JP2000237518A - Gas filter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas filter device capable of being constituted of an inexpensive structural material and recovering heat of clean gas. SOLUTION: A cylindrical inner cylinder 3 is disposed at the inside of an outer cylinder 2 having a cylindrical body part, and cylindrical ceramic filters 10 are radially arranged in multi-stages and fixed on the wall surface of the outer cylinder 2 and the wall surface of the inner cylinder 3, and boiler water tubes 22 are arranged along the inner wall of the inner cylinder 3. Exhaust gas is introduced into an internal space between the outer cylinder 2 and the inner cylinder 3 from a gas introduction port 7, and is passed through the inside of the ceramic filters 10 to be made into clean gas, and the clean gas is introduced into an internal space of the inner cylinder 3 and is cooled with cooling water flowing through the boiler water tubes 22, and is discharged from a gas discharge port 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas filter device for treating high-temperature exhaust gas containing dust generated in a waste incinerator, an incineration ash melting furnace, and the like.

[0002]

2. Description of the Related Art Conventionally, when collecting exhaust gas containing dust generated from a waste incinerator or an incineration ash melting furnace, an electric dust collector or a bag filter has been mainly used. However, in recent years, problems such as re-synthesis of dioxin have been pointed out in electric precipitators, and bag filters have been frequently used. However, when using this bag filter, it is necessary to reduce its temperature to about 150 ° C. to 200 ° C. before introducing the exhaust gas into the bag filter due to the limited heat resistance.

Recently, a porous ceramic filter having heat resistance has been developed and put into practical use as a filter applicable to high-temperature gas. This ceramic filter is solid and has a through hole of 10 to 20 μm, and the dust in the exhaust gas is removed by passing the exhaust gas through it. It is possible to

FIG. 5 shows a schematic structure of a typical dust collector using a ceramic filter (the same structure as a conventional bag filter). As shown in the figure, in this dust collector 50, a rod-shaped or plate-shaped ceramic filter 51 is vertically suspended on a partition wall 53 provided at an upper portion of a casing 52, and a gas inlet 54 is provided at a lower portion of the casing 52. A gas outlet 55 is provided at an upper portion of the casing 52. Further, a pulse tube 56 is provided for removing dust adhering to the outer surface and the pores of the ceramic filter 51. Here, the length of the ceramic filter 51 is set to about 1 to 2 m, which is relatively easy to handle and maintain.

In the dust collector 50 constructed as described above, the exhaust gas is introduced into the casing 52 through the gas inlet 54, the dust is removed by passing through the pores of the ceramic filter 51, and the dust is removed from the top of the casing 52. And is discharged from the gas outlet 55 as a clean gas. When the exhaust gas passes through the ceramic filter 51, dust adheres to the outer surface and the pores of the ceramic filter 51 to cause clogging. Therefore, the pulse tube 56 for removing dust periodically removes air. The dust is caused to flow backward in the pores of the ceramic filter 51 while applying a pulse, so that the dust falls to the bottom of the casing 52. The dust accumulated at the bottom of the casing 52 is discharged by a conveyor 57 disposed at the bottom.

However, in the dust collector 50 having the structure shown in FIG. 5, the length of the ceramic filter is about 1 to 2 m.
Since the amount of exhaust gas per unit is small, it is necessary to increase the number of ceramic filters in order to increase dust collection efficiency. On the other hand, due to the design and installation area of the dust collector, the size of one dust collector, in other words, its exhaust gas treatment capacity is limited, and when performing large-capacity exhaust gas treatment, the number of dust collectors must be reduced. It is necessary to increase. That is, a plurality of dust collection bases are installed in parallel, and on account of the installation area,
It is necessary to set up vertically. Also,
With the installation of a plurality of such dust collectors, a plurality of dust carrying devices are required.

In order to cope with such a problem, it is conceivable to increase the length of one ceramic filter to, for example, about 3 to 5 m to increase the exhaust gas treatment capacity per dust collector. In this case, handling and maintenance of the ceramic filter become difficult. In other words, since the filter is fixed at the upper end, the ceramic filter can be fixed when the filters come into contact with each other due to the gas flow or vibration when the filter is removed, the filter is damaged, the dust collector is overhauled, or the ceramic filter is replaced. In addition to the fact that the part is inside the casing, the ceramic filter must be lifted vertically upward by the length of the ceramic filter, and the necessary working space must be secured at the top of the device. is there.

In order to solve the above-mentioned problem, the applicant of the present invention has disclosed in Japanese Patent Application No. 10-330568 a method in which a cylindrical inner cylinder is provided inside an outer cylinder having a cylindrical body, and the wall surface of the outer cylinder is provided. A cylindrical ceramic filter is arranged radially and in multiple stages on the wall of the inner cylinder and fixed, and the exhaust gas is introduced into the inner space between the outer cylinder and the inner cylinder, and the inner space of the inner cylinder is passed through the inside of the ceramic filter. We propose a gas filter device that discharges gas from the system.

[0009]

However, in the gas filter device according to the present invention, the exhaust gas introduced into the internal space between the outer cylinder and the inner cylinder has a high temperature and passes through the ceramic filter through the inner cylinder. Since the temperature of the clean gas passing through the internal space is high, the inner cylinder needs to be made of a material having high heat resistance, which causes a problem that the cost increases.

Further, since the clean gas passing through the internal space of the inner cylinder is recovered at a high temperature, it is necessary to provide a heat recovery facility downstream of the gas filter device, and the necessary space must be secured. In addition to the problem that must be solved, there is a problem that this also increases the cost.

The present invention has been made in order to solve such a problem, and provides a gas filter device which can be formed of an inexpensive structural material and can simultaneously recover heat of a clean gas. The purpose is to do so.

[0012]

In order to achieve the above-mentioned object, a gas filter device according to a first aspect of the present invention comprises an outer cylinder having a cylindrical or polygonal body and an inner cylinder inside the outer cylinder. A casing having a cylindrical or polygonal inner cylinder provided on the outer cylinder, one end of which is fixed to the wall surface of the outer cylinder and the opening thereof is closed, and the other end is fixed to the wall surface of the inner cylinder. A cylindrical ceramic filter whose opening is open to the inner space of the inner cylinder; a gas inlet for introducing exhaust gas into the inner space between the outer cylinder and the inner cylinder; and a dust inlet after removing dust from the inner space of the inner cylinder. And one or a plurality of boiler water pipes through which cooling water flows along the inner wall of the inner cylinder.

In the first invention, exhaust gas containing dust is introduced from the gas inlet into the inner space surrounded by the outer cylinder and the inner cylinder, and passes through the pores of the cylindrical ceramic filter disposed in the inner space. Then, the dust passes through the inside of the ceramic filter, is filtered, becomes a clean gas, and is introduced into the inner cylinder through the opening of the ceramic filter. The clean gas introduced into the inner cylinder is cooled to a low temperature by cooling water flowing in a boiler water pipe provided along the inner wall of the inner cylinder, and is discharged to the outside from the gas outlet. The dust accumulated on the outer surface and the pores of the ceramic filter is backwashed as necessary.

According to the first invention, the cooling water in the boiler water pipe disposed along the inner wall of the inner cylinder recovers the heat of the clean gas and also recovers the heat of the inner cylinder itself. It is not necessary to use a high heat-resistant material, and the inner cylinder can be formed with an inexpensive structural material. Therefore, there is an effect that the cost can be reduced. In addition, since the clean gas in the inner cylinder can be discharged from the gas outlet at a low temperature with a simple configuration, it is not necessary to install a heat recovery facility conventionally required downstream of the gas outlet. In addition, there is an effect that the restriction on space can be eliminated and the entire device can be downsized. Further, the cost can be reduced accordingly.

Next, the gas filter device according to the second invention is formed by an outer cylinder having a square cylindrical body and two flat plates arranged substantially parallel to two opposing surfaces of the outer cylinder. A casing having an inner cylinder, one end of which is fixed to the wall surface of the outer cylinder and the opening thereof is closed, and the other end of which is fixed to the wall surface of the inner cylinder and the opening is formed in the inner space of the inner cylinder. An open cylindrical ceramic filter, a gas inlet for introducing exhaust gas into an internal space between the outer cylinder and the inner cylinder, and a gas outlet for extracting clean gas after dust removal from the inner space of the inner cylinder. And one or more boiler water pipes through which cooling water flows are provided along the inner wall of the inner cylinder.

In the second invention, as in the first invention,
Exhaust gas containing dust is introduced from the gas inlet into the internal space surrounded by the outer cylinder and the inner cylinder, and passes through the inside of the ceramic filter through the pores of the cylindrical ceramic filter arranged in this internal space. The dust is filtered and becomes a clean gas, which is introduced into the inner cylinder through the opening of the ceramic filter. The clean gas introduced into the inner cylinder is cooled to a low temperature by cooling water flowing in a boiler water pipe provided along the inner wall of the inner cylinder, and is discharged to the outside from the gas outlet. Thus, the same effect as the first invention can be obtained.

In each of the above inventions, the boiler water pipe is
It is preferable that the gas passage is formed so as to be at least partially embedded between openings of the gas passage formed in the inner cylinder. By doing so, the temperature of the clean gas can be reduced more reliably, and heat recovery of the inner cylinder can be performed.

[0018]

Next, a specific embodiment of a gas filter device according to the present invention will be described with reference to the drawings.

FIG. 1 shows a horizontal sectional view (a), an outer shape (left half) and a vertical sectional view (right half) (b) of a gas filter device according to one embodiment of the present invention, and FIG. Figure 1
2A shows a partially enlarged view (a) and FIG. 1B shows a partially enlarged view (P section enlarged view) (b).

The gas filter device 1 of this embodiment includes a casing 4 having an outer cylinder 2 having a cylindrical body and a cylindrical inner cylinder 3 provided concentrically inside the outer cylinder 2. I have. In order to define an internal space surrounded by the outer cylinder 2 and the inner cylinder 3, the casing 4
However, annular hoppers 6 each having an inverted triangular cross section are provided at the lower part, and a gas introduction port 7 for introducing exhaust gas is formed in a part of the lid 5. Similarly, in order to define an internal space of the inner cylinder 3, a lid 8 is provided at a lower portion, and a gas outlet 9 for leading a clean gas is provided at an upper portion. Although not shown in the figure, a conveyor (for example, a screw conveyor) for discharging dust is disposed below the annular hopper 6.

A plurality of cylindrical (or square) ceramic filters 10 are arranged between the outer cylinder 2 and the inner cylinder 3. These ceramic filters 10 are arranged radially in the horizontal direction about the center axis of the inner cylinder 3 and in multiple stages in the vertical direction. In the case of the present embodiment, 18 ceramic filters 10 are arranged in two stages in the vertical direction.
A total of 450 ceramic filters 10 arranged in 5 stages
Is stored.

As shown in FIG. 2, the ceramic filter 10 has one end (outer end) whose opening is closed by a plug 11 and only the other end (inner end) opened. Has been. In the fixing portion of the ceramic filter 10, a through hole 12 is formed in the wall of the outer cylinder 2, and a gas passage 13 having substantially the same diameter as the inner diameter of the ceramic filter 10 is formed in the wall of the inner cylinder 3. The outer end of the gas passage 13 has a slightly larger diameter, and the other end of the ceramic filter 10 is fitted and fixed to the larger diameter.

Four stud bolts 14 are provided upright on the outer surface of the outer cylinder 2 at positions surrounding the through holes 12.
A plate-like body 15 is fixed to the tip of the stud bolt 14 with a nut 16. A first compression coil spring 17 is stretched between the inner surface of the plate-like body 15 and the distal end of the plug 11, and the first compression coil spring 17 passes through the plug 11 through the ceramic filter 10. Is pressed against the outer wall surface of the inner cylinder 3.
In order to seal a gap formed between the ceramic filter 10 and the through hole 12, a sealing material 18 is packed into the gap from the outside.
The annular body 20 fitted on the outer peripheral surface of the ceramic filter 10 by the urging force of the second compression coil spring 19
Is pressed through the switch.

When assembling the ceramic filter 10, the plug 11, the plate 15, the compression coil springs 17 and 19, and the annular body 20 are attached to one end of the ceramic filter 10. The other end of the ceramic filter 10 is inserted into the through hole 12 of the outer cylinder 2, and a sealing member 18 is packed in a required portion, and the other end of the ceramic filter 10 is pressed against the large diameter portion of the gas passage 13 of the inner cylinder 3. Thereafter, the compression coil springs 17 and 19 are compressed, and the plate 15 is fixed to the stud bolt 14 with the nut 16. On the other hand, when removing the ceramic filter 10 for replacement, the nut 16 is loosened and the ceramic filter 10 is pulled out together with the plug 11, the plate 15, the compression coil springs 17, 19 and the ring 20. Become.

In this embodiment, pulse tubes 21 are provided in the space inside the inner cylinder 3 so as to face the gas passages 13, and air for backwashing is supplied from the pulse tubes 21 to the individual ceramic filters 10. It is supposed to be.
In this way, dust adhering to the outer surface and the pores of the ceramic filter 10 is regularly backwashed. Further, between the pulse pipes 21 and 21 arranged in the inner space of the inner cylinder 3,
In other words, a plurality of boiler water pipes 22 are provided between the gas passages 13 and 13 and partially embedded in the inner wall of the inner cylinder 3, and cooling water flows through the boiler water pipes 22.

In the gas filter device 1 configured as described above, when the exhaust gas containing dust is introduced from the gas inlet 7 into the internal space surrounded by the outer cylinder 2 and the inner cylinder 3, the exhaust gas is The dust enters the inside of the ceramic filter 10 through the pores of each ceramic filter 10, and the dust is filtered to become a clean gas through the gas passage 13 from the inner end, which is the open end of the ceramic filter 10. It is introduced into the internal space of the cylinder 3. Although the clean gas introduced into the inner cylinder 3 is hot, the boiler water pipe 22
The cooling water flowing inside recovers the heat, and the cooling water becomes hot water or steam, and lowers the temperature of the clean gas. This clean gas is discharged from the inside of the inner cylinder 3 to the outside of the system via the gas outlet 9.

The dust in the exhaust gas is accumulated on the outer surface and in the pores of the ceramic filter 10 and is backwashed by the air periodically sent from the pulse tube 21. The dust generated by the backwashing is collected in an annular hopper 6 disposed below the inner space between the outer cylinder 2 and the inner cylinder 3, and is discharged out of the system by a dust carrying conveyor.

According to the gas filter device 1 of the present embodiment, the cooling water in the boiler water pipe 22 arranged along the inner wall of the inner cylinder 3 recovers the heat of the inner cylinder 3 itself. It is not necessary to use a heat-resistant material, and the inner cylinder 3 can be formed with an inexpensive structural material. Therefore, there is an effect that the cost can be reduced.

Further, according to the present embodiment, the clean gas in the inner cylinder 3 is discharged from the gas outlet 9 to the outside of the system at a low temperature with a simple configuration in which the boiler water pipe 22 is installed in the gas filter device 1. The gas outlet 9
This eliminates the need for installing a heat recovery facility that has been conventionally required on the downstream side of the apparatus, and has the effect of eliminating space restrictions and reducing the size of the entire apparatus. Also,
This brings about an effect that the cost can be reduced.

In this embodiment, the outer cylinder 2 and the inner cylinder 3 are formed in a cylindrical shape. However, as shown in FIG. 3, the outer cylinder 2 'and the inner cylinder 3' are formed in a square cylinder. You may. In this case, the ceramic filters 10 are arranged horizontally and in parallel on opposing surfaces of the outer cylinder 2 'and the inner cylinder 3', and are arranged in multiple stages in the vertical direction. Also,
The boiler water pipe 22 is inserted between the ceramic filters 10 and 10 so as to be partially embedded in the inner wall of the inner cylinder 3 ′.
Is provided. Since there is basically no difference from the above-described embodiment in the configuration, operation, and the like, a detailed description thereof will be omitted. Note that FIG.
In the example shown in (1), the cross-sectional shape of the outer cylinder 2 'and the inner cylinder 3' is square, but this cross-sectional shape may be rectangular. Further, the outer cylinder and the inner cylinder are not limited to square cylinders, and may be other polygonal cylinders.

FIG. 4 shows still another embodiment of the present invention. In this embodiment, the outer cylinder 2 "is formed as a square cylinder, and the inner cylinder 3" is formed of two flat plates so as to penetrate two opposing surfaces of the outer cylinder 3 ". Numeral 10 is provided horizontally and in multiple stages on opposing surfaces of the outer cylinder 2 "and the inner cylinder 3". Further, a part is embedded in the inner wall of the inner cylinder 3 "between the ceramic filters 10, 10. A boiler water pipe 22 is provided so that the boiler water can be removed. There is no difference in the configuration, operation, and the like other than those of the above-described embodiments. In the case of the present embodiment, in order to increase the amount of exhaust gas to be processed per gas filter device, the number of stages of the ceramic filter 10 may be increased to increase the height, or the number of rows may be increased. You may do it.

Further, in each of the above-described embodiments, the boiler water pipe 22 is installed so as to be partially embedded in the inner wall of the inner cylinder 3 (3 ′, 3 ″).
(3 ′, 3 ″) may be arranged so as to be in contact with the inner wall.

[Brief description of the drawings]

FIG. 1 is a view showing a gas filter device according to an embodiment of the present invention, wherein (a) is a horizontal sectional view and (b)
Is an external view and a vertical sectional view.

FIGS. 2A and 2B are FIGS. 1A and 1B, respectively.
FIG.

FIG. 3 is a horizontal sectional view of a gas filter device according to another embodiment of the present invention.

FIG. 4 is a horizontal sectional view of a gas filter device according to still another embodiment of the present invention.

FIG. 5 is a diagram showing a conventional dust collector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas filter apparatus 2, 2 ', 2 "Outer cylinder 3, 3', 3" Inner cylinder 4 Casing 5 Lid 6 Annular hopper 7 Gas inlet 8 Lid 9 Gas outlet 10 Ceramic filter 11 Plug 12 Through hole Reference Signs List 13 gas passage 14 stud bolt 15 plate 16 nut 17 (first) compression coil spring 18 sealing material 19 (second) compression coil spring 20 annular body 21 pulse tube 22 boiler water tube

Continued on the front page (72) Inventor Ryoji Samejima 2-2-233 Kinrakuji-cho, Amagasaki City, Hyogo Prefecture Inside of Takuma Co., Ltd. (72) Inventor Eiichi Ukai 6 Kyocera Corporation, Takeda Toba-cho, Fushimi-ku, Kyoto-shi (72) Inventor Shinichi Yamaguchi 1-1, Yamashita-cho, Kokubu-shi, Kagoshima Kyocera Corporation Kagoshima Kokubu Plant F term (reference) 4D019 AA01 BA05 BB01 BC12 CA03 CB01 CB04 4D058 JA02 JB06 JB41 KA03 KB05 LA01 RA12 SA20 UA03

Claims (3)

[Claims] A casing having an outer cylinder having a cylindrical or polygonal body, a cylindrical or polygonal inner cylinder provided inside the outer cylinder, and one end fixed to a wall surface of the outer cylinder. And the opening is closed, and the other end is fixed to the wall surface of the inner cylinder, and the opening is opened to the inner space of the inner cylinder. A gas inlet for introducing exhaust gas into the internal space between the two, and a gas outlet for extracting clean gas after dust removal from the internal space of the inner cylinder, and cooling water flows inside along the inner wall of the inner cylinder. A gas filter device comprising one or a plurality of boiler water pipes. 2. A casing comprising: an outer cylinder having a square cylindrical body; and an inner cylinder formed by two flat plates disposed substantially parallel to two opposing surfaces of the outer cylinder; A cylindrical ceramic filter, which is fixed to the wall surface of the outer cylinder and whose opening is closed, and whose other end is fixed to the wall surface of the inner cylinder and whose opening is opened to the inner space of the inner cylinder, A gas inlet for introducing exhaust gas into the inner space between the outer cylinder and the inner cylinder, and a gas outlet for deriving clean gas after dust removal from the inner space of the inner cylinder, and an inner wall of the inner cylinder. A gas filter device comprising one or a plurality of boiler water pipes through which cooling water flows. 3. The gas filter device according to claim 1, wherein the boiler water pipe is disposed so as to be at least partially embedded between openings of a gas passage formed in the inner cylinder.