JP2918138B2 - Vibrating fluidized bed equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating fluidized bed apparatus,
Effectively prevent short path of particles, do not mix undried or unreacted particles in product particles, perform efficient drying or decomposition reaction, and optimize particle movement speed and equipment slenderness ratio regardless of equipment capacity The present invention relates to a vibrating fluidized bed device such as a vibrating fluidized bed drying device or a vibrating fluidized bed decomposing device capable of maintaining the above conditions.

[0002]

2. Description of the Related Art A vibrating fluidized bed drying apparatus as a vibrating fluidized bed apparatus fluidizes and granulates particles in a fluidized chamber by vibration and moves the particles from a supply port to a discharge port of the granular material. The powder is dried by heat exchange with a heat source such as a gas. Such a oscillating fluidized bed dryer has no fountain-like particles scattered on the surface of the fluidized bed as in a bubble fluidized bed. There is an advantage that drying unevenness hardly occurs and uniform drying becomes possible. Further, since the amount of the fluidizing gas may be small or zero as compared with the bubble fluidized bed, it is suitable for fluidization of 100 μm or less in which power can be reduced and cohesiveness is strong. As described above, the vibrating fluidized bed apparatus is suitable for uniformly fluidizing coherent fine particles and wet particles, promoting heat transfer, and performing efficient drying and decomposition reactions.

[0003] As such a vibrating fluidized bed apparatus, for example, there is a vibrating fluidized bed drying apparatus as disclosed in JP-A-56-133577. In this drying apparatus, partitions are formed at regular intervals with partitions that open alternately in the upper and lower directions in the flow direction of the particles, and the particles pass through the respective compartments alternately through openings below and above the partitions to dry. This method is intended to prevent mixing of the particles before and after the partition wall, thereby preventing a short path of the particles.

[0004]

However, the vibrating fluidized bed dryer disclosed in the above publication has a one-way flow from the inlet to the outlet of the particles. And the amount of heat radiation (heat loss) increases,
Equipment costs also increase. Further, when the width is widened, the moving speed of the particles becomes slow, and as described in the above-mentioned publication, partitions are formed at regular intervals with partitions that open alternately in the upper and lower directions in the flow direction of the particles. However, it is inevitable that the mixing of particles progresses and a short path occurs even if a method is adopted in which the particles are alternately passed through each compartment and dried. In addition, it is difficult to maintain the optimum particle movement speed and the slenderness ratio of the device according to the device capability in such a one-way flow.

In the case of a vibrating fluidized bed, in order to obtain a stable fluidized state, it is preferable to maintain a predetermined shallow depth such as a depth of the fluidized bed of, for example, about 100 mm.
In order to increase the processing amount, there is a problem that the layer area becomes large. Furthermore, in a drying apparatus or a thermal decomposition apparatus, the temperature of the heating source may not be able to be increased due to constraints for maintaining the quality of the processed product. In this case, it is necessary to increase the heat transfer area. This also increases the layer area. For example, in the case of a drying apparatus as a vibrating fluidized bed apparatus, the temperature of the heating source cannot be set high due to constraints on the processing object, for example, restrictions such as not allowing crystallization water (internal water) of the processing object to fly. In some cases, the difference becomes smaller, the heat transfer area becomes larger, and the layer area becomes larger.

The present invention has been made in view of such a problem, and effectively prevents a short path of particles so that undried or unreacted particles are not mixed. It is an object of the present invention to obtain a vibrating fluidized bed device capable of maintaining a moving speed and a slender ratio of the device.

[0007]

In order to achieve the above object, a vibrating fluidized bed apparatus according to the present invention is characterized in that a fluidizing chamber is vibrated by a vibration generating device to fluidize the granular material, and the granular material is fluidized. In a vibrating fluidized bed apparatus which flows from a supply port on one end side to a discharge port on the other end side, a plurality of partition plates are erected at predetermined intervals on a bottom plate of a fluid chamber in the fluid chamber, and a plurality of partitions are provided. Chambers, and each partition plate is provided with openings of a predetermined width alternately between opposing side walls of the flow chamber to communicate the compartments with each other to form a zigzag-like powdery material flow path. A plurality of heat transfer tubes extending vertically and horizontally in each compartment so as to be positioned in the fluidized bed, and a spacer is provided between adjacent heat transfer tubes in the left and right direction. Are attached at intervals in the direction in which the heat transfer tubes extend. It was to the mounting configuration.

[0008]

The granular material supplied from the supply port to the fluidizing chamber is fluidized by vibrating the vibration chamber by the vibration generating device to form a fluidized bed, and the partition composed of a plurality of partition plates is formed. It flows toward the discharge port through a zigzag-shaped powdery material flow path that is communicated. During this time, the powder is heated by a plurality of heating tubes (heat transfer tubes) arranged vertically and horizontally in the fluidized bed and receives heat from a plurality of spacers attached between the left and right heat transfer tubes. Is heated.
The heat transfer area is increased by the heat transfer tubes and spacers in the layer, so that the granular material is efficiently heated. The spacers increase the heat transfer area and also act as heat transfer fins. Therefore, even when the temperature of the heating source cannot be increased due to the constraint conditions for maintaining the quality of the processed material, the heat transfer area is ensured to be sufficiently large, and the layer area, that is, the apparatus is reduced, and drying is efficiently performed.

In each compartment, the heat transfer tubes extend in the flow direction of the particles, so that the flow of the particles is smoothly flowed without being hindered by the heat transfer tubes. And since the flow path is a zigzag flow path, the flow path can be selected as a flow path having an optimum particle movement speed and length necessary for drying, and a short path of particles is prevented as much as possible and appropriate. By choosing an appropriate slenderness ratio, the layer area can be reduced and the device can be of an appropriate size.

On the other hand, spacers of a predetermined length are attached at predetermined intervals in the extending direction (axial direction) of the heat transfer tubes between the adjacent heat transfer tubes in the left-right direction, and each spacer is connected to the upper and lower heat transfer tubes. The mounting position is shifted by one pitch so that a fluidized bed is formed between the spacers in the vertical direction when the granular material moves in the flowing chamber,
Even if the processing amount is increased and the depth of the fluidized bed is increased as a whole, the fluidization can be favorably maintained as a shallow fluidized bed divided by spacers. Simultaneously, the fluidization is performed evenly over the entire bed because the particles of the granular material move so as to fall on adjacent spacers in steps in the axial direction of the heat transfer tube with the movement of the particles. In addition, when the apparatus is stopped, that is, when the fluidized bed is stopped, a space where no particles are present is formed at the lower portion of the lower surface of the spacer. Conversion is performed smoothly.

In the case where the spacers are tapered on the upper and lower surfaces in the direction of the flow of the granular material, a force is applied to move the particles moving in the vertical direction to the slope by vibration to move the particles forward. As a result, the particles can be reliably moved forward, and the short path of the particles can be more reliably prevented. In this case, the effect of preventing a short path of particles is further exhibited in combination with the predetermined feed speed secured by the zigzag flow path. By setting the slope of the lower surface of the spacer to be less than the angle of repose, a space can be more reliably formed below the lower surface of the spacer.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in the drawings. 1 is a schematic front sectional view showing one embodiment of a vibrating fluidized bed drying apparatus according to the present invention, FIG. 2 is a plan sectional view taken along line A-A of FIG. 1, and FIG. It is sectional drawing.

As shown in FIGS. 1 and 2, the drying apparatus main body 1 is formed in a box shape having a rectangular cross section, and the drying apparatus main body 1 has a bottom plate 1a supported by a foundation 20 via a support spring 15. I have. A supply port 2 for supplying a material to be dried (in this embodiment, gypsum containing crystallization water having an average particle diameter of 30 μm) is provided on the left side of one end of the drying apparatus main body 1. An outlet 3 from which dried gypsum is discharged is provided on the lower surface on the right side of the side. An exhaust port 12 is provided at the upper center of the main body 1. In addition, vibration generating devices such as vibrators (also referred to as vibrating devices) are provided at the central portions of the side walls 1a and 1b on both sides of the drying device main body 1, respectively.
In this embodiment, the vibration device 4 has a double amplitude of about 10 mm and a vibration frequency of about 10 Hz, whereby the drying apparatus main body 1 is vertically vibrated.

The upper portion of the bottom plate 1a inside the drying apparatus main body 1 is a fluid chamber 6, and the fluid chambers 6 are plural (four in this embodiment).
Partitioning plate 5 is vertically erected on the bottom plate 1a of the drying device main body 1 at substantially constant intervals in the direction from the supply port 2 to the discharge port 3 of the object to be dried, and is divided into a plurality (five in this embodiment). A chamber 7 is formed. Openings 6 having a predetermined width are alternately formed in the partition plates 5 between the opposed side walls 1b and 1c of the flow chamber 6, and the compartments 7 are communicated with each other to form a zigzag-shaped material to be dried. A (powder) channel is formed. As shown in FIGS. 1 and 3, the bottom plate 1 a is provided with an air distribution pipe 10 extending in the width direction of each compartment 7 and juxtaposed in the left-right direction.
As shown in FIG. 2, an air ejection hole 11 is formed in the air distribution pipe 10 so that air is ejected toward the bottom plate 1a.

In each of the compartments 7, a plurality of heating tubes 8 as heat transfer tubes extending in the width direction of the compartment 7, which is the flow direction of the granular material, are positioned in the fluidized bed F in the vertical and horizontal directions. It is arranged to be. In the present embodiment, the heating tubes 8 are arranged in eight stages, and the heating tubes 8 in each stage are formed by being folded back at both ends in the width direction of each compartment 7 as shown in FIG.
The heating tube 8 is also provided on the side wall (outer wall) of the drying device main body 1 and the partition plate 5. That is, the side wall (outer wall)
The partition plate 5 is configured by connecting a heating tube 8 with a flat plate. In this embodiment, the heating tubes 8 are arranged in a square array as shown in FIGS. As shown in FIG. 2, at the ends of upper and lower heating pipes 8 attached to the right end wall surface of the drying device main body 1, an inlet header 8a for a saturated steam as a heating source is provided, while it is attached to the left end wall surface. The heating tube 8 is provided with an outlet header 8b for saturated steam used for heat transfer.

As shown in detail in FIGS. 4 and 5, a spacer 9 having a predetermined length in the extending direction (axial direction) of the heating tube 8 is heated between the adjacent heating tubes 8 in the left-right direction. The tubes 8 are attached at predetermined intervals in the extending direction. And
The spacers 9 are attached to the upper and lower heating tubes 8 by shifting the attachment positions by one pitch. In this embodiment, the spacers 9 are also attached to the left and right heating tubes 8 at positions shifted by one pitch. Each of the spacers 9 is formed on the upper and lower surfaces so as to be inclined so as to be tapered toward the flow direction of the granular material.

As shown in FIGS. 6 and 7, the bottom plate 1a is provided with a saw-toothed surface in which a number of gradients 1ab descending in the flow direction of the particles to be dried are formed continuously. On the other hand, as shown in FIGS. 8 and 9, the bottom plate 1 a at the portion where the opening 6 of the partition plate 5 is located is turned smoothly without the particles being obstructed by the air dispersion pipe 10, and is turned into the adjacent compartment 7. As it flows in,
It is located on the upper surface of the air distribution pipe 10.

Next, the operation of the vibrating fluidized bed drying apparatus having such a configuration will be described. Gypsum with an average particle diameter of 30 μm containing crystallization water (internal water) is supplied from the supply port 2 of the drying device main body 1 and placed on the bottom plate 1 a of the leftmost compartment 7 in FIGS. Is operated to vertically vibrate the fluidized chamber 6, the particles of gypsum dihydrate are fluidized to form a fluidized bed F of a predetermined height, and the space between the compartments 7 formed by the partition plate 5 is shown in FIG. As shown in the figure, while flowing in a zigzag manner in the direction of arrow G, it heads toward the compartment 7 where the outlet 3 at the right end in the figure is located.
In addition, since the heating pipe 8 extends in the flow direction of the gypsum particles in each compartment 7, the particles flow smoothly along the heating pipe 8. The heating tubes 8 arranged in multiple stages (eight stages in this embodiment) are buried in a fluidized bed F formed by fluidization.

In the meantime, the gypsum dihydrate particles come into contact with the heating tube 8 and the spacer 9, and the heat from the heating tube 8 and the spacer 9 heated by the flow of the saturated steam as a heating source evaporates the water adhering to the surface to dry. Is done. In the drying of the dihydrate gypsum, the water of crystallization cannot be flown out and the saturated steam temperature as the heating source cannot be increased, but the heat transfer area is sufficiently large due to the in-layer heating pipe 8 and the spacer 9. When the particles are secured, the particles can be dried to a desired degree of drying by evaporating the moisture attached to the surface without increasing the layer area.

As shown in FIGS. 4 and 5, the spacers 9 are attached to the upper and lower heating tubes 8 at a position shifted by one pitch, so that the particles are separated from the compartment 7 of the flow chamber 6.
Is moved, the fluidized bed Fs is formed between the spacers 9 in the vertical direction, so that the fluidized bed Fs (height H) divided by the spacers 9 can maintain good fluidization and can be efficiently operated. Drying can be performed. FIG.
However, as can be seen, the particles are moved so as to fall on the adjacent spacer 9 at different levels in the axial direction (extending direction) of the heating tube 8 with the movement of the particles, so that uniform fluidization is performed. In this embodiment, since the spacers 9 are attached to the left and right heating tubes 8 at positions shifted by one pitch, the particles can be more uniformly filled as a whole, and a more uniform flow can be achieved. Has been implemented.

In the above evaporation and drying process, the drying flow path is formed as a zigzag passage between the compartments 7 defined by the partition plates 5, so that a desired residence for drying the gypsum dihydrate particles is obtained. As time is secured, mixing in the moving direction of the particles is prevented as much as possible, and the short path is prevented as much as possible. It is efficiently dried to the point. The drying apparatus main body 1 has an optimum slenderness ratio (ratio of vertical and horizontal lengths) due to the zigzag flow path.
Since the size is determined according to the above, the device does not become a slender device, and the installation area is set to an appropriate area.

In this embodiment, a certain amount of air is blown from the air ejection holes 11 of the air supply pipe 10 provided in the bottom plate 1a in order to lower the water vapor pressure of the exhaust gas and promote drying in the evaporation and drying processes. . The amount of air is smaller than the amount corresponding to the minimum fluidization speed, and the amount of particles jumping out is also small. Further, the surface of the bottom plate 1a has a saw-toothed surface provided with a large number of continuous gradients 1ab descending in the flow direction of the particles, so that the dihydrate gypsum particles can be reliably fed on the bottom plate 1a in the feeding direction (flow direction). ). In the vicinity of the opening 6 of the partition plate 5, the bottom plate 1a is
By being positioned as a plane on the surface of the zero, the air flows smoothly into the adjacent compartment 7 as shown by the arrow G in FIG.

On the other hand, in the present embodiment, as shown in FIG. 10, the upper surface 9a and the lower surface 9b of the spacer 9 are inclined so as to be tapered in the flow direction of the particles. The vibration force is applied to the particles by the spacers 9 so that the particles are moved obliquely upward and forward, and the particles moved upward by the spacers 9 located below hit the lower surface 9b and collide. It will rebound and move diagonally downward and forward. Therefore, the particles moving in the vertical direction due to the vibration are applied to the slopes of the upper surface 9a and the lower surface 9b to apply a force to move the particles forward, so that the particles can be surely moved forward, and the mixing of the particles before and after the movement direction is prevented. Thus, the short path of the particles can be more reliably prevented. In this case, the effect of preventing a short path of particles is further exhibited in combination with the predetermined feed speed secured by the zigzag flow path.

As shown in FIG. 11, when the drying apparatus main body 1 is stopped, that is, when the vibration action is stopped and the fluidized bed F is stopped, a space S free of particles is formed below the lower surface 9b of the spacer 9. By doing so, consolidation between the upper and lower spacers 9 can be avoided, and fluidization of particles can be smoothly performed at the time of restart. In this case, by setting the gradient of the lower surface 9b of the spacer 9 to be less than the angle of repose RA, the space S can be more reliably formed on the lower surface 9b of the spacer. If the slope of the lower surface 9b of the spacer 9 is a large inclined surface having a repose angle RA or more, no space is formed below the lower surface 9b because particles enter the lower surface 9b.

Next, a test example using the apparatus of this embodiment will be described. Heating tubes 8 of 1 inch are arranged in a square array (upper, lower, left and right, same pitch) at a pitch of 50.8 mm in each compartment 7 configured by providing four partition plates 5 in the flow chamber 6. Spacers 9 having a length of the heating tube 8 in the axial direction of 100 mm were attached between the heating tubes 8 at intervals of 100 mm in the axial direction of the heating tube 8.
The mounting pitches to the upper and lower heating tubes 8 were shifted by one pitch. The drying device main body 1 was set on four support springs 15.

Using the vibrating fluidized bed drying apparatus thus configured, dihydrate gypsum (CaSO ₄ .2H ₂ O) particles having an adhering water content of 10% and an average particle diameter of 30 μm are supplied from the supply port 2, With two vibration devices 4, both amplitudes are around 10 mm, frequency 10
By vibrating vertically at about Hz to form a vibrating fluidized bed F, saturated steam at 124 ° C. was supplied to the heating pipe 8 to heat it so that water of crystallization did not fly. In order to reduce the water vapor pressure of the exhaust gas and promote drying, the amount of particles that flow out from the air ejection holes 11 of the air dispersion pipe 10 provided in the bottom plate 1a is smaller than the amount corresponding to the minimum fluidization speed of the particles, and the amount of the particles jumping out is also small. A certain amount of air was blown. As a result, the surface adhered moisture was dried to 0.5% or less, and product particles having almost no drying unevenness were continuously obtained from the outlet 3.

In the above embodiment, the case where the vibrating fluidized bed apparatus is a drying apparatus has been described. However, the present invention can be suitably used as a thermal decomposition apparatus for thermally decomposing a substance to extract a gas having a specific component and composition. Can be. The heating medium of the heating tube 8 is not limited to steam, and a high-temperature molten salt or the like can be used.

[0028]

As is clear from the above description, according to the vibrating fluidized bed apparatus of the present invention, the function of mixing particles and preventing short paths inherent in the vibrating fluidized bed apparatus is further enhanced by the zigzag flow path. It can be assured. Further, the particles can efficiently absorb heat by coming into contact with a heat transfer tube such as a heating tube and a spacer in which a large heat transfer area is secured in the fluidized bed. Thereby, the layer area can be reduced. The fluidized bed is formed by combining predetermined shallow fluidized beds, so that the fluidized bed can be fluidized well and the bed area can be reduced. Furthermore, the device can be configured with an appropriate slenderness ratio in consideration of the moving speed or residence time of the particles, so that the layer area and the installation area can be made appropriate and the heat radiation amount can be reduced. it can.

When the apparatus of the present invention is applied as a fluidized bed drying apparatus, for example, even if the temperature of the heating source cannot be increased due to the restriction of the material to be dried, the bed area of the fluidized bed is reduced and the appropriate slenderness ratio is set. As a drying apparatus, uniform drying can be performed without causing mixing of undried particles or uneven drying, and drying can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a schematic front sectional view showing one embodiment of a vibrating fluidized bed drying apparatus according to the present invention.

FIG. 2 is a plan sectional view taken along line AA of FIG. 1;

FIG. 3 is a sectional side view taken along line B in FIG. 1;

FIG. 4 is a cross-sectional view taken along line C of FIG. 1 and is an enlarged partial side view of a heat transfer tube and a spacer.

FIG. 5 is a perspective view of a heat transfer tube to which a spacer is attached.

FIG. 6 is a cross-sectional view taken along line D in FIG. 1, showing a saw-toothed surface provided on a bottom plate.

FIG. 7 is a perspective view showing a bottom plate.

FIG. 8 is a sectional view taken along line EE of FIG. 2;

FIG. 9 is a cross-sectional view taken along line F of FIG. 8;

FIG. 10 is a diagram illustrating a forward movement effect of particles by a spacer.

FIG. 11 is a diagram showing a state of particles around a spacer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drying apparatus main body 1a Bottom plate 2 Dry material supply port 3 Dry material discharge port 4 Exciter (vibration generator) 5 Partition plate 5a Opening (partition plate) 6 Flow chamber 7 Separator 8 Heating pipe (heat transfer pipe) 9 Spacer 9a Spacer upper surface 9a Spacer lower surface 10 Air distribution pipe 12 Exhaust port 15 Support spring F Fluidized bed Fs Divided shallow fluidized bed S Spacer underside space

Claims (1)

(57) [Claims] An oscillating flow in which a fluid chamber is vibrated by a vibration generator to fluidize a granular material and flow the granular material from a supply port at one end of the fluid chamber to a discharge port at the other end. In the bed apparatus, a plurality of partition plates are erected at predetermined intervals on the bottom plate of the flow chamber in the flow chamber to form a plurality of compartments, and each partition plate is provided between the opposed side walls of the flow chamber. Openings having a predetermined width are alternately provided to connect the compartments to each other to form a zigzag-shaped powdery material flow path, and extend in each compartment in the flow direction of the powdery material so that the heat transfer tubes are vertically and horizontally. Multiple in the direction, arranged so as to be located in the fluidized bed, spacers are installed at intervals in the direction in which the heat transfer tubes extend between heat transfer tubes adjacent in the left-right direction,
A vibrating fluidized bed apparatus wherein the spacers are attached to the upper and lower heat transfer tubes by being shifted by one pitch.