JPS6349532B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust removal device for removing dust from dust-containing gas, and more particularly to a dust removal device that uses a porous ceramic tube and is suitable for processing high-temperature dust-containing gas.

BACKGROUND ART Various devices have been put into practical use as devices for removing dust from dust-containing gas. However, it has been difficult to remove dust from high-temperature dust-containing gas with high dust removal efficiency without lowering the temperature. For example, in a bag filter, the dust-containing gas temperature is approximately
The temperature must be below 250℃, and electrostatic precipitators cannot be used unless the temperature is approximately 350℃ or below, and although cyclones can be applied to relatively high-temperature dust-containing gases, they can only remove dust with fairly large particle sizes.
Dust removal efficiency remains at about 90%.

On the other hand, it has been known for a long time that clean gas can be obtained by passing dust-containing gas through a porous ceramic tube.
And it is put into practical use. It is also well known that porous ceramic tubes have excellent heat and corrosion resistance. Therefore, as an industrial-scale device that continuously removes dust from large amounts of high-temperature dust-containing gas discharged from industrial equipment such as electric furnaces and converters, we have installed ceramic porous pipes that are installed vertically. , a dust removal device has been proposed that includes a tube sheet that supports the end of the tube via a sealing material, and a can body that houses the tube and the tube sheet and is provided with a dust-containing gas inlet and a clean gas outlet. Ru.

In such dust removal devices using porous ceramic tubes, steel or other metal materials are often used for the can body due to strength requirements, and therefore the coefficient of thermal expansion is large. Quality tubes generally have a small coefficient of thermal expansion. Therefore, when this dust removal device is applied to high-temperature dust-containing gas, a difference in thermal expansion occurs, which causes the vertical position of the tube plate that should support the porous tube to change from the predetermined support position of the porous tube. This may cause problems such as not being able to form the desired seal, causing breakage or falling off of the porous tube, and causing cracks or damage to various parts of the device.

An object of the present invention is to provide a dust removal device using a porous ceramic tube that can be applied to high-temperature dust-containing gases, in which the difference in expansion and contraction caused by the difference in thermal expansion coefficient between the porous ceramic tube and the can body can be alleviated. It is an object of the present invention to provide a dust removal device capable of eliminating inconveniences.
Further, other objects of the present invention will become apparent from the following description.

The present invention provides an upright ceramic porous tube, a tube sheet that supports the end of the tube via a sealing material, and a tube sheet that accommodates the tube and the tube sheet, as well as a dust-containing gas inlet and a clean gas outlet. In a dust removal device having a can body, members fixed to the tube sheet and extending outside the can body are fixed to each other outside the can body, and an inflatable member is provided in the can body between the tube sheets. This is a dust removal device characterized by being provided with.

EMBODIMENT OF THE INVENTION Hereinafter, the dust removal apparatus of this invention will be explained in detail based on the drawing of an Example.

As shown in FIGS. 1 and 2, this dust removal device is constructed by housing a plurality of ceramic porous tubes 2 in a can body 1. As shown in FIGS. In the illustrated example, the can body 1 has a cylindrical shape, but is not limited to this, and may have a rectangular tube shape, for example. Further, the porous tube 2 is also cylindrical and easy to manufacture, but is not limited to this, and may have a rectangular tube shape, for example. The porous tube 2 is manufactured by molding and sintering ceramic powder. The ceramic material is mullite, which has excellent thermal shock resistance.
Cordierite, silicon carbide, silicon nitride, etc. are preferable. Generally, the length of the porous tube 2 is preferably longer, but it is approximately 0.5 in consideration of improving yield during molding and sintering, preventing deformation, and strength during use.
~2m.

A plurality of porous tubes 2 (three in the example) are connected in series to form a long tube, and a plurality of rows (21 rows in the example) of these long tubes are erected in parallel in the can body 1. ing. This group of long tubes is supported by the tube plate 3 via the sealing material 4 at both its upper and lower ends and at the connecting portion, that is, at the end of each porous tube 2 . tube plate 3
The peripheral edge of the tube is fixed to the can body 1, and a required number of holes into which the porous tube 2 is inserted are bored.

A part which is a support part of the porous tube 2 by the tube plate 3;
Part B is shown enlarged in FIGS. 3 and 4, respectively.
FIG. 3 shows the connection part of the porous tube 2,
The tube sheet 3, which is provided with a heat insulating material layer 5 on both sides to prevent heat loss and protect the tube sheet, is provided with a coolant passage 6 inside. 3 and the sealing material 4 are thermally protected. The hole size of the tube sheet 3 is made large enough to allow the porous tube 2 to be inserted loosely, and a sealing material 4 is inserted between the porous tube 2 and the tube sheet 3, so that the porous tube 2 is inserted into the tube sheet 3. While being supported, the connection portion of the porous tube 2 is sealed, and the upper and lower sides of the tube sheet 3 are also sealed. The sealing material 4 does not need to block the passage of gas, and may be any material that substantially blocks the passage of dust. It is also desirable to have heat resistance against high-temperature gases, and ceramic fiber ropes, carbon fiber gland packings, metal fiber ropes such as stainless steel, etc. are used.
The method of supporting the upper end of the long pipe is almost the same. FIG. 4, which shows the lower end of the long tube, is substantially the same except that an annular rib 11 is formed on the inner circumferential surface of the hole in the tube plate 3 to support the lower end of the long tube.

A dust-containing gas inlet 12 is attached to the part of the can body 1 above the top tube sheet 3, and the part of the can body 1 below the bottom tube sheet 3 forms a hopper 13. A dust discharge port 14 is attached to the lower part, and a dust-containing gas extraction port 15 is provided at the side of the hopper 13 as required. Although not shown, a clean gas outlet is provided in the can body 1 between the uppermost tube sheet 3 and the lowermost tube sheet 3. When a communicating hole is provided in the intermediate tube sheet, there should be at least one clean gas outlet, and if each tube sheet is not provided with a communicating hole, one can body between adjacent tube sheets is required. Each is provided with a clean gas outlet. A heat insulating material layer 5 is also formed on the inner surface of the can body 1 as required to prevent heat loss.

When high-temperature dust-containing gas is introduced into this dust removal device from the dust-containing gas inlet 12, the dust-containing gas enters each long pipe, passes through the permeable porous pipes 2 that constitute the long pipes, and becomes a clean gas. passes through the wall of the porous tube 2 and is taken out to the clean gas outlet. On the other hand, the dust separated from the dust-containing gas coagulates with each other and descends mainly along the inner wall of the porous tube 2 due to its weight and the kinetic energy of the dust-containing gas, and accumulates in the hopper 13. In addition, the dust outlet 14
is closed at all times and is opened intermittently to vent dust. Further, if necessary, a part of the supply gas may be extracted from the dust-containing gas extraction port 15 in order to impart downward kinetic energy to the separated dust, particularly the dust at the lower part of the long pipe.

Since the porous tube 2 is supported by the tube plate 3 via the sealing material 4, vibrations are alleviated and there is little possibility that the porous tube 2 will be damaged. Further, the difference in thermal expansion between the tube plate 3 and the porous tube 2 in the horizontal direction is absorbed by the sealing material 4. However, the vertical position of the tube plate 3 must be at both the upper and lower ends of the long tube and at the connecting portion.
In other words, if the vertical position of the tube sheet deviates from this position, the porous tube 2 may come into direct contact with the tube sheet 3 or its heat insulating material layer 5, damaging the porous tube or preventing dust from being sealed. This may cause inconveniences such as failure or the sealing material falling off. Especially when processing high-temperature dust-containing gas, tube sheet 3
The can body 1 supporting the can body 1 or its heat insulating material layer 5 generally has a large coefficient of thermal expansion, while the porous tube 2 is made of ceramics, particularly ceramics with excellent thermal shock resistance, and therefore has a small coefficient of thermal expansion. At high temperatures, the difference in thermal expansion increases, which may lead to the above-mentioned problems.

Therefore, in the dust removal device of the present invention, the tube sheets 3 are held together by means that are not affected by temperature etc., and the interval between them is kept constant.
An expansion allowance 9 is provided to prevent damage to the That is, the horizontal member 7 is fixedly attached to the tube plate 3,
This horizontal member 7 extends outside the can body 1, preferably to a position substantially unaffected by the heat of the can body 1. In this position, the horizontal member 7 is fixed to the vertical member 8. Although it is desirable that the interval between each horizontal member 7 be equal to the interval between each tube sheet 3, it is not necessarily limited to this. In this way, since the members that are firmly attached to the tube sheet 3 and extend outside the can body 1 are fixed to each other outside the can body 1, these members are made of metal or other material with a relatively large coefficient of thermal expansion. Even if it is made of a material, the temperature is much lower than that inside the can body 1.
Therefore, the amount of thermal expansion in the vertical direction becomes substantially equal to that of the porous tube 2, and there is no possibility that each tube sheet 3 will shift from its predetermined position.

In addition, in the illustrated embodiment, as shown in detail in FIG. is used as an expansion ring 9, and the gap between the expansion ring 9 is connected with an expansion ring 10 such as an annular semicylindrical Adamson joint. Telescopic ring 10
covers the expansion margin 9 provided in the can body 1 and prevents gas from flowing out of the can body 1. Even if the temperature of the can body 1 rises and the expansion margin 9 narrows, the expansion ring 10 Follow this by bending further. Note that the shape and structure of the expansion allowance 9 are not limited to those described above, and various forms can be adopted, and the expansion ring 10 may be replaced with other suitable joints.

In addition, in the above explanation, the case where a long pipe with porous pipes connected was explained, but the same applies to the case where a single stage porous pipe without a connecting part is used, and the present invention also applies. It is included.

Since the dust removal apparatus of the present invention is constructed and operates as described above, it can be effectively used as an apparatus for removing dust from high-temperature dust-containing gas on an industrial scale and obtaining high-temperature clean gas. In particular, since a porous ceramic tube is used for the dust removal member, high-temperature gas can be processed as is, and thermal energy can be recovered with high efficiency. In addition, in the device of the present invention, even if the can body is made of a metal material such as steel, the influence of the difference in thermal expansion coefficient between the metal material and the ceramic porous tube is alleviated, and failures caused by temperature changes, especially ceramics, are reduced. Accidents such as damage to porous pipes are prevented. Furthermore, since it has been subjected to anti-vibration treatment, there is less risk of accidents due to earthquakes, equipment vibrations, etc. Therefore, the device of the present invention has great industrial utility value.

[Brief explanation of the drawing]

FIGS. 1 and 2 are longitudinal sectional views and cross sectional views of essential parts of an embodiment of the dust removal device of the present invention, and FIGS. 3, 4, and 5 are section A, B, and It is an enlarged view of part C. DESCRIPTION OF SYMBOLS 1... Can body, 2... Porous tube, 3... Tube sheet, 4... Sealing material, 5... Heat insulating material layer, 7... Horizontal member, 8... Vertical member, 9... Expansion.

Claims (1)

[Claims] 1 An upright ceramic porous tube, a tube sheet that supports the end of the tube via a sealing material, and a tube sheet that accommodates the tube and the tube sheet and is provided with a dust-containing gas inlet and a clean gas outlet. In a dust removal device comprising a can body, members fixed to the tube sheet and extending outside the can body are fixed to each other outside the can body, and an expansion allowance is provided in the can body between the tube sheets. A dust removal device characterized by: