JPH0424394Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a sintering device for powder raw materials such as cement, alumina, lime, etc., and more specifically relates to an expansion joint in this device.

(Prior Art) Conventionally, there is an apparatus for firing powder raw materials for cement, as shown in, for example, Japanese Utility Model Publication No. 59-24352.
In this configuration, a rotary kiln-type firing furnace for firing powder raw materials to obtain clinker, and a cooler for cooling the clinker discharged from this firing furnace with an air flow are provided. A calcining furnace is provided upstream of the furnace. In addition, the air outlet of the cooler is connected to the calciner through an air duct, and the exhaust air from the cooler burns fuel in the calciner, resulting in hot gas and exhaust gas from the calciner. Due to this, powder raw materials are now calcined in a calcining furnace.

By the way, the exhaust air from the cooler that cools the clinker is usually at a high temperature of about 700°C, so when this high temperature exhaust air flows through the air duct, the air duct is heated by the heat of the exhaust air. trying to expand. Therefore, in order to allow the air duct to expand, there are conventional air ducts in which a plurality of bellows-type expansion joints are provided in the middle of the air duct.

The above expansion joint will be explained with reference to FIG.

In the figure, 41 is an air duct, and this air duct 41 has a plurality of duct pipes 42 arranged in parallel in the axial direction.
Expansion joints 43 are interposed between 2 and 42, respectively. The inner peripheral surface of the duct pipe 42 is lined with a refractory material 45, and between the refractories 45, 45 of the adjacent duct pipes 42, 42, the duct pipes 42, 42 are allowed to extend in the axial direction. Therefore, a gap is formed.

The expansion joint 43 has a bellows 4 having a U-shaped cross section.
6, and each end of the bellows 46 is fixed to the opposite ends of the adjacent duct pipes 42, 42, respectively. Further, in order to suppress clinker dust from accumulating in the bellows 46, a heat-resistant bulk 48 made of asbestos is inserted into the bellows 46, and is guided so as to cover the gap between the refractories 45, 45. A plate 49 is provided.
This guide plate 49 is for guiding the exhaust air flowing in the direction shown by arrow G in the figure so that it does not enter the above-mentioned gap. 50 is a duct support, and this duct support 50 supports the duct pipes 42, 42 so that the expansion joint 43 is sandwiched therebetween.

When high-temperature exhaust air flows through the air duct 41, the duct pipe 42 expands due to the heat of the exhaust air and extends in the axial direction.
6 is allowed by shrinking in the axial direction. Also,
When the air duct 41 cools due to a decrease in the temperature of the discharged air, the duct pipe 42 contracts in the axial direction, and the contraction of the duct pipe 42 at this time is allowed by the bellows 46 extending in the axial direction.

(Problems to be solved by the invention) By the way, in the above-mentioned firing apparatus, since the air duct 41 connects the calcining furnace on the powder raw material inlet side of the firing furnace and the cooler on the clinker discharge side, there are problems due to its configuration. This air duct 41 has a long dimension, and the amount of expansion and contraction of this air duct 41 is also large.

On the other hand, the bellows type expansion joint 43 was originally
Since it is not structurally possible to accommodate a large amount of expansion and contraction, a large number of the expansion joints 43 are required to accommodate a large amount of expansion and contraction of the air duct 41. Further, duct supports 5 that support the air duct 41 at positions sandwiching each expansion joint 43 are also provided.
0 is required, and the structure of the firing apparatus as a whole is complicated.

In addition, in the expansion joint 43, when the bellows 46 contracts, the bulk 48 inside the bellows 46 is compressively deformed, but when the bellows 46 is expanded, the bulk 48 has no restorability. The bulk 48 will not follow and a gap will be created between the bellows 46 and the bulk 48. Therefore, clinker dust contained in the discharged air enters the gap between the refractory material 45 and the guide plate 49 through the gap between the adjacent refractory materials 45, 45, and accumulates therein. In this case, the function of the expansion joint 43 is impaired and the air duct 41 and the duct support 5 supporting the air duct 41 are damaged.
As a result, the air duct 41 and the duct support 50 may be damaged.

(Purpose of the invention) This invention was made with attention to the above-mentioned circumstances, and it is possible to simplify the overall configuration of the powder raw material firing apparatus by making the expansion joint compatible with the large amount of expansion and contraction of the air duct. Moreover, it is an object of the present invention to prevent dust contained in air discharged from a cooler from accumulating on an expansion joint and impairing the function of the expansion joint.

(Structure of the device) The feature of this device for achieving the above object is that the air duct that connects the air outlet of the cooling machine and the calciner is cut off in the middle, and this air duct is connected to at least the third section. The divided end of the second duct is fitted into the divided end of the first duct so as to be relatively movable in the axial and radial directions. The point is that a sealing material is interposed between the ducts.

(Example) Hereinafter, an example of this invention will be described with reference to FIGS. 1 to 5.

1 to 3 show a first embodiment.

In FIG. 2, reference numeral 1 denotes a rotary kiln-type firing furnace for producing clinker by firing cement powder raw materials, and 2 a clinker cooler that cools the clinker discharged from the firing furnace 1 with an air flow. On the upstream side of the firing furnace when viewed in the flow direction of the powder raw material, there is a preheating device 3 for preheating the powder raw material;
A calcining furnace 4 for calcining the powdered raw material is provided. Further, a raw material feeder 5 for supplying powder raw materials to the preheating device 3 is provided.

At the connection between the clinker outlet side of the kiln 1 and the cooler 2, a fuel combustion means 6a is provided which burns fuel using high-temperature air from the cooler 2. On the other hand, the cooler 2 is connected with a blower 7 that supplies air for clinker cooling to the cooler 2, and an exhaust fan 8 that discharges a portion of high-temperature air from the cooler 2.

The preheating devices 3 are stacked vertically, and
It has four stages of cyclones C ₁ to _{C 4} that are connected to each other. That is, the cyclone C ₁ located above
Connect the gas inlets of ~ _C3 and the gas exhaust ports of cyclones _C2 ~ _C4 located below to gas duct 1.
They are connected by 0a to 10c. Further, the gas outlet of the calciner 4 and the gas inlet of the lowermost cyclone _C4 are connected by a gas duct 10d. Furthermore, the gas outlet of the uppermost cyclone C ₁ is connected to an exhaust fan 11 by a gas duct 12 .

On the other hand, the powder discharge ports of the cyclones C ₁ and C ₂ located above are the same as those of the cyclones C ₂ and C ₃ located below.
The gas inlet side gas ducts 10b and 10c are connected to the middle portions thereof by raw material chute 13a and 13b, respectively. Also, the top cyclone above
A raw material input chute 14 into which powdered raw material is inputted from the raw material feeder 5 is connected to a midway portion of the gas duct 10a on the gas inlet side of _C1 . Furthermore, the powder discharge port of the lowest stage cyclone C ₄ is connected to the inlet end cover 1 a of the firing furnace 1 through a raw material chute 15 .

A fuel combustion means 6b is provided in the middle of the calciner 4 in the vertical direction. Further, the lower end of the calcining furnace 4 is connected to the upper end of the inlet end cover 1a of the firing furnace 1. Furthermore, in order to supply air for fuel combustion in the fuel combustion means 6b, the air outlet of the cooler 2 is connected to the calciner 4 by an air duct 17 below the fuel combustion means 6b.

A dust settling chamber 18 is interposed in the middle of the air duct 17 in order to collect clinker dust contained in the exhaust air discharged from the cooler 2. A dust outlet of the dust settling chamber 18 is connected to the cooler 2 through a dust chute 19, so that the clinker dust is collected into the cooler 2.

On the other hand, the third stage cyclone of the preheating device 3
The powder outlet of C ₃ is connected to the raw material chute 1 in the calcining furnace 4.
3c.

The high-temperature airflow that cooled the clinker with the cooler 2 is used as combustion air in the calcining furnace 1 and the calcining furnace 4, respectively, and becomes hot gas, and this hot gas is sucked by the exhaust fan 11 and finally The hot gas flows from the lower cyclone C ₄ to the uppermost cyclone C ₁ through gas ducts 10 a to 10 c (the flow of hot gas is indicated by solid arrows in the figure).

On the other hand, the powder raw material input from the raw material input chute 14 is heated sequentially by the hot gas rising in each gas duct 10a to 10c, and flows from the uppermost cyclone _C1 to the third cyclone _C3 , where it is preheated. . This preheated powder raw material flows from the third stage cyclone _C3 to the calciner 4, where it is combined with the heat from the fuel combustion of the fuel combustion means 6b and the heat of the exhaust gas from the calciner 1. Calcined.
Then, this calcined powder raw material flows from the calciner 4 to the calciner 1 through the lowermost cyclone _C4 ,
It is fired in the firing furnace 1 to become clinker, cooled in the cooler 2, and transferred to the next process as a finished clinker (the flow of the powdered raw material is indicated by broken line arrows in the figure).

Here, the air duct 17 will be explained with reference to FIG.

The air duct 17 is divided in the middle,
The first duct 2 connected to the air outlet of the cooler 2
0, and a second duct 21 connected to the air inlet of the calcining furnace 4. In this case, the air duct 17 may be composed of the first and second ducts 20, 21 and other ducts. The dust settling chamber 18 is formed near the divided end of the first duct 20. An expansion joint 23 is interposed between the divided ends of the first duct 20 and the second duct 21. When it expands and contracts, it allows this expansion and contraction.

Duct supports 24a and 24b are provided to support the second duct 21. The second duct 21 of these duct supports 24a and 24b
Duct support 24a located at the side end of the calcining furnace 4
is fixed on the pedestal 25a, and the other duct support 24b is slidable on the pedestal 25b.
Therefore, when the second duct 21 expands and contracts, the duct support 24b slides on the pedestal 25b. In this case, the calcining furnace 4 of the second duct 21
Instead of the duct support 24a located at the side end,
Any desired one of the other duct supports 24b may be fixed, and the others may be slidable.

Here, the expansion joint 23 will be explained with reference to FIG.

The first duct 20 has a dust settling chamber 1 at its divided end.
It has a cylindrical body 26 protruding from the side surface of the calcining furnace 4 of No. 8, and the end of the second duct 21 on the dust settling chamber 18 side is fitted into the cylindrical body 26 so as to be relatively movable.
In this case, by setting the dimensions indicated by symbols A and B in FIG. 1 to predetermined values, it is possible to cope with a large amount of expansion and contraction of the second duct 21 in the axial direction.

Further, an air seal device 27 is provided to seal the fitting portion between the cylindrical body 26 and the second duct 21. Flange 27a of this air seal device 27
has a long hole 2 extending in the radial direction of the second duct 21.
8 is formed, and the bolt 2 passes through this elongated hole 28.
9, the flange 27a is attached to the flange 26a of the cylindrical body 26. In this case, if the dimension indicated by the symbol C in FIG. 1 and the length of the long hole 28 are set to predetermined values, both the flanges 26a,
Relative sliding in the radial direction of 27a is possible,
Air seal device 27 associated with the second duct 21
Thus, relative movement of the cylindrical body 26 in the radial direction is permitted. In addition, the second duct 21 and the cylindrical body 26
Seal air supplied from an air seal device 27 is blown into the gap between the air seal and the air seal, and this seal air prevents clinker dust contained in the discharged air from the air duct 17 from accumulating in the gap. Therefore, clinker dust is both dust 2
Because the clinker dust is not compressed in the gap due to the expansion and contraction of 0 and 21, both dust 20 and 2
The expansion and contraction of 1 is not inhibited. Furthermore, the air seal device 27 is provided with a sealing material 30 that is slidably pressed against the outer peripheral surface of the second duct 21, thereby preventing the seal air of the air seal device 27 from leaking to the outside.

32 is a refractory that protects the iron skin of each device, and 33 is an air lock damper.

FIGS. 4 and 5 show second and third embodiments, respectively, and the basic configuration is the same as that of the first embodiment. Therefore, the same components are given the same reference numerals, and the explanation thereof will be omitted.

FIG. 4 shows a second embodiment. In this configuration, the end of the second duct 21 on the dust settling chamber 18 side is a double cylindrical portion composed of an inner and outer cylinder 35, 36,
This double cylindrical portion is fitted into the cylindrical body 26 of the dust settling chamber 18. Moreover, the inner cylinder 35 in the double cylinder part
Air is forcibly blown into the gap between the outer cylinder 36 and the outer cylinder 36 (indicated by arrow E in the figure). This cools the double cylindrical portion, which prevents the end of the second duct 21 on the dust settling chamber 18 side from being thermally deformed, and also makes it possible to use low-grade material for the end of the second duct. be able to.

In the above case, the double cylinder portion of the second duct 21 may not be forcibly cooled by air, but may be cooled naturally.

FIG. 5 shows a third embodiment. In this configuration, the dust settling chamber 18 is not provided in the air duct 17,
The divided end of the first duct 20 has a cylindrical body 26 . In this case, any desired one of the duct supports 24b of the second duct 21 is fixed, and the others are made slidable, so that the second duct 21 on the calcining furnace 4 side than the fixed duct support 24b is fixed.
The expansion joint 23 according to this embodiment may be used as a measure against thermal expansion.

In each of the above embodiments, the first duct 20 is connected to the air outlet of the cooler 2, and the second duct 21 is connected to the air inlet of the calciner 4, but this is the opposite. The first duct 20 may be connected to the calcining furnace 4 and the second duct 21 may be connected to the cooler 2.

(Effects of the invention) The effects of this invention are as follows. That is,
The powder raw material firing equipment has a firing furnace that fires the powder raw material and a cooler that cools the fired product discharged from the firing furnace with an air flow. A calciner is disposed upstream of the calciner, and the air outlet of the cooler is connected to the calciner through an air duct, and the air discharged from the cooler is used to supply fuel in the calciner. If the powder raw material is calcined in a calcining furnace using the hot gas generated by the combustion, the dimensions of the air duct are long due to its configuration.
This air duct expands and contracts significantly due to the high temperature exhaust air from the cooler that cools the baked product. Therefore, in this invention, the air duct is divided in the middle, and the air duct is composed of at least a first duct and a second duct, and the divided end of the second duct is connected to the divided end of the first duct in the axial and radial direction. Since the first duct and the second duct are fitted so as to be relatively movable in the direction, and a sealing material is interposed between the two ducts at the fitting portion of the two ducts, large expansion and contraction of the air duct causes the first duct and the second duct to move relative to each other. It is permissible to do so. Therefore, there is no need for a large number of expansion joints to accommodate the large amount of expansion and contraction of the air duct, unlike in the past.
Furthermore, since the number of expansion joints can be reduced, the number of duct supports that support the air ducts at the positions between the expansion joints can be reduced, and as a result, the firing apparatus can have a simple structure as a whole.

[Brief explanation of drawings]

1 to 5 show the first to third embodiments of this invention, and FIGS. 1 to 3 show the first embodiment.
The figure is a partial enlarged sectional view of Figure 3, Figure 2 is a system diagram of the powder raw material firing apparatus, Figure 3 is a lower side view of the firing apparatus, and Figures 4 and 5 are the second and third embodiments, respectively. A diagram corresponding to FIG. 1 and FIG. 6, respectively, show a conventional example and are partial side sectional views of an air duct. 1...Calcination furnace, 2...Cooling machine, 4...Calcination furnace,
17... Air duct, 20... First duct, 21
... Second duct, 23 ... Expansion joint, 27 ... Air seal device, 30 ... Sealing material.

Claims (1)

[Scope of utility model registration request] A firing furnace for firing the powder raw material and a cooler for cooling the fired product discharged from the firing furnace with an air flow are provided, and the powder raw material is preheated on the upstream side of the firing furnace when viewed in the flow direction of the powder raw material. A preheating device and a calciner are provided, the cooler is connected to the calciner through an air duct, and the exhaust air from the cooler passes through the air duct to burn fuel in the calciner, and the combustion produces In a powder raw material calcination device in which the preheated powder raw material is calcined in a calcining furnace using hot gas, the air duct is divided in the middle and the air duct is composed of at least a first duct and a second duct. Then, the divided end of the second duct is fitted into the divided end of the first duct so as to be relatively movable in the axial and radial directions, and a sealing material is interposed between the two ducts at the fitting part of these two ducts. An expansion joint for a powder raw material firing device characterized by: