JP2020034213A - Wet biomass incineration system - Google Patents

Abstract

To make the system operable at a stable hearth temperature even when properties of wet biomass change by properly adjusting the travel of fluid medium which moves between a dry room and a combustion chamber in a wet biomass incineration system having an internal circulation fluidized bed incinerator.SOLUTION: A wet biomass incineration system comprises: a dry room and a combustion chamber; a fluid bed; a hearth supporting the fluid bed; a wet biomass incinerator in which an upper space of the fluid bed on the dry room side and an upper space of the fluid bed on the combustion chamber side are partitioned, and at least a part of the lower end has the hearth and a partition wall arranged in the fluid bed with a space therebetween; a first air box for supplying desiccant gas into the dry room; a second air box for supplying combustion agent gas into the combustion chamber; and a third air box arranged separately from the first air box and the second air box for supplying fluidization gas from below the fluid bed at a position vertically overlapping the space into the space.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wet biomass incineration system including an internal circulating fluidized bed wet biomass incinerator.

  BACKGROUND ART As a treatment facility for wet biomass such as sewage sludge, woody biomass, and garbage, for example, an incineration system including an incinerator of an internal circulation fluidized bed type is known. As disclosed in Patent Document 1, for example, this type of incinerator has a drying chamber and a combustion chamber, and a flow medium is provided below each of the drying chamber and the combustion chamber over the drying chamber and the combustion chamber. A flowing fluidized bed is provided.

  In the incinerator having the above configuration, the biomass is dried while being mixed with the fluidized medium by the desiccant gas supplied from below the fluidized bed into the drying chamber, and the high-temperature combustible gas supplied from below the fluidized bed into the combustion chamber. Thus, the biomass dried in the drying chamber is burned while being mixed with the fluid medium. Dry exhaust gas generated by drying biomass or combustion exhaust gas generated by combustion of biomass is heat-recovered and, for example, introduced into a power generation device provided outside the incinerator to be used for power generation.

JP-A-2006-138694

  By operating the incinerator having the above-described configuration at a stable hearth temperature, heat can be satisfactorily recovered while suppressing emissions of greenhouse gases and dioxins. Here, the moisture amount of the biomass supplied to the drying chamber and the calorific value per unit weight of the solid content (hereinafter, referred to as the property of the biomass) fluctuate to change the temperature of the fluidized bed in the drying chamber and the combustion chamber. If the temperature of the fluidized bed can be prevented from fluctuating, the system can be operated more stably, which is desirable.

  As a countermeasure against the above problem, for example, when the temperature of the fluidized bed in the drying chamber is excessively lowered, a method of increasing the moving amount of the fluidized medium can be considered. However, it is difficult to adjust the amount of movement of the fluid medium between the drying chamber and the combustion chamber. For example, heat loss of the combustion chamber may occur, or unnecessary decomposition of biomass may occur in the drying chamber.

  Therefore, the present invention provides a wet biomass incineration system having an internal circulating fluidized bed incinerator, in which the properties of the wet biomass can be improved by appropriately adjusting the moving amount of the fluid medium moving between the drying chamber and the combustion chamber. The purpose is to enable the system to operate at a stable hearth temperature even if it fluctuates.

  In order to solve the above problems, a wet biomass incineration system according to one embodiment of the present invention includes a drying chamber and a combustion chamber, and a fluidized bed including a fluid medium flowing under the drying chamber and below the combustion chamber, A hearth that supports the fluidized bed, a space above the fluidized bed on the drying chamber side, and a space above the fluidized bed on the combustion chamber side, and at least a part of the lower end connects the hearth and the space. A wet biomass incinerator having a partition wall disposed in the fluidized bed, and drying the mixed wet biomass with the fluidized medium in the drying chamber from below the fluidized bed on the drying chamber side. A first wind box for supplying the desiccant gas into the drying chamber, and mixing the wet biomass dried in the drying chamber with the fluid medium in the combustion chamber from below the fluidized bed on the combustion chamber side. What Wind box for supplying a combustible gas for burning from the inside of the combustion chamber, and the fluidized bed disposed separately from the first wind box and the second wind box at a position vertically overlapping the space. And a third wind box that supplies fluidized gas for moving the wet biomass and the fluidized medium between the drying chamber and the combustion chamber from the lower side into the space.

  According to the above configuration, since the third wind box is arranged separately from the first wind box and the second wind box, the flow rate of the fluidizing gas supplied into the space is reduced by the drying method for supplying the flow rate into the drying chamber. The flow rate of the propellant gas and the flow rate of the propellant gas supplied into the combustion chamber can be adjusted independently. Thereby, while maintaining the flow rate of the desiccant gas for properly drying the wet biomass in the drying chamber and the flow rate of the combustion gas for appropriately burning the biomass in the combustion chamber, the flow rate of the fluidizing gas is reduced. By adjusting, the moving amount of the fluid medium moving between the combustion chamber and the drying chamber can be appropriately adjusted.

  Therefore, even when the properties of the biomass supplied to the drying chamber fluctuate, the temperature of the fluidized bed in the drying chamber and the temperature in the combustion chamber are prevented while preventing unnecessary decomposition of biomass in the drying chamber and heat loss in the combustion chamber. The temperature of each fluidized bed can be stabilized.

  A desiccant gas supply path for supplying the desiccant gas to the first wind box, a combustible gas supply path for supplying the combustible gas to the second wind box, and a third wind box for supplying the fluidizing gas to the third wind box And a valve for adjusting a flow rate of the fluidizing gas flowing through the fluidizing gas supply path.

  According to the above configuration, the flow rate of the fluidizing gas supplied from the fluidizing gas supply path into the space, the flow rate of the desiccant gas supplied to the drying chamber, and the flow rate of the combustion gas supplied to the combustion chamber Can be adjusted relatively easily using valves.

  A plurality of gas supply units for supplying the fluidizing gas into the space are connected to the third wind box along a wall surface of the partition wall in a portion of the hearth vertically overlapping the space, and The valve may be arranged in a horizontal direction, and the valve may be arranged so as to be able to reduce a difference in flow rate of the fluidizing gas supplied into the space from each of the plurality of gas supply units.

  According to the above configuration, it is easy to uniformly supply the fluidizing gas into the space from each of the plurality of gas supply units provided in the horizontal direction along the wall surface of the partition wall.

  The third wind box includes a plurality of partition cells arranged in a horizontal direction along a wall surface of the partition wall, and in a portion vertically overlapping the space of the hearth, along a wall surface of the partition wall, The plurality of gas supply units that supply the fluidizing gas into the space are connected to each of the partition cells and provided in a row in a horizontal direction, and the valve corresponds to each of the plurality of partition cells. By being provided, the flow rate of the fluidizing gas supplied into the space via the partition cell may be individually adjustable for each of the partition cells.

  According to the above configuration, since the flow rate of the fluidizing gas can be individually adjusted by the valve for each partition cell of the third wind box, for example, in the space, the movement of the fluid medium between the drying chamber and the combustion chamber is promoted. A section and a section that does not promote the movement can be set separately. Therefore, the moving amount of the fluid medium moving between the combustion chamber and the drying chamber can be more finely adjusted.

  The fluidizing gas supply path may have a plurality of branch paths arranged at a downstream end thereof and branched from each other, and the plurality of branch paths may be individually connected to each of the plurality of partition cells. . As described above, by using the fluidizing gas supply path having a plurality of branch paths, the flow rate of the fluidizing gas can be adjusted by the valve for each partition cell with a relatively simple configuration.

  The thermometer may further include a thermometer that measures the temperature of the fluidized bed in the drying chamber, and a control unit that is connected to the thermometer and the valve to adjust the valve. According to the above configuration, for example, when the control unit determines that the measurement value of the thermometer is equal to or more than the predetermined value, the amount of movement of the fluid medium that moves between the combustion chamber and the drying chamber by adjusting the valve. Can be adjusted automatically.

  The partition wall may have a through portion disposed in the fluidized bed and formed at the lower end and penetrating in the thickness direction of the partition wall, and the space may be an internal space of the through portion. . According to the above configuration, the space can be efficiently arranged in the furnace by using the through portion of the partition wall.

  The penetrating portion is surrounded by the partition wall and the hearth, and when viewed from the thickness direction of the partition wall, the penetrating portion has a pair of sides parallel to a horizontal direction and a pair of sides parallel to a vertical direction. May have a rectangular peripheral edge shape having a side of According to the above configuration, since the peripheral shape of the penetrating portion is constant in the horizontal direction, the moving amount of the fluid medium moving through the penetrating portion can be easily adjusted by the flow rate of the fluidizing gas.

  According to each aspect of the present invention, in a wet biomass incineration system having an internal circulating fluidized bed incinerator, by appropriately adjusting the moving amount of a fluid medium moving between a drying chamber and a combustion chamber, the wet Even if the properties of biomass change, the system can be operated at a stable hearth temperature.

1 is an overall view of a wet biomass incineration system according to a first embodiment. It is a front view of the partition wall of FIG. 1, and its periphery. It is an operation | movement flowchart of the wet biomass incineration system of FIG. It is a perspective view of the partition in the wet biomass incineration system concerning a 2nd embodiment. It is a front view of the partition wall of FIG. 4, and its periphery. It is an operation | movement flowchart of the wet biomass incineration system of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, “flow rate” indicates the flow rate of gas supplied from the gas supply unit 6 per unit time, and “flow rate” indicates the flow rate of gas supplied from the gas supply unit 6 per unit time. Is shown. The “moving amount” indicates the moving amount of the fluidized medium 10 per unit time in the incinerator 2.

(1st Embodiment)
[Wet biomass incineration system]
FIG. 1 is an overall view of a wet biomass incineration system 1 (hereinafter, simply referred to as a system 1) according to an embodiment. FIG. 2 is a front view of the partition wall 2c of FIG. 1 and its periphery. As shown in FIGS. 1 and 2, the system 1 includes a wet biomass incinerator 2 (hereinafter simply referred to as an incinerator 2), a control unit 3, a wet biomass supply path R1, a desiccant gas supply path R2, and a combustion gas. A supply path R3, a fluidized gas supply path R4, a dry exhaust gas discharge path R5, a combustion exhaust gas discharge path R6, a combustion ash discharge path R7, a first valve V1, a second valve V2, and a third valve V3 are provided.

  The incinerator 2 includes a drying chamber 2a, a combustion chamber 2b, a partition wall 2c, a hearth 2d, upper spaces 21 and 22, a plurality of gas supply units 6, a fluidized bed 2f, a first wind box 7, a second wind box 9, It has a third wind box 8, a drying chamber thermometer T1, and a combustion chamber thermometer T2.

  The drying chamber 2a and the combustion chamber 2b are provided inside the incinerator 2 with a partition wall 2c therebetween. In the drying chamber 2a, the wet biomass 15 supplied from the biomass supply port 2a1 is dried. In the combustion chamber 2b, the wet biomass 15 dried in the drying chamber 2a is moved from the drying chamber 2a and burned. In addition, the wet biomass referred to in the present embodiment refers to a material containing a carbon component and having a water content of several tens% or more when supplied to the drying chamber 2a.

  The partition wall 2c partitions the space 21 above the fluidized bed 2f on the drying chamber 2a side and the space 22 above the fluidized bed 2f on the combustion chamber 2b side. At least a part of the lower end of the partition wall 2c is arranged in the fluidized bed 2f with the hearth 2d and the space 13 therebetween. Thereby, the upper spaces 21 and 22 in the incinerator 2 are isolated from each other. The hearth 2d supports the fluidized bed 2f. The fluidized bed 2f is disposed above the hearth 2d, below the drying chamber 2a, and below the combustion chamber 2b.

  The plurality of gas supply units 6 are uniformly distributed on the upper surface of the hearth 2d. Each of a portion vertically overlapping the drying chamber 2a of the hearth 2d, a portion vertically overlapping the combustion chamber 2b of the hearth 2d, and a portion vertically overlapping the space 13 of the hearth 2d includes a plurality of gases. The supply units 6 are respectively arranged. The gas supply unit 6 arranged in a part vertically overlapping the drying chamber 2 a of the hearth 2 d is connected to the first wind box 7. The gas supply unit 6 arranged in a part vertically overlapping the space 13 of the hearth 2 d is connected to the third wind box 8. The gas supply unit 6 arranged in a part vertically overlapping the combustion chamber 2 b of the hearth 2 d is connected to the second wind box 9.

  Since a portion of the hearth 2d vertically overlapping with the drying chamber 2a and a portion of the hearth 2d vertically overlapping with the combustion chamber 2b have a larger area than a portion of the hearth 2d vertically overlapping with the space 13, More gas supply units 6 are arranged than the part vertically overlapping the space 13 of the hearth 2d. The gas supply unit 6 is, for example, a nozzle unit having a plurality of gas ejection holes, but is not limited thereto.

  As shown in FIG. 2, the partition wall 2c of the present embodiment has a through portion 2g that is disposed in the fluidized bed 2f and formed at the lower end of the partition wall 2c and penetrates in the thickness direction of the partition wall 2c. The penetrating portion 2g is surrounded by the partition wall 2c and the hearth 2d. The through portion 2g of the present embodiment has a rectangular peripheral shape having a pair of sides parallel to the horizontal direction and a pair of sides parallel to the vertical direction when viewed from the thickness direction of the partition wall 2c. The space 13 is an internal space of the through portion 2g.

  A plurality of gas supply units 6 for supplying fluidized gas into the space 13 are connected to the third wind box 8 along a wall surface of the partition wall 2c at a portion vertically overlapping the space 13 of the hearth 2d. In addition, they are provided side by side in the horizontal direction. The third valve V3 described below is arranged so as to reduce the difference in the flow rate of the fluidizing gas supplied into the space 13 from each of the plurality of gas supply units 6 arranged in the space 13.

  The fluidized bed 2f shown in FIG. 1 includes a fluidized medium (particulate matter) 10 flowing below the drying chamber 2a and below the combustion chamber 2b. The fluid medium 10 is, for example, silica sand, but is not limited thereto. During the operation of the incinerator 2, the temperature of the fluidized bed 2f in the drying chamber 2a is set to a value in a temperature range lower than the thermal decomposition temperature of the wet biomass 15 (for example, a value in a range of 160 ° C. or lower), and the combustion chamber 2b The temperature of the fluidized bed 2f is set higher than the temperature of the fluidized bed 2f in the drying chamber 2a (for example, a value in a temperature range of 500 ° C. or more and 800 ° C. or less).

  Each of the wind boxes 7 to 9 is a hollow box body. The first wind box 7 is provided below the hearth 2d on the drying chamber 2a side. The first wind box 7 supplies a desiccant gas for drying the wet biomass 15 while mixing it with the fluidized medium 10 in the drying chamber 2a from below the fluidized bed 2f on the drying chamber 2a side into the drying chamber 2a. .

  The second wind box 9 is provided below the hearth 2d on the combustion chamber 2b side. The second wind box 9 is a combustion gas for burning the wet biomass 15 dried in the drying chamber 2a while mixing with the fluid medium 10 in the combustion chamber 2b from below the fluidized bed 2f on the combustion chamber 2b side. Is supplied into the combustion chamber 2b.

  The third wind box 8 is provided below the hearth 2d at a position vertically overlapping the partition wall 2c. The third wind box 8 supplies a fluidizing gas for moving the fluid medium 10 and the wet biomass 15 between the drying chamber 2a and the combustion chamber 2b from below the fluidized bed 2f at a position overlapping the space 13 in the vertical direction. It is supplied into the space 13.

  Here, the area of the part vertically overlapping the space 13 of the hearth 2d is the area of the part vertically overlapping the drying chamber 2a of the hearth 2d, and the part vertically overlapping the combustion chamber 2b of the hearth 2d. Is sufficiently smaller than the area of Therefore, compared to the flow rate of the desiccant gas supplied into the drying chamber 2a and the flow rate of the combustible gas supplied into the combustion chamber 2b, the flow rate of the fluidizing gas supplied into the space 13 is usually Is small enough.

  The wet biomass supply path R1 is connected to the biomass supply port 2a1, and supplies the wet biomass 15 into the drying chamber 2a. The desiccant gas supply passage R2 supplies a desiccant gas for drying the wet biomass 15 while mixing the wet biomass 15 with the fluid medium 10 in the drying chamber 2a. The desiccant gas supply path R <b> 2 is connected to the first wind box 7. The desiccant gas is, but is not limited to, superheated steam.

  The combustion agent gas supply path R3 supplies a combustion agent gas for burning the wet biomass 15 dried in the drying chamber 2a while mixing with the fluid medium 10 in the combustion chamber 2b. The combustion agent gas supply path R3 is connected to the second wind box 9. The combustible gas is air, but is not limited to air.

  The fluidizing gas supply path R4 is arranged separately from the desiccant gas supply path R2 and the combustion agent gas supply path R3, and supplies the fluidizing gas to the third wind box 8. The fluidizing gas supply path R <b> 4 is connected to the third wind box 8. The fluidizing gas is, but is not limited to, superheated steam. The fluidizing gas may be a different gas than the desiccant gas and the combustion gas.

  The drying exhaust gas discharge path R5 discharges the drying exhaust gas generated by drying the wet biomass 15 in the upper space 21 to the outside of the drying chamber 2a. The drying exhaust gas discharge path R5 is connected to the drying chamber 2a. The flue gas discharge passage R6 discharges flue gas generated by burning the wet biomass 15 in the upper space 22 to the outside of the combustion chamber 2b. The flue gas discharge passage R6 is connected to the combustion chamber 2b. The combustion ash discharge path R7 discharges the combustion ash generated by the combustion of the wet biomass 15 to the outside of the combustion chamber 2b. The combustion ash discharge path R7 is connected to the combustion chamber 2b.

  The first valve V1 adjusts the flow rate of the desiccant gas flowing through the desiccant gas supply path R2. The second valve V2 regulates the flow rate of the combustion gas flowing through the combustion gas supply passage R3. The third valve V3 adjusts the flow rate of the fluidizing gas flowing through the fluidizing gas supply path R4.

  The drying room thermometer T1 is disposed in the drying room 2a and measures the temperature of the fluidized bed 2f in the drying room 2a. The combustion chamber thermometer T2 is arranged in the combustion chamber 2b and measures the temperature of the fluidized bed 2f in the combustion chamber 2b.

  The control unit 3 is, for example, a computer including a CPU, a ROM, a RAM, and the like, and individually controls the opening degrees of the valves V1 to V3. A predetermined control program is stored in the ROM. The control unit 3 monitors the measured values of the thermometers T1 and T2 based on the control program, and adjusts the opening of the valves V1 to V3 at a predetermined timing.

  The heat exchange device 4 recovers heat from the combustion exhaust gas. The heat exchange device 4 heat-exchanges the combustion agent gas with the combustion exhaust gas discharged from the combustion chamber 2b before supplying the combustion agent gas to the combustion chamber 2b, raises the temperature of the combustion agent gas, and heat-exchanges water with the combustion exhaust gas. To generate superheated steam.

  As an example, the heat exchange device 4 includes a preheater 16 and a boiler 17. The preheater 16 heat-exchanges the combustion gas with the combustion exhaust gas in advance before supplying the combustion gas supplied to the combustion chamber 2b to the combustion chamber 2b to increase the temperature. The boiler 17 performs heat exchange between water and combustion exhaust gas flowing through the preheater 16 to generate superheated steam (desiccant gas).

  The power generator 5 is provided in the drying exhaust gas discharge path R5. The power generation device 5 is a heat recovery device that recovers heat from the dried exhaust gas. The power generator 5 is, for example, a binary generator, but is not limited to this. Further, the heat recovery device may be other than the power generation device, and may have, for example, a boiler.

  During the operation of the incinerator 2, the desiccant gas that has passed through the desiccant gas supply path R2 is ejected from the gas supply units 6 disposed on the drying chamber 2a side into the drying chamber 2a via the first wind box 7. Is done. The desiccant gas is mixed into the fluid medium 10 and the wet biomass 15 as a plurality of bubbles 14. The wet biomass 15 is dried while being mixed with the fluidized medium 10 by the desiccant gas ejected from each gas supply unit 6. The wet biomass 15 thus dried moves together with the fluid medium 10 from the drying chamber 2a to the combustion chamber 2b.

  The drying exhaust gas in the upper space 21 flows through the drying exhaust gas discharge path R5 and is discharged outside the drying chamber 2a. When a non-oxidizing gas such as superheated steam is used as the desiccant gas, the wet biomass 15 does not burn in the drying chamber 2a, and the dry exhaust gas is prevented from containing a carbon component.

  During operation of the incinerator 2, the combustion gas passing through the combustion gas supply passage R3 from each gas supply unit 6 arranged on the combustion chamber 2b side enters the combustion chamber 2b via the second wind box 9. It is gushing. The combustion agent gas is mixed into the fluid medium 10 and the wet biomass 15 as a plurality of bubbles 14. The wet biomass 15 is burned while being mixed with the fluid medium 10 by the combustible gas ejected from each gas supply unit 6.

  The combustion exhaust gas in the upper space 22 is discharged to the outside of the combustion chamber 2b through the exhaust gas discharge passage R6. The combustion ash flows through the combustion ash discharge passage R7 and is discharged to the outside of the combustion chamber 2b. The heat generated by the combustion of the wet biomass 15 in the combustion chamber 2b moves from the combustion chamber 2b side to the drying chamber 2a together with the fluidized medium 10, and is used for drying the wet biomass 15 in the drying chamber 2a.

  When the incinerator 2 is operated, fluidizing gas that has passed through the fluidizing gas supply path R4 is ejected from the gas supply units 6 disposed in the space 13 into the space 13 via the third wind box 8. You. The fluidizing gas is mixed into the fluid medium 10 and the wet biomass 15 as a plurality of bubbles 14. The fluidized gas ejected from each gas supply unit 6 arranged in the space 13 causes the fluidized medium 10 and the wet biomass 15 in the space 13 to be in a fluidized state, and moves between the drying chamber 2a and the combustion chamber 2b.

[System operation method]
FIG. 3 is an operation flowchart of the system 1 of FIG. In the system 1, as initial settings, the opening of the first valve V1 and the second valve V2 is controlled to a predetermined value (here, 100%), and the opening of the third valve V3 is greater than 0% and less than 100%. Is controlled to a value M1 in the range of The value M1 can be set as appropriate, and is, for example, a value in a range of 50% or more and less than 100%.

  As shown in FIG. 3, in the operating system 1, the control unit 3 first determines whether or not the measured value of the drying room thermometer T1 is less than the threshold value A1 based on the control program (S1). In step S1, the control unit 3 changes the state of the third valve V3 when determining that the measured value of the drying chamber thermometer T1 is not less than the threshold value A1 (that is, not less than the threshold value A1) (S1: N). Maintain (S3).

  Thereby, in the incinerator 2, the flow rate of the fluidizing gas supplied into the space 13 via the third wind box 8 (in other words, the opening degree of the third valve V3) is maintained at a predetermined value, and the combustion chamber 2b A change in the amount of movement of the fluidized medium 10 with the drying chamber 2a is prevented.

  Therefore, for example, the movement of a relatively large amount of the fluid medium 10 at high temperature from the combustion chamber 2b to the drying chamber 2a is prevented. This prevents the temperature inside the drying chamber 2a from excessively rising and also prevents the heat loss of the combustion chamber 2b. Further, the thermal decomposition of the wet biomass 15 in the drying chamber 2a is prevented, and the carbon component is prevented from being mixed into the dry exhaust gas.

  On the other hand, in step S1, when the control unit 3 determines that the measurement value of the drying room thermometer T1 is less than the threshold value A1 (S1: Y), the control unit 3 controls to further open the valve V3 for a certain time ( S2). Here, as an example, the control unit 3 controls the opening of the valve V3 to a value M2 (for example, 100%) larger than the value M1.

  Thereby, in the incinerator 2, the flow rate of the fluidizing gas supplied into the space 13 via the third wind box 8 increases, and the movement of the high-temperature fluid medium 10 moving from the combustion chamber 2b side to the drying chamber 2a side. The amount increases. Therefore, the temperature in the drying chamber 2a is prevented from being excessively lowered, and the wet biomass 15 is dried stably. Further, the dried exhaust gas generated in the drying chamber 2a is sent to the power generator 5 through the dried exhaust gas discharge path R5, and the heat is well recovered.

  As described above, the control unit 3 determines whether to control the valve V3 by comparing the measured value of the drying room thermometer T1 with the threshold value A1, and controls the valve V3 according to the determination result. Thereby, even if the property of the wet biomass 15 changes, the system 1 can be operated at a stable hearth temperature.

  Next, the control unit 3 determines whether or not the system 1 is in the operation suspension state (S4). In step S4, the control unit 3 repeats steps S1 to S4 until it determines that the system 1 is in the operation suspension state.

  As described above, according to the system 1, since the third wind box 8 is disposed separately from the first wind box 7 and the second wind box 9, the third wind box 8 is provided with the fluidized gas supplied into the space 13. The flow rate can be adjusted independently of the flow rate of the desiccant gas supplied into the drying chamber 2a and the flow rate of the combustion gas supplied into the combustion chamber 2b. Thereby, while maintaining the flow rate of the desiccant gas for appropriately drying the wet biomass 15 in the drying chamber 2a and the flow rate of the combustion agent gas for appropriately burning the biomass in the combustion chamber 2b, the flow rate is maintained. By adjusting the flow rate of the forming gas, the amount of movement of the fluid medium 10 moving between the combustion chamber 2b and the drying chamber 2a can be appropriately adjusted.

  Therefore, even when the properties of the wet biomass 15 supplied into the drying chamber 2a fluctuate, the unnecessary decomposition of the wet biomass 15 in the drying chamber 2a and the heat loss in the combustion chamber 2b are prevented while the inside of the drying chamber 2a is prevented. And the temperature of the fluidized bed 2f in the combustion chamber 2b can be stabilized.

  The part of the hearth 2d where the fluidizing gas is supplied into the space 13 is a part that vertically overlaps the drying chamber 2a of the hearth 2d and a part that vertically overlaps the combustion chamber 2b of the hearth 2d. The area is smaller than that. Therefore, the flow rate of the fluidizing gas supplied into the space 13 is smaller than the flow rate of the desiccant gas supplied into the drying chamber 2a and the flow rate of the combustible gas supplied into the combustion chamber 2b. .

  By supplying the fluidizing gas into the space 13 under such conditions, the amount of movement of the fluidizing medium 10 moving between the combustion chamber 2b and the drying chamber 2a can be reduced by a relatively small amount of the fluidizing gas. Can be adjusted well and properly. Further, the temperature in the incinerator 2 can be stabilized while suppressing the fluctuation of the air-fuel ratio of the gas in the incinerator 2. Further, by using the same gas as the desiccant gas as the fluidizing gas, even if the fluidizing gas enters the drying chamber 2a, it is possible to prevent the composition change of the drying exhaust gas.

  Further, since the system 1 includes the desiccant gas supply path R2, the combustion agent gas supply path R3, the fluidizing gas supply path R4, and the third valve V3, the system 1 supplies the gas into the space 13 from the fluidizing gas supply path R4. Using the third valve V3, the flow rate of the fluidizing gas to be supplied is relatively independent of the flow rate of the desiccant gas supplied into the drying chamber 2a and the flow rate of the combustion gas supplied into the combustion chamber 2b. Can be easily adjusted.

  Further, in a part of the hearth 2 d vertically overlapping the space 13, a plurality of gas supply units 6 are connected to the third wind box 8 and provided in a horizontal direction along the wall surface of the partition wall 2 c, The valve V3 is arranged so as to reduce the difference in the flow rate of the fluidizing gas supplied into the space 13 from each of the plurality of gas supply units 6. For this reason, it is easy to uniformly supply the fluidizing gas into the space 13 from each of the plurality of gas supply units 6 provided in the horizontal direction along the wall surface of the partition wall 2c. This makes it easy to appropriately adjust the amount of movement of the fluid medium 10 moving in the space 13.

  The system 1 also includes a drying room thermometer T1 for measuring the temperature of the fluidized bed 2f in the drying room 2a, and a control unit 3 connected to the drying room thermometer T1 and the valve V3 to adjust the valve V3. Therefore, for example, when the control unit 3 determines that the measurement value of the drying chamber thermometer T1 is equal to or more than a predetermined value, the flow moving between the combustion chamber 2b and the drying chamber 2a by adjusting the valve V3. The moving amount of the medium 10 can be automatically adjusted.

  The partition wall 2c is disposed in the fluidized bed 2f so as to partition the hearth 2d, and has a penetrating portion 2g formed at the lower end of the partition wall 2c and penetrating in the thickness direction of the partition wall 2c. , The inner space of the penetrating portion 2g. For this reason, the space 13 can be efficiently arranged in the incinerator 2 by using the penetration portion 2g of the partition wall 2c.

  The penetrating portion 2g is surrounded by the partition wall 2c and the hearth 2d, and when viewed from the thickness direction of the partition wall 2c, the penetrating portion 2g has a pair of sides parallel to the horizontal direction and a pair of sides parallel to the vertical direction. It has a rectangular peripheral shape having a pair of sides. Thereby, since the peripheral shape of the through portion 2g is constant in the horizontal direction, the movement amount of the fluid medium 10 moving through the through portion 2g can be easily adjusted by the flow rate of the fluidizing gas.

(Modification of First Embodiment)
In the first modification of the first embodiment, in step S1, the control unit 3 determines whether the measured value of the thermometer T1 is less than the threshold value A1 and the measured value of the thermometer T2 is not less than the threshold value B1. Is determined. That is, in step S1, the control unit 3 determines that the measured value of the drying chamber thermometer T1 is less than the threshold value A1 and that the measured value of the combustion chamber thermometer T2 is not less than the threshold value B1 (S1: Y), proceed to step S2; otherwise (S1: N), proceed to step S3.

  According to the first modification, the same effect as that of the first embodiment can be obtained. Further, in step S2, when moving the fluid medium 10 from the combustion chamber 2b side to the drying chamber 2a side, the high temperature fluid medium 10 heated to the threshold B1 or more is moved, and the temperature in the drying chamber 2a is reduced. Can be raised well.

  In the second modification of the first embodiment, in step S1, the control unit 3 determines whether or not the measured value of the drying room thermometer T1 is equal to or larger than a threshold value A2. As an example, the threshold A2 is set to a value equal to or less than the threshold A1.

  In step S1, when the control unit 3 determines that the measurement value of the drying room thermometer T1 is equal to or larger than the threshold value A2 (S1: Y), the control unit 3 proceeds to step S3. In step S1, when the control unit 3 determines that the measurement value of the drying room thermometer T1 is not equal to or more than the threshold value A2 (that is, less than the threshold value A2) (S1: N), the control unit 3 proceeds to step S2. According to the second modification, the same effect as that of the first embodiment can be obtained. Hereinafter, other embodiments will be described focusing on differences from the first embodiment.

(2nd Embodiment)
FIG. 4 is a perspective view of a partition wall 2c in the wet biomass incineration system according to the second embodiment. FIG. 5 is a front view of the partition wall 2c of FIG. 4 and its periphery. As shown in FIGS. 4 and 5, the space 13 includes a plurality of sections (here, three sections 13a to 13c) arranged in a horizontal direction along the wall surface of the partition wall 2c. In the space 13, a plurality of gas supply units 6 are provided corresponding to the plurality of sections 13a to 13c. The gas supply unit 6 is, for example, a nozzle unit similar to that of the first embodiment.

  The third wind box 18 corresponds to the third wind box 8 of the first embodiment, and includes a plurality of partition cells (here, three partition cells 18a to 18c) arranged in a horizontal direction along the wall surface of the partition wall 2c. . The partition cell 18a corresponds to the section 13a, the partition cell 18b corresponds to the section 13b, and the partition cell 18c corresponds to the section 13c. The plurality of gas supply units 6 are connected to each of the division cells 18a to 18c. Thereby, in the part of the hearth 2 d vertically overlapping the space 13, the plurality of gas supply units 6 for supplying the fluidizing gas into the space 13 are provided along the wall surface of the partition wall 2 c by the partition cells 18 a to 18 c. And are provided side by side in the horizontal direction.

  A plurality of valves (here, valves V4 to V6) are provided as third valves in the fluidizing gas supply path R4. The valves V4 to V6 are provided corresponding to each of the plurality of division cells 18a to 18c. The valve V4 corresponds to the partition cell 18a, the valve V5 corresponds to the partition cell 18b, and the valve V6 corresponds to the partition cell 18c. Accordingly, in the system, the flow rate of the fluidizing gas supplied into the space 13 via the partition cells 18a to 18c can be adjusted for each of the partition cells 18a to 18c.

  Specifically, the fluidizing gas supply path R4 includes a main flow path 20, and a plurality of branch paths 20a to 20c that are continuous with the main flow path 20 and arranged at the downstream end of the fluidization gas supply path R4 and branched from each other. Having. The plurality of branch paths 20a to 20c are individually connected to the plurality of partition cells 18a to 18c, respectively. The branch path 20a corresponds to the section 13a and is connected to the partition cell 18a. The branch path 20b corresponds to the section 13b and is connected to the partition cell 18b. The branch path 20c corresponds to the section 13c and is connected to the partition cell 18c.

  The valve V4 is provided in the branch 20a, the valve V5 is provided in the branch 20b, and the valve V6 is provided in the branch 20c. The opening degrees of the valves V4 to V6 are individually controlled by the control unit 3. The valves V4 to V6 are arranged so that the flow rates of the fluidizing gas supplied from the plurality of gas supply units 6 into the sections 13a to 13c can be individually adjusted for each of the sections 13a to 13c.

  FIG. 6 is an operation flowchart of the system of FIG. In the system, as initial settings, the opening degrees of the first valve V1 and the second valve V2 are controlled to a predetermined value (here, 100%), and the opening degrees of the valves V4 to V6 are greater than 0% and less than 100%. It is controlled to the range value M1. The value M1 is the same as that of the first embodiment.

  As shown in FIG. 6, in the operating system, the control unit 3 first determines whether or not the measured value of the drying room thermometer T1 is less than the threshold value A3 based on the control program (S11). In step S11, when the control unit 3 determines that the measurement value of the drying room thermometer T1 is not less than the threshold value A3 (that is, is equal to or more than the threshold value A3) (S11: N), the control unit 3 selects one of the valves V4 to V6. Control is performed to reduce the opening of the specific valve (S12). Here, as an example, the control unit 3 controls the opening degrees of the valves V4 and V6 to be smaller than the opening degree of the valve V5.

  Thereby, in the incinerator 2, the fluidity of the fluid medium 10 in the sections 13a and 13c in the space 13 is reduced. On the other hand, the fluidity of the fluid medium 10 in the section 13b in the space 13 is maintained. Thereby, the movement of the fluid medium 10 between the drying chamber 2a and the combustion chamber 2b is substantially limited to only the section 13b, and the movement of the high-temperature fluid medium 10 moving from the combustion chamber 2b side to the drying chamber 2a side. The amount is reduced. This prevents the temperature inside the drying chamber 2a from excessively rising and also prevents the heat loss of the combustion chamber 2b. Further, the thermal decomposition of the wet biomass 15 in the drying chamber 2a is prevented, and the carbon component is prevented from being mixed into the dry exhaust gas.

  On the other hand, in step S11, when it is determined that the measurement value of the drying room thermometer T1 is less than the threshold value A3 (S11: Y), the control unit 3 maintains the state of the valves V4 to V6 (S13). Thus, in the incinerator 2, the flow rate of the fluidizing gas supplied into the space 13 is maintained, and the moving amount of the high-temperature fluid medium 10 moving from the combustion chamber 2b to the drying chamber 2a is maintained. Therefore, the temperature in the drying chamber 2a is prevented from being excessively reduced.

  Next, the control unit 3 determines whether or not the system is in the operation suspension state (S14). In step S14, the control unit 3 repeats steps S11 to S14 until it determines that the system is in the operation suspension state.

  According to the system having the above configuration, the flow rate of the fluidizing gas can be adjusted by the valves V4 to V6 for each of the division cells 18a to 18c of the third wind box 18. Therefore, for example, in the space 13, a section for promoting the movement of the fluid medium 10 between the drying chamber 2a and the combustion chamber 2b and a section for not promoting the movement can be set separately. Therefore, the movement amount of the fluid medium 10 moving between the combustion chamber 2b and the drying chamber 2a can be adjusted more finely.

  The fluidizing gas supply passage R4 has a plurality of branch passages 20a to 20c arranged at the downstream end thereof and branched from each other. The plurality of branch paths 20a to 20c are individually connected to the plurality of partition cells 18a to 18c, respectively. Therefore, by using the fluidizing gas supply path R4 having the plurality of branch paths 20a to 20c, the flow rate of the fluidizing gas can be adjusted by the valves V4 to V6 for each of the partition cells 18a to 18c with a relatively simple configuration. .

(Modification of Second Embodiment)
In a modified example of the second embodiment, in step S11, the control unit 3 determines whether the measured value of the thermometer T1 is equal to or larger than a threshold value A4. As an example, the threshold A4 is set to a value equal to or less than the threshold A3.

  In step S11, when the control unit 3 determines that the measurement value of the drying room thermometer T1 is equal to or larger than the threshold value A4 (S11: Y), the control unit 3 proceeds to step S12. In step S11, when the control unit 3 determines that the measurement value of the drying room thermometer T1 is not equal to or larger than the threshold value A4 (that is, smaller than the threshold value A4) (S11: N), the process proceeds to step S13. According to this modification, the same effect as in the second embodiment can be obtained.

  The present invention is not limited to each embodiment, and its configuration and method can be changed, added, or deleted without departing from the spirit of the present invention. The opening degree of at least one of the valves V1 to V6 may be manually controlled by a driver of the wet biomass incineration system. Further, the opening degrees of the valves V1 to V6 may be adjusted by a flow rate indicating controller (FIC).

  Further, in the section in which the opening degree of the valve is reduced in step S12, it is not necessary to completely stop the fluidity of the fluid medium 10, and the fluidity may be reduced as compared to before the control in step S12. Further, the section for reducing the opening degree of the valve in step S12 may be any one of the left and right ends of the through portion 2g or a section other than the left and right ends when viewed from the thickness direction of the partition wall 2c. .

R2 Desiccant gas supply path R3 Burnant gas supply path R4 Fluidizing gas supply path T1 Drying room thermometer V3 to V6 Valve 1 Wet biomass incineration system 2 Wet biomass incinerator 2a Drying room 2b Combustion room 2c Partition wall 2d Furnace floor 2f Fluidized bed 2g Penetration unit 3 Control unit 6 Gas supply unit 7 First wind box 8, 18 Third wind box 9 Second wind box 10 Fluid medium 13 Space 15 Wet biomass 18a to 18c Partition cell

Claims (8)

A drying chamber and a combustion chamber, a fluidized bed containing a fluidized medium flowing below the drying chamber and below the combustion chamber, a hearth supporting the fluidized bed, and above the fluidized bed on the drying chamber side A wet biomass incinerator comprising a space and a space above the fluidized bed on the combustion chamber side, and at least a part of a lower end having a furnace wall and a partition wall arranged in the fluidized bed with a space therebetween; ,
A first wind box that supplies a desiccant gas for drying while mixing wet biomass with the fluidized medium in the drying chamber from below the fluidized bed on the drying chamber side,
A second supplying a combustion agent gas into the combustion chamber for burning the wet biomass dried in the drying chamber with the fluidized medium in the combustion chamber from below the fluidized bed on the combustion chamber side; Wind box,
The wet biomass and the fluidized fluid are disposed separately from the first wind box and the second wind box and between the drying chamber and the combustion chamber from below the fluidized bed at a position vertically overlapping the space. A third wind box for supplying a fluidizing gas for moving the medium into the space, the incineration system for wet biomass. A desiccant gas supply path for supplying the desiccant gas to the first wind box;
A combustion gas supply path for supplying the combustion gas to the second wind box;
A fluidizing gas supply path for supplying the fluidizing gas to the third wind box;
The wet biomass incineration system according to claim 1, further comprising: a valve for adjusting a flow rate of the fluidizing gas flowing through the fluidizing gas supply path. A plurality of gas supply units for supplying the fluidizing gas into the space are connected to the third wind box along a wall surface of the partition wall in a portion of the hearth vertically overlapping the space, and Provided side by side in the horizontal direction,
The wet biomass incineration system according to claim 2, wherein the valve is arranged so as to be able to reduce a difference in flow rate of the fluidizing gas supplied into the space from each of the plurality of gas supply units. The third wind box includes a plurality of partition cells arranged in a horizontal direction along a wall surface of the partition wall,
In a portion of the hearth that vertically overlaps the space, the plurality of gas supply units that supply the fluidizing gas into the space are connected to each of the partition cells along a wall surface of the partition wall. And are provided side by side in the horizontal direction,
Since the valve is provided corresponding to each of the plurality of compartment cells, the flow rate of the fluidizing gas supplied into the space via the compartment cells is individually set for each of the compartment cells. 3. The wet biomass incineration system of claim 2, wherein the system is adjustable. The fluidizing gas supply passage has a plurality of branch passages arranged at the downstream end thereof and branched from each other,
The wet biomass incineration system according to claim 4, wherein the plurality of branch paths are individually connected to each of the plurality of compartment cells. A thermometer that measures the temperature of the fluidized bed in the drying chamber,
The wet biomass incineration system according to any one of claims 2 to 5, further comprising: a controller connected to the thermometer and the valve to adjust the valve. The partition wall has a penetrating portion disposed in the fluidized bed and formed at the lower end and penetrating in the thickness direction of the partition wall,
The wet biomass incineration system according to any one of claims 1 to 6, wherein the space is an internal space of the penetration portion. The penetration is surrounded by the partition wall and the hearth,
The wet according to claim 7, wherein the penetration portion has a rectangular peripheral shape having a pair of sides parallel to a horizontal direction and a pair of sides parallel to a vertical direction when viewed from a thickness direction of the partition wall. Biomass incineration system.

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