JPS6145156B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a preheating device for powder and granular materials.

A suspension type preheating device, which is equipped with one or more cyclone type heat exchangers attached to a conventional material-calcining kiln, preheats the material to be preheated while floating and swirling it within the cyclone using high-temperature exhaust gas discharged from the kiln. If the material to be preheated is a relatively light powder, it can be sufficiently suspended and swirled to preheat it, but if it is a relatively heavy granule, it cannot be sufficiently preheated because it does not float and swirl.
Therefore, for example, when preheating sand (powder with a diameter of 4 mm or less) or gravel (granular material with a diameter of 4 to 15 mm) to be used as artificial lightweight aggregate for concrete, it is necessary to A separate preheating device (for body use) is required.

In view of the above circumstances, Hondekajin has previously applied for a powder preheating device that can efficiently preheat both relatively light and heavy powders using the same device. did. Such an apparatus is shown in FIGS. 1 and 2. The apparatus shown in the figure is a powder granule in which at least one cyclone of a suspension type preheating device is configured as a dual-purpose cyclone type heat exchanger to function as a granule heat exchanger and a suspension type powder heat exchanger. FIG. 1 shows the case of preheating granules, and FIG. 2 shows the case of preheating powder.

In the figure, 1 is a feeder for granules, 2 is an aerodynamic damper, 3 is a hopper for granules, and 4 is a first cyclone configured as a dual-purpose cyclone type heat exchanger. An open inner cylinder 5 is provided, and a packed bed heat exchanger 6 is provided in the inner cylinder 5 as a heat exchanger for granules, and the granules supplied to the hopper 3 are transferred to the packed bed heat exchanger 6.
It is designed so that it passes through the inside. A chute branched into two is provided at the lower part of the first cyclone 4, and a first seal damper 7 as a chute switching means is provided at the branch point, and one of the granule chute 8 is communicated with the inside of the kiln 9. A variable speed vibrating feeder 10 for granules is provided in the middle. The other chute 11 for grain powder is connected to the second cyclone 1 described below.
It is connected to 8. Further, 12 is a supply feeder for powder, 13 is an air damper, 14 is a hopper for powder, 15 is a variable speed vibration feeder for powder, 16 is a chute for powder, and 17 is a duct for high temperature gas. The duct 17 communicates with the first cyclone 4 and the second cyclone 18, and communicates with the powder chute 16 in the middle thereof, and a dispersion plate 19 is provided at the communicating point. A chute branched into two is provided at the lower part of the second cyclone 18, and a second shield damper 20 for switching the chute is provided at the branching point.One powder chute 21 communicates with the inside of the kiln 9, and the other dust chute 22
is communicated with the dust tank, and a rotary leaf feeder 23 is provided in the middle. 24 is a kiln bottom housing; 25 is a high-temperature gas duct that communicates with the housing 24 and the second cyclone 18;
The powder chute 11 is communicated in the middle of the duct 25, and a dispersion plate 26 is provided at the communicating point. 27 is a high-temperature gas discharge duct that communicates with the packed bed heat exchanger 6 in the first cyclone.

First, the case of preheating the granules will be explained according to FIG. In this case, the powder supply feeder 12 and the variable speed vibration feeder 15 are stopped, the aerodynamic damper 13 is closed, the first seal damper 7 is sent to the granule chute 8, and the second seal damper 2 is
0 is switched to the dust chute 8, and the second seal damper 20 is switched to the dust chute 22.
The granules are fed from a feeder 1 through an air damper 2 to a hopper 3, and are discharged into a kiln 9 through a packed bed heat exchanger 6 in a first cyclone, a chute 8, and a vibratory feeder 10.
In this case, the variable speed vibrating feeder 10 is adjusted so that the granules form a packed bed in the packed bed heat exchanger 6. On the other hand, high temperature gas discharged from the kiln 9 enters the second cyclone 18 from the kiln bottom housing 24 through the duct 25, and enters the second cyclone 18.
It becomes a swirling flow inside and is separated from the dust in the gas.
It enters the first cyclone 4 through the duct 17. The separated dust is sent to the chute 22 at the bottom of the cyclone.
The dust is then discharged to the dust tank through the rotary leaf feeder 23. The high temperature gas that has entered the first cyclone 4 flows to the lower part of the cyclone while swirling between the outer wall 4a and the inner cylinder 5 of the cyclone 4, passes through the packed bed heat exchanger 6, and is discharged from the duct 27. . In this case, the granules form a packed bed in the packed bed heat exchanger 6, and the high temperature gas passes through the packed bed in a direction perpendicular to the packed bed to efficiently preheat the granules.

Next, the case of preheating the powder will be explained according to FIG. In this case, it is sufficient to function as a normal suspension type preheating device, and the granule supply feeder 1 and the variable speed vibration feeder 10 are stopped.
The airlock damper 2 is closed, and the first and second seal dampers 7 and 20 are both closed and the powder sheets 11 and 2 are closed.
Switch to 1. Powder is supplied to feeder 12
From there, through the aerodynamic damper 13 to the hopper 1
4, is fed into a chute 16 by a variable speed vibratory feeder 15, is dispersed by a distribution plate 19, and enters the first cyclone 4 together with hot gas in a duct 17, which will be described below. The cyclone 4
Inside, the powder suspended by the high-temperature gas is preheated while swirling between the cyclone outer wall 4a and the inner cylinder 5, falls below the cyclone, and is sent to the chute 11 through the damper 7. The powder sent to the chute 11 is dispersed by the dispersion plate 26 and sent to the second cyclone 18 together with the high temperature gas in the duct 25 described below, and the powder suspended by the high temperature gas is mixed with the high temperature gas. 2nd cyclone 1
8, further falls to the lower part of the preheated cyclone, passes through the damper 20 and the chute 21, and is discharged into the kiln 9. On the other hand, high-temperature gas discharged from the kiln 9 passes through the duct 25 from the kiln bottom housing 24, suspends the powder that has flowed in from the chute 11, enters the second cyclone 18, swirls within the cyclone 18, and collects the powder. After preheating, the powder passes through the duct 17, suspends the powder that has flown in from the chute 16 again, and enters the first cyclone 4. In the cyclone 4, the powder is also preheated while swirling as described above, and then transferred to the packed bed. It is discharged through a type heat exchanger 6 and a discharge duct 17.

As mentioned above, the powder preheating device filed earlier is
At least one cyclone heat exchanger of the suspension type preheating device is configured as a dual-purpose cyclone type heat exchanger to act as a granule heat exchanger and a suspension type powder heat exchanger. In the case of heavy granules, the function of the cyclone as a suspension-type powder heat exchanger is used, and in the case of heavy granules, the function as a granule heat exchanger is used.
In this way, both light and heavy powders can be preheated efficiently using the same preheating device and simply by switching dampers, resulting in savings in fuel costs, equipment costs, work efficiency, and many other economics. effect can be obtained.

However, in the powder/granular material preheating device configured as described above, whether or not it is possible to efficiently preheat the powder or granules depends on how the dual-purpose cyclone heat exchanger is configured. . In the dual-purpose cyclone heat exchanger shown in Figures 1 and 2, the high-temperature gas comes into contact (heat exchange) with the particles only once, but it has been improved so that this contact occurs multiple times. If so, the granules can be preheated more efficiently.

In view of the above circumstances, the present invention provides a powder/granular material preheating device as described above, in which a dual-purpose cyclone type heat exchanger is configured such that the granular material and high-temperature gas come into contact with each other multiple times within the heat exchanger. The object of the present invention is to provide a preheating device for powder and granular materials that can efficiently preheat granular materials. In a powder preheating device configured as a cyclone-type heat exchanger for powder and granular materials to function as a heat exchanger for powder and a suspension-type heat exchanger for powder, the cyclone-type heat exchanger An inner cylinder with an open bottom surface is provided within the outer cylinder, a cylindrical outer net is provided within the inner cylinder, and a similarly cylindrical inner net is provided coaxially within the outer net, and the inner cylinder and outer net are connected coaxially to each other. The apparatus for preheating powder or granular material is characterized in that it is a heat exchanger in which partition walls provided between the two and partition walls provided within the inner net are arranged alternately in the vertical direction.

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the drawings.

FIG. 3 is a conceptual diagram showing an embodiment of the dual-purpose cyclone type heat exchanger of the powder/granular material preheating device according to the present invention, and this heat exchanger is connected to the first cyclone 4 shown in FIGS. 1 and 2. It is used instead. The dual-purpose cyclone heat exchanger 4 shown in the figure has an inner cylinder 5 with an open bottom surface inside the cyclone outer cylinder 4a, and a cylindrical outernet 28 inside the inner cylinder 5.
A cylindrical inner net 29 is provided coaxially within the outer net 28, and one or more partition walls 30 (one in this embodiment) are provided between the inner cylinder 5 and the outer net 28, and the inner There is also one or more sheets (in this example, one sheet) in the net 29.
2) partition walls 31 are provided, and both partition walls 30 and 31 are arranged alternately with each other at a predetermined interval in the vertical direction. Therefore, the high temperature gas entering the cyclone type heat exchanger 4 from the duct 17 is transferred to the outer net 28 and the inner net 2 as shown by the arrows in the figure.
The granules are brought into contact with the granules filled between the granules 9 and 9 for a total of three times, and after the granules are sufficiently preheated, they are discharged through the discharge duct 27. The number of times of contact can be arbitrarily changed by increasing or decreasing the number of partition walls 30, 31.

FIG. 4a is a cross-sectional conceptual diagram showing another embodiment of the main-purpose cyclone type heat exchanger, FIG. 4b is a conceptual cross-sectional diagram along the line BB of FIG. 4a, and FIG. FIG. 4 is a conceptual perspective view showing a main part of the heat exchanger shown in FIG. 4a in a broken state; The basic structure of the heat exchanger 4 according to this embodiment is the same as that shown in FIG. Discharge pipes 32 and 33 are provided for discharged fine particles).
That is, the partition wall 31 in the inner net has a conical shape whose diameter increases upwardly, and a discharge pipe 32 is communicated with the lower apex of the partition wall 31. The partition wall 30 provided between the inner cylinder 5 and the outer net 28 has a conical ring shape whose diameter increases downwardly, and a cylindrical partition wall extension member 30a extends from the lower end of the outer periphery of the partition wall 30. 5 and the cylindrical partition wall extension member 30a, an annular spill passage 33a is formed between the passage 33a and the cylindrical partition wall extension member 30a.
A zigzag-shaped guide plate 33b is provided inside the passage 33, and four triangular hopper parts 33c are connected in the circumferential direction within the passage 33, and a discharge pipe 33 is connected to the lower apex of each hopper part 3c. I've let it happen. In addition, in FIG. 4a, the hatched portion is the pipe 33. That is, the lower end position of the inner cylinder 5 coincides with the lower end position of the partition wall extension member 30a, and the pipe 33 is below both lower ends.

According to the dual-purpose cyclone heat exchanger shown in this embodiment, the high temperature gas entering from the duct 17 descends while swirling between the outer cylinder 4a and the inner cylinder 5, as shown by the arrow in the figure. 5, passes through the granule packed bed, enters the inner net 29, and then 2
The granules pass through the packed bed and are discharged from the discharge duct 27. Spills generated when the high temperature gas passes through the granular packed bed are discharged from both partition walls 30 and 31 through discharge pipes 32 and 33. That is, the spill that has fallen onto the partition wall 31 flows down along the slope of the partition wall 31 and enters the pipe 32. The spill that has fallen onto the partition wall 30 similarly flows down along the slope of the partition wall 30, enters the annular spill passage 33a, and enters the four pipes 33 from the four hopper portions 33c.

FIG. 5 is a conceptual longitudinal cross-sectional view showing still another embodiment of the dual-purpose cyclone type heat exchanger according to the present invention. The heat exchanger shown in the figure is constructed based on the same concept as the heat exchanger shown in FIG. The number of times the packed bed is contacted is 4 times. That is, the inner cylinder 5 and the outer net 2
Two partition walls 30 are provided between the upper partition wall 3 and the upper partition wall 3.
0, the partition wall extension member 30a, the spill passage 33a, the zigzag-shaped guide member 33b, the pipe 33, etc. are the fourth
The structure is similar to that shown in the figure, and the lower partition wall 30', partition wall extension member 30'a, spill passage 33'a, zigzag-shaped guide plate 33'b, and pipe 33'b are also structured in the same manner. However, the spill passage 3'a communicating with the lower partition wall 30' is connected to the upper partition wall extension member 30a.
and a lower partition wall extension member 30'a. The partition wall 31 and pipe 32 in the innernet 29 are also similar to those shown in FIG. In this embodiment, the number of times of contact is increased by 4, so the inner cylinder 5, outer net 28, inner net 29, etc. are extended above the cyclone outer cylinder 4a, and the inside of the discharge duct 27 is extended. is communicated with the inner cylinder 5.

FIG. 6 is also a longitudinal cross-sectional conceptual diagram showing an embodiment of the dual-purpose cyclone type heat exchanger according to the present invention, and the embodiment shown in this figure has almost the same structure as the embodiment shown in FIG. Furthermore, only the lower partition wall 30' provided between the inner cylinder 5 and the outer net 28 has been changed. That is, a guide ring 24 having a dogleg-shaped cross section is provided on the partition wall 30' so that its apex is located inside, and the lower ring piece 34b of the ring 34 and the partition wall 30' form a spill passage 33'a. The upper ring piece 34a is configured to guide the spill to the passage 33'a. Of course, a zigzag-shaped guide plate 33'b is provided in the spill passage 33'a to form a hopper section, and a pipe 33' is provided at the bottom of the hopper section.
are communicated.

The number of hopper portions 33c (four in the embodiment shown in FIG. 4) in the spill passages 33a, 33'a shown in FIGS. By selecting the shape of 'b, it may be changed arbitrarily.

Since the powder preheating device according to the present invention is equipped with the dual-purpose cyclone heat exchanger configured as described above, when preheating the granules, high-temperature gas passes through the packed bed of the granules multiple times. . Therefore, an extremely high heat exchange rate can be obtained and the granules can be sufficiently preheated. In addition, in order to increase the number of times that the high temperature gas comes into contact with the particles, it is sufficient to increase the number of partition walls, and if a large amount of spill occurs, a hopper is installed at each partition wall as shown in Figures 4 to 6. It is sufficient to provide a spill discharge means constituted by a discharge pipe or the like.

Note that this device can also be used as a device for preheating granules such as dolomite and quicklime. Further, as the net, in addition to a normal net, a perforated plate or the like which has the same effect as a net may be used.

[Brief explanation of the drawing]

1 and 2 are conceptual diagrams showing an example of a powder/granular material preheating device equipped with a dual-purpose cyclone type heat exchanger, and FIGS. 3 to 6 are respectively diagrams showing the dual-purpose cyclone type heat exchanger according to the present invention. It is a figure showing an example,
Fig. 3, Fig. 4a, Fig. 5, and Fig. 6 are longitudinal cross-sectional conceptual diagrams, Fig. 4b is a sectional view taken along line B-B of Fig. 4a, Fig. 4
Figure c is a partially cutaway perspective view showing the main parts of the heat exchanger shown in Figure 4a. 4... Dual-purpose cyclone heat exchanger, 4a... Cyclone outer cylinder, 5... Inner cylinder, 28... Outernet, 29... Inner net, 30, 31...
bulkhead.

Claims (1)

[Claims] 1. At least one cyclone heat exchanger of a suspension type preheating device is a cyclone type heat exchanger for both powder and granular materials so that it can function as a granule heat exchanger and a suspension type granule heat exchanger. In the powder and granular material preheating device configured as an exchanger, the dual-purpose cyclone type heat exchanger has an inner cylinder with an open bottom inside the cyclone outer cylinder, a cylindrical outernet inside the inner cylinder, and a cylindrical outer cylinder. A similarly cylindrical inner net is provided coaxially within the outer net, and partition walls provided between the inner cylinder and the outer net and partition walls provided within the inner net are arranged alternately in the vertical direction. A powder preheating device characterized by being a heat exchanger. 2. The powder preheating device as set forth in claim 1, wherein each of the partition walls is provided with means for discharging spills that have fallen onto the partition walls.