JP5694700B2 - Fluidized bed furnace and waste treatment method - Google Patents

Description

  The present invention relates to a fluidized bed furnace for extracting a combustible gas from the waste by heating the waste in a fluidized bed in which fluidized particles are fluidized, and a waste treatment method.

  Conventionally, the thing of patent document 1 is known as a fluidized bed furnace. As shown in FIG. 9, the fluidized bed furnace has a furnace body 104 having fluidized sand (fluidized particles) 102 at the bottom of the furnace and fluidization of the fluidized sand 102 to form a fluidized bed. And an air supply unit 106 for supplying air into the sand 102. The furnace main body 104 has a side wall, and an input unit 108 for supplying waste on the fluidized bed is provided on the side wall.

  In the fluidized bed furnace 100, the air supply unit 106 supplies air into the high temperature fluidized sand 102 to fluidize the fluidized sand 102 in a suspended state, thereby forming a fluidized bed. The air supply unit 106 is configured so that the fluidized state of the fluidized sand 102 is substantially constant throughout the fluidized bed so that the waste introduced into the fluidized bed from the input unit 108 can be taken into the bed and burned efficiently. Supply air.

  Each time waste is thrown into the high-temperature fluidized sand from the charging unit 108, the waste is mixed with the high-temperature fluidized sand 102 in the fluidized bed and thermally decomposed (gasified). Thereby, combustible gas is generated. This combustible gas is burned at a high temperature in a subsequent melting furnace, for example.

JP 2006-242454 A

  The waste thrown into the fluidized bed furnace 100 is taken into an active fluidized bed and burned or gasified, but the combustible in the waste burns rapidly each time the waste is thrown intermittently. As a result, rapid fluctuations in the amount and concentration of the generated combustible gas are repeated. Since this gasification reaction greatly depends on the quantitativeness of the waste supply, if there is a change in the waste supply or a change in the waste quality, the combustible gas cannot be generated stably. In particular, when the waste contains a large amount of flammable garbage such as paper or sheet-like plastic, the generated flammable gas fluctuates more and its stabilization is required.

  For example, when power generation is performed using the generated combustible gas in a gas engine, stable energy cannot be obtained if the fluctuation of the combustible gas is large. Is required more.

  Accordingly, it is an object of the present invention to provide a fluidized bed furnace and a waste treatment method that can stably obtain a combustible gas even if the waste contains easily burnable garbage.

  Therefore, in order to solve the above problems, the present invention is a fluidized bed furnace that heats waste and takes out combustible gas from the waste, and includes fluidized particles that constitute a fluidized bed for heating waste. A bottom wall that supports the fluidized particles from below and a side wall that rises from the bottom wall, the non-combustible material in the waste and the waste in the waste A mixture discharge port is provided for discharging carbide generated by heating together with the fluidized particles, and the upper surface of the bottom wall is disposed on the top surface of the bottom wall so as to lower the fluidized particles toward the mixture discharge port. A furnace body inclined to become lower toward the mixture discharge port, a gas supply section for fluidizing the fluidized particles by blowing fluidized gas from the bottom wall of the furnace body toward the fluidized particles, and the side The waste is supplied to a region adjacent to the supply side wall on the fluidized bed from a supply side wall located on the same side as the mixture discharge port with respect to the center position of the bottom wall. A waste supply unit that moves waste on the layer to the side of the side wall opposite to the mixture discharge port across the center position of the bottom wall of the side wall. The gas supply section has a first fluidization region having a fluidization degree such that waste can be retained on the upper side of the fluidized particles by blowing the fluidizing gas from the periphery of the mixture discharge port. And the fluidized gas is blown between the first fluidized region and the opposite side wall at a flow rate higher than the fluidized gas blown velocity in the first fluidized region. The fluidized particles have a higher degree of fluidization than the one fluidized region, thereby forming a second fluidized region in which the fluidized particles are convected and mixed with the waste to gasify the waste, The waste supply unit has the waste from the supply side wall so that the waste stays on the first flow region and the stayed waste sequentially enters the second flow region. Waste for fluidized bed And performing the supply of goods.

  According to this fluidized bed furnace, the first region around the mixture outlet and the second fluidized region having a higher degree of fluidization than the first region are formed in the fluidized bed, while the waste is The waste supply part is adjacent to the supply side wall on the fluidized bed so that the waste stays on the first fluidized region and the waste retained on the first fluidized region is sequentially sent to the second fluidized region side. By supplying waste to the area where it is discharged, the waste is sufficiently gasified while suppressing rapid fluctuations in the combustible gas recovered from the fluidized bed furnace, thereby stabilizing the combustible gas from the waste. Can be generated.

  Specifically, in the first flow region, the flow is suppressed so that the waste can be retained on the upper surface thereof, so that the waste is retained on the first flow region without being mixed with the flow particles. The flammable garbage in the waste gasifies slowly. Therefore, in the first flow region, rapid combustion of waste is suppressed, and thereby generation of combustible gas due to rapid gasification of waste is also suppressed. The waste staying on the first fluidized area sequentially enters the second area by supplying new waste into the furnace body by the waste supply section. Then, in this second flow region, since the flow is active and the temperature is high due to the combustion of the waste, the waste that has entered from the first flow region is sufficiently mixed with the flow particles, and thus the waste is disposed of. Goods are fully gasified and combustible gas is generated. As a result, intermittent and rapid generation of combustible gas can be suppressed, and generation of the gas can be stabilized.

  Further, by forming a first flow region above the mixture discharge port and supplying waste on the upper side, the flammable garbage in the waste is slowly gasified by staying on the first flow region. Even if incombustibles in the waste and carbides generated by heating the waste sink to the bottom of the furnace, they can be easily discharged from the furnace body. In addition, even if incombustibles and carbides sink to the bottom wall after the waste enters the second flow region from the first flow region, along the top surface of the bottom wall inclined so as to become lower toward the mixture discharge port. Incombustible materials and carbides fall, so these incombustible materials and carbides can be easily discharged.

  In addition, since the upper surface of the bottom wall is inclined so as to be lowered toward the mixture discharge port (that is, inclined so as to be lowered from the second region toward the first region), The hot fluid particles fall on the upper surface of the bottom wall toward the first fluid region, and thereby heat can be supplied to the first fluid region.

  The waste supply unit pushes a new waste laterally from the supply side wall toward the waste staying on the first flow region, and thereby the waste staying on the first flow region. It is preferable to sequentially move objects into the second flow region.

  According to this configuration, since the new waste is pushed sideways toward the waste that stays on the first fluidized area, the waste that is pushed by the waste and stays on the first fluidized area is reduced. It is possible to reliably enter the second flow region.

  The fluidized bed furnace includes a carbide insertion device that separates the carbide from the mixture of the incombustible material, the carbide, and the fluidized particles discharged from the mixture discharge port and returns the mixture to the fluidized bed from the opposite side wall side. Are preferred.

  According to such a configuration, the carbide insertion device obtains combustible gas from the carbide by returning the carbide discharged together with the flowing particles and the incombustible material from the mixture discharge port to the second flow region where the flow is active and high temperature. be able to. As a result, combustible gas can be efficiently obtained from the waste. Moreover, the temperature of the second fluidized region can be maintained at a high temperature by heat generated when the carbide is gasified.

In the fluidized bed furnace according to the present invention, U _mf is the minimum fluidization velocity that is the minimum flow velocity of the fluidizing gas for fluidizing the fluidized particles, and U ₀ is the average cross-sectional velocity of the fluidizing gas. Then, the air supply unit blows the fluidizing gas at a flow rate such that U ₀ / U _mf is 1 or more and less than 2 in the first flow region, and U ₀ / U in the second flow region. It is preferable to blow the fluidizing gas at a flow rate at which _mf is 2 or more and less than 5. A preferable first flow region and second flow region can be formed by blowing the fluidizing gas at such a flow rate. As a result, the waste can be suitably gasified while suppressing rapid combustion of the waste, and the combustible gas can be stably obtained from the waste.

  It is preferable to provide a sand circulation device that separates the flowing particles from the mixture discharged from the mixture discharge port and returns the separated flowing particles into the furnace body.

  In this way, the sand circulating device separates the high temperature fluidized particles from the mixture discharged from the mixture outlet and returns them to the furnace body, thereby maintaining the amount of fluidized particles constituting the fluidized bed and the fluidized bed. It becomes easy to maintain temperature.

  In this case, it is more preferable that the sand circulation device returns the fluidized particles separated from the mixture onto the waste that stays on the first fluidized region.

  In this way, the sand circulating device returns the hot fluid particles discharged from the mixture outlet onto the waste staying on the first fluid region, so that the hot fluid particles are used as an ignition source in the waste. It is possible to stably burn (gasify) flammable garbage.

  It is preferable that the furnace body has a planar shape in which the dimension in the width direction, which is a direction orthogonal to the pushing direction of the waste by the waste supply unit, is uniform in the pushing direction.

  According to this configuration, when the waste on the first flow region is pushed by the waste newly supplied from the waste supply unit and enters the second flow region, this moving direction of the furnace body Since the dimension in the width direction perpendicular to the direction is uniform, the movement of the waste is stabilized.

  The waste supply unit includes a pusher having a pushing surface extending in the width direction, and the pusher pushes the pusher so that the pushing surface of the pusher simultaneously pushes waste onto the fluidized bed over the entire width direction of the pushing surface. It is preferable to have a drive unit that reciprocates in a direction parallel to the direction.

  According to such a configuration, since the waste can be uniformly pushed in the width direction, the movement of the waste from the first flow region to the second flow region side becomes substantially uniform in the width direction, and the one in the furnace It is possible to prevent the waste from concentrating on the part.

  Further, in order to solve the above-mentioned problems, the present invention is a waste treatment method for heating waste and taking out combustible gas from the waste, and comprises a fluidized bed for heating the waste. And a bottom wall that supports the fluid particles from below and a side wall that rises from the bottom wall. A mixture discharge port for discharging carbide generated by heating the waste together with the fluidized particles is provided, and the fluidized particles descend on the upper surface of the bottom wall toward the mixture discharge port. A fluidized bed furnace having a furnace body inclined so that an upper surface of the furnace body is lowered toward the mixture outlet, and the fluidized particles from a region around the mixture outlet of the bottom wall of the furnace body Towards A first flow region having a fluidization degree that allows waste to stay on the upper side of the fluidized particles is formed by blowing the mobilized gas, and the first fluid region and the side wall are formed. The fluidizing gas is flown at a flow rate higher than the flow velocity of blowing the fluidizing gas in the first flow region between the mixture discharge port and the opposite side wall on the opposite side across the center position of the bottom wall. Forming a second fluidized region having a higher degree of fluidization of the fluidized particles than the first fluidized region by blowing, and the mixture discharge port with respect to a center position of the bottom wall of the side wall; Supplying the waste from a supply side wall located on the same side to a region adjacent to the supply side wall on the fluidized bed, thereby retaining the waste on the first fluidized region; and The accumulated waste The by sequentially entering the second flow area, characterized in that it comprises the steps of gasification, a.

  According to this waste treatment method, the first region around the mixture discharge port and the second fluid region having a higher degree of fluidization than the first region are formed in the fluidized bed, Stays on the first fluidized zone, and the waste that stays on the first fluidized zone enters the second fluidized region in order, so that the flammable gas recovered from the fluidized bed furnace is rapidly increased. This makes it possible to sufficiently gasify the waste while suppressing such fluctuations, thereby stably generating flammable gas from the waste.

  Further, by forming a first flow region above the mixture discharge port and supplying waste on the upper surface thereof, the flammable garbage in the waste is slowly gasified by staying on the first flow region. In the meantime, even if incombustibles in the waste and carbides generated by heating the waste sink to the furnace bottom, they can be easily and reliably discharged from the furnace body. In addition, even if incombustibles and carbides sink to the bottom wall after the waste enters the second flow region from the first flow region, along the top surface of the bottom wall inclined so as to become lower toward the mixture discharge port. Incombustible materials and carbides fall, so these incombustible materials and carbides can be easily discharged.

  In addition, since the upper surface of the bottom wall is inclined so as to be lowered toward the mixture discharge port (that is, inclined so as to be lowered from the second region toward the first region), The hot fluid particles fall on the upper surface of the bottom wall toward the first fluid region, and thereby heat can be supplied to the first fluid region.

  In the gasification step, new waste is pushed laterally from the supply side wall toward the waste staying on the first flow region, and thereby the waste staying on the first flow region. It is preferable to sequentially gasify the object by entering the second flow region.

  According to this configuration, since the new waste is pushed sideways toward the waste that stays on the first fluidized area, the waste that is pushed by the waste and stays on the first fluidized area is reduced. The gas can be reliably gasified by entering the second flow region.

  The waste treatment method includes a step of separating the carbide from the mixture of the incombustible material, the carbide, and the fluidized particles discharged from the mixture discharge port and returning the separated carbide to the fluidized bed from the opposite side wall side. Are preferred.

  According to such a configuration, the carbide discharged together with the flowing particles and the incombustible material from the mixture discharge port is separated and returned to the second flow region where the flow is active and high temperature, thereby reliably gasifying the carbide. Can do. Moreover, it becomes easy to maintain the temperature of the second fluidized region at a high temperature by heat generated when the carbide is gasified.

In this waste treatment method, if the minimum fluidization speed, which is the minimum flow velocity of the fluidizing gas for fluidizing the fluidized particles, is U _mf and the average cross-sectional flow velocity of the fluidizing gas is U _0. In the first flow region, the fluidizing gas is blown at a flow rate at which U ₀ / U _mf is 1 or more and less than 2, and in the second flow region, a flow rate at which U ₀ / U _mf is 2 or more and less than 5. It is preferable that the fluidizing gas is blown. A preferable first flow region and second flow region can be formed by blowing the fluidizing gas at such a flow rate. As a result, the waste can be suitably gasified while suppressing rapid combustion of the waste, and the combustible gas can be stably obtained from the waste.

  As described above, according to the present invention, it is possible to provide a fluidized bed furnace and a waste treatment method capable of stably obtaining a combustible gas even if the waste contains easily burnable garbage.

It is a schematic structure figure of a fluidized bed furnace concerning this embodiment. It is a cross-sectional view of the furnace main body for demonstrating the insertion position of the waste in the said fluidized bed furnace, the insertion position of a fluid particle, and the insertion position of a carbide | carbonized_material. It is a figure for demonstrating arrangement | positioning of the nozzle in the bottom wall of the said furnace main body. It is a figure for demonstrating the furnace main body which has a reflection part in the front wall in the fluidized-bed furnace which concerns on other embodiment. It is a figure for demonstrating the furnace main body which has a guide part in the rear wall in the fluidized-bed furnace which concerns on other embodiment. It is a figure for demonstrating the furnace main body which has a roof part in the front wall and rear wall in the fluidized-bed furnace which concerns on other embodiment. It is a figure for demonstrating the furnace main body provided with the thermometer and air supply part in the fluidized-bed furnace which concerns on other embodiment. It is a figure for demonstrating the waste supply part in the fluidized-bed furnace which concerns on other embodiment. It is a schematic block diagram of the conventional fluidized bed furnace.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  The fluidized bed furnace according to the present embodiment is a furnace that extracts combustible gas from waste by heating the waste with high-temperature fluidized particles. As shown in FIG. 1, the fluidized bed furnace includes fluidized particles 12, a furnace body 20, a gas supply unit 30, a waste supply unit 40, a sand circulation device 50, and a carbide insertion device 60. Prepare.

  The fluidized particles 12 constitute the fluidized bed 14 inside the furnace body 20 and are particles for heating the waste 18. That is, the fluidized particles 12 heated to a high temperature by the combustion of a part of the waste 18 are mixed with the waste 18, whereby the waste 18 is gasified and combustible gas is generated. In the present embodiment, silica sand or the like is used as the fluidized particles 12.

  The furnace body 20 is a part that has the fluidized particles 12 inside and takes out the combustible gas from the waste 18 by the hot fluidized particles 12. The furnace body 20 includes a bottom wall 21 that supports the fluidized particles 12 from below, a side wall 22 that rises from the bottom wall 21, and a combustible gas discharge part 23 that is provided at the upper end of the side wall 22.

  The side wall 22 has a rectangular tube shape extending vertically. Specifically, as shown in FIG. 2, the side wall 22 includes a front wall (supply side wall) 24 and a rear wall (opposite side wall) 25 that are opposed to each other at the front and rear (left and right in FIG. 2). The front walls 24 and the rear walls 25 have lateral walls 26 and 26 that connect the ends of the front walls 24 and 25, respectively. The lateral walls 26, 26 are parallel to each other. That is, the furnace body 20 has a planar shape in which the dimension in the width direction, which is the distance between the lateral walls 26, 26, is uniform in the front-rear direction.

  A sand insertion portion 27 for inserting the fluidized particles 12 into the furnace body 20 is inserted into the side wall (front wall) 24 located on the same side as the mixture discharge port 29 with respect to the center position of the bottom wall 21. And a waste insertion port 28 for inserting the waste 18 into the furnace body 20 is provided. Further, a side wall (rear wall) 25 located on the side opposite to the mixture discharge port 29 across the center position of the bottom wall 21 of the side wall 22 is made of carbide (for example, char) generated by heating the waste 18. A carbide insert 63 for insertion is provided.

  The sand insertion part 27 is provided in the center part in the width direction at the lower part of the front wall 24 so that fluid particles can be inserted into the center part in the width direction on the front wall 24 side in the furnace body 20 (see FIG. 2). The sand insertion portion 27 is provided from the upper side of the fluidized particles 12 (fluidized bed 14) supported by the bottom wall 21 of the furnace body 20 to the fluidized bed 14 (specifically, the waste 18 that is supplied and retained on the fluidized bed 14). ) Is provided at a height where the flowing particles 12 can be introduced. By providing the sand insertion portion 27 at such a position, the fluidized particles 12 can be introduced onto the waste 18 that stays on the fluidized bed 14, thereby using the fluidized particles 12 as an ignition source. Only the easily burnable garbage in the waste 18 can be stably burned (gasified) first. The place where the flowing particles 12 are introduced is not limited to the front wall 24 but may be provided on the rear wall 25 or the lateral wall 26.

  The carbide insertion part 63 is provided in the center part in the width direction at the lower part of the rear wall 25 so that the carbide can be inserted into the center part in the width direction on the rear wall 25 side in the furnace body 20 (see FIG. 2). The carbide insertion portion 63 is provided at a height position at which carbide can be introduced from above the fluidized bed 14 in the furnace body 20 toward the fluidized bed 14. In addition, the carbide | carbonized_material insertion part 63 may be provided in the intermediate | middle height position of the fluidized bed 14 in an up-down direction. If it is provided at such a position, the carbide can be directly inserted into the fluidized bed 14, so that when it is introduced from the upper part of the fluidized bed 14, it stays on the fluidized bed 14 and is not easily mixed with the fluidized particles 12. Even so, it can be reliably inserted into the fluidized bed 14 and gasified.

  The waste insertion port 28 is provided in substantially the entire width direction in the lower part of the front wall 24. The waste insertion port 28 is at a height position where the waste 18 can be pushed sideways onto the upper surface of the fluidized particles 12 (fluidized bed 14) supported by the bottom wall 21 of the furnace body 20, that is, the fluidized bed 14. The lower end of the waste insertion port 28 is provided at a position slightly higher than the upper surface.

  The combustible gas discharge part 23 is a part for discharging the combustible gas generated in the furnace body 20. The combustible gas discharge part 23 has an outer diameter smaller than that of the side wall 22 so that a duct or the like for supplying the combustible gas obtained in the furnace body 20 to a gas engine or the like of a subsequent power generation process can be connected. ing.

  The bottom wall 21 is provided with a mixture outlet 29 for discharging incombustibles in the waste 18 and carbides generated by heating the waste 18 together with the fluidized particles 12 at a position deviated in a specific direction from the center position. It is done. The mixture discharge port 29 is open in the entire width direction in the bottom wall 21. The upper surface 21a of the bottom wall 21 is inclined so as to become lower toward the mixture outlet 29 so that the fluidized particles 12 descend on the upper surface 21a. In the bottom wall 21 of the present embodiment, a mixture discharge port 29 is provided at a position biased to the front side, and the upper surface 21a of the bottom wall 21 moves downward (from left to right in FIG. 1) at a certain level. It is an inclined surface that forms a gradient. Specifically, the upper surface 21a of the bottom wall 21 is an inclined surface of 15 ° to 25 ° with respect to the horizontal plane. By providing the mixture discharge port 29 at such a position, the mixture settles from the waste 18 inserted in the region adjacent to the front wall 24 on the fluidized bed 14 from the waste insertion port 28 provided in the front wall 24. Incombustibles and carbides can be efficiently discharged out of the furnace body 20. Incombustible materials and carbides that settle in the fluidized bed 14 from the waste 18 diffused to the rear wall 24 side on the fluidized bed 14 also descend to the mixture outlet 29 along the inclination of the upper surface 21a of the bottom wall 21. These incombustibles and carbides can also be easily discharged out of the furnace body 20.

  Further, by inclining the upper surface 21a of the bottom wall 21 so as to become lower toward the mixture discharge port 29, in the operation of the fluidized bed furnace 10, the region adjacent to the upper surface 21a of the fluidized bed 14 is separated from the rear wall 25. The fluidized particles 12 move toward the front wall 24.

  The gas supply unit 30 fluidizes the fluidized particles 12 by blowing fluidized gas from the bottom wall 21 toward the fluidized particles 12. The gas supply unit 30 includes a plurality of nozzles 31 for blowing out the fluidizing gas, a wind box 32 that supplies the fluidizing gas to each nozzle 31, a blower unit 33 that blows the fluidizing gas to the wind box 32, Have

  The plurality of nozzles 31 are arranged on the bottom wall 21 in a lattice shape spaced in the width direction and the front-rear direction. Each nozzle 31 is attached to the bottom wall 21 so as to penetrate the bottom wall 21. In this embodiment, as shown in FIG. 3, the bottom wall 21 is divided into a rear region 21b and a front region 21c, and the number of nozzles 31 provided in the rear region 21b is provided in the front region 21c. The nozzles 31 are disposed in the regions 21b and 21c so as to be larger than the number of nozzles 31 formed. The number of nozzles 31 between the regions 21b and 21c is not limited, and the number of nozzles 31 in the front region 21c and the number of nozzles 31 in the rear region 21b may be the same. Further, the number of nozzles 31 in the front region 21c may be larger than the number of nozzles 31 in the rear region 21b.

  The air box 32 has a box shape extending in the width direction, serves as a header for distributing the fluidized gas to the nozzles 31 arranged in the width direction on the bottom wall 21, and is blown out from the nozzles 31 arranged in the width direction. It has a function to make the flow rate of fluidized gas uniform. In the present embodiment, a plurality of wind boxes 32 are arranged in the front-rear direction on the lower surface side of the bottom wall 21. Therefore, it is possible to change the flow rate of the fluidizing gas blown from the nozzle 31 for each nozzle 31 corresponding to each wind box 32. In the present embodiment, five wind boxes 32a, 32b, 32c, 32d, and 32e are arranged in the front-rear direction. Specifically, four wind boxes 32a, 32b, 32c, and 32d are arranged on the rear wall 25 side of the mixture discharge port 29, and one wind box 32e is arranged on the front wall 24 side of the mixture discharge port 29. ing.

  The air blowing unit 33 is a part for blowing (supplying) the fluidizing gas to each wind box 32 and can blow the fluidizing gas at a different flow rate for each wind box 32. The air blowing unit 33 of the present embodiment is configured so that the flow rate of the fluidized gas blown to the wind box 32 on the rear side of the flow rate of the fluidized gas blown to the wind box 32 on the front side with respect to the wind boxes 32 and 32 adjacent in the front-rear direction. The fluidizing gas is blown so that the flow rate is increased. The air blowing unit 33 blows air as a fluidizing gas to each wind box 32, but in addition to this air, an inert gas such as nitrogen can also be blown.

  Specifically, during normal operation of the fluidized bed furnace 10, that is, when the waste 18 is inserted into the furnace body 20 and flammable gas is generated from the waste 18, the blower 33 is connected to the mixture outlet 29. A fluidizing gas is blown from the periphery of the fluid to form a first fluidized region 15 having a fluidization degree that allows the waste 18 to stay on the upper side of the fluidized particles 12, and the first fluidized region. The fluidized gas is blown between the first fluidized region 15 and the rear wall 25 at a flow rate higher than the fluidized gas blown velocity in the first fluidized region 15, so A second flow region 16 having a high degree of fluidization is formed. That is, as described above, the air blowing unit 33 has a wind box (for example, rear side of the flow rate of the fluidized gas blown to the front side air box (for example, 32c) with respect to the wind box 32 adjacent in the front-rear direction. By increasing the flow rate of the fluidizing gas blown to 32b), the fluidized bed 14 forms the first fluidized region 15 in which the fluidized state is suppressed around the mixture discharge port 29, and the first fluidized region 15 And the rear wall 25, a second flow region 16 in which flow is active is formed. Further, the air blowing unit 33 makes the flow rate of the fluidizing gas supplied to the wind boxes 32c, 32d, 32e on the front wall 24 side constant, and fluidizes the flow rate supplied to the wind boxes 32a, 32b on the rear wall 25 side from this flow rate. By increasing the gas flow rate, the first fluidized region 15 in which the flow is suppressed is formed in the region corresponding to the wind boxes 32c, 32d, and 32e on the front wall 24 side in the fluidized bed 14, and the rear wall 25 side is formed. You may form the 2nd flow area | region 16 where a flow is active in the area | region corresponding to the wind boxes 32a and 32b.

Specifically, in the first flow region 15, the blower unit 33 blows the fluidizing gas at a flow rate at which U _o / U _mf is 1 or more and less than 2, and in the second flow region 16, U _o / U Fluidizing gas is blown at a flow rate at which _mf is 2 or more and less than 5. Here, U _mf is the minimum fluidizing velocity is the minimum flow rate of the blowing of the fluidizing gas for fluidizing the fluidized particles 12, U _o is the average cross-sectional velocity of the fluidizing gas.

  On the other hand, when the fluidized bed furnace 10 is stopped, that is, when the insertion of the waste 18 into the furnace body 20 is stopped, the blower unit 33 supplies an inert gas to the air as a fluidizing gas supplied to each wind box 32. Blow the mixture. And the ventilation part 33 suppresses that the waste 18 which remains in the furnace main body 20 burns violently by making the ratio of the air and inert gas in fluidization gas gradually increase the inert gas, The temperature rise in the furnace body 20 is suppressed.

  Specifically, in the furnace body 20, during normal operation, the waste 18 is burned and gasified in a state where the oxygen concentration is lower than a value suitable for the combustion of the waste 18. When the insertion of the waste 18 into the furnace main body 20 is stopped in this state, the amount of combustible material in the furnace main body 20 decreases, but a predetermined amount is maintained in the furnace main body 20 in order to maintain the fluidized bed 14. Since fluidized gas (air) is supplied at a flow rate, the oxygen concentration in the furnace body 20 is increased. When the oxygen concentration in the furnace body 20 becomes a value suitable for the combustion of the waste 18 remaining in the furnace body 20, the waste 18 burns violently and the temperature in the furnace body 20 is higher than that during normal operation. To rise. When the inside of the furnace body 20 reaches such a high temperature state, the fluidized particles 12 forming the fluidized bed 14 are hardened by this heat. When the fluidized particles 12 are thus solidified, the fluidized particles 12 are not fluidized even if the fluidized gas is blown into the fluidized particles 12 to form the fluidized bed 14 next time. Therefore, when the insertion of the waste 18 into the furnace body 20 is stopped, the blower unit 33 mixes an inert gas with the air blown into the furnace body 20 and gradually increases the ratio of the inert gas. Thereby, the oxygen concentration in the furnace main body 20 is kept lower than a value suitable for the combustion of the waste 18, and as a result, the waste 18 remaining in the furnace main body 20 is suppressed from burning violently.

  Further, the blower 33 can adjust the temperature of the fluidizing gas blown to the wind box 32. When the operation of the fluidized bed furnace 10 is started, the blower unit 33 blows a high-temperature fluidized gas from the portion corresponding to the second fluidized region 16 toward the fluidized particles 12 to combust the waste 18 or gas. The fluidized particles 12 are heated until reaching a temperature at which the temperature can be adjusted. In this case, when the fluidized particles 12 become high temperature and the combustion of the waste 18 starts, the temperature of the fluidized particles 12 is maintained by this combustion, and therefore the blower 33 lowers the temperature of the fluidized gas blown to the wind box 32. May be.

  The waste supply unit 40 is a part that supplies the waste 18 from the front wall 24 to a region adjacent to the front wall 24 on the fluidized bed 14. The waste supply unit 40 of the present embodiment pushes the waste 18 sideways onto the fluidized bed 14 from the front wall 24 (specifically, the waste insertion port 28 of the front wall 24). It is a site | part moved to the 2nd flow area | region 16 side. That is, the waste supply unit 40 has the waste 18 so that the waste 18 stays on the first flow region 15 and the stayed waste 18 sequentially enters the second flow region 16. Push in. The waste supply unit 40 includes a pusher 41 and a drive unit (not shown) for driving the pusher 41. The pusher 41 has a pushing surface 42 extending in the width direction. In this embodiment, the length in the width direction of the pushing surface 42 is the same as the width of the waste insertion port 28 of the front wall 24, and the length in the vertical direction is approximately half of the opening height of the waste insertion port 28. is there. The pusher 41 is installed to be movable in the front-rear direction at the same height as the waste insertion port 28. The drive unit includes a power source such as a motor and a cylinder, and the pusher 41 is reciprocated in the front-rear direction by the power. The specific configuration of the waste supply unit 40 is not limited. For example, in the waste supply unit 40 of the present embodiment, the pusher 41 pushes the waste 18 into the furnace, but the waste 18 may be pushed into the furnace by a screw pusher or the like (see FIG. 8A). ). By using the pusher 41 and the screw pusher, it is possible to supply litter that is small in bulk specific gravity such as paper or plastic sheet and easily scatters into the furnace body 20 in a lump. Compared with the case where it throws in, it can suppress that these refuse scatter in the furnace main body 20. FIG.

  The sand circulation device 50 is a device that circulates the fluidized particles 12 by separating the fluidized particles 12 from the mixture of incombustibles, carbides, and fluidized particles 12 discharged from the mixture outlet 29 and returning them to the furnace body 20. is there. In this manner, the sand circulating device 50 separates the high temperature fluidized particles 12 from the mixture and returns them to the furnace body 20, thereby maintaining the amount of fluidized particles 12 constituting the fluidized bed 14 in the furnace body 20. It becomes easy to maintain the temperature of the fluidized bed 14. The sand circulation device 50 includes a mixture discharge unit 51, a fluid particle separation unit 52, and a fluid particle transport unit 53.

  The mixture discharge unit 51 is provided below the mixture discharge port 29 on the bottom wall 21, and moves the mixture of the noncombustible material, the carbide, and the fluidized particles 12 that have dropped from the mixture discharge port 29 to the fluidized particle separation unit 52. The mixture discharge part 51 of this embodiment moves the mixture which has fallen from the mixture discharge port 29 to the fluid particle separation part 52 with a screw pushing machine. The fluid particle separation unit 52 separates the fluid particles 12 from the mixture sent from the mixture discharge unit 51. The fluid particle separator 52 of the present embodiment separates the fluid particles 12 from the mixture by sieving. The fluidized particle separation unit 52 sends the mixture after separating the fluidized particles 12 to the carbide separation unit 61. The fluidized particle transport unit 53 transports the fluidized particles 12 separated in the fluidized particle separation unit 52 to the sand insertion unit 27 of the furnace body 20 and inserts the fluidized particle 12 into the furnace body 20 from the sand insertion unit 27.

  In addition, although the sand circulating apparatus 50 of this embodiment has thrown the fluidized particle 12 toward the upper surface of the said fluidized bed 14 from the upper direction of the fluidized bed 14, it is not limited to this, It pushes directly in the fluidized bed 14 In this manner, the fluidized particles 12 may be returned to the fluidized bed 14.

  The carbide insertion device 60 is a device that separates the carbide from the mixture discharged from the mixture discharge port 29 and returns it to the furnace body 20 from the rear wall 25 side. In this way, by returning the carbide discharged from the mixture discharge port 29 to the second flow region 16, it becomes possible to obtain a combustible gas from the carbide discharged together with the incombustible material outside the furnace body 20. As a result, combustible gas can be efficiently obtained from the waste 18 supplied to the fluidized bed furnace 10. Moreover, the temperature of the 2nd flow area | region 16 can be maintained at the high temperature with the heat | fever when gasifying a carbide | carbonized_material. The carbide insertion device 60 includes a carbide separation unit 61 and a carbide conveyance unit 62.

  The carbide separation unit 61 separates carbides from the mixture sent from the fluidized particle separation unit 52. The carbide separation unit 61 of the present embodiment separates carbides from the mixture after the fluidized particles 12 are separated in the fluidized particle separation unit 52. As the carbide separation unit 61, for example, a specific gravity separator that separates carbides from the mixture by vibration is used. The carbide transport unit 62 transports the carbide separated in the carbide separation unit 61 to the carbide insertion unit 63 of the furnace body 20 and inserts the carbide into the furnace body 20 from the carbide insertion unit 63.

  In the fluidized bed furnace 10 configured as described above, the combustible gas is recovered from the waste 18 as follows.

  The air blowing unit 33 supplies the fluidizing gas to each wind box 32. As a result, fluidized gas is blown from the bottom wall 21 toward the fluidized particles 12, and the fluidized bed 14 is formed in the furnace body 20. At this time, the air blowing unit 33 adjusts the flow rate of the fluidizing gas blown to each wind box 32 to form the first fluidized region 15 in which the flow is suppressed on the mixture outlet 29 side in the fluidized bed 14. A second flow region 16 in which flow is active is formed between the first flow region 15 and the rear wall 25. Further, the blower unit 33 supplies the high-temperature fluidized gas to the wind box 32 (in the present embodiment, for example, the wind boxes 32a and 32b in the present embodiment) corresponding to the second flow area 16, thereby providing the second flow area. Sixteen fluidized particles 12 are actively heated. At this time, heat is transferred to the first fluidized region 15 by the movement of the fluidized particles 12 from the second region 16 near the upper surface 21a of the fluidized bed 14 to the first region 15 caused by the inclination of the upper surface 21a of the bottom wall 21. Can be supplied.

  In this way, the temperature of each region 15, 16 of the fluidized bed 14 formed in the furnace body 20 is a predetermined temperature (in this embodiment, the temperature of the second fluidized region 16 is about 600 ° C. to 800 ° C., When the temperature of the first flow region 15 reaches approximately 400 ° C. to 600 ° C., the waste supply unit 40 starts to push the waste 18 into the furnace body 20 from the waste insertion port 28. Specifically, the pusher 41 driven by the driving unit pushes the waste 18 sideways toward the rear wall 25 side. Thereby, the waste 18 is pushed into the area adjacent to the front wall 24 on the first flow area 15 (see FIG. 2).

  Since the flow of the fluidized particles 12 is suppressed in the first fluidized region 15, the pushed waste 18 is not actively mixed with the fluidized particles 12, and most of the waste is on the first fluidized region 15. And some of the heavy incombustibles and carbides settle. As the waste 18 stays in this way, in the first flow region 15, the rapid combustion of the waste 18 is suppressed, and the gas that is easily gasified in the waste 18 by the heat radiation in the furnace body 20 is gas. It becomes. That is, the waste 18 that is easily gasified, such as plastic and paper, is gasified while moving on the surface layer of the first flow region 15. On the other hand, some of the wood pieces and the like which are difficult to gasify are partially gasified, but most of them reach the second flow region 16 without being gasified. Before the waste 18 that is easily gasified reaches the intense fluidized bed (second fluidized region 16), the waste 18 that is easily gasified is gasified in the first fluidized region 15 under mild conditions. The fluctuation of combustible gas is suppressed. Further, since the heavy incombustible material settles in the first flow region 15 and is discharged as it is from the mixture discharge port 29, the incombustible material is unlikely to stay in the hearth. On the other hand, some wastes such as wood chips that are difficult to gasify may be discharged from the mixture discharge port 29 in a state of passing through the first flow region 15 and being carbonized. The staying waste 18 is combusted by the temperature in the furnace main body 20 (heat of the free board part) as described above, but the temperature in the furnace main body 20 is 800 to 900 ° C. and the fluidized bed 14 is formed. Although it is higher than the flowing particles 12, the contact with the air is not good, so that flammable garbage such as paper and sheet-like plastics mainly contained in the waste 18 is gasified. At this time, since the temperature is low and the air (fluidized gas) supplied to the first flow region 15 is small, even the flammable garbage is gradually gasified. Further, due to the flow of the fluidized particles 12 by the fluidizing gas, a part of the staying waste 18 moves little by little from the first fluidized region 15 to the second fluidized region 16 (from the right side to the left side in FIG. 1) or Spread. For this reason, even when the waste 18 is put in a lump and there is a flammable paper inside, the paper is gasified by coming out to the surface side of the lump at the time of diffusion. As described above, in the first flow region 15, the rapid combustion of the waste 18 is suppressed, and the rapid increase of the combustible gas when the waste 18 is inserted is prevented.

  Next, the new waste 18 is pushed into the furnace main body 20 from the waste insertion port 28 by the pusher 41. As a result, the waste 18 staying on the first flow region 15 is pushed by the pushed new waste 18 and sequentially enters the second region 16 side. In the second flow region 16, since the flow is active and the temperature of the waste 18 is increased due to the combustion of the waste 18, the waste 18 that has entered from the first flow region 15 is mixed with the fluidized particles 12 and is sufficiently gasified. As a result, combustible gas is generated. Specifically, in the fluidized bed 14, the fluidized state gradually becomes active from the front wall 24 toward the rear wall 25, so that the waste 18 is removed from a region adjacent to the front wall 24 on the first fluidized region 15. As it proceeds to the second fluidized region 16, it is gradually mixed with the fluidized particles 12. Further, as the flow proceeds from the first flow region 15 to the second flow region 16, the amount of air (fluidized gas) that is blown increases, so that the waste 18 burns and the temperature of the fluidized particles 12 increases. In the high-temperature second fluidized region 16, the waste 18 is sufficiently mixed with the fluidized particles 12, so that the waste 18 left unburned in the first fluidized region 15 in the second fluidized region 16. Gasification is sufficiently performed.

  On the other hand, the waste 18 newly pushed onto the first fluidized region 15 by the pusher 41 stays on the first fluidized region 15 with little mixing with the fluidized particles 12 as described above, and vigorously burns. It burns gradually in a restrained state.

  As described above, the waste 18 is pushed in one after another by the pusher 41 in a state where the first fluidized region 15 and the second fluidized region 16 are formed in the fluidized bed 14, so that the combustible gas is intermittently and suddenly pushed. Generation can be suppressed and generation of the gas can be stabilized.

  Incombustibles and carbides that have settled in the first fluidized region 15 are discharged together with the fluidized particles 12 from a mixture outlet 29 provided on the lower side of the first fluidized region 15. Moreover, since the upper surface 21a of the bottom wall 21 inclines with the downward slope toward the mixture discharge port 29, the incombustible material and carbide which settled in the 2nd flow area | region 16 descend | fall along this, and a mixture discharge port It moves to 29 and is discharged together with the fluidized particles 12. Then, the sand circulating device 50 separates the fluidized particles 12 from the mixture discharged from the mixture discharge port 29 and inserts it into the furnace body 20, and the carbide insertion device 60 is discharged from the mixture discharge port 29. The carbide is separated from the mixture and inserted into the furnace body 20. Specifically, the mixture discharge unit 51 sends the mixture dropped from the mixture discharge port 29 of the furnace body 20 to the fluidized particle separation unit 52, and the fluidized particles 12 separated from the mixture in the separation unit 52 are fed to the fluidized particle transport unit 53. Is conveyed to the sand insertion portion 27 of the furnace body 20. Thereby, the amount of the fluidized particles 12 forming the fluidized bed 14 is maintained in the furnace body 20. On the other hand, the fluidized particle separation unit 52 sends the mixture from which the fluidized particles 12 are separated to the carbide separation unit 61, and the carbide separation unit 61 separates the carbide from the mixture. And the carbide | carbonized_material which the carbide | carbonized_material conveyance part 62 isolate | separated is conveyed to the carbide | carbonized_material insertion part 63 of the furnace main body 20. FIG. Thereby, the carbide | carbonized_material discharged | emitted from the furnace main body 20 with the incombustible can be returned in the furnace main body 20, and can be gasified, As a result, combustible gas can be efficiently obtained from the waste 18 in the said fluidized bed furnace 10. Can do.

  When the fluidized bed furnace 10 is stopped, first, the pushing of the waste 18 into the furnace body 20 by the pusher 41 is stopped. When the pushing of the waste 18 is stopped, the blower unit 33 blows air in which an inert gas is mixed as a fluidizing gas supplied to each wind box 32. At this time, the air blowing unit 33 suppresses the oxygen concentration in the furnace body 20 by gradually increasing the ratio of the air to the inert gas in the fluidized gas and the inert gas as time passes, so that the fluidized bed It suppresses that the waste 18 which remains in 14 burns violently.

  In the present embodiment, when the fluidized bed furnace 10 is stopped, the combustion of the waste 18 remaining in the fluidized bed 14 is suppressed by increasing the ratio of the inert gas in the fluidized gas. The layer 14 may be sprayed with water to prevent the remaining waste 18 from burning.

  Thus, in the fluidized bed furnace 10, even if the waste contains a lot of flammable garbage, intermittent and rapid generation of the combustible gas can be suppressed and the generation of the gas can be stabilized. Specifically, in a state where the first region 15 around the mixture outlet 29 and the second fluidized region 16 having a higher degree of fluidization than the first region 15 are formed in the fluidized bed 14, The new waste 18 is pushed onto the first flow region 15, and the new waste 18 stays on the first flow region 15 and sequentially enters the second flow region 16 side. Is repeated. As a result, in the fluidized bed furnace 10, the waste 18 can be sufficiently gasified while suppressing rapid fluctuation of the obtained combustible gas, and the combustible gas can be stably generated from the waste 18. . In addition, since the waste 18 is not exposed to the active fluidized bed 14 (second fluidized region 16) immediately after being charged, a large amount of lightweight waste rises into the furnace body 20 and rapidly burns in the free board portion. Can be suppressed.

  Further, the first flow region 15 is formed above the mixture discharge port 29 and the waste 18 is supplied to the upper side of the first flow region 15, so that the first flow region 15 stays on the first flow region 15 and easily burns in the waste 18. Even if incombustibles and carbides sink to the furnace bottom while the gas is slowly gasified, these can be easily discharged from the furnace body 20. Moreover, even if incombustibles and carbides sink to the bottom wall 21 after the waste 18 enters the second flow region 16 from the first flow region 15, the waste 18 is inclined toward the mixture discharge port 29. Since incombustibles and carbides fall along the bottom wall upper surface 21a, these incombustibles and carbides can be easily discharged. Further, since the fluidizing gas is actively supplied in the second flow region 16, this also promotes the descent toward the mixture outlet 29 of incombustibles and carbides.

  Since the furnace body 20 has a uniform planar shape in the width direction in the pushing direction of the waste 18, the waste 18 on the first flow region 15 is newly pushed from the waste supply unit 40. When the waste 18 is pushed by the waste 18 and enters the second flow region 16, the movement of the waste 18 is stabilized.

  In the waste supply unit 40, the pusher 41 reciprocates in a direction parallel to the pushing direction (front-rear direction) so that the pushing surface 42 simultaneously pushes the waste 18 onto the fluidized bed 14 over the entire width direction of the pushing surface 42. This pushes the waste 18 uniformly in the width direction. Therefore, the movement of the waste 18 from the first flow region 15 to the second flow region 16 becomes substantially uniform in the width direction, and it is possible to prevent the waste 18 from concentrating on a part of the furnace.

  Note that the fluidized bed furnace and the waste treatment method of the present invention are not limited to the above-described embodiments, and it is needless to say that various modifications can be made without departing from the scope of the present invention.

  Although the side wall 22 of the said embodiment has stood up straight from the bottom wall 21 to the combustible gas discharge part 23, it is not limited to this. For example, as shown in FIG. 4, the front wall 24 </ b> A may include a reflecting portion 224 that extends toward the rear wall 25 so as to cover the upper part of the first flow region 15 at a predetermined height position. According to the front wall 24 </ b> A, the waste 18 staying on the first flow region 15 is heated by the radiant heat from the reflecting portion 224, and as a result, the waste 18 staying on the first flow region 15. From the above, combustible gas can be generated. That is, the gasification of the waste 18 staying on the first flow region 15 is promoted. In this case, the sand insertion portion 27 may be provided in a portion of the front wall 24A that stands vertically from the bottom wall 21 or may be provided in the reflection portion 224.

  Further, as shown in FIG. 5, the rear wall 25 </ b> A may include a guide portion 225 extending toward the front wall 24 so as to cover the second flow region 16 at a predetermined height position. The guide unit 225 guides the combustible gas so that the high-temperature combustible gas generated from the waste 18 in the second flow region 16 contacts the waste 18 staying on the first flow region 15, Thereby, the combustible gas contributes to the heating of the waste 18 on the first flow region 15. As a result, gasification of the waste 18 staying on the first flow region 15 is promoted without adding a special heating means. In this case, the carbide insertion portion 63 may be provided at a portion of the rear wall 25 that stands vertically from the bottom wall 21 or may be provided at the guide portion 225.

  Further, as shown in FIG. 6, the furnace body 20 may include roof portions 324 and 325 extending in a direction in which the front wall 24B and the rear wall 25B approach each other at the same height position. According to the front wall 24B and the rear wall 25B, the waste 18 staying on the first flow region 15 is heated by the radiant heat from the roof portion 324 of the front wall 24B, and gasification is promoted. Further, the furnace body 20B can be downsized by reducing the size in the front-rear direction of the furnace body 20B at a position lower than the combustible gas discharge part 23 at the upper end of the furnace body 20B. In this case, the sand insertion portion 27 may be provided in a portion of the front wall 24B that stands vertically from the bottom wall 21 or may be provided in the roof portion 324. The carbide insertion portion 63 may also be provided at a portion of the rear wall 25 </ b> B that is vertically rising from the bottom wall 21 or may be provided at the roof portion 325.

  In the above embodiment, only carbide is inserted from the carbide insert 63 into the furnace body 20, but may be inserted together with the fluidized particles 12.

  Moreover, although the carbide | carbonized_material insertion apparatus 60 of the said embodiment inserts the carbide | carbonized_material isolate | separated from the mixture into the furnace main body 20 as it is from the carbide | carbonized_material insertion part 63, you may insert into the furnace main body 20 after crushing the isolate | separated carbide | carbonized_material. . Thereby, even if the carbide | carbonized_material discharged | emitted from the mixture discharge port 29 is a big lump, it can be made into the predetermined magnitude | size which is easy to gasify by heating, and can be returned in the furnace main body 20. FIG.

  Further, the upper surface 21 a of the bottom wall 21 may be curved without being inclined straight from the rear wall 25 toward the mixture discharge port 29.

  As shown in FIG. 7, a plurality of thermometers T are disposed above the first flow region 15 and an air supply unit 65 capable of supplying air is provided on the first flow region 15. Good. According to such a configuration, it is possible to estimate the staying amount of the waste 18 staying on the first flow region 15 and control this staying amount. Specifically, the retention amount of the waste 18 on the first flow region 15 is estimated using the fact that the indicated value of the thermometer T buried in the waste 18 becomes low. When the amount of residence is large, that is, when the thermometer T buried in the waste 18 is large, air is supplied from the air supply unit 65 to raise the temperature in the furnace body 20. Then, gasification of the waste 18 staying on the first flow region 15 is promoted, and the staying amount of the waste 18 is reduced. As another method, if the temperature of the specified thermometer T is equal to or higher than the threshold value, it is determined that there is no dust at the position of the thermometer T. If the temperature is lower than the threshold value, the position of the thermometer T is dirty. The amount of air may be controlled by determining that it is buried in garbage.

  In the said embodiment, although the ventilation part 33 ventilates air and an inert gas as fluidization gas, according to the combustion state in the furnace main body 20, it is comprised so that water vapor | steam and oxygen may be ventilated as fluidization gas. Also good. Further, the fluidized bed furnace 10 is provided with a gas supply unit on the side wall 22 in addition to the gas supply unit 30, and air or gas is supplied from the gas supply unit into the furnace body 20 according to the combustion state of the fluidized bed 14 or the waste 18. You may be comprised so that oxygen, water vapor | steam, etc. can be supplied.

  Further, a high-temperature fluidizing gas may be supplied as the air (fluidizing gas) supplied to the first fluidizing region 15. By supplying a high-temperature fluidized gas, the amount of fluidized gas supplied is increased even when the first fluidized region 15 cannot be maintained at a necessary temperature only by heat transmitted from the second fluidized region 16. Without this, the temperature of the first flow region 15 can be kept high.

  In the above embodiment, the waste insertion port 28 is provided at a height position that partially overlaps with the waste 18 staying on the fluidized bed 14 in the vertical direction, and the waste 18 supplied from the waste insertion port 28 is provided. However, the waste staying on the upper surface of the fluidized bed 14 is positively moved in the lateral direction (on the first fluidized region 15 side). However, the present invention is not limited to this. That is, the fluidized bed furnace 10 may be configured so that the waste 18 can be supplied to a region adjacent to the front wall 24 on the fluidized bed 14. For example, as shown in FIGS. 8A and 8B, the waste insertion port 28 is located at a height near the upper surface of the fluidized bed 14 and the waste 18 staying on the fluidized bed 14. You may provide in the height position which inserts so that the new waste 18 may be mounted on it. In this case, for example, as shown in FIG. 8A, the waste insertion port 28 can supply new waste 18 laterally from a height position higher than the waste staying on the fluidized bed 14. As shown in FIG. 8B, it may be provided so that new waste 18 can be supplied downward from above the waste 18 staying on the fluidized bed 14. As described above, even if the waste 18 is supplied into the furnace body 20, the new flow 18 is supplied onto the staying waste 18, so that the pile of the waste 18 collapses and expands, thereby causing the second flow. Waste 18 enters the region 16 side. As a result, the waste 18 is sufficiently gasified while suppressing rapid fluctuations in the combustible gas recovered from the fluidized bed furnace 10, and as a result, the combustible gas can be stably generated from the waste 18. it can.

Moreover, in the said embodiment, when incombustible material stays in the vicinity of the mixture outlet 29 of the hearth (upper surface 21a of the bottom wall 21) and is not discharged | emitted outside, in order to discharge | emit this outside, it is 1st only for a fixed period. In the flow region 15, the fluidizing gas may be blown at a flow rate at which U _o / U _mf is 2 or more and less than 5. In this case, the fluidizing gas is not blown uniformly in the first flow region 15, but sequentially from the rear wall 25 side (left side in FIG. 1) to the front wall 24 side (right side in FIG. 1). It is preferable to gradually increase the supply amount of fluidized gas for each wind box 32. By such an operation, even if an incombustible material stays in the vicinity of the mixture outlet 29 of the hearth during normal operation, the incombustible material can be reliably discharged out of the furnace body 20. Since the above operation is performed for a very short time, the influence on the subsequent equipment can be minimized.

DESCRIPTION OF SYMBOLS 10 Fluidized bed furnace 12 Fluidized particle 14 Fluidized bed 15 1st fluidized zone 16 2nd fluidized zone 18 Waste 20 Furnace main body 21 Bottom wall 21a Upper surface 22 Side wall 24 Front wall (supply side wall)
25 Rear wall (opposite side wall)
29 Mixture outlet 50 Sand circulation device 60 Carbide insertion device

Claims (12)

A fluidized bed furnace that heats waste and takes out combustible gas from the waste,
Fluidized particles constituting a fluidized bed for heating waste,
A bottom wall that supports the fluidized particles from below and a side wall that rises from the bottom wall, the non-combustible material in the waste and the heating of the waste at a position deviated in a specific direction from the center position on the bottom wall A mixture outlet is provided for discharging the carbide generated by the above together with the fluidized particles, and the upper surface of the bottom wall is placed on the mixture so as to lower the fluidized particles on the upper surface of the bottom wall toward the mixture outlet. A furnace body that inclines so as to become lower toward the discharge port;
A gas supply unit that fluidizes the fluidized particles by blowing fluidized gas from the bottom wall of the furnace body toward the fluidized particles;
The waste is supplied to a region adjacent to the supply side wall on the fluidized bed from a supply side wall located on the same side as the mixture discharge port with respect to the center position of the bottom wall among the side walls, thereby A waste supply unit configured to move waste on the fluidized bed to the side of the opposite side wall located on the opposite side of the mixture discharge port across the center position of the bottom wall of the side wall;
A plurality of thermometers disposed above the fluidized bed;
An air supply unit capable of supplying air onto the fluidized bed ,
The gas supply unit forms a first fluidized region having a fluidization degree that allows waste to stay above the fluidized particles by blowing the fluidized gas from the periphery of the mixture discharge port. In addition, the fluidizing gas is blown between the first fluidizing region and the opposite side wall at a flow rate higher than the fluidizing gas blowing velocity in the first fluidizing region. The fluidized particles have a higher degree of fluidization than the fluidized region, whereby the fluidized particles convect and mix with the waste to form a second fluidized region that gasifies the waste,
The waste supply unit has the waste from the supply side wall so that the waste stays on the first flow region and the stayed waste sequentially enters the second flow region. There line the supply of waste with respect to the fluidized bed,
The plurality of thermometers are arranged at different positions above the first flow region,
The fluidized bed furnace in which the air supply unit supplies air onto the first fluidized region based on the index values of the plurality of thermometers so that the temperature in the furnace body increases . The fluidized bed furnace according to claim 1,
The waste supply unit pushes a new waste laterally from the supply side wall toward the waste staying on the first flow region, and thereby the waste staying on the first flow region. A fluidized bed furnace in which things sequentially enter the second fluidized zone. In the fluidized bed furnace according to claim 1 or 2,
A fluidized bed furnace comprising a carbide insertion device that separates carbide from the mixture of the incombustible material, the carbide, and the fluidized particles discharged from the mixture discharge port and returns the mixture to the fluidized bed from the opposite side wall. The fluidized bed furnace according to any one of claims 1 to 3,
When the minimum fluidization speed that is the minimum flow velocity of the fluidization gas for fluidizing the fluidized particles is U _mf and the average cross-sectional flow velocity of the fluidization gas is U ₀ , the gas supply unit is The fluidizing gas is blown at a flow rate where U ₀ / U _mf is 1 or more and less than 2 in the flow region of 1, and the flow rate of U ₀ / U _mf is 2 or more and less than 5 in the second flow region. A fluidized bed furnace that injects fluidized gas. The fluidized bed furnace according to any one of claims 1 to 4,
A fluidized bed furnace comprising a sand circulation device that separates the fluidized particles from the mixture discharged from the mixture discharge port and returns the separated fluidized particles into the furnace body. The fluidized bed furnace according to claim 5,
The sand circulation device is a fluidized bed furnace in which the fluidized particles separated from the mixture are returned onto the waste staying on the first fluidized zone. In a fluidized bed furnace given in any 1 paragraph of Claims 1 thru / or 6,
The fluidized bed furnace, wherein the furnace body has a planar shape in which a dimension in a width direction that is a direction orthogonal to a pushing direction of the waste by the waste supply unit is uniform in the pushing direction. The fluidized bed furnace according to claim 7,
The waste supply unit includes a pusher having a pushing surface extending in the width direction, and the pusher pushes the pusher so that the pushing surface of the pusher simultaneously pushes waste onto the fluidized bed over the entire width direction of the pushing surface. A fluidized bed furnace having a drive unit that reciprocates in a direction parallel to the direction. A waste treatment method for heating waste to take out combustible gas from the waste,
There are fluidized particles that constitute a fluidized bed for heating the waste, a bottom wall that supports the fluidized particles from below, and a sidewall that rises from the bottom wall, and the bottom wall has a specific direction from its center position. A mixture discharge port for discharging the non-combustible material in the waste and the carbide generated by heating the waste together with the fluidized particles is provided at a biased position on the upper surface of the bottom wall toward the mixture discharge port. Providing a fluidized bed furnace having a furnace body inclined so that the upper surface of the bottom wall is lowered toward the mixture discharge port so that the fluidized particles fall;
The degree of fluidization that allows waste to stay above the fluidized particles by blowing fluidized gas toward the fluidized particles from the region around the mixture outlet in the bottom wall of the furnace body. Between the first flow region and the opposite side wall located on the opposite side of the mixture outlet from the side wall with the center position of the bottom wall interposed therebetween. A second fluidized region having a higher degree of fluidization of the fluidized particles than the first fluidized region by blowing fluidized gas at a flow rate higher than the flow rate of fluidizing gas blown in the first fluidized region. Forming, and
The waste is supplied to a region adjacent to the supply side wall on the fluidized bed from a supply side wall located on the same side as the mixture discharge port with respect to the center position of the bottom wall among the side walls, thereby the said waste to dwell first flow region, and, viewed including the steps of gasifying wastes its residence by sequentially entering the second flow area, and
In the step of preparing the fluidized bed furnace, as the fluidized bed furnace, a plurality of thermometers arranged at different positions above the first fluidized area and air can be supplied onto the first fluidized area. And a further air supply unit,
A waste treatment method further comprising a step of supplying air from the air supply unit so that a temperature in the furnace body is increased based on index values of the plurality of thermometers . The waste disposal method according to claim 9, wherein
In the gasification step, new waste is pushed laterally from the supply side wall toward the waste staying on the first flow region, and thereby the waste staying on the first flow region. A waste treatment method in which an object is sequentially gasified by entering the second flow region. The waste disposal method according to claim 9 or 10,
A waste disposal method comprising a step of separating carbide from a mixture of the non-combustible material, the carbide, and the fluidized particles discharged from the mixture discharge port and returning the mixture to the fluidized bed from the opposite side wall. The waste treatment method according to any one of claims 9 to 11,
When the minimum fluidization speed that is the minimum flow velocity of the fluidizing gas for fluidizing the fluidized particles is U _mf and the average cross-sectional flow velocity of the fluidizing gas is U ₀ , U 1 in the first fluidized region _The fluidizing gas is injected at a flow rate at which ₀ / U _mf is 1 or more and less than 2, and the fluidizing gas is injected at a flow rate at which U ₀ / U _mf is 2 or more and less than 5 in the second flow region. , Waste disposal methods.

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