustion part 4 of the supply destination rises because the wood pellet 8 stays in the deficient part of the screw blade to form a plug of the wood pellet 8, the effect of the increased pressure is affected. It is stopped with a plug to prevent the backflow of the wood pellet 8.

  An air supply pipe 25 for supplying auxiliary combustion air is provided on the downstream side of the screw blade missing portion of the first screw conveyor 22. In addition, a water supply pipe 26 that supplies water to the fuel at an abnormally high temperature is provided on the upstream side of the screw blade defect portion of the first screw conveyor 22. That is, the flow rate control is performed by receiving an electromagnetic flow control valve 29 interposed upstream of the water supply pipe 26, a temperature sensor 27 installed in the casing 22a of the first screw conveyor 22, and an output signal S1 from the temperature sensor 27. And a control unit 28 for controlling the valve 29. When the temperature indicated by the output signal S1 of the temperature sensor 27 exceeds a predetermined reference value, the control unit 28 sets the valve opening according to the value of the output signal S1, assuming that the combustion chamber temperature of the primary combustion unit 4 has abnormally increased. The indicated signal is output to the flow control valve 29. The flow control valve 29 is configured to open and drive the valve body to supply water having a flow rate corresponding to the valve opening degree to the first screw conveyor 22 from the upstream side of the water supply pipe 26.

  The lower preheating unit 3 includes a substantially cylindrical casing 31 that forms a lower preheating chamber therein, and a primary air introduction port 32 that is provided on the outer peripheral surface of the casing 31 and introduces primary combustion air in a tangential direction. In the center of the casing 31, the second screw conveyor 23 is disposed so as to penetrate coaxially. A fuel holding portion 33 that holds fuel is formed at the upper end portion of the casing 31. The fuel holding portion 33 is inclined downward toward the center and has an annular mortar portion 33a in a plan view, and protrudes upward in connection with the inner side of the mortar portion 33a, and a sleeve-like portion 33b coaxial with the outer peripheral surface of the casing 31. And have. The distal end portion of the second screw conveyor 23 is disposed inside the sleeve-shaped portion 33 b of the fuel holding portion 33, and the fuel supply port 24 is formed at the distal end portion of the second screw conveyor 23. A cylindrical annular communication path is formed by separating the outer peripheral surface of the front end portion of the second screw conveyor 23 and the inner peripheral surface of the sleeve-shaped portion 33b of the fuel holding portion 33 by a predetermined separation distance. An air outlet 34 that blows out primary combustion air in the casing 31 is formed at the upper end of the communication path. The lower preheating unit 3 forms a swirling flow of the primary combustion air in the casing 31 by introducing air from the air introduction port 32 in the tangential direction of the cylindrical surface, and the swirling 1 Next combustion air is blown out.

  The primary combustion unit 4 includes a cylindrical first outer cylinder 41 having substantially the same diameter as the casing 31 of the lower preheating unit 3, and a cylindrical first inner cylinder disposed inside the first outer cylinder 41. 42. In the lower part of the first outer cylinder 41, a secondary air introduction port 41a for introducing secondary combustion air in the tangential direction is provided. The lower ends of the first outer cylinder 41 and the first inner cylinder 42 are connected to an annular flange 43, and the flange 43 is fixed to the upper end of the lower preheating unit 3. An annular first partition plate 44 is fixed to the upper end of the first outer cylinder 41.

  A spiral projection 45 formed by spirally winding a plate material is fixed to the outer peripheral surface of the first inner cylinder 42. A cylindrical annular first preheating chamber 46 is formed between the outer peripheral surface of the first inner cylinder 42 provided with the spiral protrusion 45 and the inner peripheral surface of the first outer cylinder 41. The secondary combustion air is introduced into the first preheating chamber 46 in the tangential direction from the secondary air introduction port 41a, so that a swirling flow of the secondary combustion air from the lower part to the upper part is formed. . A first combustion chamber 47 is formed inside the first inner cylinder 42. The fuel holding part 33 faces the lower part of the first combustion chamber 47, and a fuel supply port 24 for supplying fuel and an air outlet 34 for supplying primary combustion air are provided inside the fuel holding part 33. It is open. The first inner cylinder 42 is formed to be lower than the first outer cylinder 41, and the upper end of the first inner cylinder 42 is separated from the lower surface of the first partition plate 44 by a predetermined distance. A first communication portion 48 that connects the first preheating chamber 46 and the first combustion chamber 47 is formed between the lower surface of the first partition plate 44 and the upper end of the first inner cylinder 42. From the opening of the annular first partition plate 44, a first cylindrical protrusion 49 as a diverting portion protrudes downward from the first communication portion 48. The first cylindrical protrusion 49 is formed integrally with a second inner cylinder 52 described later, and the lower end portion of the second inner cylinder 52 is the first cylindrical protrusion 49.

  A plurality of vertical slits 49 a as through holes are formed in the first cylindrical protrusion 49. The vertical slit 49a is formed to extend substantially parallel to the axial direction of the first cylindrical protrusion 49 (and the second inner cylinder 52). By this vertical slit 49a, the swirling flow of the secondary combustion air from the first preheating chamber 46 is divided into a descending swirling flow and an ascending swirling flow at an appropriate ratio. Note that the through hole of the first cylindrical protrusion 49 is not limited to the vertical slit 49a, and an inclined slit 49b inclined with respect to the axial direction of the first cylindrical protrusion 49 as shown in the schematic development view of FIG. 2A. Good. Alternatively, as shown in the schematic development view of FIG. 2B, a transverse slit 49c orthogonal to the axial direction of the first cylindrical protrusion 49 may be used, and as shown in the schematic development view of FIG. 2C, the first cylinder The circular holes 49d formed in a distributed manner on the protrusions 49 may be used. However, it is not always necessary to provide the first cylindrical protrusion 49 with a through-hole such as a vertical slit 49a. That is, even if the first cylindrical protrusion 49 is not provided with a through hole, the swirling flow of the secondary combustion air can be divided into the descending swirl flow and the ascending swirl flow.

The primary combustion unit 4 is provided with an ignition unit 7 that ignites the fuel when the burner is started. The ignition part 7 is disposed in the casing 71, a rectangular tubular casing 71 that passes through and is fixed to the first outer cylinder 41 and the first inner cylinder 42, a fuel injection nozzle 72 that is disposed in the casing 71, and the casing 71. And a spark plug 73. The fuel injection nozzle 72 is supplied with kerosene as ignition fuel at a pressure of ² to 3 kg / cm ² and injects it from a nozzle provided at the tip. The spark plug 73 is applied with a voltage of several thousand to 10,000 volts, generates a spark by electric discharge between the tip electrode and the casing, and ignites the sprayed kerosene. The spark plug 73 may be one having two electrodes, ie, a center electrode and a ground electrode, without using the casing 71 as a ground electrode. An air supply pipe 74 that supplies combustion air at the time of ignition is connected to a portion of the casing 71 outside the first outer cylinder 41. The ignition unit 7 is fixed so as to be inclined downward toward the center of the first inner cylinder 42 so that the nozzle of the fuel injection nozzle 72 and the electrode of the spark plug 73 are directed to the fuel on the fuel holding unit 33. Is arranged.

  A maintenance opening (not shown) is provided at the lower part of the primary combustion unit 4. The maintenance opening is formed by a rectangular through hole provided at the same radial position in the first outer cylinder 41 and the first inner cylinder 42. The maintenance opening is closed with a double-structured closure lid having an outer lid that fits into the through hole of the first outer cylinder 41 and an inner lid that fits into the through hole of the first inner cylinder 42. An air passage through which a swirling flow of secondary combustion air can flow is provided between the outer lid and the inner lid. A maintenance opening is opened after the burner 1 is operated to remove metal debris contained in the fuel and ash remaining after combustion.

  The secondary combustion unit 5 includes a cylindrical second outer cylinder 51 having a smaller diameter than the outer cylinder 41 of the primary combustion unit 4, and a cylindrical second inner cylinder disposed inside the second outer cylinder 51. A cylinder 52 is provided. At the lower part of the second outer cylinder 51, a tertiary air introduction port 51a for introducing tertiary combustion air in the tangential direction is provided. A flange-shaped flange 51 b is provided at the lower end of the second outer cylinder 51, and the flange 51 b is fixed to the first partition plate 44. An annular second partition plate 54 is fixed to the upper end of the second outer cylinder 51. The second inner cylinder 52 is attached to the first partition plate 44.

  FIG. 3 is an exploded perspective view showing how the second inner cylinder 52 is attached to the first partition plate 44. An annular locking ring 53 is fixed to the outer peripheral surface of the second inner cylinder 52 at a position spaced a predetermined distance upward from the lower end. The lower end portion of the second inner cylinder 52 is fitted into the opening 44 a of the annular first partition plate 44, the locking ring 53 is locked to the upper side surface of the first partition plate 44, and the second inner cylinder 52 is It is attached to the first partition plate 44. When the second inner cylinder 52 is attached to the first partition plate 44, the lower end portion of the second inner cylinder 52 protrudes by a predetermined length from the lower surface of the first partition plate 44. The protruding lower end portion of the second inner cylinder 52 functions as a first diversion portion (first cylindrical protrusion 49) of the primary combustion portion 4. It should be noted that the vertical fixing position of the annular locking ring 53 with respect to the second inner cylinder 52 can be adjusted, and the second inner cylinder 52 is viewed from the lower side when the second inner cylinder 52 is attached to the first partition plate 44. The amount by which the lower end of the first protrusion protrudes may be adjustable, and the vertical length of the first cylindrical protrusion 49 may be adjustable. Thereby, the ratio which the 1st cylindrical protrusion 49 divides combustion air into an upward swirl flow and a downward swirl flow can be adjusted suitably. The vertical fixing position of the locking ring 53 with respect to the second inner cylinder 52 is determined by threading the inner circumferential surface of the locking ring 53 and the outer circumferential surface of the second inner cylinder 52 and screwing them together. The retaining ring 53 can be adjusted by rotating with respect to the second inner cylinder 52.

  In addition, since the second inner cylinder 52 is detachably formed on the first partition plate 44, when the combustion temperature of the second combustion chamber 57 becomes high and the deterioration of the second inner cylinder 52 proceeds, the second The inner cylinder 52 can be easily replaced.

  A spiral projection 55 formed by spirally winding a plate material is fixed to the outer peripheral surface of the second inner cylinder 52. A cylindrical annular second preheating chamber 56 is formed between the outer peripheral surface of the second inner cylinder 52 provided with the spiral protrusion 55 and the inner peripheral surface of the second outer cylinder 51 as shown in FIG. Yes. By introducing the tertiary combustion air into the second preheating chamber 56 in the tangential direction from the tertiary air introduction port 51a, a swirling flow of the combustion air from the lower part to the upper part is formed. A second combustion chamber 57 is formed inside the second inner cylinder 52. The second inner cylinder 52 is formed to be lower than the second outer cylinder 51, and the upper end of the second inner cylinder 52 is separated from the lower surface of the second partition plate 54 by a predetermined distance. A second communication portion 58 that connects the second preheating chamber 56 and the second combustion chamber 57 is formed between the lower surface of the second partition plate 54 and the upper end of the second inner cylinder 52. In the second communication portion 58, a second cylindrical projection 59 as a second diversion portion protrudes downward from the opening of the annular second partition plate 54. The second cylindrical protrusion 59 is formed integrally with the exhaust cylinder 6, and the lower end of the exhaust cylinder 6 is the second cylindrical protrusion 59.

  Similar to the first cylindrical protrusion 49, the second cylindrical protrusion 59 is formed with a plurality of vertical slits 59 a as through holes. By this vertical slit 59a, the swirling flow of the tertiary combustion air from the second preheating chamber 56 is divided at an appropriate ratio between the descending swirling flow and the rising swirling flow. The through hole of the second cylindrical protrusion 59 is not limited to the vertical slit 59a, but may be an inclined slit similar to FIG. 2A, a horizontal slit similar to FIG. 2B, or a round hole similar to FIG. 2C. Good. However, it is not always necessary to provide the second cylindrical projection 59 with a through hole such as a vertical slit 59a.

  The second outer cylinder 51 of the secondary combustion unit 5 is formed smaller in both the axial dimension and the diameter than the first outer cylinder 41 of the primary combustion unit 4. Further, the second inner cylinder 52 of the secondary combustion unit 5 is formed smaller in both axial dimension and diameter than the first inner cylinder 42 of the primary combustion unit 4.

  The exhaust cylinder 6 has a smaller diameter than that of the second inner cylinder 52 of the secondary combustion section 5, and an annular locking is provided on the outer peripheral surface of the exhaust cylinder 6 at a position spaced a predetermined distance upward from the lower end. The ring 63 is fixed. By fitting the lower end portion of the exhaust pipe 6 into the opening of the annular second partition plate 54 and locking the locking ring 63 on the upper side surface of the second partition plate 54, the exhaust pipe 6 is connected to the second partition plate. 54. When the exhaust tube 6 is attached to the second partition plate 54, the lower end portion of the exhaust tube 6 protrudes by a predetermined length from the lower surface of the second partition plate 54. The protruding lower end portion of the exhaust cylinder 6 functions as a second diversion portion (second cylindrical protrusion 59) of the secondary combustion portion 5. As in the case of the second inner cylinder 52, the vertical fixing position of the annular locking ring 63 with respect to the exhaust cylinder 6 can be adjusted, and the lower position when the exhaust cylinder 6 is attached to the second partition plate 54. The amount by which the lower end portion of the exhaust tube 6 protrudes from the side surface may be adjustable, and the vertical length of the second cylindrical protrusion 59 may be adjustable.

  The burner 1 of this embodiment operates as follows. First, the fuel supplier 2 is activated, and a predetermined amount of wood pellets 8 is discharged from a hopper (not shown) by a supply valve 21. The wood pellets 8 are first combusted by the first screw conveyor 22 and the second screw conveyor 23. It is transferred into the chamber 47. The wood pellets 8 transported into the first combustion chamber 47 are discharged from the fuel supply port 24 and are accumulated from the fuel supply port 24 to the mortar portion 33a of the fuel holding unit 33. When a predetermined amount of wood pellets 8 is supplied into the first combustion chamber 47, the ignition unit 7 is operated to inject kerosene from the fuel injection nozzle 72 toward the wood pellets 8 and to apply a voltage to the spark plug 73. To ignite the wood pellet 8. In addition, a blower (not shown) is activated to the primary air inlet 32 of the lower preheating unit 3, the secondary air inlet 41 a of the primary combustion unit 4, and the tertiary air inlet 51 a of the secondary combustion unit 5. Supply combustion air. Further, auxiliary combustion air is supplied from the blower to the air supply pipe 25 of the first screw conveyor 22. These total combustion air amounts are set to about 1: 1.5 in terms of the fuel air ratio.

  In the lower preheating unit 3, the primary combustion air is introduced from the primary air introduction port 32 in the tangential direction of the outer peripheral surface of the casing 31 (arrow F 0), and the swirling flow of the primary combustion air (arrow F 1) is introduced into the casing 31. Generate. This swirling flow of the primary combustion air is guided to the communication path between the outer peripheral surface of the tip portion of the second screw conveyor 23 and the inner peripheral surface of the sleeve-shaped portion 33b of the fuel holding portion 33 (arrow F2). The swirling flow of the primary combustion air that has passed through the communication path is blown into the first combustion chamber 47 from the air outlet 34.

  In the primary combustion section 4, the secondary combustion air is introduced from the secondary air introduction port 41 a in the tangential direction of the first outer cylinder 41 (arrow F <b> 10), thereby moving from the lower part to the upper part in the first preheating chamber 46. A swirling flow (arrow F11) of secondary combustion air is generated. The secondary combustion air passing through the first preheating chamber 46 is preheated by receiving heat from the first combustion chamber 47 via the first inner cylinder 42 and the spiral protrusion 45. By flowing the secondary combustion air into the first preheating chamber 46 in a swirling manner, the residence time in the first preheating chamber 46 can be secured and sufficiently preheated. Further, the spiral protrusion 45 can increase the heat radiation area to further improve the preheating efficiency of the secondary combustion air, and can rectify the flow of the secondary combustion air in a swirling manner. The spiral protrusion 45 may not be installed.

  FIG. 4A is a schematic diagram showing the flow of secondary combustion air in the preheating chamber 49 and the first communication portion 48 of the primary combustion section 4, and FIG. 4B is the secondary combustion air and combustion in the first combustion chamber 47. It is the schematic diagram which showed the flow of gas. As shown in FIGS. 1 and 4A, the swirling flow of the secondary combustion air that has been preheated and reaches the first communicating portion 48 in the upper portion of the first outer cylinder 41 is swung downward by the first cylindrical protrusion 49. It is divided into a flow and a rising swirl flow. In detail, it flows along the outer peripheral surface of the first cylindrical protrusion 49 and flows downward (arrow F12) toward the lower part of the first combustion chamber 47, and passes through the vertical slit 49a of the first cylindrical protrusion 49. Then, the flow is divided into an upward swirling flow (arrow F13) flowing upward inside the first cylindrical protrusion 49. The downward swirling flow divided by the first cylindrical protrusion 49 flows downward in the outer diameter portion of the first combustion chamber 47 and reaches the vicinity of the wood pellet 8 of the lower fuel holding portion 33. In this way, in the first combustion chamber 47, the first combustion air is supplied from the air outlet 34 and the preheated secondary combustion air is supplied downward from above, so that the wood on the fuel holding portion 33 The pellets 8 can be burned at a high temperature and efficiently decomposed.

  Further, the auxiliary combustion air introduced into the air supply pipe 25 is supplied into the first combustion chamber 47 from the fuel supply port 24 via the first and second screw conveyors 22 and 23, whereby the combustion in the first combustion chamber 47 is performed. The amount of air can be further increased. Further, by introducing auxiliary combustion air into the air supply pipe 25, even if the pressure in the first combustion chamber 47 rises due to combustion, the inflow of combustion gas into the screw conveyors 22 and 23, and the wood pellet 8 Inconveniences such as backflow can be prevented.

  In this way, the first combustion chamber 47 in which the combustion air is preheated and supplied in a swirling shape from the up and down direction can burn the wood pellets 8 as fuel at a stable temperature. Gasified fuel is generated as the wood pellet 8 is pyrolyzed, and the combustion gas containing a large amount of gasified fuel flows in a swirling manner upward along the inner diameter of the first combustion chamber 47, as indicated by an arrow F14. . The upward swirling flow is not limited to gasified fuel, but also includes fine particles of the wood pellet 8 in the pyrolysis process and oxides of the gasified fuel.

  The combustion gas containing a large amount of gasified fuel rises while forming a swirling flow, and flows into the second combustion chamber 57 of the secondary combustion unit 5 through the first communication unit 48.

  FIG. 4C is a schematic diagram showing the flow of combustion air and combustion gas in the second combustion chamber 57 of the secondary combustion unit 5. In the second combustion chamber 57, a swirling flow of combustion gas directed upward flows in the inner diameter portion (arrow F24), and the secondary combustion air that has passed through the vertical slit 49a of the first cylindrical protrusion 49 in the outer diameter portion. Upward swirling flow (arrow F13) flows in.

  Further, in the secondary combustion section 5, by introducing the tertiary combustion air from the tertiary air introduction port 51a in the tangential direction of the second outer cylinder 51 (arrow F20), the second preheating chamber 56 is moved from the lower part to the upper part. The swirling flow (arrow F21) of the third combustion air toward The tertiary combustion air passing through the second preheating chamber 56 is preheated by receiving heat from the second combustion chamber 57 via the second inner cylinder 52 and the spiral protrusion 55. Similar to the primary combustion unit 4, the third combustion air is swirled into the second preheating chamber 56, so that the residence time in the second preheating chamber 56 can be secured and sufficiently preheated. Further, the spiral protrusion 55 can increase the heat radiation area to further improve the preheating efficiency of the tertiary combustion air, and can rectify the tertiary combustion air in a swirling manner.

  The swirling flow of the tertiary combustion air that has been preheated and has reached the upper second communication portion 58 in the second outer cylinder 51 is split into a descending swirling flow and an ascending swirling flow by the second cylindrical projection 59. In detail, it flows along the outer peripheral surface of the second cylindrical protrusion 59 and passes through the downward swirling flow (arrow F22) toward the lower part in the second combustion chamber 57 and the vertical slit 59a of the second cylindrical protrusion 59. Then, the flow is divided into an upward swirling flow (arrow F23) that flows upward inside the exhaust tube 6. The downward swirling flow of the tertiary combustion air divided by the second cylindrical protrusion 59 flows downward in the outer diameter portion of the second combustion chamber 57.

  As described above, the second combustion chamber 57 is supplied with the sufficiently preheated secondary combustion air from the lower part upward (arrow F13) and the sufficiently preheated tertiary combustion air is supplied from the upper part downward (arrow F22). Therefore, the gasified fuel obtained by pyrolyzing the wood pellet 8 in the primary combustion unit 4 can be efficiently oxidized at a high temperature. Further, the fine particles of the fuel remaining in the combustion gas can be efficiently decomposed and oxidized. In this way, the wood pellets 8 can be completely burned through the combustion process by the primary and secondary combustion sections 4 and 5. Thus, by burning the wood pellets in the two-stage combustion sections 4 and 5, a combustion temperature of 900 ° C. to 1000 ° C. can be generated in the vicinity of the upper end of the second combustion chamber 57.

  Combustion gas in which most combustible components combust in the second combustion chamber 57 flows into the exhaust pipe 6 through the second communication portion 58. The ascending swirl flow divided by the second cylindrical protrusion 59 flows into the exhaust cylinder 6, and the combustion gas is efficiently discharged by the ascending swirl flow.

  As described above, according to the burner of the present embodiment, the primary combustion air is supplied to the first combustion chamber 47 in a swirling manner from the lower portion, and the descending swirling flow of the preheated secondary combustion air is supplied from the upper portion. Thereby, thermal decomposition of the wood pellet 8 can be performed with high efficiency. Further, the wood pellet 8 is thermally decomposed by supplying the second combustion chamber 57 with the upward swirling flow of the preheated secondary combustion air from the lower portion and the lower combustion flow of the preheated tertiary combustion air from the upper portion. The gasified fuel produced by the above can be highly oxidized. Therefore, even a polymer component such as lignin contained in a plant regenerated fuel can be effectively thermally decomposed and oxidized to be completely burned. As a result, the generation amount of ash and soot can be significantly reduced as compared with the prior art. In addition, in each part of the lower preheating part 3, the primary combustion part 4, the secondary combustion part 5, and the exhaust pipe 6, the size of each part is increased by flowing the combustion air and the combustion gas in a swirling manner. Therefore, the residence time of the combustion air and combustion gas can be extended, so that the preheating efficiency of the combustion air and the combustion efficiency of the fuel can be improved without increasing the size of the burner. That is, it is possible to realize a burner that can completely burn plant regenerated fuel and the like, and has a small amount of smoke emission while being small.

  In the burner 1 of the present embodiment, the pressure rises as the combustion temperature in the first combustion chamber 47 rises, but a screw blade missing portion is provided in the middle of the first screw conveyor 22 to make the wood pellet 8 Therefore, the backflow of the wood pellet 8 and the backflow of the combustion gas can be prevented with a simple structure.

  Moreover, the burner 1 of this embodiment can detect the heat | fever conducted from the 1st combustion chamber 47 to the 1st screw conveyor 22 with the temperature sensor 27, and can cope with the abnormal rise of the combustion temperature of the 1st combustion chamber 47. it can. That is, when the combustion temperature in the first combustion chamber 47 abnormally rises and the detection value of the temperature sensor 27 exceeds a predetermined temperature, the flow control valve 29 is opened by the control of the control unit 28 and the first water supply pipe 26 is operated. Water is supplied to the screw conveyor 22. Thereby, the temperature in the 1st combustion chamber 47 can be reduced effectively, and abnormal combustion can be stopped rapidly. In addition to detecting the temperature of the first screw conveyor 22, the temperature of the first inner cylinder 42 defining the first combustion chamber 47 and the temperature of the first outer cylinder 41 may be detected. Alternatively, the temperature of the second inner cylinder 52 that partitions the second combustion chamber 57 and the temperature of the second outer cylinder 51 may be detected.

  Moreover, in the burner 1 of this embodiment, the 1st screw conveyor 22 which conveys the wood chip | tip 8 to the fuel supply device 2 for supplying continuously the wood chip | tip 8 as a fuel, and the wood chip | tip 8 are made into the 1st combustion chamber 47. However, a single screw conveyor can be used. For example, a screw conveyor similar to the first screw conveyor 22 in FIG. 1 may be used in which a supply head 120 as shown in FIG. In this screw conveyor, as shown in FIG. 5A, the tip portion of the casing 121 is curved, and the flange 121a provided at the tip is oriented in a direction substantially perpendicular to the extending direction of the straight portion. FIG. 5B is a plan view of the supply head 120. The curved portion of the casing 121 is provided with a bearing portion 121b of the rotating shaft 122 that rotationally drives the screw blades 123 arranged in the linear portion. An air supply port 121c is formed through the flange 121a at the tip of the casing 121, and an annular and hollow air distribution duct 125 communicating with the air supply port 121c is fixed to the upper surface of the flange 121a. The opening on the inner peripheral side of the air distribution duct 125 is continuous with the inner peripheral surface of the casing 121 of the screw conveyor, and serves as a fuel supply port 124 for discharging the wood chip 8 into the first combustion chamber 47. In the air distribution duct 125, a first slit 125a extending in the axial direction is formed on the inner peripheral surface, and a second slit 125b extending in the radial direction and the axial direction is formed on the upper end surface and the inner peripheral surface. The upper end surface portion of the second slit 125 b extends while being inclined with respect to the radial direction of the air distribution duct 125. By supplying the primary combustion air to the air supply port 121c, the primary combustion air supplied from the air supply port 121c into the air distribution duct 125 is blown out in a swirling manner from the second slit 125b. . That is, when the screw conveyor having the supply head 120 is used, the primary combustion air can be directly supplied from the blower to the air supply port 121c and blown out from the second slit 125b. Can be deleted.

  A fuel diffusion member 127 is attached to the supply head 120 of the screw conveyor so as to surround the outer peripheral portion and the outer peripheral surface of the upper end surface of the air distribution duct 125. The fuel diffusion member 127 has a substantially cylindrical shape, and the inner peripheral surface of the upper end portion is formed on an inclined surface 127a that is inclined so as to be directed toward the inner diameter side as it goes downward. An inclined surface 127 a of the fuel diffusion member 127 is disposed so as to surround the outer peripheral side of the second slit 125 b of the air distribution duct 125. A plurality of teeth 127b projecting in the axial direction are arranged in the circumferential direction at the lower end portion of the fuel diffusion member 127, and a drive unit that rotationally drives the fuel diffusion member 127 below the lower end portion of the fuel diffusion member 127 128 is arranged. The drive unit 128 is formed of a rotary shaft 128a that is rotationally driven and an eccentric rotary body 128b that is fixed to the rotary shaft 128a. As the rotating shaft 128a rotates, the tip of the arm of the eccentric rotating body 128b is sequentially engaged with the teeth 127b of the fuel diffusing member 127 so that the fuel diffusing member 127 is rotated in the circumferential direction. With the rotation of the fuel diffusion member 127, the wood chip 8 discharged from the fuel supply port 124 on the inner peripheral side of the air distribution duct 125 is diffused to the outer diameter side of the fuel diffusion member 127. By using the screw conveyor having the supply head 120 for the fuel supply device 2, the lower preheating unit 3 can be eliminated to further reduce the size of the burner. Moreover, the 2nd screw conveyor 23 of FIG. 1 can be deleted, and the dimension of an up-down direction can be shortened.

  The burner 1 of this embodiment can be used as a heat source of a horizontal steam boiler 110 as shown in FIG. The steam boiler 110 includes a casing 111, a plurality of smoke pipes 112 arranged in the horizontal direction in the casing, and tube plates 113 and 113 that support both end portions of the smoke pipe 112 and form a steam chamber inside. A water supply port 114 for supplying water into the steam chamber and a discharge port 115 for discharging the steam in the steam chamber are provided. The exhaust pipe 6 of the burner 1 is connected to one end of the casing 111, and the combustion gas dust collector 116 is connected to the other end of the casing 111. A sirocco blower 9 that supplies combustion air to the lower preheating unit 3, the primary combustion unit 4, and the secondary combustion unit 5 is connected to the burner 1 via a branch pipe 91. Further, auxiliary combustion air is supplied from the blower 9 to the air supply pipe 25 of the first screw conveyor 22 through the flow dividing pipe 91. The steam boiler 110 is a three-pass boiler in which the direction in which the combustion gas flows in the casing 111 is reversed at two locations. That is, high-temperature combustion gas is supplied from the burner 1 to one end of the casing 111 (arrow G1), and the combustion gas flows after exchanging heat with steam (or water) in the steam chamber through the first group of smoke pipes 112. Is reversed (arrow G2), and after the heat exchange with the steam (or water) through the second group of smoke pipes 112, the flow is reversed again (arrow G3), and the steam ( Or, after exchanging heat with water, it is discharged from the casing 111 (arrow G4). The combustion gas discharged from the casing 111 is collected by the dust collector 116 and released to the atmosphere. As the dust collector 116, a filter type, electrostatic type or cyclone type dust collector can be used.

  The burner 1 of the above embodiment includes a temperature sensor 61 that detects the temperature of the combustion gas discharged from the exhaust pipe 6, a first inverter 117 that controls the power supplied to the drive motor M of the fuel supplier 2, and the blower 9 A second inverter 118 that controls the power supplied to the drive motor, and a control unit 119 that receives the output from the temperature sensor 61 and controls the switching speed of each of the inverters 117 and 118 based on the detected value of the temperature sensor 61; Is provided. By this control unit 119, the temperature of the combustion gas can be stably controlled to a predetermined temperature, and the temperature of the steam discharged from the discharge port 115 of the steam boiler 110 can be stably set to the predetermined temperature.

  That is, when the combustion gas temperature detected by the temperature sensor 61 is lower than the target value, the control unit 119 outputs a control signal C1 corresponding to the difference from the target value of the combustion gas temperature to the first inverter 117. Thereby, the rotation speed of the motor M that drives each of the supply valve 21, the first screw conveyor 22, and the second screw conveyor 23 of the fuel supplier 2 is increased, and the wood pellet 8 is supplied to the first combustion chamber 47. Increase the amount. At the same time, the control unit 119 outputs a control signal C2 corresponding to the difference from the target value of the combustion gas temperature to the second inverter 118. Thereby, the rotation speed of the motor which drives a blower is increased, and the flow volume of the combustion air supplied to the lower preheating part 3, the primary combustion part 4, and the secondary combustion part 5 is increased. In this way, the combustion amount of the wood pellet 8 can be increased, and the combustion gas temperature can be raised to approach the target value.

  On the other hand, when the combustion gas temperature detected by the temperature sensor 61 is higher than the target value, the control unit 119 outputs a control signal C1 corresponding to the difference from the target value of the combustion gas temperature to the first inverter 117. Thereby, the number of rotations of the motor M that drives each part of the fuel supplier 2 is decreased, and the amount of the wood pellets 8 supplied to the first combustion chamber 47 is reduced. At the same time, the control unit 119 outputs a control signal C2 corresponding to the difference from the target value of the combustion gas temperature to the second inverter 118. Thereby, the rotation speed of the motor that drives the blower is decreased, and the flow rate of the combustion air supplied to the lower preheating unit 3, the primary combustion unit 4, and the secondary combustion unit 5 is decreased. Thus, the combustion amount of the wood pellet 8 can be reduced, and the combustion gas temperature can be lowered to approach the target value.

  As described above, the control unit 119 performs feedback control based on the combustion gas temperature, thereby maintaining the temperature of the combustion gas at a predetermined target value, and the temperature of the steam discharged from the discharge port 115 of the steam boiler 110. Can be stably set to a predetermined temperature. Note that the temperature sensor may be disposed in the outer cylinders 41 and 51 and the inner cylinders 42 and 52 of the combustion units 4 and 5 in addition to the exhaust cylinder 6. Further, a temperature sensor may be provided at the discharge port 115 of the steam boiler 110, and the supply amount of the wood pellet 8 and the flow rate of the combustion air may be controlled by the control unit 119 based on the temperature of the steam detected by the temperature sensor. .

  Further, the control unit 119 limits the rotation speed of the drive motor of the fuel supply device 2 to a predetermined low rotation speed and sets the rotation speed of the blower drive motor to a predetermined value for a predetermined period from the start of the burner 1. It is preferable to perform the start-up operation while limiting to a low rotational speed. Thereafter, when the operation time of the burner 1 exceeds a predetermined time from the startup, feedback control based on the output of the temperature sensor 61 is performed. Further, as the stop signal of the burner 1 is received, the feedback control is stopped, the rotation speed of the drive motor of the fuel supply device 2 is limited to a predetermined low rotation speed, and the rotation speed of the drive motor of the blower is predetermined. It is preferable to perform the stop operation while limiting to a low rotational speed. In this way, by supplying a relatively small amount of predetermined fuel and amount of combustion air at the time of start-up, even when using vegetable regenerated fuel that is relatively difficult to ignite, it is possible to reliably ignite the fuel and burn the burner. Can be activated. In addition, when the fuel is stopped, the fuel combustion can be reliably stopped by supplying a relatively small amount of fuel and a predetermined amount of combustion air.

  Since the burner 1 of the present embodiment can completely burn the wood pellets 8 as fuel, the amount of soot contained in the combustion gas is smaller than that in the prior art. Therefore, since the amount of soot remaining in the casing 111 and the smoke pipe 112 of the steam boiler 110 can be reduced, the maintenance frequency for removing soot can be reduced as compared with the conventional case, and the running cost can be reduced. Further, it is possible to prevent the steam boiler 110 from being deteriorated due to residual soot. Further, since the amount of soot contained in the combustion gas of the burner 1 is small, a small-capacity dust collector 116 can be used, and the cost reduction and downsizing of peripheral equipment of the steam boiler 110 can be achieved.

  By the way, the burner 1 of this embodiment is used as a heat source such as a one-pass boiler in which combustion gas flows in a single direction in a casing, or a two-pass boiler in which the direction of combustion gas flow is reversed at one place. You can also Moreover, it can also be used for the water pipe boiler which has arrange | positioned the water pipe in the heating chamber to which combustion gas is supplied besides the smoke pipe boiler which flows combustion gas into a smoke pipe. Moreover, it can also be used for the vertical boiler which has arrange | positioned the smoke pipe or water pipe which performs heat exchange in the perpendicular direction. Moreover, you may use the burner 1 of this embodiment not only for a steam boiler but for the heat source of the hot water boiler which produces | generates warm water. Furthermore, the burner 1 of this embodiment can be widely used as a heat source for a hot air device, a refrigerator, etc., in addition to a boiler. In any application, it is possible to realize a thermal apparatus that is small and highly efficient and easy to maintain.

  The burner 1 of the present embodiment can widely use fuel other than the wood chip 8, for example, wood waste, bark, plastic waste, rubber waste or RPF (waste paper / waste plastic solid fuel) or the like as fuel. Can be used. According to the burner 1 of the present embodiment, any fuel can be completely combusted, and high combustion efficiency can be obtained with less dust emission than conventional. In addition, when using plastic waste, rubber waste, RPF, etc. for fuel, it is preferable to use a three-stage burner provided with a tertiary combustion section in addition to the primary and secondary combustion sections 4 and 5. That is, a third outer cylinder that is substantially similar to the second outer cylinder 51 and small in size is fixed to the second partition plate 54 of FIG. Fit the inner cylinder. A third partition plate, which is substantially similar to the second partition plate 54, is fixed to the upper end of the third outer cylinder, and a small exhaust tube, which is approximately similar to the exhaust cylinder 6, is fixed to the opening of the third partition plate. . Thus, a third combustion chamber is formed inside the third inner cylinder, and a third preheating chamber is formed on the outer peripheral side of the third combustion chamber. Ascending swirling flow of the tertiary combustion air (arrow F23) is supplied to the third combustion chamber, and the quaternary combustion air preheated in the third preheating chamber is divided at the lower end portion of the exhaust pipe, and is divided. A downward swirling flow of air is supplied to the third combustion chamber. Thus, by burning in multistage combustion chambers, fuel such as plastic waste can be completely burned. Further, four or more stages of combustion chambers and preheating chambers may be provided depending on the type of fuel.

  The fuel of the burner 1 is not limited to burning a single fuel, and a plurality of fuels may be burned continuously. In this case, the amount of combustion air may be appropriately adjusted according to the oxidation temperature of the fuel. A plurality of fuels may be burned simultaneously. It is also possible to burn a multiphase fuel composed of a solid fuel and a liquid fuel.

  Moreover, the blower which supplies combustion air to the lower preheating part 3 of the burner 1, the primary combustion part 4, the secondary combustion part 5, and the supply pipe 25 of the 1st screw conveyor 22 may not be single, but each supply You may install a blower separately previously. By controlling the blower volume of the blower installed individually based on the combustion temperature of the combustion chamber of each supply destination, the combustion temperature of the combustion chamber of each stage can be finely adjusted, and the combustion efficiency can be further improved. .

  Further, oxygen may be supplied together with combustion air to at least one of the lower preheating unit 3, the primary combustion unit 4, the secondary combustion unit 5, and the air supply pipe 25 of the first screw conveyor 22. The combustion air having a high oxygen concentration can further promote complete combustion and can further increase the combustion temperature.

  Moreover, you may supply mist-like water to the 1st combustion chamber 47 of the primary combustion part which is the lowest stage. The mist-like water supplied to the first combustion chamber 47 reacts with carbon contained in the fuel in the first combustion chamber 47 to generate carbon monoxide and hydrogen. Thereby, the combustion temperature in the 1st combustion chamber 47 can further be raised. Further, the atomized water is thermally decomposed at the temperature of the first combustion chamber 47 to generate hydrogen and oxygen. Thereby, the combustion temperature in the 1st combustion chamber 47 can further be raised. As the water supply device, a plunger pump that applies a pressure of about 2 MPa (megapascal) to water, a high-pressure water supply passage that supplies this high-pressure water from the plunger pump to the first combustion chamber 47, and a connection to this high-pressure water supply passage And an injection nozzle that injects mist-like water into the first combustion chamber 47.

  In the present embodiment, the vertical direction coincides with the direction in which gravity acts, and the axes of the first and second inner cylinders 42 and 52 and the outer cylinders 41 and 51 of the burner 1 are oriented in the vertical direction. The burner 1 can be used with the axis inclined with respect to the vertical direction, and can also be used with the axis directed in a substantially horizontal direction.

  Moreover, the primary combustion part 4 and the secondary combustion part 5 do not necessarily need to be formed linearly, and may be formed by curving one of them. For example, as shown in the modification of FIG. 7, the axis of the primary combustion unit 4 of the burner 100 is oriented in the vertical direction, while the secondary combustion unit 150 is curved and the axis of the exhaust stack 6 is oriented in the horizontal direction. Also good. In this case, the inner cylinder 152 may be bent by 90 ° together with the outer cylinder 151 of the secondary combustion unit 150. 7 is used as a heat source for a one-pass hot water boiler 130. In FIG. 7, 131 is a casing in which combustion gas is guided to the inside to form a heating chamber, 132 is a water supply port to which water to be heated is supplied, and 133 is water that is supplied from the water supply port 132 to guide the combustion gas. A water pipe for performing heat exchange, 134 is a discharge port for discharging water that has been subjected to heat exchange and having a high temperature, and 135 is an exhaust pipe for discharging combustion gas after heat exchange. According to the burner 100 of this modification, the vertical dimension can be reduced, and a small hot water boiler 130 can be configured.

  FIG. 8 is a view showing a burner according to another embodiment. This burner 200 is used to incinerate PCB (polychlorinated biphenyl) waste liquid. FIG. 8 shows a part of the burner 200, and the other parts are substantially the same as the burner 1 of FIG. Components that are substantially the same as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The burner 200 supplies only the secondary combustion air preheated in the first preheating chamber 46 without supplying the primary combustion air to the first combustion chamber 247. The first inner cylinder 242 that defines the side surface of the first combustion chamber 247 is made of ceramic having high heat resistance. The PCB liquid stored in the PCB tank 243 is sucked by the pump 245 through the strainer 244 and is supplied to the first combustion chamber 247 from the supply port 246 formed on the side surface of the first inner cylinder 242. Has been. At the bottom of the first combustion chamber 247, an evaporating dish 240 formed in an inverted truncated cone shape is provided. The burner 200 receives PCB liquid supplied from the PCB tank 243 into the first combustion chamber 247 by the evaporating dish 240, and swirls the secondary combustion air passing through the first preheating chamber 46 in the first combustion chamber 247. The PCB liquid is evaporated and thermally decomposed. The PCB gas which has been evaporated and thermally decomposed is guided to the upper second combustion chamber 57 through the first communication portion 48, and in this second combustion chamber 57, the secondary combustion air supplied from the lower part and the tertiary combustion supplied from the upper part are provided. Oxidizes with air. The second inner cylinder 252 that defines the side surface of the second combustion chamber 57 is formed of ceramic having high heat resistance. By preheating a large amount of combustion air into the first combustion chamber 247 and the second combustion chamber 57 and supplying them in a swirling manner, a combustion temperature of 1100 ° C. to 1300 ° C. is stably generated to completely burn the PCB. be able to. Thereby, a PCB waste liquid can be incinerated and a detoxification process can be performed. Note that oxygen may be supplied to the first combustion chamber 247 and the second combustion chamber 57 together with the combustion air. By supplying combustion air having a high oxygen concentration, complete combustion of the PCB can be promoted to a higher degree.

  The burner of the present invention can be widely used as a heat source for heat equipment such as a steam boiler, a hot water boiler, a hot air device, and a refrigerator. Moreover, it can be used as an incinerator burner for incinerating hardly decomposable substances.

It is sectional drawing which shows the burner of embodiment of this invention. It is a model expanded view of the 1st cylindrical protrusion provided with the through hole. It is a model expanded view of the 1st cylindrical protrusion provided with the other through-hole. It is a model expanded view of the 1st cylindrical protrusion provided with the other through-hole. It is a disassembled perspective view which shows a mode that the 2nd inner cylinder of a secondary combustion part is attached to a 1st partition plate. It is the schematic diagram which showed the flow of the secondary combustion air in the preheating chamber of a primary combustion part, and a 1st communication part. It is the schematic diagram which showed the flow of the secondary combustion air and combustion gas in the 1st combustion chamber of a primary combustion part. It is the schematic diagram which showed the flow of the combustion air and combustion gas in the 2nd combustion chamber of a secondary combustion part. It is a figure which shows the supply head formed integrally with the screw conveyor. It is a top view of a supply head. It is a fragmentary sectional view showing the steam boiler which used the burner of this embodiment for the heat source. It is a figure which shows a mode that the burner of the modification was applied to the hot water boiler. It is a figure which shows the burner of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Burner 2 Fuel supply device 3 Lower preheating part 4 Primary combustion part 5 Secondary combustion part 6 Exhaust pipe 7 Ignition part 8 Wood pellet 21 Supply valve 22 1st screw conveyor 23 2nd screw conveyor 24 Fuel supply port 32 Primary air Inlet 33 Fuel holder 41 First outer cylinder 41a Secondary air inlet 42 First inner cylinder 44 First partition plate 45 Spiral projection 46 First preheating chamber 47 First combustion chamber 48 First communication portion 49 First cylindrical shape Projection 49a Vertical slit 51 Second outer cylinder 52 Second inner cylinder 54 Second partition plate 55 Spiral projection 56 Second preheating chamber 57 Second combustion chamber 58 Second communication portion 59 Second cylindrical projection 59a Vertical slit

Claims (14)

A cylindrical combustion chamber; a cylindrical annular preheating chamber that is formed so as to surround the combustion chamber and that preheats combustion air; and a communication portion that connects the upper portion of the combustion chamber and the upper portion of the preheating chamber. With multiple stages of combustion,
The preheating chamber of the combustion part is formed so that the combustion air supplied from the lower part flows in a swirling manner toward the upper part,
The communication part of the combustion part has a flow dividing part that divides the swirling flow of the combustion air preheated in the preheating chamber into a downward swirling flow toward the lower portion of the combustion chamber and an upward swirling flow toward the upper side of the combustion chamber. Have
Combustion chambers in the second and subsequent stages of combustion include an upward swirling flow of combustion air diverted by a diversion part of the preceding combustion part and a downward swirling flow of combustion air diverted by the diversion part of the combustion part of the same stage Is provided to burn the fuel. The burner according to claim 1, wherein
A burner characterized in that the combustion chamber of each stage combustion section is formed with a smaller diameter than the combustion chamber of the preceding combustion section. The burner according to claim 1, wherein
A burner comprising a fuel supply device that continuously supplies fuel to a combustion chamber of a lowermost combustion section. The burner according to claim 1, wherein
A burner comprising a blower for supplying combustion air to the preheating chamber of the combustion section of each stage. The burner according to claim 1, wherein
The diverter includes a cylindrical protrusion that protrudes downward from an upper wall surface that defines the communication portion. Burner according to claim 5,
The said cylindrical protrusion has a some through-hole, The burner characterized by the above-mentioned. The burner according to claim 1, wherein
The burner characterized in that the cylindrical protrusion is formed integrally with a lower end side of a cylindrical member that divides a subsequent combustion chamber and a preheating chamber. The burner according to claim 1, wherein
A burner, wherein a heat radiating member is provided on an outer peripheral surface of a cylindrical member that partitions the preheating chamber and the combustion chamber. The burner according to claim 1, wherein
A burner comprising a water supply device for supplying mist water to a combustion chamber of a lowermost combustion section. In the burner according to claim 3,
The fuel supply includes a screw conveyor,
The screw conveyor is provided with a backflow prevention unit for preventing a backflow of fuel to be conveyed. Burner according to claim 10,
The burner characterized in that the backflow prevention part is formed including a missing part of a screw blade. In the burner according to claim 3,
The burner is configured to supply auxiliary combustion air. In the burner according to claim 3,
The burner has a water supply unit for supplying water to the fuel as the combustion temperature rises abnormally. The burner according to claim 1, wherein
The burner characterized in that the fuel contains at least one of wood pellets, wood waste, plastic waste, rubber waste, RPF and PCB waste liquid.

Images