JP6553877B2 - Wet biomass incineration system - Google Patents

Description

  The present invention relates to a wet biomass incineration system.

  Conventionally, as a facility for treating wet biomass such as sewage sludge or wood-based material, a wet biomass incineration system including, for example, an incinerator and a power generation device that generates electric power by the exhaust gas from the incinerator is known.

  As a type of incinerator, for example, an internal circulating fluidized bed type can be mentioned. This type of incinerator has, for example, a drying / pyrolysis chamber and a combustion chamber as disclosed in Patent Document 1. Below each of the drying and thermal decomposition chamber and the combustion chamber, there is provided a fluidized bed in which a fluidized medium flows. In the drying and thermal decomposition chamber, the wet biomass is dried while being mixed with the fluid medium with a high temperature desiccant gas supplied from below the fluidized bed to form dry biomass. In the combustion chamber, dry biomass is combusted while being mixed with the fluidized medium with a high-temperature oxidant gas supplied from below the fluidized bed.

  In the drying / pyrolysis chamber, dry biomass may be pyrolyzed. The gas generated by this thermal decomposition is discharged out of the drying / pyrolysis chamber, for example, and is recovered by using a power recovery device such as a power generation device.

JP, 2006-275442, A

  The wet biomass incineration system is required to have a low running cost and to be operated with good combustion efficiency. Therefore, it is desirable that the heat recovery efficiency of the wet biomass incineration system be good. In addition, since the wet biomass incineration system is configured on a certain scale, it is also required to reduce equipment costs.

  However, in the system described in Patent Document 1, when heat recovery is performed using a power recovery device such as a power generator from the gas generated by pyrolysis in the drying / pyrolysis chamber, the gas is supplied to the power recovery device. Prior to this, a process of removing components such as steam is performed. This may result in loss of heat recovery.

  Then, an object of the present invention is to provide a wet biomass incineration system that can be operated at low running cost and good combustion efficiency by suppressing the loss of heat recovery of the power generation apparatus, and can reduce equipment cost.

  In order to solve the above problems, a wet biomass incineration system according to an aspect of the present invention includes a drying chamber and a combustion chamber in which a space above the hearth is partitioned by partition walls, and a lower portion in the drying chamber An incinerator provided with a fluidized bed in which a fluidized medium flows, a power generation apparatus generating electric power using exhaust gas of the incinerator, and a lower part of the fluidized bed on the drying chamber side A superheated steam supply passage for supplying superheated steam for drying while mixing wet biomass with the fluid medium in the drying chamber into the drying chamber, and connected below the fluid bed on the combustion chamber side, Connected to the drying chamber, an oxidizing gas supply path for supplying an oxidizing gas into the combustion chamber for burning the dry biomass produced by drying the biomass while mixing with the fluid medium in the combustion chamber And a superheated steam discharge passage that discharges the superheated steam used for drying the wet biomass to the power generation device and discharges the superheated steam to the power generation device, and the temperature of the fluidized bed in the dry chamber is the temperature of the dry biomass. The exhaust gas is set to a temperature lower than the thermal decomposition temperature, and the exhaust gas is superheated steam flowing through the superheated steam discharge path.

  According to the above configuration, by setting the temperature of the fluidized bed in the drying chamber to less than the thermal decomposition temperature of the dry biomass, thermal decomposition of the dried biomass in the drying chamber can be prevented, and the drying chamber is discharged to the superheated steam discharge passage The superheated steam can be prevented from mixing with the gas generated by the thermal decomposition of dry biomass. As a result, the superheated steam of high purity is supplied to the power generation apparatus through the superheated steam discharge path, so that the process of removing the impurity component of the gas supplied to the power generation apparatus in advance becomes unnecessary. Therefore, heat can be recovered using substantially all of the gas flowing through the superheated steam discharge passage. Accordingly, it is possible to stably generate power with high power generation efficiency by effectively using the latent heat rich in superheated steam while suppressing loss of heat recovery.

  In addition, since the superheated steam is less likely to contaminate the power generation device and the exhaust gas flow passage as compared with the gas or the like generated due to the thermal decomposition of the dry biomass, it is possible to prevent the power generation device from being contaminated and reducing the power generation efficiency. As a result, the incinerator can be operated with good combustion efficiency, and the running cost of the wet biomass incineration system can be reduced. Further, by integrally configuring the incinerator so as to have a drying chamber and a combustion chamber, the incinerator can be configured in a compact manner, and facility costs can be suppressed.

  Connected to the incinerator, connected to the first wet biomass supply passage for supplying the wet biomass directly into the drying chamber, and the superheated steam discharge passage, and the wet biomass via a part of the superheated steam discharge passage And a second wet biomass feed path for feeding into the drying chamber.

  According to the above configuration, the wet biomass can be dispersed and supplied from the plurality of positions into the drying chamber through the first and second wet biomass supply channels, and the wet biomass can be efficiently dried rapidly with the superheated steam. Moreover, it is possible to prevent the wet biomass from being locally deposited in the drying chamber, and to suppress the load on the hearth of the drying chamber.

  The incinerator extends from the lower side of the fluidized bed on the combustion chamber side to a height lower than the bed height of the fluidized bed in the combustion chamber, inside the fluidized bed on the combustion chamber side near the drying chamber. You may have further the partition wall provided in.

  Thus, the partition wall can further prevent the combustion gas or the oxidizing gas in the combustion chamber from flowing into the drying chamber and mixing in the overheated steam, and the power generation efficiency of the power generation apparatus that generates power using the overheated steam can be improved.

  A plurality of the superheated steam supply paths may be connected to the drying chamber, and the steam flow rates of any of the superheated steam supply paths may be different.

  In this way, by connecting a plurality of superheated steam supply paths with different steam flow rates to the drying chamber and supplying superheated steam from each superheated steam supply path to the drying chamber, the fluid medium and wet biomass are superheated in the drying chamber. It can move from a high steam flow position to a low position. Thereby, wet biomass and superheated steam can be mixed well, and drying of wet biomass can be accelerated.

  The steam flow rates of the plurality of superheated steam supply paths may be set such that the wet biomass and the fluid medium circulate in the drying chamber.

  Thus, by circulating the wet biomass and the fluid medium to form a circulating flow, the drying of the wet biomass can be further accelerated.

  The superheated steam supply path is a first superheated steam supply path, is connected to a side wall of the drying chamber, and moves the fluid medium and the dried biomass from the drying chamber toward the combustion chamber with respect to the fluidized bed A second superheated steam supply path for supplying superheated steam into the drying chamber may be further provided.

  According to the above configuration, the wet biomass can be brought into contact with the superheated steam from a plurality of positions on the lower side and the side of the drying chamber to accelerate the drying of the wet biomass. Moreover, the dry biomass in the incinerator can be efficiently transported.

  The power generating apparatus is a binary power generating apparatus including: a heat exchanger in which the overheated steam flowing through the overheated vapor discharge path exchanges heat with a heat medium; and a generator connected to the heat exchanger and generating electricity from the heat medium It may be

  Thereby, in the heat exchanger, the heat medium and the superheated steam are subjected to heat exchange, and the heat medium drives the power generation device, whereby the power generation device can efficiently generate power.

  A detour that branches to bypass the power generation device from the superheated steam discharge channel, and a branch from the upstream side of the position where the power generation device of the superheated steam discharge channel is provided, and flows through the superheated steam discharge channel The fuel cell system further includes a branch path including one of an open path for opening the superheated steam to the atmosphere, and the branch path is provided with a valve for making the amount of the superheated steam supplied to the power generation apparatus constant. It is also good.

  According to the above configuration, the amount of overheated steam flowing through the power generation device can be made constant, and stable power generation can be obtained in the power generation device.

  A superheated steam recirculation path connected between the superheated steam supply path and the superheated steam discharge path and returning a part of the superheated steam flowing through the superheated steam discharge path to the superheated steam supply path may be further provided. .

  Thereby, even if the amount of superheated steam in the drying chamber is insufficient, for example, the superheated steam can be supplied from the superheated steam return path into the drying chamber, and the shortage can be compensated.

  A dust collector provided in the middle of the superheated steam discharge path and connected between a dust collector for collecting dust contained in the superheated steam, the dust collector and the incinerator, and returning the dust collected by the dust collector to the combustion chamber And a path may be further provided.

  As a result, it is possible to concentrate the dried biomass combustion ash and dust in one place, and to easily manage the combustion ash and dust.

  The superheated steam flow passage is further branched from the superheated steam supply passage and connected to the drying chamber, and the superheated steam flowing through the superheated steam flow passage drops toward the fluidized bed in the drying chamber. It may be jetted while being dispersed to the wet biomass.

  Thereby, the wet biomass can be accelerated by dispersing the wet biomass with the superheated steam flowing through the branch path and efficiently contacting the wet biomass with the superheated steam.

  The system may further include a wet biomass feed path connected to the incinerator and supplying the wet biomass to the drying chamber, and the wet biomass feed path may be provided via the combustion chamber.

  Thus, the wet biomass can be preheated before being supplied to the drying chamber, and the drying of the wet biomass in the drying chamber can be accelerated.

  According to each aspect of the present invention described above, it is possible to provide a wet biomass incineration system that can be operated at low running cost and good combustion efficiency and can reduce facility cost by suppressing the loss of heat recovery of the power generation apparatus.

It is a figure showing the whole wet biomass incineration system concerning a 1st embodiment. It is a figure which shows a part of wet biomass incineration system which concerns on 2nd Embodiment. It is a figure showing a part of wet biomass incineration system concerning a 3rd embodiment. It is a figure which shows a part of wet biomass incineration system which concerns on 4th Embodiment. It is a figure which shows a part of wet biomass incineration system concerning 5th Embodiment. It is a figure which shows a part of wet biomass incineration system concerning 6th Embodiment. It is a figure which shows a part of wet biomass incineration system which concerns on 7th Embodiment. It is a figure showing a part of wet biomass burning system concerning an 8th embodiment. It is a figure which shows a part of wet biomass incineration system which concerns on 9th Embodiment. It is a figure which shows a part of wet biomass incineration system which concerns on 10th Embodiment.

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

First Embodiment
FIG. 1 is a diagram showing the entire wet biomass incineration system 1 according to the first embodiment. As shown in FIG. 1, the wet biomass incineration system 1 includes an incinerator 2, a dust collector 3, a power generation device 4, a wet biomass supply path R1, a superheated steam supply path R2, a superheated steam discharge path R3, an oxidizing gas supply path R4, A combustion gas discharge path R5 and a combustion ash discharge path R6 are provided.

  In the incinerator 2, the space S1 and S2 above the hearth 2i are partitioned by the partition wall 2e, so that the drying chamber 2a for drying the wet biomass M and the dry biomass (dried wet biomass M) are combusted. A combustion chamber 2b is formed. Further, the incinerator 2 is provided with fluidized beds 2c and 2d over the lower part in the drying chamber 2a and the lower part in the combustion chamber 2b. The fluidized beds 2 c and 2 d are configured using a fluid medium F. The fluid medium F is, for example, silica sand, but the fluid medium F is not limited thereto.

  A wet biomass feed port 2a1 is formed above the drying chamber 2a. A wet biomass supply passage R1 for supplying the wet biomass M from the outside into the drying chamber 2a is connected to the wet biomass supply port 2a1. Below the fluidized bed 2c of the drying chamber 2a, an air box 2f that is a hollow box is provided. Below the air box 2f is connected a superheated steam supply passage R2 for supplying superheated steam for drying the wet biomass M while mixing it with the fluid medium (particulate matter) F to the drying chamber 2a. Above the drying chamber 2a, a superheated steam discharge passage R3 for discharging the superheated steam used for drying the wet biomass M to the outside of the drying chamber 2a as exhaust gas is connected.

  Below the fluidized bed 2d of the combustion chamber 2b, a wind box 2g having a configuration similar to that of the wind box 2f is provided. Below the air box 2g, an oxidizing gas supply passage R4 is connected which supplies an oxidizing gas for burning the dry biomass while mixing it with the fluid medium F to the combustion chamber 2b. The air box 2f, 2g is partitioned by a partition wall 2h. Above the combustion chamber 2b, a combustion gas discharge passage R5 for discharging the combustion gas generated by the combustion of the dry biomass to the outside of the combustion chamber 2b is connected.

  A plurality of nozzles 2j are provided in a distributed manner in the hearth 2i disposed below the fluidized beds 2c and 2d. The superheated steam supplied from the superheated steam supply passage R2 is ejected from the nozzles 2j in the drying chamber 2a into the drying chamber 2a via the air box 2f. In the fluidized bed 2c, the wet biomass M flows together with the fluid medium F by the flow of the superheated steam spouted from the respective nozzles 2j, and is dried while being stirred and mixed to become a dried biomass. As shown in FIG. 1, dry biomass is sent from the drying chamber 2a to the combustion chamber 2b. The oxidizing gas supplied from the oxidizing gas supply passage R4 is ejected from the nozzles 2j in the combustion chamber 2b into the combustion chamber 2b via the air box 2g. The oxidizing gas is, for example, air, but is not limited thereto. In the fluidized bed 2d, the dried biomass flows together with the fluid medium F by the flow of the oxidizing gas ejected from each nozzle 2j, and is burned while being stirred and mixed. The heat of the combustion chamber 2b moves to the drying chamber 2a side together with the fluid medium F, and is used for drying the wet biomass M in the drying chamber 2a.

  A combustion ash discharge path R6 for discharging the combustion ash of dry biomass is connected to the combustion chamber 2b. The combustion ash (incineration ash) generated along with the combustion of the dry biomass is discharged out of the combustion chamber 2b via the combustion ash discharge passage R6.

  The dust collector 3 is provided in the superheated steam discharge passage R3. The dust collector 3 collects the dust mixed in the superheated steam flowing through the superheated steam discharge path R3.

  The power generation device 4 is, for example, a binary power generation device, and includes an evaporator 5, a preheater 6, a turbine generator 7, a condenser 8, a cooling tower 9, and a plurality of pumps P1 to P3. In the power generation device 4, the superheated steam flowing in the superheated steam discharge passage R3 is sent to the evaporator 5 by the pump P1 and is heat-exchanged with the low boiling heat medium flowing in the heat medium circulation passage R7. Thereafter, the superheated steam is sent to the preheater 6 for further heat exchange and released to the outside. In the evaporator 5, the low boiling point heat medium is heat exchanged with the superheated steam and vaporized. The vaporized low-boiling point heat medium is sent to the turbine generator 7 to be used for power generation. The low boiling heat medium is then sent to the condenser 8. The low boiling point heat medium is cooled in the cooling tower 9 and heat-exchanged with the cooling water flowing through the flow path R8 by the pump P3 to be condensed. As a result, the low boiling point heat medium is liquefied, sent to the preheater 6 by the pump P2, and preheated. Thereafter, the low boiling heat medium is sent to the evaporator 5 again.

  In the wet biomass incineration system 1, the wet biomass M is dried with superheated steam supplied to the drying chamber 2a. By conveying the dried biomass produced thereby to the combustion chamber 2b together with the fluid medium F, the dried biomass is easily ignited in the combustion chamber 2b, and the combustion efficiency is enhanced. Moreover, the temperature of the superheated steam supplied to the drying chamber 2a is set so that the temperature of the fluidized bed 2c becomes lower than the thermal decomposition temperature of the dry biomass. Although the temperature of this superheated steam can be set suitably, it can set to the range from which the temperature of the fluidized bed 2c becomes 100 to 150 degreeC, for example. In addition, the temperature of “below pyrolysis” as used herein is not limited to a strict temperature at which dry biomass in the drying chamber 2a is not pyrolyzed at all, and a temperature that allows some pyrolysis (the superheated steam discharge path R3 It can be set to a temperature at which the concentration of components other than water vapor in the circulating gas is several percent or less. Thus, by setting the temperature of the fluidized bed 2c to less than the thermal decomposition temperature of the dry biomass, thermal decomposition of the dry biomass in the drying chamber 2a is prevented, and the gas generated along with the thermal decomposition of the dry biomass is Mixing into the superheated steam flowing through the superheated steam discharge path R3 from the drying chamber 2a is prevented. In the incinerator 2, since the space S1 of the drying chamber 2a and the space S2 of the combustion chamber 2b are partitioned by the partition wall 2e, the combustion chamber is transferred from the drying chamber 2a to the superheated steam flowing through the superheated steam discharge path R3. It is suppressed that the combustion gas in 2b mixes. Therefore, the superheated steam of high purity can be supplied to the power generation device 4. As described above, since the superheated steam of high purity is supplied to the power generation device 4, the heat recovery of the power generation device 4 can be performed using almost all of the gas flowing through the superheated steam discharge passage R3. Thus, as in Patent Document 1, for example, the step of purifying the gas by removing in advance the impurity components (components other than the superheated steam) of the gas supplied to the power generation device 4 using a condenser or a scrubber is unnecessary. is there. Therefore, the wet biomass incineration system 1 can stably generate electric power with high power generation efficiency by effectively using the latent heat rich in superheated steam while suppressing the loss of heat recovery.

  In general, in a kiln-type dryer, in order to dry the wet biomass within a predetermined time, it is necessary to set a drying gas for drying the wet biomass to a considerably high temperature. In contrast, in the wet biomass incineration system 1 including the internal circulation fluidized bed type incinerator 2, the wet biomass M is mixed with the fluid medium F to increase the contact efficiency of the wet biomass M and superheated steam. It can dry efficiently. Therefore, even if the temperature of the superheated steam supplied to the drying chamber 2a is set below the thermal decomposition temperature of the dry biomass, the wet biomass M can be dried quickly and satisfactorily.

  Also, in the wet biomass incineration system 1, the superheated steam after drying the wet biomass M is discharged to the superheated steam discharge passage R3, and used for power generation of the power generation device 4, utilizing the latent heat of abundant superheated steam, It can generate power with high power generation efficiency. In addition, since the gas generated due to the thermal decomposition of dry biomass is not used for power generation, the power generation device 4 or the exhaust gas flow passage (superheated steam discharge passage R3) is prevented from being contaminated by the gas, and the power generation efficiency is not lowered. . Therefore, in the wet biomass incineration system 1, the incinerator 2 can be operated with good combustion efficiency, and the running cost can be reduced.

  Further, by integrally forming the incinerator 2 so as to have the drying chamber 2a and the combustion chamber 2b, the incinerator 2 can be configured compactly, and the equipment cost of the wet biomass incineration system 1 can be suppressed.

  In the wet biomass incineration system 1 according to the first embodiment, the pump P1 and the preheater 6 can be omitted.

  Hereinafter, each other embodiment of the present invention will be described focusing on differences from the first embodiment.

Second Embodiment
FIG. 2 is a view showing a part of the wet biomass incineration system 1 according to the second embodiment. As shown in FIG. 2, the wet biomass incineration system 1 is connected to an incinerator 2, a wet biomass supply path R <b> 1 as a first wet biomass supply path that supplies wet biomass M directly into the drying chamber 2 a, and overheating. A second wet biomass supply path R1a connected to the steam discharge path R3 and supplying the wet biomass M into the drying chamber 2a via a part of the superheated steam discharge path R3 is further provided. The incinerator 2 has a plurality of wet biomass feed ports 2a1 provided apart from each other. The first wet biomass supply path R1 and the second wet biomass supply path R1a are individually connected to the wet biomass supply port 2a1. Thereby, in the incinerator 2, the wet biomass M is supplied into the drying chamber 2a from a plurality of positions.

  Thus, for example, the drying chamber 2a can be provided by dispersing and supplying the wet biomass M from the plurality of positions into the drying chamber 2a through the first wet biomass supply passage R1 and the second wet biomass supply passage R1a. Even when transporting the wet biomass M, the wet biomass M can be efficiently and rapidly dried with superheated steam to produce dry biomass. In addition, it is possible to prevent the deposition of the wet biomass M locally in the drying chamber 2a and an increase in the load on the hearth 2i. A screw conveyor or a mono pump is disposed in any of the first wet biomass supply passage R1 and the second wet biomass supply passage R1a for the purpose of promoting the supply of the wet biomass M into the drying chamber 2a. You may

  The second wet biomass feed passage R1a may be directly connected to the wet biomass feed port 2a1 without being connected to the superheated steam discharge passage R3.

Third Embodiment
FIG. 3 is a diagram showing a part of the wet biomass incineration system 1 according to the third embodiment. As shown in FIG. 3, the incinerator 2 has a height lower than the bed height of the fluidized bed 2d from the bottom of the fluidized bed 2d (furnace floor 2i) inside the fluidized bed 2d on the combustion chamber 2b side in the vicinity of the drying chamber 2a. It further has a partition wall 2k provided so as to extend. As an example, the plate surface of the partition wall 2k is disposed to face the plate surface of the partition wall 2e at a distance. The partition wall 2e is provided at a position closer to the drying chamber 2a than the partition wall 2k. As a result, in the center of the interior of the incinerator 2, an intermediate area A sandwiched between the partition wall 2e and the partition wall 2k is formed.

  By using such a partition wall 2k, it is possible to further prevent the combustion gas or the oxidizing gas in the combustion chamber 2b from flowing into the drying chamber 2a and the combustion gas or the oxidizing gas from being mixed in the overheated vapor. Therefore, since the power generation device 4 can generate power using the latent heat rich in superheated steam, the power generation efficiency of the power generation device 4 can be improved. In the third embodiment, the air pressure in the drying chamber 2a is made higher than the air pressure in the combustion chamber 2b, and a part of the superheated steam in the drying chamber 2a is made through the intermediate area A of the partition wall 2k and the partition wall 2e. By inflowing into the combustion chamber 2b, it is possible to further prevent the combustion gas or the oxidizing gas from being mixed in the overheated vapor in the drying chamber 2a.

Fourth Embodiment
FIG. 4 is a diagram showing a part of the wet biomass incineration system 1 according to the fourth embodiment. As shown in FIG. 4, the incinerator 2 has divided chambers 2 f 1, 2 f 2 and 2 f 3 in which the air box 2 f is divided into a plurality. The superheated steam supply path R2 has a plurality of superheated steam supply branch paths (hereinafter simply referred to as “branch paths”) R2a, R2b, and R2c. Branch paths R2a, R2b, R2c are sequentially connected to the division chambers 2f1, 2f2, 2f3. Valves V1, V2, and V3 are provided in order in the branch paths R2a, R2b, and R2c. By adjusting the valves V1, V2, and V3, the steam flow rates in the branch paths R2a, R2b, and R2c are set to be different from each other.

  As described above, by connecting the branch paths R2a, R2b and R2c set so that the flow rates of the vapor are different from each other to the drying chamber 2a via the division chambers 2f1 to 2f3, the fluid medium F and the flow medium F can be The wet biomass M can be circulated and moved among the branch paths R2a, R2b, and R2c from a position where the steam flow rate is high to a position where the steam flow rate is low. Thereby, wet biomass M and superheated steam can be mixed well, and drying of wet biomass M can be accelerated. Here, for example, if the valves V1, V2, and V3 are adjusted so that the steam flow rate decreases as the distance from the combustion chamber 2b increases, the wet biomass M that circulates in the depth direction of the fluidized bed 2c in the drying chamber 2a. In addition, a circulation flow of the fluid medium F is formed, and it is considered that the drying of the wet biomass M can be further accelerated.

Fifth Embodiment
FIG. 5 is a view showing a part of the wet biomass incineration system 1 according to the fifth embodiment. As shown in FIG. 5, the superheated steam supply passage R2 is connected to the drying chamber 2a as a first superheated steam supply passage. The wet biomass incineration system 1 further includes a second superheated steam supply passage R9 connected to the side wall of the drying chamber 2a of the incinerator 2. The second superheated steam supply path R9 supplies superheated steam into the drying chamber 2a so as to promote the movement of the fluid medium F and the dry biomass from the drying chamber 2a toward the combustion chamber 2b.

  By supplying superheated steam into the drying chamber 2a from both the first superheated steam supply passage R2 and the second superheated steam supply passage R9, wet biomass can be obtained from a plurality of positions below and on the side of the drying chamber 2a. M can be brought into contact with superheated steam, and drying of wet biomass M can be accelerated. In addition, the superheated steam supplied from the second superheated steam supply path R9 facilitates the movement of the fluidized medium F and the dry biomass from the drying chamber 2a to the combustion chamber 2b, so that the dry biomass is efficiently obtained in the incinerator 2. It can be transported.

Sixth Embodiment
FIG. 6 is a diagram showing a part of the wet biomass incineration system 1 according to the sixth embodiment. As shown in FIG. 6, the wet biomass incineration system 1 branches from the superheated steam discharge path R3 upstream of the position where the power generation device 4 is provided as a branch path of the superheated steam discharge path R3, and the superheated steam is discharged. An open path R10 that opens to the atmosphere, and a bypass R11 that branches from the superheated steam discharge path R3 so as to bypass the power generation device 4 are further provided. The open passage R10 is provided with a valve V4, and the bypass passage R11 is provided with a valve V5. The valves V4 and V5 are provided to keep the amount of superheated steam supplied to the power generation device 4 at or below a predetermined constant value. When the amount of superheated steam in the superheated steam discharge path R3 exceeds the predetermined value, at least one of the valves V4 and V5 is operated to release a part of the superheated steam to the outside, whereby the amount of superheated steam sent to the power generation device 4 Is made constant.

  Thus, by adjusting the amount of overheated steam to be circulated to the power generation device 4 to be constant, for example, as shown in FIG. 1, the power generation device 4 generates power using a heat medium different from the overheated steam. Even in the case of a binary power generation device or the like, the response delay can be alleviated and stable generated power can be obtained.

  It is not necessary to provide both the open passage R10 and the valve V4, and the detour R11 and the valve V5, and only one of them may be provided.

Seventh Embodiment
FIG. 7 is a diagram showing a part of the wet biomass incineration system 1 according to the seventh embodiment. As shown in FIG. 7, the wet biomass incineration system 1 is connected between the superheated steam supply path R2 and the superheated steam discharge path R3, and a part of the superheated steam flowing through the superheated steam discharge path R3 is superheated steam supply path. A superheated steam recirculation path R12 for returning to R2 is further provided. For example, a pump P4 for returning the superheated steam to the superheated steam supply path R2 is provided in the superheated steam return path R12.

  By using the superheated steam recirculation path R12 and the pump P4, for example, even when the superheated steam supply amount in the drying chamber 2a is insufficient, the superheated steam is supplied into the drying chamber 2a via the superheated steam recirculation path R12. It is possible to reflux and make up for the shortage of superheated steam.

Eighth Embodiment
FIG. 8 is a diagram showing a part of the wet biomass incineration system 1 according to the eighth embodiment. As shown in FIG. 8, the wet biomass incineration system 1 further includes a soot dust passage R <b> 13 connected between the dust collector 3 and the incinerator 2. The dust flow passage R13 is used to supply the dust collected by the dust collector 3 to the combustion chamber 2b. By using the dust flow passage R13, the dust and the combustion ash of the dry biomass generated in the combustion chamber 2b can be collected in one place (in the combustion chamber 2b). Therefore, for example, it is possible to facilitate management of post-processing of soot and combustion ash.

The ninth embodiment
FIG. 9 is a view showing a part of the wet biomass incineration system 1 according to the ninth embodiment. The wet biomass incineration system 1 further includes a superheated steam flow path R14 branched from the superheated steam supply path R2 and connected to the drying chamber 2a. A nozzle (not shown) having a plurality of nozzle openings is attached to the tip of the overheated steam flow passage R14 on the drying chamber 2a side. The superheated steam that has flowed through the superheated steam flow passage R14 is ejected while being dispersed to the wet biomass M that falls toward the fluidized bed 2c in the drying chamber 2a. As a result, the superheated steam is abundantly supplied into the drying chamber 2a, and the wet biomass M is dispersed and supplied. Therefore, it is possible to prevent the damp drying of the wet biomass M, and it is possible to accelerate the drying by efficiently contacting the wet biomass M and the superheated steam. In addition, local deposition of the wet biomass M in the drying chamber 2a is suppressed, and an increase in load on the hearth 2i can be prevented.

Tenth Embodiment
FIG. 10 is a view showing a part of the wet biomass incineration system 1 according to the tenth embodiment. The wet biomass supply path R1 connected to the incinerator 2 is provided so that the combustion gas in the combustion chamber 2b and the wet biomass M pass through the combustion chamber 2b so that heat exchange is possible. Thus, by arranging the wet biomass supply path R1, the wet biomass M can be preheated before being supplied to the drying chamber 2a, and the drying of the wet biomass M in the drying chamber 2a can be accelerated. Therefore, it is possible to prevent a shortage of superheated steam supplied into the drying chamber 2a. Moreover, since the amount of exhaust superheated steam can be increased because the wet biomass M can be sufficiently dried in the drying chamber 2a, abundant superheated steam can be supplied to the power generation device 4 and improvement in power generation efficiency can be expected.

  The present invention is not limited to the embodiments described above, and the configuration can be changed, added, or deleted without departing from the spirit of the present invention. The above embodiments may be arbitrarily combined with each other. For example, a part of the configuration in one embodiment may be applied to another embodiment.

  The wet biomass incineration system 1 includes a concentration measuring device for water vapor flowing through the superheated steam discharge passage R3, a pressurizing device (for example, a fan or blower) for pressurizing the gas flowing through the superheated steam discharge passage R3, and the concentration measurement And a controller connected to the pressure device. As a result, when the concentration of water vapor in the gas flowing through the superheated steam discharge passage R3 falls below a certain level, the control unit operates the pressurizing device to cause water vapor in the gas flowing through the superheated steam discharge passage R3. It is also possible to increase the partial pressure so that the power generation device 4 can stably generate power.

F Flowing medium M Wet biomass R1 Wet biomass feed path (first wet biomass feed path)
R1a second wet biomass feed line R2 superheated steam supply line (first superheated steam supply line)
R2a, R2b, R2c Superheated steam supply branch R3 Superheated steam discharge R4 Oxidizing gas supply R9 Second superheated steam supply R10 Open R12 Superheated steam return R13 Dust dust flow R14 Superheated steam flow S1 Space of drying chamber S2 Combustion chamber space V4, V5 Low pressure valve 2 Incinerator 2a Drying chamber 2a1 Wet biomass supply port 2b Combustion chamber 2c, 2d Fluidized bed 2e Partition wall 2k Partition wall 3 Dust collector 4 Power generator 5 Evaporator (heat exchanger)
6 Preheater (heat exchanger)
7 Generator

Claims (12)

An incineration having a drying chamber and a combustion chamber in which the space above the hearth is partitioned by a partition wall, and provided with a fluidized bed in which a fluid medium flows over the lower portion of the drying chamber and the lower portion of the combustion chamber. A furnace,
A power generation device that generates power using the exhaust gas of the incinerator;
A superheated steam supply path connected to the lower side of the fluidized bed on the drying chamber side and supplying superheated steam for drying while mixing wet biomass with the fluidized medium in the drying chamber;
An oxidizing gas connected to the lower side of the fluidized bed on the combustion chamber side for burning the dried biomass produced by drying the wet biomass while mixing with the fluidized medium in the combustion chamber is supplied into the combustion chamber. An oxidizing gas supply channel,
A superheated steam discharge passage connected to the drying chamber and discharging the superheated steam used for drying the wet biomass to the outside of the drying chamber,
The temperature of the fluidized bed in the drying chamber is set to be lower than the thermal decomposition temperature of the dry biomass, and the exhaust gas becomes superheated steam that circulates in the superheated steam discharge path, and the power generation device generates heat of the dry biomass. A wet biomass incineration system , which generates power by the superheated steam without using a gas generated by decomposition . An incinerator having a drying chamber and a combustion chamber in which a space above the hearth is divided by partition walls, and a fluidizing medium flowing between the lower inside of the drying chamber and the lower inside of the combustion chamber. A furnace,
A power generation device that generates power using exhaust gas of the incinerator;
A superheated steam supply path connected below the fluidized bed on the drying chamber side and supplying superheated steam into the drying chamber for drying while mixing wet biomass with the fluid medium in the drying chamber;
It is connected to the lower part of the fluidized bed on the combustion chamber side, and supplies an oxidizing gas into the combustion chamber for burning the dry biomass generated by drying the wet biomass while mixing it with the fluid medium in the combustion chamber. The oxidizing gas supply
A superheated steam discharge path which is connected to the drying chamber and discharges the superheated steam used for drying the wet biomass out of the drying chamber and sends it to the power generation apparatus;
A first wet biomass supply path connected to the incinerator and supplying the wet biomass directly into the drying chamber;
A second wet biomass supply passage connected to the superheated steam discharge passage and supplying the wet biomass into the drying chamber via a part of the superheated steam discharge passage;
The wet biomass incineration system, wherein the temperature of the fluidized bed in the drying chamber is set to less than the thermal decomposition temperature of the dry biomass, and the exhaust gas is superheated steam flowing through the superheated steam discharge channel.   The incinerator extends from the lower side of the fluidized bed on the combustion chamber side to a height lower than the bed height of the fluidized bed in the combustion chamber, inside the fluidized bed on the combustion chamber side near the drying chamber. The wet biomass incineration system according to claim 1 or 2, further comprising a partition wall provided in.   The wet biomass incineration system according to any one of claims 1 to 3, wherein a plurality of the superheated steam supply paths are connected to the drying chamber, and a steam flow rate of any of the superheated steam supply paths is different.   The wet biomass incineration system according to claim 4, wherein steam flow rates of the plurality of superheated steam supply paths are set such that the wet biomass and the fluid medium circulate in the drying chamber. The superheated steam supply path is a first superheated steam supply path,
A second superheater connected to a side wall of the drying chamber and supplying superheated steam into the drying chamber so as to promote movement of the fluid medium and the dried biomass from the drying chamber toward the combustion chamber. The wet biomass incineration system according to any one of claims 1 to 5, further comprising a steam supply channel.   The power generating apparatus is a binary power generating apparatus including: a heat exchanger in which the overheated steam flowing through the overheated vapor discharge path exchanges heat with a heat medium; and a generator connected to the heat exchanger and generating electricity from the heat medium The wet biomass incineration system according to any one of claims 1 to 6, which is A detour that branches to bypass the power generation device from the superheated steam discharge channel, and a branch from the upstream side of the position where the power generation device of the superheated steam discharge channel is provided, and flows through the superheated steam discharge channel Further comprising a branch path including one of an open path for opening the overheated steam to the atmosphere,
The wet biomass incineration system according to claim 7, wherein a valve for making the amount of superheated steam supplied to the power generation device constant is provided in the branch path.   The superheated steam recirculation path which is connected between the superheated steam supply path and the superheated steam discharge path, and returns a part of the superheated steam flowing through the superheated steam discharge path to the superheated steam supply path. The wet biomass incineration system according to any one of -8. A dust collector provided in the middle of the superheated steam discharge path for collecting soot contained in the superheated steam,
The wet biomass incineration according to any one of claims 1 to 9, further comprising: a dust flow passage connected between the dust collector and the incinerator and returning the dust collected by the dust collector to the combustion chamber. system. It further comprises a superheated steam flow passage branched from the superheated steam supply passage and connected to the drying chamber,
The superheated steam which distribute | circulated the said superheated steam flow channel | path is spouted in the said drying chamber, disperse | distributing with respect to the said wet biomass falling toward the said fluidized bed. Wet biomass incineration system. It further comprises a wet biomass supply path connected to the incinerator and supplying the wet biomass to the drying chamber,
The wet biomass incineration system according to any one of claims 1 to 11, wherein the wet biomass supply path is provided via the combustion chamber.

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