JP2017078517A - Fluidized bed system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To move a fluid medium at a low cost while preventing property change of the fluid medium.SOLUTION: A fluidized bed system 100 includes a first fluidized bed chamber 212 in which a fluidized bed of a fluid medium is formed, a second fluidized bed chamber 232 which is separately formed from the first fluidized bed chamber 212 and in which a fluidized bed of the fluid medium is formed, a communication pipe 250 for connecting a first portion 212c predetermined on a side wall 212a constituting the first fluidized bed chamber 212 and a second portion 232c predetermined on a side wall 232a constituting the second fluidized bed chamber 232, an introduction control section 262 for controlling an introduction amount of the fluid medium introduced into the first fluidized bed chamber 212 so that a bed height of the fluidized bed formed in the first fluidized bed chamber 212 is higher than the first portion 212c, and a pressure control section 264 for maintaining a pressure in the second fluidized bed chamber 232 to be lower than in the first fluidized bed chamber 212.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fluidized bed system that moves a fluidized medium from a first fluidized bed chamber in which a fluidized bed of a fluidized medium is formed to a second fluidized bed chamber.

  A fluidized bed system using a fluidized bed formed by jetting gas from the bottom to the top of a fluidized bed chamber in which particulate solids are accommodated is used to dry, burn, gasify, and granulate solids. It is used in various fields. In such a fluidized bed system, a plurality of fluidized bed chambers are provided for changing the conditions of the fluidized bed (temperature, atmosphere, etc.), limiting the installation area (installation volume), and ensuring controllability. There are also things.

  In a fluidized bed system having a plurality of fluidized bed chambers, as a technique for moving solids (fluid medium) from the first fluidized bed chamber to the second fluidized bed chamber, a conveyor after taking out the fluidized medium from the first fluidized bed chamber And moving the first fluidized bed chamber above the second fluidized bed chamber and communicating the first fluidized bed chamber and the second fluidized bed chamber. A technique (for example, Patent Document 2) has been developed in which a fluid medium is moved by its own weight through a pipe connected through a communication pipe.

JP 2002-095952 A Japanese Patent No. 4083409

  However, in the technique using the conveyor as described in Patent Document 1, since the fluid medium is exposed to air in the movement process, the fluid medium reacts with substances in the air such as oxygen and water, In the case of an adsorbing substance, there is a problem that the properties of the fluid medium change during the movement process.

  The technique for varying the installation height of the fluidized bed chamber described in Patent Document 2 occupies a wide area, so that the installation location is limited. In addition, there is a problem that one fluidized bed chamber needs to be provided at a high place, resulting in an increase in installation cost.

  Therefore, in view of such a problem, an object of the present invention is to provide a fluidized bed system capable of moving a fluidized medium at a low cost while preventing changes in properties of the fluidized medium.

  In order to solve the above-described problems, a fluidized bed system of the present invention includes a first fluidized bed chamber in which a fluidized bed of a fluidized medium is formed, and a fluidized bed of fluidized medium formed separately from the first fluidized bed chamber. A second fluidized bed chamber to be formed; a first predetermined location on the side wall constituting the first fluidized bed chamber; and a second predetermined location on the side wall constituting the second fluidized bed chamber. Introduction for controlling the amount of fluid medium introduced into the first fluidized bed chamber so that the communicating pipe and the fluidized bed formed in the first fluidized bed chamber are above the first location. A control unit and a pressure control unit for maintaining the second fluidized bed chamber at a lower pressure than the first fluidized bed chamber are provided.

  In addition, a first exhaust part for discharging gas from a first free board part formed above the fluidized bed in the first fluidized bed room, and a second free board formed above the fluidized bed in the second fluidized bed room And a second exhaust part that exhausts gas from the part, and the pressure control part has an exhaust flow rate of each of the first exhaust part and the second exhaust part according to the pressure in the first fluidized bed chamber and the second fluidized bed chamber May be controlled.

  Moreover, it is good also as providing the extraction part which extracts a part of fluid medium which stayed in the lower part in a 1st fluidized bed chamber.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to move a fluid medium at low cost, preventing the property change of a fluid medium.

It is a figure explaining a fluid bed system.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Fluidized bed system 100)
FIG. 1 is a diagram illustrating a fluidized bed system 100. In the present embodiment, a configuration in which the fluidized bed system 100 dries lignite as a fluidized medium will be described as an example. In FIG. 1, the gas flow is indicated by solid arrows, the flow of the fluid medium is indicated by dashed-dotted arrows, and the signal flow is indicated by broken arrows. As shown in FIG. 1, the fluidized bed system 100 includes an introduction unit 110, a moisture sensor 120, a first fluidized bed unit 210, a second fluidized bed unit 230, a communication pipe 250, and a central control unit 260. Consists of including.

(Introducing means 110, moisture sensor 120)
The introducing means 110 includes a conveyor 112 that conveys lignite, a hopper 114 that temporarily stores the lignite conveyed by the conveyor 112, and lignite from the hopper 114 to the first fluidized bed portion 210 (first fluidized bed chamber 212). And an introduction valve 116 to be introduced. In the present embodiment, the introduction means 110 is configured so that the bed height of the fluidized bed formed in the first fluidized bed chamber 212 is higher than the first location 212c described later in accordance with the control by the introduction control unit 262 described later. The lignite is introduced into the first fluidized bed chamber 212 in such an introduction amount as follows.

  The moisture sensor 120 measures the moisture content of the lignite introduced into the first fluidized bed portion 210 by the introduction means 110. As the moisture sensor 120, for example, a moisture sensor such as a near infrared absorption method or a microwave absorption method can be adopted.

(First fluidized bed 210)
The first fluidized bed unit 210 includes a first fluidized bed chamber 212, a first fluidized gas supply unit 214, a first heat transfer unit 216, an extraction unit 218, a first exhaust unit 220, and a first pressure. A sensor 222 is included.

  The first fluidized bed chamber 212 accommodates the lignite introduced by the introducing means 110. The first fluidizing gas supply unit 214 supplies a first fluidizing gas (for example, water vapor) from the bottom surface of the first fluidized bed chamber 212. More specifically, the first fluidizing gas supply unit 214 includes an air box 214a, a first fluid pipe 214b, and a first blower 214c. The air box 214a is provided below the first fluidized bed chamber 212, and the upper portion of the air box 214a also functions as a bottom surface of the first fluidized bed chamber 212 and is formed of a dispersion plate 214d that can be ventilated. The dispersion plate 214d is configured by, for example, a plate provided with a plurality of apertures having a diameter smaller than the particle size of lignite, or a plate provided with a nozzle provided with an aperture having a diameter smaller than the particle size of lignite. .

  The first flow pipe 214b is connected to the wind box 214a, and the first flow pipe 214b is provided with a first blower 214c for feeding the first fluidizing gas. Therefore, when the fluidized bed system 100 is operated, the first fluidized gas is supplied into the first fluidized bed chamber 212 from the bottom surface of the first fluidized bed chamber 212 through the wind box 214a.

  Thus, the first fluidized gas is supplied into the first fluidized bed chamber 212 by the first fluidized gas supply unit 214, and the first fluidized gas causes the lignite to flow in the first fluidized bed chamber 212, A part of the water contained in the lignite is vaporized by forming the fluidized bed and bringing the first fluidizing gas into contact with the lignite.

  The first heat transfer unit 216 is constituted by, for example, a pipe through which a heat medium flows, and is arranged in the first fluidized bed chamber 212. The 1st heat-transfer part 216 heats lignite with the heat | fever which a heat medium has in the distribution | circulation process of a heat medium. With the configuration including the first heat transfer section 216, heat exchange is performed between the heat medium and the first fluidizing gas in the first fluidized bed chamber 212, and the first fluidizing gas that moves upward is further added. Can be heated. Therefore, drying of lignite with the first fluidizing gas is further promoted.

  The extraction part 218 includes an extraction pipe 218a connected to the lower part of the side wall 212a constituting the first fluidized bed chamber 212, and an extraction valve 218b provided in the extraction pipe 218a. Part of the lignite staying in the lower part of the fluidized bed chamber 212 is extracted to the outside. The effect of the extraction part 218 will be described in detail later.

  The first exhaust part 220 includes a first exhaust pipe 220a connected to the upper wall of the first fluidized bed chamber 212 and a first exhaust valve 220b provided in the first exhaust pipe 220a. Gas is discharged from the space (first free board portion 212b) formed above the fluidized bed in the layer chamber 212.

  The first pressure sensor 222 measures the pressure in the first fluidized bed chamber 212 (the pressure of the first free board portion 212b).

  Thus, in the 1st fluidized bed part 210, undried lignite is introduce | transduced in the 1st fluidized bed chamber 212, lignite is heated by the 1st fluidization gas supply part 214 and the 1st heat transfer part 216, and lignite A part of the water is vaporized and removed. On the other hand, when the flow of lignite is described, lignite moves from the first fluidized bed chamber 212 to the second fluidized bed chamber 232 through the communication pipe 250 in accordance with control by the central control unit 260 described later. The movement of lignite through the communication pipe 250 will be described in detail later.

(Second fluidized bed 230)
The second fluidized bed section 230 includes a second fluidized bed chamber 232, a second fluidized gas supply section 234, a second heat transfer section 236, an overflow section 238, a second exhaust section 240, and a second pressure sensor. 242 is comprised.

  The second fluidized bed chamber 232 is formed separately from the first fluidized bed chamber 212 and accommodates lignite introduced from the first fluidized bed chamber 212 through the communication pipe 250. The second fluidizing gas supply unit 234 supplies the second fluidizing gas (for example, water vapor) from the bottom surface of the second fluidized bed chamber 232. More specifically, the second fluidizing gas supply unit 234 includes an air box 234a, a second fluid pipe 234b, and a second blower 234c, like the first fluidizing gas supply unit 214. The The air box 234a is provided below the second fluidized bed chamber 232, and the upper portion of the air box 234a also functions as a bottom surface of the second fluidized bed chamber 232 and is formed of a dispersion plate 234d that can vent. The dispersion plate 234d is constituted by, for example, a plate provided with a plurality of openings having a diameter smaller than the particle size of lignite, or a plate provided with a nozzle provided with an opening having a diameter smaller than the particle size of lignite. .

  The second fluid pipe 234b is connected to the wind box 234a, and the second fluid pipe 234b is provided with a second blower 234c for feeding the second fluidizing gas. Therefore, when the fluidized bed system 100 is operated, the second fluidized gas is supplied into the second fluidized bed chamber 232 from the bottom surface of the second fluidized bed chamber 232 through the wind box 234a.

  Thus, the second fluidized gas is supplied into the second fluidized bed chamber 232 by the second fluidized gas supply unit 234, and the second fluidized gas causes the lignite to flow in the second fluidized bed chamber 232, thereby In addition to forming a fluidized bed, a part of the water contained in the lignite is vaporized by bringing the second fluidized gas into contact with the lignite.

  The second heat transfer unit 236 is constituted by, for example, a pipe through which a heat medium flows, and is arranged in the second fluidized bed chamber 232. The second heat transfer unit 236 heats the lignite with the heat of the heat medium in the flow process of the heat medium. With the configuration including the second heat transfer section 236, heat exchange is performed between the heat medium and the second fluidizing gas in the second fluidized bed chamber 232, and the second fluidizing gas that moves upward is further added. Can be heated. Therefore, drying of the lignite with the second fluidizing gas is further promoted.

  The overflow part 238 includes an overflow pipe 238a connected to an outlet provided at an upper part of the side wall 232a constituting the second fluidized bed chamber 232, and an overflow valve 238b provided in the overflow pipe 238a. 2 Brown coal overflowed from the outlet of the fluidized bed chamber 232 is sent to the outside. More specifically, when lignite is introduced into the second fluidized bed chamber 232 from the first fluidized bed portion 210 (in the first fluidized bed chamber 212) through the communication pipe 250, the volume of the introduced lignite, The volume of the fluidized bed increases. As a result, lignite (fluidized bed) overflows from the outlet of the second fluidized bed chamber 232 (where the second fluidized bed chamber 232 is connected to the overflow pipe 238a) and is sent to the outside through the overflow pipe 238a.

  The second exhaust part 240 includes a second exhaust pipe 240a connected to the upper wall of the second fluidized bed chamber 232 and a second exhaust valve 240b provided in the second exhaust pipe 240a. Gas is discharged from the space (second free board portion 232b) formed above the fluidized bed in the bed chamber 232.

  The second pressure sensor 242 measures the pressure in the second fluidized bed chamber 232 (the pressure of the second free board part 232b).

(Communication pipe 250)
The communication pipe 250 includes a predetermined first location 212c in the side wall 212a constituting the first fluidized bed chamber 212, and a predetermined second location 232c in the side wall 232a constituting the second fluidized bed chamber 232. Communicate. In the present embodiment, the first location 212c is located above the location where the extraction pipe 218a is connected, and the height of the first location 212c is substantially equal to the height of the second location 232c. The communication pipe 250 extends in the horizontal direction.

  In addition, as described above, the introduction unit 110 has an introduction amount in which the bed height of the fluidized bed formed in the first fluidized bed chamber 212 is higher than the first location 212c, and the lignite is introduced into the first fluidized bed chamber 212. Is introduced. Therefore, the inside of the communication pipe 250 is filled with a fluidized bed of lignite.

(Central control unit 260)
The central control unit 260 is composed of a semiconductor integrated circuit including a CPU (Central Processing Unit), reads programs and parameters for operating the CPU itself from the ROM, and cooperates with the RAM as a work area and other electronic circuits. Thus, the entire fluidized bed system 100 is managed and controlled. In the present embodiment, the central control unit 260 functions as the introduction control unit 262 and the pressure control unit 264.

  Specifically, the introduction control unit 262 first controls the conveyance speed of the conveyor 112 and the opening degree of the introduction valve 116 so that the bed height of the fluidized bed formed in the first fluidized bed chamber 212 is the first. The amount of fluid medium introduced into the first fluidized bed chamber 212 is controlled so as to be above the portion 212c.

  On the other hand, the pressure control unit 264 is based on the measurement value of the moisture sensor 120 so that the lignite sent from the overflow unit 238 of the second fluidized bed chamber 232 is dried to the target value. The residence time of lignite in the second fluidized bed chamber 232 is derived. For example, when the measured value of the moisture sensor 120 is relatively large, that is, when the moisture content of undried lignite is high, the residence time becomes long, and when the measured value of the moisture sensor 120 is relatively small, that is, When the moisture content of undried lignite is low, the residence time is shortened.

  Then, the pressure control unit 264 derives the moving speed of the lignite based on the volumes of the first fluidized bed chamber 212 and the second fluidized bed chamber 232 stored in a memory (not shown) and the derived residence time. . Subsequently, the pressure control unit 264 refers to the measurement values of the first pressure sensor 222 and the second pressure sensor 242, and the inside of the second fluidized bed chamber 232 is maintained at a lower pressure than the inside of the first fluidized bed chamber 212. The exhaust flow rates of the first exhaust unit 220 and the second exhaust unit 240 are controlled so that the moving speed of the brown coal becomes the derived moving speed.

  Then, the introduction control unit 262 maintains the introduction amount in which the bed height of the fluidized bed formed in the first fluidized bed chamber 212 is higher than the first location 212c, while introducing the fluidized bed into the first fluidized bed chamber 212. The conveyance speed of the conveyor 112 and the opening degree of the introduction valve 116 are controlled so that the introduction speed of lignite becomes equal to the movement speed.

  As described above, since the communication pipe 250 is filled with the fluidized bed, the second fluidized bed chamber 232 can be removed from the first fluidized bed chamber 212 only by making the pressure of the second fluidized bed chamber 232 lower than the pressure of the first fluidized bed chamber 212. The lignite can be automatically moved to the two fluidized bed chamber 232. In addition, the configuration including the introduction control unit 262 and the pressure control unit 264 makes it possible to move the lignite from the first fluidized bed chamber 212 to the second fluidized bed chamber 232 at a desired moving speed.

  As described above, according to the fluidized bed system 100 according to the present embodiment, the lignite can be moved only by adjusting the pressures of the first fluidized bed chamber 212 and the second fluidized bed chamber 232, so that the conveyor Unlike the prior art which moves between fluidized bed chambers using, it is possible to avoid a situation where lignite is exposed to air during the moving process. Therefore, it is possible to prevent lignite from reacting with substances in the air or adsorbing substances in the air, and it is possible to avoid changes in the properties of lignite during the movement process.

  In addition, since the dried lignite in a high temperature state may be burned by reacting with oxygen in the air, in the conventional technology that moves between fluidized bed chambers using a conveyor, an apparatus having a drive unit such as a conveyor is provided. There was a problem that it was necessary to provide a sealed structure, or to provide fire extinguishing equipment, resulting in high costs. However, in the fluidized bed system 100 according to the present embodiment, since the lignite moves through the communication pipe 250 partitioned from the outside due to a pressure difference (differential pressure), the sealing of the device including the drive unit is performed. No structure or fire extinguishing equipment is required, and the cost can be reduced. Moreover, since it is not necessary to make the installation height of the 1st fluidized bed chamber 212 and the 2nd fluidized bed chamber 232 different, installation cost can also be reduced.

  Further, for example, when the first fluidizing gas is supplied from the first fluidizing gas supply unit 214 (first blower 214c) at a flow rate at which the lignite having the average particle diameter is optimally fluidized, the particle diameter larger than the average particle diameter. Some of the lignite (or high mass) is not fluidized. Moreover, since the 1st location 212c to which the communication pipe 250 is connected is distribute | arranged to the upper part of the 1st fluidized bed chamber 212, a large particle size brown coal is not guide | induced to the communicating pipe 250, but a 1st fluidized bed chamber 212 will remain.

  Therefore, by providing an extraction portion 218 for extracting a part of the lignite staying in the lower part of the first fluidized bed chamber 212, it becomes possible to extract the lignite that is not fluidized to the outside, and the lignite in the first fluidized bed chamber 212. Can be avoided. Thereby, it becomes possible to avoid the situation where a fluidized bed is no longer formed by the remaining lignite.

  Moreover, since the extraction part 218 extracts lignite that is not fluidized from the first fluidized bed chamber 212, lignite that is not fluidized is not introduced into the second fluidized bed chamber 232, and remains in the second fluidized bed chamber 232. It becomes possible to omit the extraction section dedicated to lignite (fluid medium).

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  For example, in the above embodiment, lignite has been described as an example of the fluid medium. However, there is no limitation on the type of fluid medium as long as it is a particulate solid.

  Moreover, in the said embodiment, the 1st location 212c to which the communication pipe | tube 250 is connected was mentioned as an example, and the structure located above the location to which the extraction pipe | tube 218a is connected was demonstrated. However, the first location 212c may be a location lower than the bed height of the fluidized bed, and is substantially equal to the location where the extraction pipe 218a is connected or below the location where the extraction pipe 218a is connected. May be located.

  Moreover, in the said embodiment, the height of the 1st location 212c and the height of the 2nd location 232c were substantially equal, and it demonstrated and demonstrated as an example the structure where the communicating pipe 250 extended in a horizontal direction. However, the height relationship between the first location 212c and the second location 232c is not limited, and the communication pipe 250 may be inclined in the vertical direction.

  In the above embodiment, the fluidized bed system 100 includes the first pressure sensor 222 and the second pressure sensor 242, and the pressure control unit 264 is configured according to the measurement values of the first pressure sensor 222 and the second pressure sensor 242. The configuration in which the second fluidized bed chamber 232 is maintained at a lower pressure than the first fluidized bed chamber 212 has been described as an example. However, if the pressure control unit 264 can maintain the inside of the second fluidized bed chamber 232 at a lower pressure than the inside of the first fluidized bed chamber 212, the first pressure sensor 222 and the second pressure sensor 242 are not essential components. For example, the second fluidized bed chamber is based on the flow rate of the first fluidized gas supplied from the first blower 214c to the wind box 214a and the flow rate of the second fluidized gas supplied from the second blower 234c to the wind box 234a. The opening degree of the first exhaust valve 220b and the opening degree of the second exhaust valve 240b may be controlled so that 232 is maintained at a lower pressure than the first fluidized bed chamber 212.

  The present invention can be used in a fluidized bed system that moves a fluidized medium from a first fluidized bed chamber in which a fluidized bed of a fluidized medium is formed to a second fluidized bed chamber.

100 Fluidized bed system 212 First fluidized bed chamber 212a Side wall 212b First free board part 212c First part 218 Extraction part 220 First exhaust part 232 Second fluidized bed room 232a Side wall 232b Second free board part 232c Second Location 240 Second exhaust part 250 Communication pipe 262 Introduction control part 264 Pressure control part

Claims (3)

A first fluidized bed chamber in which a fluidized bed of fluidized media is formed;
A second fluidized bed chamber formed separately from the first fluidized bed chamber, in which a fluidized bed of a fluidized medium is formed;
A communication pipe that communicates a predetermined first location on the side wall constituting the first fluidized bed chamber and a predetermined second location on the side wall constituting the second fluidized bed chamber;
An introduction control unit that controls the introduction amount of the fluid medium introduced into the first fluidized bed chamber so that the bed height of the fluidized bed formed in the first fluidized bed chamber is higher than the first location. When,
A pressure control unit for maintaining the second fluidized bed chamber at a lower pressure than the first fluidized bed chamber;
A fluidized bed system characterized by comprising: A first exhaust part for exhausting gas from a first free board part formed above the fluidized bed in the first fluidized bed chamber;
A second exhaust part for exhausting gas from a second free board part formed above the fluidized bed in the second fluidized bed chamber;
With
The pressure controller is
2. The fluidized bed according to claim 1, wherein an exhaust flow rate of each of the first exhaust part and the second exhaust part is controlled in accordance with pressures in the first fluidized bed chamber and the second fluidized bed chamber. system.   3. The fluidized bed system according to claim 1, further comprising an extraction unit that extracts a part of the fluidized medium staying in a lower part of the first fluidized bed chamber.

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