JP6944498B2 - Bubbling type fluidized bed reactor and fluidized bed bubbling state stabilization method - Google Patents

Description

The present invention mainly relates to a bubbling type fluidized bed reactor that heat-treats an object to be treated, and a bubbling state stabilizing method that stabilizes the bubbling state of the fluidized bed in the furnace.

Conventionally, a bubbling type fluidized bed reactor that heat-treats at least one of drying, pyrolysis, and combustion of a treatment object such as coal, biomass, and waste has been known. In this reactor, a considerable amount of fluidized gas such as air is ventilated from the bottom of the furnace into a fluidized medium such as silica sand filled in the lower part of the furnace, and the fluidized bed is allowed to flow under constant high temperature conditions. Form a fluidized bed. In this fluidized bed, the entire fluidized medium bubbling as if the liquid is boiling constitutes a fluidized bed. A fluidized medium in which the object to be treated charged at the interface of the fluidized bed is heated by a fluidized gas that passes through the fluidized bed and rises while rapidly sinking into the fluidized bed layer, a fluidized gas, and the like, and is moving violently. A thermal reaction involving at least one of drying, pyrolysis, and combustion proceeds, and the gas is instantly (and / or pyrolyzed, burned) in an instant (in a very short time).

The reactivity (speed of reaction) of the thermal reaction generated here depends on the intensity of the flow state of the fluidized medium bubbling in the fluidized bed. In general, the more intense the flow state of the fluid medium, the more pyrolysis and / or combustion is promoted and the higher the reactivity of the thermal reaction.

The intensity of the flow state of the flow medium is affected by the supply amount of the flow gas and the amount of gaseous substances (exhaust gas, unburned gas, water vapor, post-combustion fine particles, etc.) generated by the above thermal reaction. In general, the supply amount of the flowing gas is controlled so as not to change suddenly. Therefore, the intensity of the fluid state of the fluid medium depends mainly on the amount of gaseous substances generated by the thermal reaction of the object to be treated taken into the fluid medium layer.

Therefore, if the thermal reaction is enhanced for some reason locally on the entire surface of the fluidized bed, the amount of gaseous substances generated by the thermal reaction will increase rapidly. As the amount of gas passing through the location (mainly the amount of gaseous substances generated) increases rapidly, the flow state of the fluid medium in the location becomes intense, and the gaseous substance, the fluid medium, and the object to be treated And, the contact becomes fierce. This may lead to a vicious cycle in which the amount of gas generated is further increased while the thermal reaction of the object to be treated is promoted. When this happens, it causes excessive bubbling in a limited part of the fluidized bed.

When the above-mentioned enhancement of the local thermal reaction occurs, the amount of gaseous substances generated increases rapidly, and the pressure fluctuation in the furnace increases, while the secondary occurs in the space above the fluidized bed. It adversely affects the combustion completeness of combustion.

In addition, a downstream treatment facility (for example,) provided on the downstream side of the bubbling type fluidized bed reactor so that the post-treatment of the exhaust gas can be performed without any problem even if a sudden increase in the local thermal reaction occurs. , Combustion deodorization equipment, secondary combustion equipment, exhaust heat recovery equipment, exhaust gas treatment equipment, etc.) must be designed with a certain degree of redundancy.

However, in steady operation where a sudden increase in local thermal reaction does not occur, the margin provided in the downstream treatment equipment is idle, so various losses in equipment operation (for example, exhaust heat recovery amount) (Reduction, etc.) will occur. Therefore, conventionally, it has been desired to suppress such an increase in local thermal reaction.

In this regard, Patent Documents 1 and 2 propose methods for suppressing local thermal reactions, respectively.

In Patent Document 1, by significantly reducing the supply amount of the flowable gas near the central portion of the fluidized medium layer, the movement of the fluidized medium in the portion is suppressed, and the supply of the fluidized gas on the outer edge portion side of the fluidized medium layer is suppressed. By greatly increasing the amount, the flow medium of the relevant portion is made easy to pop out upward. As a result, a circulating flow of the flow medium is formed between the central portion and the outer edge portion of the flow medium layer, and the flow medium layer in which the object to be treated is mainly charged while maintaining the overall flow state of the flow medium layer. It is possible to greatly suppress the movement of the flow medium near the central part of the. As a result, Patent Document 1 states that the thermal reaction due to contact between the object to be treated and the fluid medium can be moderated.

In Patent Document 2, the supply amount of the flowable gas near the central portion of the fluidized medium layer is set to a neutral flow rate, and the supply amount of the fluidized gas near both sides of the fluidized medium layer sandwiching the central portion is set with respect to each of the supplied amounts of the fluidized gas. Compared to the vicinity of the central part, one side is more than the supply amount to the vicinity of the central part, and the other side is less than the supply amount to the vicinity of the central part. Further, in Patent Document 2, the supply amount of the flow gas to the vicinity of both side portions of the flow medium layer is alternately exchanged. As a result, Patent Document 2 states that the thermal reaction due to the contact between the object to be treated and the fluidized medium can be moderated by gentlening the average movement of the fluidized bed as a whole fluidized bed.

Japanese Unexamined Patent Publication No. 2-147692 Japanese Unexamined Patent Publication No. 1-291010

However, when the method of Patent Document 1 is used, since the flow medium in the central portion of the fluidized medium layer in the fluid state is hardly moving, the object to be processed that has fallen on the central portion remains on the fluidized medium layer. Resulting in. Further, the thermal reaction is promoted by the violent contact between the flow medium flying at high speed from the outer edge portion of the flow medium layer toward the central portion and the object to be treated remaining on the central portion. .. As a result, it is difficult to suppress the reactivity of the thermal reaction generated in the treated product, so that the effect of suppressing the enhancement of the local thermal reaction is not always sufficient.

Further, when the method of Patent Document 2 is used, three types of fluidized states having different intensities are formed on the entire surface of the fluidized bed interface. Of these three types of fluidized states, only one type of fluidized state has a mild thermal reaction due to contact between the object to be treated and the fluidized medium, and the other two types of fluidized medium layers are the same as before. Alternatively, since a more intense thermal reaction occurs than before, the effect of suppressing the enhancement of the local thermal reaction is not always sufficient.

The present invention has been made in view of the above circumstances, and its main purpose is to be able to simultaneously realize two types of fluidized beds having different intensities in the fluidized bed and to make the fluidized beds at the fluidized bed interface substantially the same. It is an object of the present invention to provide a bubbling type fluidized bed reactor and a method for stabilizing a fluidized bed bubbling state in a fluidized bed.

The problem to be solved by the present invention is as described above, and next, the means for solving this problem and its effect will be described.

From the viewpoint of the present invention, a bubbling type fluidized bed reactor having the following configuration is provided. That is, in this bubbling type fluidized bed type reactor, the fluidized bed is formed by blowing the fluidized gas from the bottom of the furnace into the fluidized bed filled in the lower part of the furnace, and the fluidized bed is formed into the object to be treated. On the other hand, at least one of drying, thermal decomposition, and combustion is heat-treated. The bubbling type fluidized bed reactor includes a plurality of infrared cameras and a control device. The plurality of infrared cameras are provided at a position looking down from the upper portion or the lateral upper portion of the fluidized bed interface, which is the upper interface of the fluidized bed, via a selective transmission filter that selectively transmits light having a wavelength not emitted by a flame. Then, thermal images are acquired from different viewpoints with respect to the fluidized bed interface. The control device creates a three-dimensional thermal image for the fluidized bed interface based on the thermal images acquired by the plurality of infrared cameras. The fluidized bed is composed of an upper fluidized bed and a lower fluidized bed arranged in the thickness direction, and the cross-sectional area when the upper fluidized bed is cut by a horizontal plane is horizontal to the lower fluidized bed. It is 1.4 times or more the cross-sectional area when cut on a flat surface. The fluidized gas is supplied to the lower fluidized bed. The control device increases or decreases the thickness of the fluidized bed in the furnace based on the created three-dimensional thermal image. The control device affects the bubbling state of the fluidized bed interface corresponding to a plurality of division units formed by dividing the created three-dimensional thermal image into a mesh shape in advance. Remember in association with. The control device calculates and stores the unit fluidized bed interface height, which is the average height of the fluidized bed interface in the divided unit, for each of the plurality of divided units based on the created three-dimensional thermal image. .. The control device increases or decreases the thickness of the upper fluidized bed in the furnace so as to maintain the height of the fluidized bed interface within an appropriate range based on the calculated unit fluidized bed interface height.

As a result, by providing the fluidized bed with two types of fluidized beds in the thickness direction, the entire surface of the fluidized bed interface is promoted to have almost the same fluidized state, and the fluidized state of the entire surface of the fluidized bed interface is gentle. Can be. As a result, it is possible to avoid the formation of locally different flow states. In addition, by making the flow state on the interface side of the flow bed gentle, in the initial stage of heat treatment for the object to be treated, the thermal reaction proceeds while suppressing the reactivity (speed of reaction), so that the temperature rises sharply and It is possible to avoid a rapid increase in the amount of gaseous substances generated. By appropriately adjusting the fluidized state of the upper fluidized bed, the height of the fluidized bed interface is maintained within an appropriate range, and the reactivity (speed of reaction) is appropriately maintained in the initial stage of heat treatment for the object to be treated. can do.

According to the present invention, two types of fluidized beds having different intensities can be simultaneously realized in the fluidized bed, and the fluidized beds can be made substantially the same at the fluidized bed interface.

The schematic diagram which shows the structure of the processing equipment including the bubbling type fluidized bed type reactor of this invention. The schematic diagram which shows the state of the flow gas passing through a flow medium layer. The figure which shows the example of the 3D thermal image of the fluidized bed interface.

<Rough Configuration of Processing Equipment> First, the configuration of the processing equipment 100 including the bubbling type fluidized bed type reactor 1 of the present embodiment will be described with reference to FIG. FIG. 1 is a schematic view showing the configuration of a processing facility 100 including a bubbling type fluidized bed reactor 1 of the present invention. In the following description, the terms "upstream" and "downstream" mean upstream and downstream in the direction in which the treatment product, combustion gas, exhaust gas, flow gas, etc. flow.

The treatment facility 100 is used to heat a treatment target such as coal, biomass, or refuse-derived fuel (RDF) at least one of drying, pyrolysis, and combustion. As shown in FIG. 1, the processing equipment 100 includes a bubbling type fluidized bed type reactor 1, a gas supply unit 4, a gas heating device 5, a downstream processing facility 6, a control device 9, and the like. The detailed configuration of the bubbling type fluidized bed reactor 1 will be described later.

The gas supply unit 4 includes a flow gas supply device 41 and a secondary combustion gas supply device 42. The fluidized gas supply device 41 supplies the fluidized gas into the bubbling type fluidized bed reactor 1. The secondary combustion gas supply device 42 supplies the secondary combustion gas used for the secondary combustion generated in the furnace. The flow gas supply device 41 and the secondary combustion gas supply device 42 can be composed of, for example, a blower, a blower, or the like.

The gas heating device 5 can heat the fluidized gas sucked from the outside by the fluidized gas supply device 41 before supplying it to the bubbling type fluidized bed reactor 1. For heating the fluidized gas, for example, the heat of the exhaust gas discharged from the bubbling type fluidized bed reactor 1 is used.

The downstream treatment facility 6 can treat the exhaust gas discharged from the bubbling type fluidized bed reactor 1. The downstream treatment equipment 6 is composed of, for example, combustion deodorization equipment, secondary combustion equipment, waste heat recovery equipment, exhaust gas treatment equipment, and the like.

The control device 9 is configured as, for example, a known computer. The control device 9 includes a CPU, RAM, ROM, HDD, etc. (not shown), performs various calculations, and controls the entire processing equipment 100. The storage unit included in the control device 9 stores various data for controlling the processing equipment 100. This storage unit is composed of the above ROM, HDD, and the like.

<Structure of Bubbling Type Fluidized Bed Reactor 1> As shown in FIG. 1, the bubbling type fluidized bed type reactor 1 includes a furnace body and an infrared camera 3. The furnace body is mainly composed of a freeboard unit 10, a fluidized bed unit 11, a fluidized gas supply unit 12, and a fluidized gas supply main pipe unit 13.

In the following, an example in which the bubbling type fluidized bed reactor 1 is used for incinerating the object to be treated will be described. A combustion chamber for incinerating the object to be treated is formed from the freeboard section 10 and the fluidized bed section 11.

The freeboard section 10 is a space inside the bubbling type fluidized bed reactor 1, and is an upper portion in the furnace excluding the fluidized bed section 11. A discharge port 10a is provided on the upper part of the freeboard portion 10. The bubbling type fluidized bed type reactor 1 can discharge the exhaust gas, the fine particles after combustion, and the like generated in the furnace from the discharge port 10a. The side wall of the freeboard portion 10 is provided with an inlet 10b and a secondary combustion air supply port 10c. The object to be processed is charged into the furnace through the charging port 10b. The secondary combustion air supply port 10c can supply the secondary combustion gas sent from the secondary combustion gas supply device 42 into the furnace.

The fluidized bed portion 11 is a space inside the furnace located below the freeboard portion 10. The fluidized bed portion 11 is filled with a fluidized medium such as silica sand. By aerating the fluidized gas through the fluidized bed in the fluidized bed portion 11, the fluidized bed is bubbled like a liquid. As a result, a fluidized bed in a bubbling state is formed. In the following description, the entire fluidized bed that is in a fluidized state due to bubbling in the fluidized bed may be referred to as a fluidized bed layer 11a. In this sense, the total height of the fluidized bed in the height direction of the bubbling type fluidized bed reactor 1 is the thickness of the fluidized bed layer 11a.

The filling amount of the fluidized medium in the fluidized bed portion 11 (fluidized bed layer 11a) is, for example, a fluidized medium from a fluidized medium storage unit (not shown) provided near or away from the bubbling type fluidized bed reactor 1. It can be increased by filling the furnace. On the other hand, by discharging the fluidized medium in the fluidized bed portion 11 to the fluidized medium storage unit, the filling amount of the fluidized medium in the fluidized bed portion 11 (fluidized bed portion 11a) can be reduced. The increase and decrease of the filling amount of the flow medium are automatically performed, for example, by the control device 9 operating the related device. The amount of flow medium may be changed by the operator manually operating the related device.

The fluidized gas supply unit 12 is provided below the fluidized bed unit 11. The flow gas supply unit 12 supplies the flow gas sent to the flow gas supply main pipe unit 13 to the flow medium layer 11a.

The flow gas supply unit 12 includes a flow rate adjusting device such as a damper (or valve) (not shown) and a flow meter. As a result, the flow gas supply unit 12 can supply the flow gas to all or a part of the plurality of locations at the bottom of the flow medium layer 11a. In other words, the flow gas is partially supplied to the bottom of the flow medium layer 11a through the flow gas supply unit 12, or the flow gas has a different flow rate to each part of the bottom of the flow medium layer 11a. Can be supplied. The flow rate adjusting device and the flow meter included in the flow gas supply unit 12 are configured to be communicable with the control device 9. The flow rate adjusting device is controlled by the control device 9.

The flow gas supply unit 12 can be configured in various types such as a "diffuse pipe method" that does not use a gas dispersion nozzle and a "dispersion plate method" that uses a gas dispersion nozzle. The type of the fluidized gas supply unit 12 can be determined in consideration of the characteristics of the bubbling type fluidized bed type reactor 1 in consideration of the type of the object to be treated, the type of heat treatment (thermal reaction in the furnace), and the like. .. The present invention can be applied regardless of the model of the flow gas supply unit 12.

The flow gas supply main pipe unit 13 is provided below the flow gas supply unit 12. The flowable gas is supplied to the flowable gas supply mother pipe portion 13 from the flowable gas supply device 41 via the gas heating device 5.

As shown in FIG. 1, the bubbling type fluidized bed reactor 1 is connected to the fluidized bed out-of-furnace discharge device 21 via a fluidized bed out-of-furnace discharge pipe 14. The flow medium out-of-furnace discharge pipe 14 is a passage connected to the bottom of the inside of the furnace (flow medium layer 11a). The flow medium out-of-furnace discharge pipe 14 can discharge the flow medium in the furnace and impurities such as incombustibles mixed in the flow medium to the outside of the furnace. The fluidized bed out-of-furnace discharge pipe 14 is not limited to one provided for the bubbling type fluidized bed reactor 1, and may be provided in a plurality.

By the operation of the fluidized bed out-of-furnace discharge device 21, the fluidized bed and impurities discharged from the bubbling type fluidized bed reactor 1 are sent to the contaminant classifier 22. The contaminant classifier 22 is used to separate contaminants from the fluidized medium discharged from the bubbling type fluidized bed reactor 1. The operation of the flow medium out-of-core discharge device 21 is controlled by the control device 9.

The fluidized bed return device 23 is arranged so as to connect the fluidized bed recovery port 22a of the contaminant classifier 22 and the bubbling type fluidized bed reactor 1. The fluidized medium from which the contaminants have been separated by the contaminant classifier 22 is returned to the bubbling type fluidized bed reactor 1 via the fluidized bed return apparatus 23.

The infrared camera 3 is composed of a camera for visualizing infrared rays emitted from an object. The infrared camera 3 may be a device whose main purpose is to capture a still image, or a device whose main purpose is to capture a moving image. Since a moving image is a plurality of continuous still images, the function of acquiring a thermal image is the same regardless of the device.

<Structure for Simultaneously Realizing Two Different Flow States> In the bubbling type fluidized bed reactor 1 of the present embodiment, as shown in FIG. 1, the fluidized bed portion 11 is the bubbling type fluidized bed reactor 1. It is composed of two upper and lower parts having different cross-sectional areas in the height direction.

Specifically, as shown in FIG. 1, the fluidized bed layer 11a in the fluidized bed portion 11 includes an upper fluidized bed layer portion (upper layer fluidized bed) 11b and a lower fluidized bed layer portion (lower fluidized bed). ) 11c and. The upper flow medium layer portion 11b and the lower flow medium layer portion 11c have different cross-sectional areas when cut in a horizontal plane. In the present embodiment, the cross-sectional area of the upper flow medium layer portion 11b is, for example, 1.4 times or more the cross-sectional area of the lower flow medium layer portion 11c.

When the flow rate of the fluid is constant, the flow velocity decreases as the cross-sectional area increases. Therefore, when a normal supply amount of the flow gas is supplied from the furnace bottom to the flow medium layer 11a (that is, the lower flow medium layer portion 11c), the flow velocity of the flow gas passes through the lower flow medium layer portion 11c. It is lower when passing through the upper flow medium layer portion 11b than when passing through the upper flow medium layer portion 11b. As a result, the flow state of the flow medium in the upper flow medium layer portion 11b becomes gentler than the flow state of the flow medium in the lower flow medium layer portion 11c. That is, two types of flow states having different intensities are formed in the upper flow medium layer portion 11b and the lower flow medium layer portion 11c.

In this way, by providing the fluidized bed layer 11a with two types of fluidized beds in the thickness direction, it is possible to encourage the fluidized bed layer 11a to have substantially the same fluidized state on the entire surface of the fluidized bed interface. As a result, the fluidized state of the entire surface of the fluidized bed interface can be moderated, and the formation of locally different fluidized beds can be avoided.

By the way, in the initial stage of heat treatment for the object to be treated, the proportion of water content in the object to be treated is often high. Therefore, if a strong thermal reaction occurs in the initial stage of the heat treatment, the water content in the object to be treated evaporates at once, and a large amount of water vapor (gaseous substance) is generated. As a result, the temperature rises sharply and the thermal reaction is accelerated more than necessary.

In this regard, in the bubbling type fluidized bed reactor 1 of the present embodiment, the fluidized bed layer 11a is configured to have two types of fluidized states, and in particular, the upper fluidized bed layer portion 11b that comes into contact with the object to be treated first. The fluidized state of is calm. Therefore, it is possible to prevent a violent thermal reaction from occurring in the initial stage of heat treatment of the object to be treated. That is, at the beginning of the heat treatment of the object to be treated, the thermal reaction is allowed to proceed while suppressing the reactivity (speed of reaction), thereby avoiding a rapid rise in temperature and a rapid increase in the amount of gaseous substances such as water vapor generated. be able to.

As a result, the fluctuation of the pressure in the furnace can be moderated, and the combustion completeness of the secondary combustion generated in the freeboard unit 10 can be maintained satisfactorily. In addition, since it is possible to suppress a rapid increase in exhaust gas, it is possible to design the downstream treatment equipment 6 with reduced redundancy.

<Gas Behavior> The flowable gas is sucked from the outside by the flowable gas supply device 41, pressurized to an appropriate pressure, and supplied to the flowable gas supply main pipe portion 13. The flow gas supplied to the flow gas supply main pipe unit 13 is supplied to the flow medium layer 11a via the flow gas supply unit 12.

The flowing gas is heated to an appropriate temperature by the gas heating device 5 while being sent from the flowing gas supply device 41 to the flow gas supply main pipe unit 13. However, when there is no need for heating, the flowable gas can be supplied to the flowable gas supply main pipe portion 13 without going through the gas heating device 5.

In order to heat the fluidized gas, in addition to the gas heating device 5, a heating device provided in the vicinity of the freeboard portion 10 or the like in the bubbling type fluidized bed type reactor 1 may be used. This heating device is composed of, for example, a device that heats using fuel or the like from the outside. As this heating device, a heating device that heats the freeboard unit 10 can be used.

The flow gas supplied to the flow medium layer 11a was taken into the flow medium layer 11a (sinking) while exchanging heat with the flow medium while passing through the flow medium layer 11a and rising. Upon contact with the object to be treated, at least one of drying, thermal decomposition, and combustion proceeds.

The flowable gas causes the flow medium layer 11a to flow by largely moving each flow medium particle in the flow medium layer 11a in various directions while proceeding with the above thermal reaction. By continuously passing an appropriate amount of flow gas through the entire flow medium layer 11a, the entire flow medium layer 11a can be maintained in an appropriate flow state.

The flow gas that has passed through the lower flow medium layer portion 11c of the flow medium layer 11a passes through the upper flow medium layer portion 11b at a slower speed due to the increase in the cross-sectional area of the flow medium layer 11a portion. As a result, the intensity of movement of the flow medium particles due to the flow of the flow gas is suppressed, and the rate of thermal reaction of the object to be treated due to contact with the flow gas and the flow medium particles is suppressed. That is, in the upper flow medium layer portion 11b, a milder thermal reaction is performed than in the lower flow medium layer portion 11c.

In the process in which the flow gas (and / or the gas after flow) that has passed through the flow medium layer 11a passes through the upper interface of the upper flow medium layer portion 11b toward the freeboard portion 10, the flow medium boils. appear. In the following description, the upper interface in the fluidized bed layer 11a through which the fluidizing gas passes upward while forming holes on the surface may be referred to as a fluidized bed interface.

The post-flow gas is a flow gas in which the above thermal reaction is completed inside the flow medium layer 11a and the internal components are changed. The after-flow gas has different components depending on the type of thermal reaction generated, and is composed of, for example, dry exhaust gas, pyrolysis gas, primary combustion gas, and the like.

The after-flow gas that has passed through the flow medium layer 11a rises to the upper freeboard portion 10. The secondary combustion gas supplied from the secondary combustion gas supply device 42 through the secondary combustion air supply port 10c is mixed with the flowable gas.

In the freeboard section 10, the secondary combustion reaction of the gas after flow proceeds due to the mixing of the secondary combustion gas. By burning the unburned component (and / or the incompletely burned component) contained in the gas after flow, the unburned component can be detoxified. The process of burning the unburned components (and / or incompletely burned components) in the gas after fluidization to make them harmless may be performed by a reactor provided separately from the bubbling type fluidized bed reactor 1. good.

The exhaust gas generated by the secondary combustion of the gas after flow is discharged to the downstream treatment facility 6. The exhaust gas is appropriately treated by the downstream treatment facility 6, such as exhaust heat recovery, cooling, and dust removal, and then discharged to the atmosphere by a chimney or the like.

<Solid behavior> The object to be processed sent by the dust supply device 24 is charged into the furnace via the charging port 10b. Since the charging port 10b is located above the fluidized bed layer 11a, the charged object to be processed naturally falls to the fluidized bed interface of the fluidized bed layer 11a. The object to be treated can be supplied to the dust supply device 24 from the outside via a supply device having each property and a treatment device such as crushing.

The dust supply device 24 puts the object to be treated into the bubbling type fluidized bed type reactor 1 from the outside. The dust supply device 24 can be composed of, for example, a supply conveyor or the like.

The object to be treated that has fallen to the interface of the fluidized bed is filled with the fluidized medium ejected upward (inside the freeboard portion 10) by the fluidized gas, and sinks inside the fluidized bed layer 11a due to the flow of the fluidized medium. .. The object to be treated that has sunk in the flow medium layer 11a is an individual flow medium particle that largely moves (moves violently) in various directions in the flow medium layer 11a, and a flow that passes through the flow medium layer 11a and rises. By contacting with the gas, the combustion reaction proceeds while being decomposed (miniaturized).

Since the velocity of the flowing gas passing through the upper flow medium layer portion 11b is relatively low, the movement of the flow medium is gentler than that of the lower flow medium layer portion 11c. As a result, the thermal reaction of the object to be treated that has sunk in the upper flow medium layer portion 11b proceeds at a relatively slow rate. As a result, it is possible to avoid a large amount of gaseous substances (particularly water vapor) being generated at once by a thermal reaction such as a combustion reaction.

The object to be treated that has undergone heat treatment such as drying in the upper flow medium layer portion 11b is settled in the lower flow medium layer portion 11c. In the lower flow medium layer portion 11c, the object to be treated is quickly subdivided by relatively violent contact with the flow medium particles and the flow gas.

As described above, in the present embodiment, the upper flow medium layer portion 11b is in a relatively gentle flow state, and the lower flow medium layer portion 11c is in a relatively intense flow state. As a result, for the undried object to be treated, a large amount of water vapor can be avoided by gently advancing the thermal reaction in the upper flow medium layer portion 11b, so that a rapid rise in temperature can be prevented and the temperature is gentle. The thermal reaction can be suitably maintained. On the other hand, with respect to the dried object to be processed, the object to be processed can be quickly refined by advancing a relatively intense thermal reaction (fast reaction rate) in the lower flow medium layer portion 11c. .. As a result, smooth and stable treatment can be performed by preventing flow obstruction and furnace blockage due to the unburned object to be treated.

As the combustion reaction of the object to be treated progresses, fine particles are generated after combustion. When the object to be treated contains incombustibles such as rubble and metal, impurities made of incombustibles and the like are left in the flow medium layer 11a as the combustion reaction of the object to be treated progresses. Since the contaminants have a heavy true specific density, they settle in the flow medium layer 11a. The contaminants that have settled to the bottom of the flow medium layer 11a are discharged to the outside of the furnace through the flow medium out-of-burner discharge pipe 14 by the operation of the out-of-fire flow medium discharge device 21 together with the surrounding flow media.

The contaminants and the fluid medium discharged to the outside of the furnace are sent to the contaminant classifier 22. The flow medium from which the contaminants have been separated by the contaminant classification device 22 is discharged from the fluid medium collection port 22a and conveyed by the fluid medium return device 23. The fluidized medium is returned into the furnace from the position of the freeboard portion 10 or the like above the fluidized bed layer 11a of the bubbling type fluidized bed reactor 1.

The separated contaminants are discharged to the outside from the contaminant classifier 22. After discharge, the contaminants are classified according to their respective materials through, for example, a separately provided sorter (magnetic separator or the like), and appropriate treatment is performed.

On the other hand, the post-combustion fine particles generated by the heat treatment of the object to be treated (excluding impurities) rise on the flowing gas (and / or the post-flow gas, exhaust gas) that rises through the flow medium layer 11a. .. After combustion, the fine particles pass through the bubbling fluidized bed interface and flow to the freeboard section 10. After combustion, the unburned components contained in the fine particles are secondarily burned by mixing with the secondary combustion gas supplied into the freeboard section 10. After combustion, the fine particles are conveyed on the exhaust gas in the freeboard section 10 and discharged from the bubbling type fluidized bed reactor 1 via the discharge port 10a. The post-combustion fine particles discharged from the bubbling type fluidized bed reactor 1 are supplied to the downstream treatment facility 6.

<Acquisition of Thermal Image> In the present embodiment, the bubbling type fluidized bed reactor 1 is provided with an infrared camera 3 as shown in FIG.

The infrared camera 3 acquires a thermal image in the furnace by detecting infrared rays radiated from an object in the furnace. The thermal image acquired by the infrared camera 3 is an image showing the temperature distribution in the furnace as seen from the viewpoint of the infrared camera 3. The viewpoint indicates a position where the infrared camera 3 which is a measuring instrument is arranged.

Further, the infrared camera 3 of the present embodiment acquires a thermal image in the furnace via the selective transmission filter 3a. The selective transmission filter 3a is a filter that selectively transmits light having a wavelength (for example, 3.9 μm band) that the flame does not emit.

Here, "the flame does not radiate" means that the luminous intensity is significantly lower (almost no irradiation) than the light of other wavelengths emitted by the flame, and the flame does not radiate the light of the wavelength at all. It does not indicate that.

By using the selective transmission filter 3a, a thermal image of an object on the other side of the flame can be obtained transparently. In the present embodiment, the selective transmission filter 3a is integrally configured with the infrared camera 3, but may be a separate body. That is, the selective transmission filter 3a may be arranged on the path through which the light in the furnace passes, and the transmitted light transmitted through the selective transmission filter 3a may be processed by a normal infrared camera.

As described above, by acquiring a thermal image showing the temperature distribution in the furnace through the infrared camera 3 and the selective transmission filter 3a, it is useful when the reaction is not accompanied by a luminescent flame and the inside of the furnace is pitch black. Even in the case of a reactor that performs heat treatment, which cannot acquire a clear visible optical image, it is possible to acquire a thermal image of an object in the depths of darkness.

A plurality (for example, two or more) infrared cameras 3 are provided for the purpose of creating a three-dimensional thermal image (an image showing the temperature distribution in three dimensions). The relative positions of the plurality of infrared cameras 3 are stored in advance by the control device 9.

It is desirable that each infrared camera 3 be installed at a position overlooking the entire interface of the fluidized bed that is bubbling. The infrared camera 3 can be installed at a position such as the ceiling surface of the bubbling type fluidized bed reactor 1 or the side wall surface of the freeboard portion 10. The infrared camera 3 needs to include the entire surface of the bubbling fluidized bed interface in the acquired image range. However, this does not apply when it is difficult to include the entire surface of the fluidized bed interface within the acquired image range due to restrictions on the installation of the infrared camera 3.

In the present embodiment, the control device 9 performs a known image composition process and creates a three-dimensional thermal image based on the thermal images acquired by the plurality of infrared cameras 3 (three-dimensional thermal image creation step). The control device 9 stores the created three-dimensional thermal image of the fluidized bed interface in association with one or a plurality of operating variables that affect the bubbling state in the fluidized bed corresponding to the thermal image. This instrumental variable includes, for example, the aeration amount of the flowing gas, the aeration point, the temperature of the flowing gas, the processing amount of the object to be treated, the filling amount of the flow medium, and the like.

Here, an image composition process for creating a three-dimensional thermal image based on the thermal images from the two infrared cameras 3 will be briefly described. First, a specific location of the bubbling fluidized bed interface identifies the position displayed in each of the two thermal images acquired by the two infrared cameras 3 at the same time. Then, using the respective arrangement positions and viewpoints of the two infrared cameras 3 stored in advance, the distance from each infrared camera 3 to the specific location of the bubbling fluid bed interface based on the trigonometry or the like. Is calculated. Based on each of the distances from each infrared camera 3 to the specific location, the three-dimensional coordinates of the specific location can be obtained. By processing in this way, the control device 9 creates a three-dimensional thermal image while specifying the three-dimensional coordinates of each part of the fluidized bed interface that is bubbling.

<Control performed by the control device> The control device 9 of the present embodiment flows in the bubbling type flow bed type reactor 1 based on a three-dimensional thermal image created by using the thermal image acquired by the infrared camera 3. The average height of the floor interface is monitored, and if necessary, the filling amount of the flow medium in the flow medium layer 11a is increased or decreased so as to maintain the average height of the fluid bed interface within an appropriate range. The filling amount of the flow medium in the flow medium layer 11a can be increased or decreased manually or automatically as described above.

First, the control device 9 creates and stores a three-dimensional thermal image from the thermal images acquired by the two infrared cameras 3. The created 3D thermal image is stored in association with instrumental variables that affect the bubbling state in the fluidized bed. Specifically, in the present embodiment, as shown in FIG. 3, a plurality of division units M1 are defined by dividing the fluidized bed interface so as to form a mesh in a plan view. The three-dimensional thermal image is stored in a state associated with an instrumental variable that affects the bubbling state of the fluidized bed portion corresponding to the plurality of division units M1.

Then, the control device 9 calculates the surface average height of the fluidized bed interface in each division unit M1 of the fluidized bed interface based on the three-dimensional thermal image (unit fluidized bed interface height calculation step). The average height here means the local average value in the mesh with respect to the height of the fluidized bed interface when paying attention to one mesh. The control device 9 stores each of the calculated surface average heights of the divided units M1 in association with the manipulated variables that affect the bubbling state in the fluidized bed corresponding to each divided unit (unit fluidized bed interface). Height memory process).

Next, the control device 9 increases or decreases the filling amount of the fluidized medium so as to maintain the average height of the fluidized bed interface within an appropriate range based on the calculated surface average height of each division unit M1. To control. When the filling amount of the flow medium is manually increased or decreased, the control device 9 informs the operator, for example, by displaying the change amount to be increased or decreased in the filling amount of the flow medium on the display device shown in the figure. When the filling amount of the flow medium is automatically increased or decreased, the control device 9 operates, for example, a flow medium transfer device (not shown) or a related device such as the flow medium out-of-furnace discharge device 21 to operate the furnace. A flow medium is supplied into the furnace from a flow medium storage unit (not shown) provided outside, or a part of the flow medium in the furnace is discharged from the furnace so as to be stored in the flow medium storage device.

As shown in FIG. 1, the thickness of the upper flow medium layer portion 11b changes as the filling amount of the flow medium increases or decreases. Even if the aeration amount and the flow velocity of the flow gas are the same, the movement of the flow medium in the upper flow medium layer portion 11b becomes slow due to the increase in the thickness of the upper flow medium layer portion 11b. On the other hand, as the thickness of the upper flow medium layer portion 11b becomes thin, the movement of the flow medium in the upper flow medium layer portion 11b becomes relatively fast.

In other words, the flow state in the upper flow medium layer portion 11b can be adjusted by changing the filling amount of the flow medium (that is, the thickness of the upper flow medium layer portion 11b). Utilizing this, the rate (reactivity) of the thermal reaction generated in the upper flow medium layer portion 11b can be adjusted.

As a result, even when objects to be processed having various properties are put into the bubbling type fluidized bed reactor 1, it is possible to avoid a violent thermal reaction from occurring in a short time. That is, the influence of the properties of the object to be treated on the bubbling state of the fluidized bed can be appropriately smoothed, and the bubbling state of the fluidized bed can be satisfactorily stabilized.

The control device 9 of the present embodiment further executes a method for stabilizing the fluidized bed bubbling state in order to stabilize the bubbling state in the fluidized bed. Thereby, while monitoring the bubbling state in the fluidized bed, it is possible to give an instruction to adjust the filling amount of the fluidized bed as necessary to stabilize the bubbling state in the fluidized bed.

Specifically, the control device 9 calculates the surface average temperature for each of the plurality of division units M1 shown in FIG. 3 based on the three-dimensional thermal image created as described above (unit fluidized bed interface). Average temperature calculation process). The control device 9 stores each of the calculated surface average temperatures of the divided units M1 in association with the manipulated variables that affect the bubbling state in the fluidized bed corresponding to each divided unit (unit fluidized bed interface average). Temperature memory process).

Then, the control device 9 is a peripheral division unit in which the same operating variable as the surface average temperature of the division unit M1 stored as described above is given to the division unit M1 to be determined. The surface average temperature of the division unit is compared, and the position reference temperature deviation, which is the deviation from the peripheral division unit, is calculated and stored (temperature deviation calculation step).

By the way, as described above, the fluidized gas supplied from the fluidized gas supply unit 12 into the furnace rises in the fluidized bed while being in contact with the fluidized medium in the fluidized state and the object to be treated. It passes through the fluidized bed interface and flows to the freeboard section 10. In the process of ascending in the fluidized bed, the fluidized gas heats the fluidized medium and the object to be treated mainly by contact heat transfer by contact with the fluidized medium and the object to be treated. Here, depending on the form of the thermal reaction in the furnace, a chemical reaction (thermal reaction) accompanied by various exothermic reactions may occur in addition to the above-mentioned physical heat exchange while the flowing gas is rising in the fluidized bed. As it progresses, the flow medium, the object to be treated, and the flow gas in the flow bed may be heated respectively. The numerical value of the surface temperature of the flow medium layer 11a for each division unit M1 indicates the result of the flow medium being heated in the flow medium layer 11a below the surface layer in the division unit.

In that sense, the position-referenced temperature divergence, which is an index indicating the local temperature divergence when viewed over the entire surface of the flow medium layer 11a, is the flow under the surface layer of the flow medium layer 11a portion corresponding to the division unit M1. It shows how much the heated state in the medium layer 11a deviates from the heated state in the other dividing units. Therefore, the position reference temperature divergence causes some divergence or a peculiar situation with respect to the "flow state" in the flow medium layer 11a under the surface layer of the division unit M1 as compared with the surrounding division unit M1. Indicates whether or not.

Further, in the temperature deviation calculation step, the control device 9 has the same operating variable as the surface average temperature of the division unit M1 to be determined, in addition to the position reference temperature deviation which is the deviation from the surface average temperature of the peripheral division unit. The time that is the deviation from the historical value by comparing with the historical value of the surface average temperature of the division unit M1 itself in the normal time when it is given and the bubbling state does not have a deviation or a peculiar situation. The reference temperature deviation is calculated.

By the way, the time-based temperature deviation, which is an index showing the deviation from the past temperature history when viewed in the same division unit M1, is the flow medium layer 11a below the surface layer of the flow medium layer 11a portion corresponding to the division unit M1. In the above, it is shown whether or not there is some kind of divergence or peculiar situation different from before regarding the "flow state".

Further, as described above, the control device 9 is a position reference height deviation which is a deviation between the average height calculated for each division unit M1 and the average height of the peripheral division units thereof, and / or each division. Each of the time-based height divergence, which is the divergence between the average height calculated for the unit M1 and the past average height (average height history) of the division unit M1 itself, is calculated (height divergence calculation step). ).

By the way, the average height of the division unit M1 is such that in the division unit M1, the flow gas lifts the flow medium in the flow medium layer 11a under the surface layer by the effect of pushing the flow medium away, and this portion of the flow medium layer 11a. It is a height showing the result of lowering the bulk specific gravity as a whole (for example, bulk specific gravity 1.5 t / m ³ → 1.0 t / m ^3).

In this sense, the position reference height deviation is such that the fluid medium reduces the bulk specific density in the fluid medium layer 11a under the surface layer of the corresponding division unit M1 to the extent that the fluid medium reduces the bulk specific density in the peripheral division unit. On the other hand, it shows the degree of divergence. That is, the position reference height divergence causes some divergence or a peculiar situation with respect to the bubbling state (flow state) in the flow medium layer 11a under the surface layer of the corresponding division unit M1 as compared with the surrounding division unit M1. Indicates whether or not it is.

The time-based height divergence is a divergence or a specific situation different from the previous one with respect to the bubbling state (flow state) in the flow medium layer 11a under the surface layer of the division unit M1 when viewed in the same division unit M1. Indicates whether or not is occurring.

In the dissociation division unit specifying step, the control device 9 calculates and stores the division unit M1 to be determined as described above, and the position reference temperature deviation and the time reference temperature deviation, and the position reference. Evaluate the height divergence and the time-based height divergence. In the following, the dissociation mentioned here may be simply referred to as "four dissociation indexes". As a result of comprehensively evaluating the four divergence indexes, if the divergence is large, the control device 9 determines that the bubbling state in the corresponding fluidized bed is unstable, and specifies the division unit M1 as the divergence division unit. do.

The control device 9 needs to change the manipulated variable to reduce the overall divergence of the split unit M1 based on the history of the manipulated variable related to the split unit M1 with respect to the specified divergence split unit. Judgment about. Further, when the control device 9 determines that the instrumental variable needs to be changed, the position where the divergence or a specific situation occurs due to the divergence of the divergence division unit (that is, the upper flow medium layer portion 11b or the lower flow medium layer portion 11c). ), Dissociation characteristics (temperature divergence degree, height divergence degree, etc.), and the distribution of the divergence division units when there are multiple divergence division units, etc. Countermeasure method) is decided.

This countermeasure is, for example, (1) temporarily changing the air flow rate of the fluidized gas to the fluidized bed portion corresponding to the specified division unit M1, (2) changing the heating temperature of the fluidized gas, and so on. Temporarily change the temperature of the fluidized bed layer 11a of the fluidized bed portion corresponding to the specified division unit M1 by changing the external heating amount, etc., and (3) change the processing amount (input amount) of the object to be processed. (4) Changing the filling amount of the fluidized medium in the fluidized bed layer 11a and the like can be mentioned.

The control device 9 changes the instrumental variables based on the countermeasure method determined as described above, and controls the operation of the bubbling type fluidized bed reactor 1 (bubbling state stabilization step). As a result, the control device 9 more accurately grasps the bubbling state in the fluidized bed in the furnace by using the three-dimensional thermal image created based on the thermal image acquired through the infrared camera 3 or the like. If it is determined that the bubbling state in the fluidized bed is unstable, the bubbling state in the fluidized bed will be stabilized by implementing appropriate countermeasures.

Further, in the control device 9, with respect to the dissociation division unit specified as described above, whether the dissociation in the dissociation division unit is due to the dissociation occurring in the upper flow medium layer portion 11b or a specific situation. Alternatively, it is determined whether it is due to a divergence or a specific situation occurring in the lower flow medium layer portion 11c (that is, the site where the event causing the divergence occurs).

The site where the causal event of the divergence occurs can be estimated by comprehensively considering the four divergence indexes in the divergence division unit or the four divergence indexes in the surrounding division units.

Generally, for example, when the cause of the dissociation exists at a position deep from the surface layer, it takes time for the influence of the dissociation to reach the interface, and the influence occurs over a wide range of the interface. On the other hand, when the cause of the dissociation exists at a position shallow from the surface layer, the influence of the dissociation reaches the interface in a short time, and the range affected by the interface becomes narrow. Therefore, it is possible to estimate the occurrence site of the causal event of the dissociation by analyzing the four dissociation indexes for each division unit.

The strength of the degree of the phenomenon that occurs at the interface due to the dissociation that occurs inside the fluidized bed layer 11a is the operating experience of the bubbling type fluidized bed reactor 1, the furnace shape, the amount of the fluidized medium, and the properties of the fluidized medium (for example, with the fluidized bed). It can change according to various related factors such as the difference between these substances, changes in properties over time, etc.), properties of the object to be treated, gas temperature for flow, temperature in the fluidized bed, and the like. In addition, these phenomena (or changes in the phenomena) may affect the above-mentioned various related factors. Therefore, in the bubbling type fluidized bed reactor 1, the criteria for determining the occurrence site of the causal event of the dissociation are set in advance so as to match the peculiar properties of the designed and constructed reactor. It can also be adjusted according to the actual operating conditions of the reactor.

When it is determined that the divergence of the specified divergence division unit is due to the divergence occurring in the upper flow medium layer portion 11b or a specific situation, the control device 9 is subjected to the above-mentioned bubbling state stabilization step. In, an instruction to change the thickness of the flow medium layer 11a is output. The filling amount of the flow medium filled in the furnace bottom is adjusted (increased or decreased) based on the instruction of the control device 9. Since the change in the thickness of the flow medium layer 11a means the change in the thickness of the upper flow medium layer portion 11b, it can be expected that the causal event will be surely eliminated.

As described above, in the control device 9 of the present embodiment, when the above temperature divergence and / or height divergence occurs in a part of the fluidized bed interface for some reason, the divergence occurs according to the actual condition of the fluidized bed interface. By implementing measures based on the history of instrumental variables related to the generated part, the deviation can be quickly suppressed. Further, when the control device 9 determines that the site where the cause event of the dissociation occurs is the upper flow medium layer portion 11b, the control device 9 adjusts the thickness of the upper flow medium layer portion 11b, so that the cause event of the dissociation occurs again. It can be prevented so that it does not occur.

The method for stabilizing the bubbling state in the fluidized bed can be changed as follows, for example. Specifically, the control device 9 has, in addition to the position-referenced temperature divergence and the time-based temperature divergence, the position-referenced height divergence and the time-based height divergence, with respect to the division unit M1 to be determined, as described above. Based on the three-dimensional thermal image, the intensity of the dynamics of the fluidized bed interface corresponding to the division unit M1 is analyzed.

The control device 9 has the intensity of the dynamics of the fluidized bed interface corresponding to the division unit M1 of the determination target obtained by analyzing the three-dimensional thermal image and the (average) intensity of the dynamics of the entire fluidized bed interface. , And acquire and store the unit dynamic divergence, which is the divergence (dynamic divergence acquisition process).

Further, the control device 9 corresponds to the intensity of the dynamics of the fluidized bed interface corresponding to the division unit M1 of the determination target obtained by analyzing the three-dimensional thermal image in the dynamic deviation acquisition step and the division unit M1. The intensity of the past dynamics of the fluidized bed is compared, and the time-based dynamic deviation, which is the deviation, is acquired and stored.

In the divergence division unit specifying step, the control device 9 uses six indexes, which are the unit dynamic divergence and the time-based dynamic divergence, in addition to the above four indexes, with respect to the division unit M1 to be determined, and is in a bubbling state. Evaluate the divergence. In the following, the dissociation mentioned here may be simply referred to as "six dissociation indexes". As a result of comprehensively evaluating the six divergence indexes, if the divergence is large, the division unit M1 is specified as the divergence division unit.

The control device 9 determines whether or not it is necessary to change the manipulated variable in order to reduce the deviation of the bubbling state in the split unit M1 based on the history of the manipulated variable related to the split unit M1. When it is determined that the instrumental variable needs to be changed, the control device 9 determines the position where the divergence or a specific situation occurs due to the divergence of the divergence division unit (that is, the upper flow medium layer portion 11b or the lower flow medium layer portion 11c). ), Dissociation characteristics (temperature divergence degree, height divergence degree, dynamic divergence degree, etc.), and the instrumental variables to be changed and their changes based on the distribution of the divergence division units when there are multiple divergence division units. Determine the amount (ie, countermeasures).

The control device 9 changes each of the instrumental variables that need to be changed based on the countermeasure method determined in the countermeasure method determination step so as to stabilize the bubbling state in the corresponding fluidized bed, and the bubbling type flow. Control the operation of the bed-type reactor 1.

Further, the control device 9 has a divergence or a specific situation in which the divergence in the divergence division unit is generated in the upper flow medium layer portion 11b with respect to the divergence division unit specified as described above. It is determined whether the cause is a dissociation or a specific situation occurring in the lower flow medium layer portion 11c. This determination is also made using the six deviation indicators.

When it is determined that the divergence of the specified divergence division unit is due to the divergence occurring in the upper flow medium layer portion 11b or a specific situation, the control device 9 sets the flow medium layer 11a (and thus, the flow medium layer 11a). An instruction to change the thickness of the upper flow medium layer portion 11b) is output.

As described above, when the bubbling state in the fluidized bed can be suitably grasped by using the method for stabilizing the bubbling state in the fluidized bed of the present embodiment and a deviation in the fluidized state in the fluidized bed occurs, By implementing appropriate countermeasures, the divergence can be converged and the bubbling state in the fluidized bed can be stabilized.

Further, when the control device 9 of the present embodiment determines that the site where the cause event of the dissociation occurs is the upper flow medium layer portion 11b, the control device 9 adjusts the thickness of the upper flow medium layer portion 11b to cause the dissociation cause event. Can be prevented from occurring again.

As described above, in the bubbling type fluidized bed type reactor 1 of the present embodiment, the fluidized bed is made to flow by blowing a fluidized gas from the bottom of the furnace into a fluidized medium filled in the lower part of the furnace. A floor is formed, and at least one of drying, thermal decomposition, and combustion is heat-treated on the object to be treated. The bubbling type fluidized bed reactor 1 includes a plurality of infrared cameras 3 and a control device 9. The plurality of infrared cameras 3 are provided at a position overlooking from the upper portion or the lateral upper portion of the fluidized floor interface, which is the upper interface of the fluidized bed, and are via a selective transmission filter 3a that selectively transmits light having a wavelength that is not emitted by a flame. The thermal image is acquired from different viewpoints with respect to the fluidized bed interface. The control device 9 creates a three-dimensional thermal image for the fluidized bed interface based on the thermal images acquired by the plurality of infrared cameras 3. The fluidized bed is composed of an upper fluidized bed layer 11b and a lower fluidized bed 11c arranged in the thickness direction, and the cross-sectional area of the upper fluidized bed 11b is 1. It is more than four times. The control device 9 increases or decreases the thickness of the fluidized bed (fluidized bed layer 11a) in the furnace based on the created three-dimensional thermal image.

As a result, by providing the fluidized medium layer 11a with two types of fluidized beds in the thickness direction, it is possible to promote the fluidized bed to have substantially the same fluidized state on the entire surface of the interface. Therefore, the fluidized state of the entire surface of the fluidized bed interface can be moderated, and the formation of locally different fluidized beds can be avoided. Further, by making the fluidized state on the interface side of the fluidized bed gentle, the thermal reaction can proceed while suppressing the reactivity (speed of reaction) in the initial stage of the heat treatment for the object to be treated. As a result, it is possible to avoid a rapid rise in temperature and a rapid increase in the amount of gaseous substances generated.

Further, in the bubbling type fluidized bed reactor 1 of the present embodiment, the control device 9 divides the created three-dimensional thermal image into a plurality of division units M1 formed by dividing the fluidized bed interface into a mesh shape in advance. Store in association with operational variables that affect the bubbling state of the corresponding fluidized bed interface. The control device 9 calculates and stores the unit fluidized bed interface height, which is the average height of the fluidized bed interface in the divided unit M1, for each of the plurality of divided units M1 based on the created three-dimensional thermal image. The control device 9 increases or decreases the thickness of the upper fluidized bed layer portion 11b in the furnace so as to maintain the height of the fluidized bed interface within an appropriate range based on the calculated unit fluidized bed interface height.

As a result, by appropriately adjusting the flow state of the upper fluidized bed layer portion 11b, the height of the fluidized bed interface is maintained within an appropriate range, and the reactivity (speed of reaction) is maintained in the initial stage of heat treatment of the object to be treated. ) Can be maintained properly.

Further, the fluidized bed bubbling state stabilization method used in the bubbling type fluidized bed reactor 1 of the present embodiment includes a unit fluidized bed interface average temperature calculation step, a unit fluidized bed interface average temperature storage step, and a temperature divergence calculation step. It includes a unit fluidized bed interface height calculation step, a unit fluidized bed interface height storage step, a height divergence calculation step, a divergence division unit identification step, and a bubbling state stabilization step. In the unit fluidized bed interface average temperature calculation step, the control device 9 divides the fluidized bed interface into a mesh shape in advance based on the created three-dimensional thermal image, so that each of the plurality of division units M1 is formed. The unit fluidized bed interface average temperature, which is the average temperature of the fluidized bed interface in the divided unit M1, is calculated. In the unit fluidized bed interface average temperature storage step, the control device 9 uses the average temperature calculated in the unit fluidized bed interface average temperature calculation step as an operating variable that affects the bubbling state of the fluidized bed interface corresponding to the division unit M1. Remember in association with. In the temperature divergence calculation step, the control device 9 sets the average temperature of each division unit M1 and the average temperature in the peripheral division unit M1 around each division unit M1 for each of the plurality of division units M1. , And / or the time-based temperature divergence, which is the divergence between the average temperature of the division unit M1 and the past average temperature in the same division unit M1, is calculated. In the unit fluidized bed interface height calculation step, the control device 9 calculates the unit fluidized bed interface height, which is the average height of the fluidized bed interface in the divided unit M1, for each of the plurality of divided units M1. In the unit fluidized bed interface height storage step, the control device 9 uses the average height calculated in the unit fluidized bed interface height calculation step as an operating variable that affects the bubbling state of the fluidized bed interface corresponding to the division unit. Remember in association with. In the height divergence calculation step, the control device 9 determines the average height of each division unit M1 and the average height in the peripheral division unit M1 which is the peripheral division unit M1 of each division unit M1 for each of the plurality of division units M1. Calculate the time-based height divergence, which is the divergence between the position-based height divergence, which is the divergence between the and, and / or the average surface height of the division unit M1 and the past average height in the same division unit M1. .. In the divergence division unit specifying step, the control device 9 calculates the position reference temperature divergence and / or the time reference temperature divergence calculated in the temperature divergence calculation step and the height divergence calculation step for each of the division units. The position reference height divergence and / or the time reference height divergence are evaluated, and the division unit M1 having a large divergence in total is specified as the divergence division unit. In the bubbling state stabilization step, the control device 9 adjusts to converge the divergence in the divergence division unit based on the operation history of the instrumental variables affecting the part of the fluidized bed interface corresponding to the divergence division unit. The required instrumental variables are determined, and the determined instrumental variables are adjusted. In the bubbling state stabilization step, the control device 9 performs the position reference temperature divergence, the time reference temperature divergence, the position reference height divergence, and the time reference height divergence of the divergence division unit, and the division around the divergence division unit. Based on the unit position-based temperature divergence, time-based temperature divergence, position-based height divergence, and time-based height divergence, the divergence in the divergence division unit is among the upper flow medium layer section 11b and the lower flow medium layer section 11c. Determine which internal event is the cause. In the bubbling state stabilization step, when it is determined that the divergence in the divergence division unit is due to an internal event of the upper fluidized bed layer portion 11b, the control device 9 issues an instruction to change the thickness of the fluidized bed.

As a result, by analyzing the temperature and height of each division unit M1 of the fluidized bed interface, the bubbling state of the fluidized bed can be accurately grasped, and measures for stabilizing the bubbling state can be determined more accurately. can. As a result, the dissociation can be quickly converged by appropriate measures, and the thickness of the upper flow medium layer portion 11b is adjusted to prevent the dissociation due to the internal event of the upper flow medium layer portion 11b from occurring again. be able to.

In addition, the fluidized bed bubbling state stabilization method includes a dynamic deviation acquisition step. In the dynamic divergence acquisition step, a plurality of division units M1 formed by the control device 9 dividing the fluidized bed interface into a mesh shape in advance based on the created three-dimensional thermal image and the historical three-dimensional thermal image. By acquiring and analyzing the fluidized bed dynamics, which is the dynamics of the fluidized state in the divided unit M1, the difference between the fluidized bed dynamics of each divided unit M1 and the fluidized bed dynamics of the entire fluidized bed interface is obtained. The time-based dynamic divergence, which is the divergence between the unit dynamic divergence and / or the fluidized bed dynamics of the division unit M1 and the past fluidized bed dynamics in the same division unit M1, is acquired. In the divergence division unit specifying step, the control device 9 has the position-referenced temperature divergence and / or the time-based temperature divergence calculated in the temperature divergence calculation step and the position-referenced height divergence and / or the position-referenced height divergence calculated in the height divergence calculation step. Comprehensively evaluate the time-based height divergence and the unit dynamic divergence and / or the time-based dynamic divergence acquired in the dynamic divergence acquisition process, and specify the division unit M1 having a large divergence as the divergence division unit. do. In the bubbling state stabilization step, the control device 9 is adjusted to converge the divergence in the divergence division unit based on the operation history of the instrumental variables affecting the part of the fluidized bed interface corresponding to the divergence division unit. Determine the required manipulated variables and adjust the determined manipulated variables. In the bubbling state stabilization step, the control device 9 has the position reference temperature divergence, the time reference temperature divergence, the position reference height divergence, the time reference height divergence, and the unit dynamic divergence of the divergence division unit specified in the divergence division unit identification step. , And the time-based dynamic divergence, and the position-based temperature divergence, the time-based temperature divergence, the position-based height divergence, the time-based height divergence, the unit dynamic divergence, and the time-based dynamic divergence of the peripheral division unit of the divergence division unit. Based on this, it is determined which of the internal events of the upper flow medium layer portion 11b and the lower flow medium layer portion 11c causes the divergence in the divergence division unit. In the bubbling state stabilization step, when it is determined that the divergence in the divergence division unit is due to an internal event of the upper fluidized bed layer portion 11b, the control device 9 issues an instruction to change the thickness of the fluidized bed.

This makes it possible to comprehensively determine the bubbling state of the fluidized bed based on the temperature and height of the fluidized bed interface and the intensity of the fluidized bed, and more accurately determine the location where the fluidized bed is locally intense. Therefore, it is possible to more accurately determine the measures for converging the divergence.

Although the preferred embodiment of the present invention has been described above, the above configuration can be changed as follows, for example.

As the flow dynamics, for example, the amount of change in the unit time of the fluidized bed interface in the division unit M1 can be used. However, it is not limited to this.

The infrared cameras 3 may be provided at different heights. That is, a part of the infrared cameras 3 may be provided at the top of the bubbling type fluidized bed type reactor 1, and a part of the infrared cameras 3 may be provided near the side wall of the freeboard part 10.

The infrared camera 3 may be separately provided on the side surface of the fluidized bed portion 11. In this case, since the thermal image of the side surface of the fluidized bed portion 11 can be acquired, there is room for estimating the temperature divergence in the fluidized bed.

The flow medium layer 11a may be composed of three flow medium layer portions having different intensities of flow state. In this case, in the method of thickening the flow medium layer 11a, it is preferable that the intensity of the flow state gradually decreases from the top to the bottom.

The object to be treated may be put into the furnace after being dried or heated to some extent by the heat of the exhaust gas generated in the bubbling type fluidized bed reactor 1.

The average height of the fluidized bed interface may be an absolute height with respect to a predetermined position such as the bottom of the furnace, or may be a relative height with respect to the average height of the entire fluidized bed interface.

The division unit M1 is not limited to the quadrangle, and may have other shapes. The shapes and sizes of the division units M1 may be different from each other.

1 Bubbling type fluidized bed reactor 10 Free board part 10a Discharge port 10b Input port 10c Air supply port for secondary combustion 11 Fluidized bed 11a Fluidized bed layer 11b Upper fluidized bed layer (upper fluidized bed)
11c Lower fluidized bed layer (lower fluidized bed)
12 Flowing gas supply unit 13 Flowing gas supply main pipe 14 Flow medium out-of-furnace discharge pipe 21 Flow medium out-of-furnace discharge device 22 Contamination classifier 22a Flow medium recovery port 23 Flow medium return device 24 Dust supply device 3 Infrared camera 3a Selective permeation filter 4 Gas supply unit 41 Flow gas supply device 42 Secondary combustion gas supply device 5 Gas warmer 6 Downstream processing equipment

Claims (3)

By blowing a fluidized gas from the bottom of the furnace into the fluidized medium filled in the lower part of the furnace, the fluidized bed is made to flow to form a fluidized bed, and the object to be treated is dried, thermally decomposed, or burned at least. A bubbling type fluidized bed reactor that performs either heat treatment.
The fluid bed interface is provided at a position overlooking from the upper or lateral upper interface of the fluid bed interface, which is the upper interface of the fluid bed, and is provided at the fluid bed interface via a selective transmission filter that selectively transmits light having a wavelength not emitted by a flame. On the other hand, with multiple infrared cameras that acquire thermal images from different viewpoints,
A control device that creates a three-dimensional thermal image for the fluidized bed interface based on the thermal images acquired by the plurality of infrared cameras.
With
The fluidized bed is composed of an upper fluidized bed and a lower fluidized bed arranged in the thickness direction, and the cross-sectional area when the upper fluidized bed is cut by a horizontal plane is horizontal to the lower fluidized bed. It is more than 1.4 times the cross-sectional area when cut on a flat surface.
The fluidized gas is supplied to the lower fluidized bed,
The control device increases or decreases the thickness of the fluidized bed in the furnace based on the created three-dimensional thermal image .
The control device is
The created three-dimensional thermal image is stored in association with an operating variable that affects the bubbling state of the fluidized bed interface corresponding to a plurality of division units formed by preliminarily dividing the fluidized bed interface into a mesh shape. ,
Based on the created three-dimensional thermal image, the unit fluidized bed interface height, which is the average height of the fluidized bed interface in the divided unit, is calculated and stored for each of the plurality of divided units.
A bubbling type characterized in that the thickness of the upper fluidized bed in the furnace is increased or decreased so as to maintain the height of the fluidized bed interface within an appropriate range based on the calculated unit fluidized bed interface height. Fluidized bed reactor. A method for stabilizing a fluidized bed bubbling state used in the bubbling type fluidized bed reactor according to claim 1.
Based on the three-dimensional thermal image created by the control device, the fluidized bed interface is averaged in each of the plurality of division units formed by dividing the fluidized bed interface into a mesh shape in advance. The unit fluidized bed interface average temperature calculation process for calculating the unit fluidized bed interface average temperature, which is the temperature,
The control device stores the unit fluidized bed interface average temperature calculated in the unit fluidized bed interface average temperature calculation step in association with an operating variable that affects the bubbling state of the fluidized bed interface corresponding to the division unit. Unit fluidized bed interface average temperature storage process and
For each of the plurality of division units, the control device has the unit fluidized bed interface average temperature of each division unit and the unit fluidized bed in the peripheral division unit which is the division unit around each division unit. Position reference temperature divergence, which is a divergence from the interface average temperature, and / or the divergence between the unit fluidized bed interface average temperature of the division unit and the past unit fluidized bed interface average temperature in the same division unit. The temperature divergence calculation process for calculating the time-based temperature divergence, which is
A unit fluidized bed interface height calculation step in which the control device calculates the unit fluidized bed interface height, which is the average height of the fluidized bed interface in the divided unit, for each of the plurality of divided units.
The control device associates the unit fluidized bed interface height calculated in the unit fluidized bed interface height calculation step with the operating variable that affects the bubbling state of the fluidized bed interface corresponding to the division unit. Unit to be memorized Fluid bed interface height memorization process and
For each of the plurality of division units, the control device has the unit fluidized bed interface height of each division unit and the unit fluidized bed interface in the peripheral division unit which is the division unit around each division unit. Position-based height divergence, which is a divergence from the height, and / or time, which is the divergence between the unit fluidized bed interface height of the division unit and the past unit fluidized bed interface height in the same division unit. The height deviation calculation process for calculating the reference height deviation and
The control device has the position reference temperature divergence and / or the time reference temperature divergence calculated in the temperature divergence calculation step and the position reference calculated in the height divergence calculation step for each of the division units. A divergence division unit specifying process that evaluates the height divergence and / or the time-based height divergence and specifies the division unit having a large divergence as the divergence division unit.
The operation that requires adjustment in order for the control device to converge the divergence in the divergence division unit based on the operation history of the operation variable that affects the portion of the fluidized bed interface corresponding to the divergence division unit. The variables are determined, the determined operation variables are adjusted, and the position-referenced temperature divergence, the time-referenced temperature divergence, the position-referenced height divergence, and the time-referenced height divergence of the divergence division unit, and the above-mentioned Based on the position reference temperature divergence, the time reference temperature divergence, the position reference height divergence, and the time reference height divergence of the division unit around the divergence division unit, the divergence in the divergence division unit is the said. When it is determined which of the internal events of the upper fluidized bed and the lower fluidized bed is caused, and it is determined that the divergence in the divergence division unit is due to the internal event of the upper fluidized bed, the thickness of the fluidized bed. Bubbling state stabilization process and giving instructions to change
A method for stabilizing a fluidized bed bubbling state, which comprises. The method for stabilizing a fluidized bed bubbling state according to claim 2.
Based on the three-dimensional thermal image created and the three-dimensional thermal image of the history, the control device divides the fluidized bed interface into a mesh shape in advance for each of the plurality of division units. By acquiring and analyzing the fluidized bed dynamics, which is the dynamics of the fluidized bed at the fluidized bed interface of the divided unit, the fluidized bed dynamics of each of the divided units and the fluidized bed dynamics of the entire fluidized bed interface can be obtained. A dynamic divergence acquisition step of acquiring a time-based dynamic divergence which is a divergence between the unit dynamic divergence which is a divergence and / or the fluidized bed dynamic of the division unit and the past fluidized bed dynamic in the same division unit. Including
In the divergence division unit specifying step, the control device calculates the height divergence with the position reference temperature divergence and / or the time reference temperature divergence calculated in the temperature divergence calculation step for each of the division units. Comprehensive evaluation of the position-based height divergence and / or the time-based height divergence calculated in the process and the unit dynamic divergence and / or the time-based dynamic divergence acquired in the dynamic divergence acquisition process. Then, the division unit having a large divergence overall is specified as the divergence division unit.
In the bubbling state stabilization step,
The operation that requires adjustment in order for the control device to converge the divergence in the divergence division unit based on the operation history of the operation variable that affects the portion of the fluidized bed interface corresponding to the divergence division unit. Determine the variable, adjust the determined instrumental variable, and
The control device has the position reference temperature divergence, the time reference temperature divergence, the position reference height divergence, the time reference height divergence, the unit dynamic divergence, and the time reference dynamic divergence of the divergence division unit. Based on the position reference temperature divergence, the time reference temperature divergence, the position reference height divergence, the time reference height divergence, the unit dynamic divergence, and the time reference dynamic divergence of the division unit around the divergence division unit. Therefore, it is determined whether the divergence in the divergence division unit is due to an internal event of the upper flow bed or the lower flow bed.
When it is determined that the divergence in the divergence division unit is due to an internal event of the upper fluidized bed, the control device issues an instruction to change the thickness of the fluidized bed. How to make it.

Images