JPS6158754B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a powder preheating device. More specifically, the present invention relates to a granular preheating device capable of preheating granular materials such as dolomite and quicklime, particularly granular materials such as sand and gravel, which are artificial lightweight aggregates used as aggregates for concrete.

A suspension type preheating device, which is attached to a cement firing kiln and is composed of a plurality of cyclone type heat exchangers, preheats the cement raw material while suspending the cement raw material using high-temperature exhaust gas discharged from the kiln. When using such a preheating device to preheat powder and granules, especially sand (powder with a diameter of 4 mm or less) or gravel (granules with a diameter of 4 to 15 mm) used as artificial lightweight aggregate, the sand is the same as a cement raw material. However, since gravel is relatively heavy, it is not possible to preheat it sufficiently using a suspension type preheating method, that is, a conventional cyclone type heat exchanger.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a preheating device for powder and granular materials, which can efficiently preheat both powders such as sand and granules such as gravel with the same equipment. , the gist of which includes at least one first cyclone and at least one second cyclone provided below the cyclone,
In the suspension type preheating device that preheats the powder while suspending the powder in the first cyclone with high-temperature gas discharged from the kiln, a cylinder with an open bottom is disposed in the first cyclone, and the high-temperature gas is placed in the cylinder. Provided with a heat exchanger heated by gas,
The granules supplied to the first cyclone pass through the heat exchanger, and the powder supplied to the first cyclone passes between a side wall of the first cyclone and an outer wall of the cylinder, and Two chutes and a chute switching means are provided at the bottom of both cyclones, one of the two chutes provided in the first cyclone is communicated with the second cyclone, and the other one is communicated with the inside of the kiln. ,
One of the two chute provided in the second cyclone is connected to the dust tank, and the other one is connected to the dust tank.
The book is communicated with the inside of the kiln, and the chute switching means connects the first cyclone and the kiln when preheating the powder, and also connects the second cyclone and the dust tank when preheating the powder. A granular material preheating device is characterized in that a cyclone and a second cyclone are connected, and the second cyclone and a kiln are connected so that both granular material and powder can be preheated.

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

FIG. 1 and FIG. 2 are conceptual diagrams showing the same powder preheating device according to the present invention, and FIG. 1 shows a case where gravel (granules with a diameter of 4 to 15 mm) is preheated.
Figure 2 shows the case of preheating sand (powder with a diameter of 4 mm or less).

1 and 2, 1 is a gravel supply feeder, 2 is an aerodynamic damper, 3 is a gravel hopper, and 4 is a first cyclone.
Inside the cyclone 4, an inner cylinder 5 with an open bottom is provided, and a packed bed type heat exchanger 6 is provided as a heat exchanger for granules in the inner cylinder 5. It is configured to pass through the heat exchanger 6. A chute branched into two is provided at the lower part of the first cyclone 4, and a seal damper 7 as a chute switching means is provided at the branch point,
One chute 8 is connected to the kiln 9 as a gravel chute, and a variable speed vibration feeder 10 for gravel is provided in the middle. The other chute 11
is connected to a second cyclone 18, which will be described below, as a sand chute. Further, 12 is a sand supply feeder, 13 is an aerodynamic damper, 14 is a sand hopper, 15 is a sand variable speed vibration feeder, 16 is a sand chute, and 17 is a high-temperature gas duct. The sand chute 16 is connected to the first cyclone 4 and the second cyclone 18, and the sand chute 16 is connected therebetween, and a dispersion plate 19 is provided at the communicating point. The second cyclone 18
A chute branched into two is provided at the bottom of the chute, and a chute switching seal damper 20 is provided at the branching point, one chute 21 is connected to the inside of the kiln 9 as a sand chute, and the other chute 22 is used as a dust chute. Connect to the dust tank,
Moreover, a rotary feeder 23 is provided in the middle. 24 is a kiln bottom housing, 25 is a high-temperature gas duct communicating with the housing 24 and the second cyclone 18, and a sand chute 11 branched from the first cyclone in the middle of the duct 25.
are communicated with each other, and a dispersion plate 26 is provided at the communicating point. Reference numeral 27 denotes a high-temperature gas discharge duct that communicates with the packed bed heat exchanger 6 in the first cyclone.

First, the case of preheating gravel will be explained according to FIG. In this case, sand supply feeder 1
2. The variable speed vibration feeder 15 is stopped, the air damper 13 is closed, the damper 7 of the first cyclone is switched to the gravel chute 8, and the damper 20 of the second cyclone is switched to the dust chute 22. Gravel is supplied from the supply feeder 1 to the hopper 3 through the aerodynamic damper 2, and then
It is discharged into the kiln 9 through a packed bed heat exchanger 6, a chute 8, and a vibration feeder 10 in the cyclone. In this case, the variable speed vibrating feeder 1 is used so that the gravel forms a packed bed in the packed bed heat exchanger 6.
Adjust to 0. On the other hand, high-temperature gas discharged from the kiln 9 flows from the kiln bottom housing 24 to the duct 2.
5, enters the second cyclone 18, becomes a swirling flow within the cyclone 18, is separated from the dust in the gas, passes through the duct 17, and enters the first cyclone 4.
to go into. The separated dust is discharged into a dust tank through a chute 22 at the bottom of the cyclone and a 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 gravel forms 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, thereby efficiently preheating the gravel raw material.

Next, the case of preheating sand will be explained according to FIG. In this case, it is exactly the same as when preheating cement raw materials, and the gravel supply feeder 1,
The variable speed vibration feeder 10 is stopped, the air damper 2 is closed, and the dampers 7 and 20 of the first and second cyclones are both switched to the sand chute 11 and 21. The sand is fed from the supply feeder 12 through the aerodynamic damper 13 to the hopper 14, fed into the chute 16 by the variable speed vibrating feeder 15, dispersed by the distribution plate 19, and together with the hot gases in the duct 17 described below. Entering the first cyclone 4. In the cyclone 4, sand suspended by high-temperature gas is preheated while swirling between the cyclone side wall 4a and the inner cylinder 5, falls below the cyclone, and is sent to the chute 11 through the damper 7. The sand raw material 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 sand raw material suspended by the high temperature gas is 2nd cyclone 18
The heat is further preheated, falls to the lower part of the cyclone, and is discharged into the kiln 9 through the damper 20 and the chute 21. 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 sand that has flowed in from the chute 11, enters the second cyclone 18, swirls within the cyclone 18, and preheats the sand. Rear duct 17
The sand flowing in from the chute 16 is suspended again and enters the first cyclone 4.
After preheating the sand raw material while rotating as described above, the packed bed heat exchanger 6 and the discharge duct 2
It is discharged through 7.

As described above, the powder preheating device according to the present invention includes:
Suspension type preheating comprising at least one first cyclone and at least one second cyclone provided at the lower stage of the cyclone, and preheating the powder while suspending it with high temperature gas discharged from the kiln in the first cyclone. In the apparatus, a cylinder with an open bottom surface is disposed in the first cyclone, a heat exchanger heated by the high temperature gas is provided in the cylinder, and the granules supplied to the first cyclone are heated by the heat exchanger. The powder supplied to the first cyclone is configured to pass between the side wall of the first cyclone and the outer wall of the cylinder while passing through the inside of the vessel, and furthermore, two shoots and a shoot switch are provided at the bottom of both the cyclones. means for communicating one of the two chutes provided in the first cyclone with the second cyclone and communicating the other one with the inside of the kiln; One of them is connected to the dust tank and the other one is connected to the inside of the kiln, and the chute switching means connects the first cyclone and the kiln when preheating the granules, and also connects the second cyclone and the dust tank. At the same time, the first cyclone and the second cyclone were connected, and the second cyclone and the kiln were connected when preheating the powder, so that it is the same whether it is a light powder such as sand or a heavy granule such as gravel. By simply switching the dampers using the preheating device, it is possible to preheat both efficiently. Therefore,
Many economic benefits can be obtained, including fuel costs, equipment costs, work efficiency, and more.

In short, the preheating device according to the present invention is a suspension type preheating device comprising a plurality of cyclones, in which at least one cyclone is configured as a granule heat exchanger and a suspension type powder heat exchanger. It is not limited to the embodiments shown in FIGS. 1 and 2, and may be configured as shown in FIGS. 3 and 4, for example, as long as it does not exceed the gist of the present invention. Furthermore, the fifth example is a cyclone configured as a dual-purpose heat exchanger.
In addition to those shown in FIGS. 6 and 6, various other devices that meet the purpose of the present invention can be used.

The embodiments shown in FIGS. 3 and 4 are both shown in FIG.
The embodiment shown in FIG. 2 is connected in two stages, and FIG. 3 shows the case where the gravel raw material is preheated, and FIG. 4 shows the case where the sand raw material is preheated. In both figures, the parts related to the first and second cyclones in the upper row are numbered in the same way as in FIGS. It is written as follows. The preheating process of the equipment shown in both figures is similar to the preheating process of the equipment shown in Figures 1 and 2.
It is repeated several times. In addition, FIGS. 5 and 6 are cross-sectional conceptual diagrams showing an example of a cyclone constructed as a suspension-type heat exchanger for powder, and FIG. However, FIG. 6 is an enlarged view of another embodiment. In the device shown in FIG. 5, a plurality of outer conical rings 28 whose diameters increase upward are disposed coaxially at predetermined intervals in the inner cylinder 5, and outer conical rings 28 whose diameters increase upward are disposed coaxially within the inner cylinder 5. Inner conical ring 2 with increased diameter
9 are coaxially arranged at predetermined intervals, and the outer conical ring 28
and the inner conical ring 29 is the hopper 3
This becomes a passage for gravel to pass through as shown by arrow A, and high-temperature gas flows inside the inner conical ring 29 as shown by arrow B.
It becomes a passageway that flows out to the discharge duct 27 as shown in FIG. Note that hangers that support each ring are not shown. In the one shown in FIG. 6, a cylindrical outer net 28' is provided in the inner tube 5, and a cylindrical inner net 2 is also provided in the outer net 28'.
9' are provided coaxially, and the space between the outer net 28' and the inner net 29' and within the inner net 29' serves as a passage for gravel and high-temperature gas as described above.

[Brief explanation of the drawing]

FIGS. 1 and 2 are conceptual diagrams showing one embodiment of the apparatus according to the present invention, FIGS. 3 and 4 are conceptual diagrams showing other embodiments, and FIGS. 5 and 6 are respectively FIG. 2 is a cross-sectional conceptual diagram showing an embodiment of a cyclone configured as a dual-use suspension type powder heat exchanger. 4... First cyclone configured as a suspension-type powder heat exchanger for granules, 6... Heat exchanger for granules, 7... Shute switching means, 8, 11
...Chute provided in the first cyclone, 9...Kiln, 18...Second cyclone, 21, 22...
Two chutes installed in the second cyclone, 20...
...Shute switching means.

Claims (1)

[Claims] 1 A suspension type comprising at least one first cyclone and at least one second cyclone provided at the lower stage of the cyclone, and preheating the powder while suspending it with high temperature gas discharged from the kiln in the first cyclone. In the preheating device,
A cylinder with an open bottom is disposed inside the first cyclone, and a heat exchanger heated by the high-temperature gas is installed inside the cylinder, so that the granules supplied to the first cyclone pass through the heat exchanger. The powder supplied to the first cyclone is configured to pass between the side wall of the first cyclone and the outer wall of the cylinder, and further provided with two shoots and a shoot switching means at the bottom of both the cyclones. , one of the two chute provided in the first cyclone communicates with the second cyclone and the other one communicates with the inside of the kiln, and the two chute provided in the second cyclone
One of the chute is connected to the dust tank and the other is connected to the inside of the kiln, and the chute switching means connects the first cyclone and the kiln when preheating the granules, and connects the first cyclone and the kiln to the second cyclone. A cyclone and a dust tank are connected, and when preheating the powder, the first cyclone and the second cyclone are connected, and the second cyclone and the kiln are connected so that both the granules and the powder can be preheated. A powder and granular material preheating device characterized by: