JP3740081B2 - Fluidized bed incinerator equipped with fluidized medium deposit removal method and fluidized media deposit removal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fluidized bed incinerator for burning waste, RDF, coal, or the like, and a method for removing deposits of a fluidized medium outside the furnace, and a fluidized bed incinerator equipped with a removing device used in this method. Is.
[0002]
[Prior art]
In the fluidized bed incinerator, a part of the ash adheres or covers the surface of the fluidized medium (mainly dredged sand) during operation, and the particle size tends to increase as compared with the initial charging. Since the enlarged particles have a higher fluidization start speed, it is necessary to increase the amount of ventilation in order to maintain an appropriate flow state, which increases the utility of the ventilation system. Moreover, since the amount of exhaust gas increases when the amount of ventilation increases, the utility of the exhaust gas treatment system increases.
[0003]
As a conventional technique relating to a method for regenerating a fluid medium, for example, in Japanese Patent Application Laid-Open No. Sho 56-160513, water is infiltrated into ash adhering to a fluid medium of a heavy oil-fired boiler, and moisture containing ash is adhered. Describes a technique for returning a fluidized medium to a fluidized bed furnace. However, in this method, the fluid medium extracted during operation is at a high temperature, and water is permeated into the fluid medium at the high temperature, which may cause the fluid medium itself to be crushed by thermal shock. In addition, since the adhered substance is returned to the furnace, there is a possibility that the substance causing the adhesion is concentrated in the furnace.
[0004]
Japanese Patent No. 3020464 discloses a sand cleaning apparatus equipped with a screw conveyor. This technique uses washing water and requires a device for treating waste water. Moreover, since there is an operating part in the apparatus, the operating member may be damaged due to abrasion with sand.
[0005]
Japanese Patent Application Laid-Open No. 8-504131 discloses a technique relating to a method for regenerating foundry sand, particularly sand containing active bentonite. In this technique, compressed air is blown into the bed to form a fluidized bed, which enables recovery of valuable materials contained in the sand. This technology is not a deposit removal technology for fluid media in a fluidized bed furnace in which a fuel containing Ca and / or Mg content or a Ca compound and / or Mg compound is added and burned, but the recovered deposits are desalted. It is not a technology used as a drug such as a drug.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above points, and an object of the present invention is to once extract a fluid medium enlarged with deposits in a fluidized bed incinerator and then blow high-speed air into the fluid medium. By removing substances adhering to the fluidized medium, regenerating the fluidized medium and optimizing the particle size, it becomes easy to maintain an appropriate fluidized state in the fluidized bed incinerator, and the ventilation system and exhaust gas treatment It is an object of the present invention to provide a fluidized bed incinerator having a fluidized medium deposit removing method that does not increase the utility of the system, and a removing device used in this method.
[0007]
Another object of the present invention is to blow high-speed air into the fluid medium drawn out of the furnace to remove substances adhering to the fluid medium, so that the fluid medium itself has a rapid temperature even when the fluid medium is withdrawn during operation. Fluidized medium deposits that are not subject to thermal shock due to changes, do not concentrate the causative substances in the furnace, and have a very simple removal device configuration and less wear damage to the device due to fluidized media It is an object to provide a fluidized bed incinerator equipped with a removal method and a removal device used in this method.
Another object of the present invention is to use the collected adhering powder as a chemical in a fluidized bed incinerator in which a fuel containing Ca and / or Mg or a Ca compound and / or Mg compound is added and burned. It is to provide a technology that can be used effectively.
[0008]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the fluid medium deposit removal method of the present invention extracts a fluid medium enlarged by deposits from a fluidized bed incinerator and removes the fluid medium extracted outside the furnace from the deposit. The substance adhering to the fluidized medium is removed by blowing high-speed air into the device, and the fluidized medium is regenerated and the particle size is optimized, and the removed deposits are collected by the dust collector. Is configured to do.
[0009]
In addition, the method of the present invention is a method in which a fuel containing Ca and / or Mg is added or fluid is enlarged by deposits from a fluidized bed incinerator where a Ca compound and / or Mg compound is added and burned. The medium is extracted, the fluid medium extracted outside the furnace is put into a deposit removing device, and the substance adhering to the fluid medium is removed by blowing high-speed air into the device. It is characterized by optimizing, collecting the removed deposits with a dust collector, and using the collected deposits as chemicals such as a desalting agent, a desulfurizing agent, and an adsorbent.
In these methods, the air after dust removal discharged from the dust collector can be used as primary air and / or secondary air in a fluidized bed incinerator.
[0010]
In the case where the fluidized bed incinerator is a circulating fluidized bed furnace, the fluid medium enlarged by the deposits is extracted from the fluidized bed for heat recovery in the circulating fluidized bed furnace and is put into the deposit removing apparatus.
[0011]
The fluidized bed incinerator equipped with the fluidized medium deposit removal device of the present invention is a fluidized bed incinerator that burns fuel such as waste, RDF (garbage solidified fuel) or coal, and is enlarged by deposits. The fluid medium extraction means for extracting the fluid medium that has been removed from the fluidized bed incinerator and the fluid medium extracted outside the furnace are stored, and high-speed air is blown into the fluid medium group to remove substances adhering to the fluid medium. Adherent removal device, dust collector for collecting the removed adhering matter installed at the latter stage of the adhering matter removal device, and fluid medium that has been optimized for particle size by removing the adhering matter It is characterized by including a fluidized bed incinerator or / and a fluidized medium circulation system that returns to a BM (fluidized medium) storage tank.
[0012]
Moreover, the fluidized bed incinerator equipped with the fluidized medium deposit removal device of the present invention is combusted by adding fuel containing Ca and / or Mg or adding Ca compound and / or Mg compound. Fluidized bed incinerator, fluidized medium extracting means for extracting the fluidized medium enlarged by deposits from the fluidized bed incinerator, and storing the fluidized medium extracted outside the furnace, and storing high-speed air in the fluidized media group. A deposit removing device that removes substances adhering to the fluid medium by blowing, a dust collector for collecting the removed deposit installed downstream of the deposit removing device, and a powder of collected deposit As a substitute for desalting agent and adsorbent, the recovered deposit blowing means that blows into the exhaust gas treatment system of the incinerator and the fluidized medium that has been optimized for particle size by removing the deposit are extracted from the deposit removing device. Fluidized bed incinerator or And BM is characterized by comprising encompass the fluidized medium circulation line back to the (fluidized medium) reservoir.
[0013]
When the fluidized bed incinerator is a circulating fluidized bed furnace, a fluidized medium extraction means is provided in the fluidized bed for heat recovery in the circulating fluidized bed furnace, and the fluidized medium enlarged by the adhered material is used as the adhered material removing device. throw into.
[0014]
In these cases, the deposit removing device may be configured to blow air from the lower part of the fluidized medium group using an air diffuser, or may be configured to blow air from the lower side of the fluidized medium group using a nozzle on a dispersion plate.
Moreover, the case where a BM (fluid medium) storage tank is used as the deposit removal apparatus main body and the deposit removal apparatus main body may be installed separately from the BM storage tank.
The BM outlet of the deposit removing device is not limited to the bottom of the device, but may be provided on the side surface of the device.
Moreover, the air supply system for utilizing the air after dust removal discharged | emitted from a dust collector as primary air and / or secondary air of a fluidized bed incinerator can be provided.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications. FIG. 1 shows an example of a fluidized bed incinerator equipped with a fluid medium deposit removing device according to a first embodiment of the present invention. In this embodiment, as an example, in a fluidized bed incinerator that burns a fuel containing Ca (such as RDF) or burns waste, RDF, coal, or the like by adding a Ca compound, It removes the adhered substances.
[0016]
In the fluidized bed incinerator 10, a part of the ash melts and adheres to or covers the surface of the fluidized medium (mainly dredged sand) during operation, and the particle size increases compared to the initial charging time. Therefore, the enlarged fluidized medium (BM) is extracted from the fluidized bed incinerator 10 and the deposits are removed outside the furnace. The BM extracted from the lower part of the fluidized bed incinerator 10 together with incombustibles and the like is separated into the incombustibles with a sieve or the like (not shown), and then introduced into the deposit removing device 12. In addition, although the illustration is omitted, when the fluidized bed incinerator is a circulating fluidized bed furnace, the fluidized medium is extracted from the fluidized bed for heat recovery in the circulating fluidized bed furnace, and the adhering substance removing device is removed. Just put it in. In the present embodiment, the deposit removal device 12 is installed separately from the BM storage tank 14. High-speed air is blown into the fluid medium group in the deposit removal device 12, the deposits are removed by the wear action of the fluid media, and the fluid medium is regenerated and the particle diameter is optimized. In this case, the blown air flow velocity is, for example, 100 m / s or more. 16 is a blower.
[0017]
As shown in FIGS. 1 and 2, the deposit removing device 12 can be configured to blow air from the lower side of the fluid medium group through the nozzles 20 on the dispersion plate 18. The nozzle 20 can be configured as shown in FIG. 2, for example. In this case, as an example, as shown in FIGS. 3, 4, and 5, the air blowing direction may be directed substantially in the center direction or from the outside to the inside with the dispersion plate 18 provided with the nozzle viewed from above. The air can be blown. 3, 4, and 5, the starting point of the arrow is the blowing portion (nozzle). In addition, the deposit removing device 12 may be configured to blow air from the lower part of the fluid medium group through an air diffuser.
[0018]
The treated BM having an optimized particle diameter is extracted from the BM outlet 22 of the deposit removing device 12 and returned to the fluidized bed incinerator 10 through the BM circulation line 24. In this case, the treated BM can be returned to the BM storage tank 14. The BM outlet of the deposit removing device 12 is not limited to the bottom of the device, but may be provided on the side surface of the device. Further, the removed deposits are collected by a dust collecting device 26 installed at the rear stage of the deposit removing device 12. As an example of the dust collector 26, a filtration type dust collector such as a bag filter is used. The air after dust discharged from the dust collector 26 can be used as primary air and / or secondary air of the fluidized bed incinerator 10.
[0019]
The deposit collected by the dust collector 26 is used as a drug after being subjected to processing such as particle size adjustment as necessary. According to the test, most of the collected deposits are fine powder of about 40 to 80 μm and contain Ca compound (CaO etc.), and as shown in FIG. It can be used as a substitute for a desalting agent (such as slaked lime) blown in front of a dust collector 28 (filtered dust collector such as a bag filter) installed in an exhaust gas treatment system of an incinerator. Since the dust of the deposit | attachment removed by the deposit | attachment removal apparatus 12 originates in ash, it is necessary to perform the process similar to the ash from an incinerator. An increase in the amount of ash treatment leads to an increase in the scale of the processing apparatus, and the running cost of the apparatus also increases. Therefore, as described above, using collected dust collected as a substitute for a desalting agent suppresses the amount of ash discharged and leads to a reduction in drug costs. In addition, as a utilization method as a chemical | medical agent of the collected deposit | attachment, it can utilize not only as said desalting agent but as a desulfurization agent, an adsorption agent, etc.
[0020]
In the present embodiment, the fluidized medium is extracted during operation of the apparatus to regenerate the fluidized medium and optimize the particle size, and the fluidized medium is extracted when the apparatus is stopped (such as during periodic inspection). There are cases where the medium is regenerated and the particle size is optimized. In the case of operation, for example, an appropriate amount of a fluid medium is extracted, treated with a removing device for a predetermined time, and circulated in a fluidized bed furnace. On the other hand, at the time of stopping, for example, the entire amount of the fluidized medium is extracted, and after the processing is performed until the deposits can be almost completely removed by the removing device, the fluidized medium is returned to the fluidized bed furnace. Of course, other operation methods are possible.
[0021]
FIG. 6 shows an example of a fluidized bed incinerator equipped with a fluid medium deposit removing device according to a second embodiment of the present invention. In the fluidized bed incinerator where the fuel containing the Ca component (RDF or the like) is combusted or the Ca compound is added to combust waste, RDF, coal, etc. It removes the adhered substances. The BM extracted from the lower part of the fluidized bed incinerator 10 together with incombustibles is separated into incombustibles with a sieve (not shown), and then put into a deposit removal device 30 that is manufactured by modifying the BM storage tank. Is done. Thus, in this Embodiment, BM storage tank is used as a deposit removal apparatus main body. High-speed air is blown into the fluid medium group stored in the adhering substance removing device 30, and the adhering substance is removed by the wear action between the fluid media, so that the fluid medium is regenerated and the particle diameter is optimized.
[0022]
For example, as shown in FIG. 6, the deposit removing device 30 manufactured by modifying the BM storage tank can be configured to blow air from the lower portion of the fluid medium group through the air diffuser 32. The deposit removing device 30 may be configured to blow air from the lower side of the fluid medium group using a nozzle on the dispersion plate.
[0023]
The treated BM having an optimized particle diameter is extracted from the deposit removing device 30 and returned to the fluidized bed incinerator 10 through the BM circulation line 24. Further, the removed deposit is collected by a dust collector 26 (a filtration type dust collector such as a bag filter) installed at the rear stage of the deposit removing device 30. The air after dust discharged from the dust collector 26 can be used as primary air and / or secondary air of the fluidized bed incinerator 10. The deposit collected by the dust collector 26 is used as a drug after being subjected to processing such as particle size adjustment as necessary. Specifically, for example, as shown in FIG. 6, an alternative to a desalting agent blown in front of a dust collector 28 (filtered dust collector such as a bag filter) installed in an exhaust gas treatment system of an incinerator. It can be used as a substance. In addition, as a utilization method as a chemical | medical agent of the collected deposit | attachment, it can utilize not only as said desalting agent but as a desulfurization agent, adsorption agent, etc.
Other configurations and operations are the same as those in the first embodiment.
[0024]
FIG. 7 shows an example of a fluidized bed incinerator equipped with a fluid medium deposit removing device according to a third embodiment of the present invention. As an example, this embodiment is a case where the fluidized bed incinerator is a circulating fluidized bed furnace, in which a fuel containing Ca (such as RDF) is burned, or a Ca compound is added to produce waste or RDF or In a fluidized bed furnace for burning coal or the like, a substance attached to the fluidized medium is removed. In the circulating fluidized bed furnace 34, BM is extracted from the heat collecting fluidized bed 38 installed at the subsequent stage of the cyclone 36, and the extracted BM is supplied to the deposit removing device 12. Thus, in this Embodiment, the deposit | attachment removal apparatus 12 is installed separately from the BM storage tank 14. FIG. High-speed air is blown into the fluid medium group in the deposit removal device 12, the deposits are removed by the wear action of the fluid media, and the fluid medium is regenerated and the particle diameter is optimized.
[0025]
The treated BM having an optimized particle size is extracted from the BM outlet 22 of the deposit removing device 12 and returned to the fluidized bed furnace 34 through the BM circulation line 24. In this case, the treated BM can be returned to the BM storage tank 14. The BM outlet of the deposit removing device 12 is not limited to the bottom of the device, but may be provided on the side surface of the device. Further, the removed deposits are collected by a dust collecting device 26 installed at the rear stage of the deposit removing device 12. The dust-removed air discharged from the dust collector 26 can be used as primary air and / or secondary air in the fluidized bed furnace 34.
[0026]
The deposit collected by the dust collector 26 is used as a drug after being subjected to processing such as particle size adjustment as necessary. Most of the collected deposits are fine powders of about 40 to 80 μm and contain Ca compounds (CaO, etc.), and smoke cleaning chemicals such as exhaust gas from incinerators as shown in FIG. It can be used as a substitute for a desalting agent (slaked lime, etc.) blown in front of a dust collector 28 (filter type dust collector such as a bag filter) installed in the treatment system. In addition, as a utilization method as a chemical | medical agent of the collected deposit | attachment, it can utilize not only as said desalting agent but as a desulfurization agent, an adsorption agent, etc.
Other configurations and operations are the same as those in the first embodiment.
[0027]
FIG. 8 shows an example of a fluidized bed incinerator equipped with a fluidized medium deposit removing device according to a fourth embodiment of the present invention. This embodiment is also an example in which the fluidized bed incinerator is a circulating fluidized bed furnace, in which a fuel containing Ca content (such as RDF) is burned, or a Ca compound is added to produce waste or RDF. In a fluidized bed furnace for burning coal or the like, a substance attached to the fluidized medium is removed. In the circulating fluidized bed furnace 34, BM is extracted from a fluidized bed 38 for heat collection installed at the subsequent stage of the cyclone 36, and the extracted BM modifies the BM storage tank to produce the deposit removing device 30. It is thrown into. Thus, in this Embodiment, BM storage tank is used as a deposit removal apparatus main body. High-speed air is blown into the fluid medium group stored in the adhering substance removing device 30, and the adhering substance is removed by the wear action between the fluid media, so that the fluid medium is regenerated and the particle diameter is optimized.
[0028]
The treated BM having an optimized particle size is extracted from the deposit removing device 30 and returned to the fluidized bed furnace 34 through the BM circulation line 24. Further, the removed deposit is collected by a dust collector 26 (a filtration type dust collector such as a bag filter) installed at the rear stage of the deposit removing device 30. The dust-removed air discharged from the dust collector 26 can be used as primary air and / or secondary air in the fluidized bed furnace 34. The deposit collected by the dust collector 26 is used as a drug after being subjected to processing such as particle size adjustment as necessary. Specifically, for example, as shown in FIG. 8, an alternative to a desalting agent blown in front of a dust collector 28 (filtered dust collector such as a bag filter) installed in an exhaust gas treatment system of an incinerator. It can be used as a substance. In addition, as a utilization method as a chemical | medical agent of the collected deposit | attachment, it can utilize not only as said desalting agent but as a desulfurization agent, an adsorption agent, etc.
Other configurations and operations are the same as those in the first, second, and third embodiments.
[0029]
【The invention's effect】
Since this invention is comprised as mentioned above, there exist the following effects.
(1) The fluidized medium enlarged with deposits in the fluidized bed incinerator is once extracted out of the furnace, and high-speed air is blown into the fluidized medium to remove the substances adhering to the fluidized medium. Since the diameter is optimized, it is easy to maintain an appropriate fluid state in the fluidized bed incinerator.
(2) Since the fluidization start speed does not increase, the utility of ventilation systems such as blowers will not increase. Moreover, since the amount of exhaust gas from the fluidized bed furnace does not increase, the utility of the exhaust gas treatment system does not increase.
(3) Since only high-speed air is blown into the fluid medium extracted during operation, the fluid medium itself is not subjected to thermal shock due to a rapid temperature change, and the fluid medium is not easily crushed.
(4) Since the deposits are removed outside the furnace, the causative substances are not concentrated in the furnace.
(5) Since there is no moving part in the removing apparatus and only air blowing means is provided, the structure is very simple and simple, and the apparatus is not easily damaged by the fluid medium.
(5) In the case of a fluidized bed incinerator in which a fuel containing Ca and / or Mg or a Ca compound and / or Mg compound is added and combusted, the collected deposit powder is, for example, waste It can be used as a substitute for a desalting agent blown before a dust collector in an exhaust gas treatment system such as an incinerator. The collected deposit powder can also be used as an adsorbent or a desulfurizing agent.
[Brief description of the drawings]
FIG. 1 is a schematic configuration explanatory view showing a fluidized bed incinerator equipped with a fluidized medium deposit removal device according to a first embodiment of the present invention.
FIG. 2 is an enlarged configuration explanatory view showing an example of an air blowing structure of the deposit removing apparatus according to the first embodiment of the present invention.
FIG. 3 is a schematic schematic plan view illustrating an example of an air blowing direction of the deposit removing apparatus according to the first embodiment of the present invention.
FIG. 4 is a schematic schematic plan view illustrating another example of the air blowing direction of the deposit removing apparatus according to the first embodiment of the present invention.
FIG. 5 is a schematic schematic plan view showing still another example of the air blowing direction of the deposit removing apparatus according to the first embodiment of the present invention.
FIG. 6 is a schematic configuration explanatory view showing a fluidized bed incinerator equipped with a fluid medium deposit removal device according to a second embodiment of the present invention.
FIG. 7 is a schematic configuration explanatory view showing a fluidized bed incinerator equipped with a fluid medium deposit removing device according to a third embodiment of the present invention.
FIG. 8 is a schematic configuration explanatory view showing a fluidized bed incinerator equipped with a fluid medium deposit removing device according to a fourth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Fluidized bed incinerator 12, 30 Deposit removal apparatus 14 BM storage tank 16 Blower 18 Dispersion plate 20 Nozzle 22 BM outlet 24 BM circulation line 26, 28 Dust collector 32 Aeration pipe 34 Circulating fluidized bed furnace 36 Cyclone 38 Collection Fluidized bed for heat

Claims (6)

The fluid medium enlarged by deposits is extracted from the fluidized bed incinerator in which fuel containing Ca and / or Mg is added or Ca compound and / or Mg compound is added and burned. The extracted fluidized medium is put into a deposit removal device, and air is blown into the device to remove substances adhered to the fluidized medium, and the fluidized medium is regenerated and the particle size is optimized. A method for removing deposits from a fluid medium, characterized in that the collected deposits are collected by a dust collector, and the collected deposits are used as any one of a desalting agent, a desulfurizing agent and an adsorbent .   2. The fluidized medium according to claim 1, wherein the fluidized bed incinerator is a circulating fluidized bed furnace, and the fluidized medium enlarged by deposits is extracted from the fluidized bed for heat recovery in the circulating fluidized bed furnace and is put into the deposit removing device. How to remove deposits.   The removal method of the deposit | attachment of the fluid medium of Claim 1 or 2 using the air after dust removal discharged | emitted from a dust collector as primary air and / or secondary air of a fluidized bed incinerator. A fluidized bed incinerator in which a fuel containing Ca and / or Mg is charged or burned by adding a Ca compound and / or Mg compound;
Fluid medium extraction means for extracting the fluid medium enlarged by deposits from the fluidized bed incinerator;
A deposit removing device that removes a substance attached to the fluid medium by storing the fluid medium extracted outside the furnace and blowing air into the fluid medium group;
A dust collecting device for collecting the removed deposits installed downstream of the deposit removing device;
Collected deposit blowing means for blowing the collected deposit powder into the exhaust gas treatment system of the incinerator as a substitute for desalting agent and adsorbent,
Including a fluidized medium circulation system for removing the deposits and optimizing the particle size and extracting the fluidized medium from the deposit removing device and returning it to the fluidized bed incinerator and / or the fluidized medium storage tank. A fluidized bed incinerator equipped with a fluidized medium deposit removing device. The fluidized bed incinerator is a circulating fluidized bed furnace, and a fluidized medium extraction means is provided in the fluidized bed for heat recovery in the circulating fluidized bed furnace so that the fluidized medium enlarged by the deposits is put into the deposit removing device. A fluidized bed incinerator comprising the fluid medium deposit removing device according to claim 4 .   6. Removal of fluid medium deposits according to claim 4 or 5, further comprising an air supply system for using the air after dust removal discharged from the dust collector as primary air and / or secondary air in a fluidized bed incinerator. Fluidized bed incinerator equipped with equipment.

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