JPH1119441A - Particulate trapping device and sealing material therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obviate dust leakage in spite of the presence of moisture, etc., by disposing inorg. mats which are subjected to a waterproof treatment and contain components expanding at the time of heating on the surface side of the frame part of a bored shape frame where the sealing material of a particulate trapping device for regenerating a filter by generating a backflow gas comes into contact with the upper and lower surface filters. SOLUTION: The introduction of the dust-laden gas is stopped in order to remove the particulates captured by the filter 2 and to regenerate the filter 2. A back washing valve 7 near a cleaning gas outflow member is opened to rapidly introduce the back washing gas from an introducing port 8. The back washing gas is sent from the cleaning gas flow passage side via the filter walls to the dust-laden gas flow passage side. The particulates are desorbed from the filter walls and are passed through the dust-laden gas flow passage extending in a longitudinal direction. The particulates are then dropped into a lower particulate receiving section 9 and are ignited and burned to ash by a seal heater 10. The ash is taken out of an ash take-out port 11. The inorg. materials and sealing materials are subjected to a waterproof treatment. As a result, there is no absorption of the moisture and even if there is the moisture in the waste gases and the device, the deterioration of the restoration performance of the inorg. mats is averted and the dust leakage is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a particulate material (particulate dust or soot containing carbon as a main component) contained in exhaust gas of a diesel engine or the like.
The present invention relates to a trap device and a seal material for the trap device.

[0002]

2. Description of the Related Art Diesel engine exhaust gas (approximately 50
(0 ° C), the particulates have a considerable concentration (15
0-250 mg / Nm ³ ), causing pollution. Therefore, a particulate trap device that captures and removes particulates from exhaust gas of a diesel engine or the like is used.

In a particulate trap device, for example, a rectangular parallelepiped filter is held in the main body of the device, and exhaust gas containing the particulates is passed through the filter to remove the particulates and discharge as a clean gas. Is what you do. A seal material is provided at a position where the filter is held in the apparatus main body in order to prevent the exhaust gas from directly moving to the clean gas space without passing through the filter from the dust-containing gas space into which the exhaust gas is introduced. Is arranged.

Further, the particulate matter accumulated in the filter
In order to remove the filter and regenerate the filter, a backwashing regeneration method of flowing a high-pressure backflow gas from the clean gas space side to separate the particulate from the filter material has been widely performed.

[0005] The seal material is exposed to vibration or high temperature due to exhaust gas during the purification operation, and is exposed to high reverse pressure during regeneration by the introduction of high-pressure backflow gas from the clean gas space side. Therefore, it is required that the seal material does not come off due to vibration, does not deteriorate the material due to high temperature, and is not damaged or blown off by the backflow gas.

For this reason, various seal materials have been proposed. For example, in a gap between the side of the filter and the side wall of the device at the location of the device main body holding the filter, a seal material is arranged so as to be sandwiched by a stopper provided on the side wall of the device, and the dust-containing gas space is provided. And a clean gas space, or a groove is provided on the side of the filter so that a portion of the seal material can enter therein (Japanese Patent Laid-Open No. 3-168313).

A hollow frame-shaped sealing material which is disposed on the upper and lower peripheral portions of a rectangular parallelepiped filter has also been proposed (Japanese Patent Application No. 8-103927). This seal material has a hollow shape corresponding to the shape of the periphery of the upper surface and the lower surface of the filter.
A cross-flow type filter is used in which the dust-containing gas flow path extends in the vertical direction and the clean gas flow path extends in the horizontal direction. A clean gas space is provided, and a particulate receiving portion for receiving the particulate falling from the filter during regeneration is provided below.

In this frame-shaped seal material, an inorganic mat is fixed to the upper and lower surfaces of the frame portion of the hollow frame, and one of the inorganic mats is in contact with a metal body portion constituting the apparatus. And the other mineral mat contacts the filter.
As an inorganic mat, in order to have the resilience that the thickness recovers when released from the pressure from the compressed state,
For example, an inorganic fiber containing a component (expanding agent) that expands when heated, such as vermiculite, or a layer made of this fiber to further enhance the restoring force, and an inorganic fiber mainly containing alumina and silica -Layer (ceramic fiber-layer) is used.

[0009]

However, the inorganic mat, especially the inorganic fiber layer mainly composed of alumina and silica, easily absorbs moisture, and the moisture or water-soluble dew condensed in the exhaust gas or in the device. If water containing salt or acid is present, the fiber tension may occur due to the surface tension of the water or the solidification of salt.
Solidified, the restoring performance deteriorated, and dust leakage sometimes occurred.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hollow frame-shaped seal material in which dust does not easily leak even in the presence of moisture and the like, and a particulate trap device using this seal material. .

[0011]

Means for Solving the Problems Particulates of the present invention
In the trap device, a filter having a dust-containing gas flow path and a clean gas flow path partitioned by a filter wall is held in a metal case via a seal material, and passes through the filter wall from the clean gas flow path side. And a filter for regenerating the filter by means of a backflow means for generating a backflow gas flowing to the dust-containing gas flow path, wherein the seal material is provided on the upper and lower surfaces of the frame portion of the hollow frame. At least the surface of the inorganic mat that is waterproofed and that contains a component that expands when heated is disposed on the surface in contact with the filter.

In the present invention, the waterproofed inorganic mat disposed at least on the side contacting the filter is more preferably composed of a laminated mat of an inorganic fiber layer and an inorganic mat layer containing an expansion component. .

The waterproof treatment is performed by a water-repellent treatment with a water-repellent agent, entirely or partially covered with a metal foil or a thin plate, or both. In addition, this waterproof treatment is preferably performed using inorganic fibers.
It is preferable to apply it to the layer.

On the side of the frame portion of the frame that does not come into contact with the filter, a waterproof or non-waterproof inorganic mat containing a component that expands when heated may be arranged.
Further, the frame body may be subjected to a waterproof treatment with a water repellent.

The seal material according to the present invention is an inorganic fiber in which at least the upper and lower surfaces of the upper and lower surfaces of a frame portion having a hollow shape having a shape corresponding to the peripheral portion of the filter are subjected to a waterproof treatment at least on the surface side in contact with the filter. -An inorganic mat comprising a layer and an inorganic mat layer containing a component which expands when heated.

The waterproof treatment of the inorganic fiber layer or the like is performed by a water repellent treatment with a water repellent, the inorganic mat including the inorganic fiber layer is entirely or partially covered with a metal foil or a thin plate, or It is done by using both together. Further, on the side of the frame portion of the frame portion that does not come into contact with the filter, a waterproof or unwaterproofed inorganic mat containing a component that expands when heated may be arranged. Waterproofing may be applied.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the particulate trap apparatus according to the present invention shown in FIG. 1, a rectangular parallelepiped filter 2 is disposed in a metal main body 1. FIG. The filter 2 is made of ceramics, for example, and has a dust-containing gas channel extending in the vertical direction, a clean gas channel extending in the horizontal direction, and a filter between the dust-containing gas channel and the clean gas channel. It is a cross-flow type filter partitioned by walls.

The dust-containing gas is introduced into the dust-containing gas side space 4 from the dust-containing gas inlet 3, and passes through the dust-containing gas passage extending in the filter 2 in the vertical direction. After being removed, the clean gas exits the clean gas space 5 from the laterally extending clean gas channel. The clean gas that has come out is discharged from the clean gas outlet 6.

Particulates captured in the filter 2
Backflow means is used to remove the filter and regenerate the filter 2. That is, the introduction of the dust-containing gas is stopped, the backwash valve 7 provided near the outlet of the clean gas is opened, and the backwash gas (compressed air) is supplied from the backwash gas inlet 8 for a short time (for example, 0. About 3 seconds), and by sending backflow gas from the clean gas channel side to the dust-containing gas channel side through the filter wall,
The particulates are released from the filter wall, and the released particulates fall into the lower particulate receiving portion 9 through the dust-containing gas flow path extending in the vertical direction. The dropped particulates are the sheet heater 1 provided there.
0, it is ignited and burned to ash.
Taken out of Reference numeral 12 denotes an air inlet for burning the particulates. Such reproduction is performed intermittently or as needed.

In the gap between the upper and lower peripheral portions of the filter 2 and the metallic main body 1, seal members 13 and 14 are arranged so that dust does not leak from the dust-containing gas side space to the clean gas space side. ing. As shown in FIG. 2, the sealing members 13 and 14 have a hollow frame shape corresponding to the peripheral portion of the upper surface or the bottom surface of the rectangular parallelepiped filter 2. As shown in FIG.
The inorganic mats 16 and 17 having a hollow shape are fixed to the upper and lower surfaces of the frame portion with an adhesive or the like.

Seal material 1 disposed above filter 2
In the state 3, the upper inorganic mat 16 is pressed against the metal main body 1 and the lower inorganic mat 17 is pressed against the filter 2 as shown in FIG. on the other hand,
In the seal member 14 disposed below the filter 2, the upper inorganic mat is pressed against the filter, and the lower inorganic mat is pressed against the metal main body 1.

The upper inorganic mat 16 is made of inorganic fibers containing a component which expands when heated, and the inorganic fibers are preferably ceramic fibers of alumina / silica type, alumina type, zirconia type or the like. Inorganic fibers such as glass fibers and rock wool may be used, although the corrosion resistance is slightly inferior to the above. Vermiculite is preferably used as a component that expands when heated, and the content of vermiculite is preferably 5% by weight to 40% by weight. If it is less than 5% by weight, the amount of expansion will be insufficient, and if it exceeds 40% by weight, the amount of expansion will be excessive, which is not preferable. Vermiculite is an ore containing structural water, also called vermiculite. When heated, structural water is released at about 400 ° C., and the cleavage surface of the layered crystal is separated and swells to 10 to 30 times its original volume.
This expansion occurs irreversibly, resulting in an expanded body having considerable elasticity. The sealing material utilizes the expansion of the vermiculite due to heating and the holding force due to the elasticity of the expanded body.

In addition to vermiculite, it is also possible to use perlite, acid-treated expanded graphite, synthetic fluorinated mica, foamed plastic (plastic microspheres encapsulating a substance that evaporates at high temperatures) as required, in addition to vermiculite. It is.

The lower inorganic mat 17 comes in contact with the filter 2 whose temperature is higher than that of the metal main body 1,
Inorganic fiber layer 17a having high heat resistance and good elasticity
And an inorganic mat layer 17 containing a component that expands when heated, such as vermiculite, which is the same material as the inorganic mat 16.
What consists of a laminated mat with b is preferable. By using a laminated mat, the elasticity of the inorganic mat can be further increased, and both functions of holding the filter and sealing can be maintained for a long time.

The inorganic fiber layer 17a is preferably a fiber layer mainly composed of silica such as quartz glass or a ceramic fiber layer mainly composed of alumina and silica. In particular, the alumina component contained in the ceramic fiber is preferably contained in an amount of 60% by weight to 80% by weight. If the amount of alumina is less than 60% by weight, the stiffness of the inorganic fiber layer becomes slightly weak, so that the fiber starts to shrink when exposed to high-temperature exhaust gas, and the inorganic fiber layer shrinks. Decrease and see
Performance also decreases. When the alumina component is contained in an amount of 80% by weight or more, the ceramic fiber becomes rigid, so that it is easily broken.
In addition, the handleability is extremely poor, and the inorganic fiber layer is crushed by the vibration of the engine, which may cause a reduction in the filter holding power and a reduction in the sealing performance.

It is preferable that an organic and / or inorganic binder is added to the inorganic fiber layer 17a to maintain its shape. If the addition amount of the organic and inorganic binder is small, the shape becomes poor. It is not contained, and if too large, the elasticity is impaired. Therefore, it is preferable to contain 5% by weight to 30% by weight.

The hollow frame 15 is preferably made of stainless steel such as SUS304 or SUS316L from the viewpoint of heat resistance and durability. The side 15a of the frame 15 is bent into an L shape along the side of the lower inorganic mat 17, and the tip 15b is further bent upward,
It constitutes a guide member when mounted on the filter 2. In this way, a part of the frame body is bent to serve as a guard portion that covers the surface of the inorganic mat in the clean gas side space of the ceramics filter, thereby protecting the surface of the inorganic mat from strong backwash gas flow. Thus, the durability of the sealing material can be further increased.

The inorganic mats 16 and 17 and the frame 15 are waterproofed. The waterproof treatment is performed by dipping in a water repellent or spraying a water repellent. As the water repellent, a silicone-based water repellent is preferable. The waterproof treatment is applied to the inorganic mats 16 and 17 and the metal plate 15 separately or after assembly. The waterproof treatment using a water repellent can be performed regardless of the shape of the mat, and the productivity is high.

In the seal member of FIG. 5, similarly to the seal member of FIG. 3, the inorganic mats 16 and 17 are fixed to the upper and lower surfaces of the frame portion of the hollow frame 15. Inorganic mat 17
The outer periphery of the inorganic fiber layer 17a is covered with a metal foil 18. This is to prevent moisture and the like in the gas from entering the inorganic fiber layer 17a. Note that the coating with the metal foil is not general, but rather the inorganic fiber layer 17.
It may be applied only to the side surface (the right side surface 19 in FIG. 5) in contact with the gas a or only to the top surface, the right side surface and the bottom surface of the inorganic fiber layer 17a.

As the foil 18, for example, aluminum can be used. Further, a thin metal plate may be used instead of the metal foil. The thickness of the metal foil or thin plate is preferably 0.02 mm to 0.1 mm because it is easily broken when it is thin, and it is difficult to cover it when it is thick. The number of coatings or the number of coatings is preferably 1 to 1 because if the number of coatings is large, water that has entered the gaps between the foils and thin plates is difficult to drain. Waterproof treatment using metal foil or thin plate is heat resistant,
It has corrosion resistance and excellent durability. In FIG. 5, the inorganic mats 16 and 17 may or may not be subjected to the water-repellent treatment. The coating with a metal foil or thin plate is performed only on the inorganic mat layer 17b, or on the inorganic fiber layer 17a and the inorganic mat layer 1b.
It may be applied to the entire inorganic mat 17 including 7b.

In the seal material shown in FIG. 5, the inside of the frame 15 is bent inward like 15c, and the inorganic fiber
The layer 17a is designed to protect the side surface in contact with the gas. The length of the bent portion may cover the entire side surface 19 of the inorganic fiber layer 17a or the entire side surface of the inorganic mat 17.

In the seal material shown in FIGS. 3 and 5, for example, a carbon-based paste may be used instead of the upper inorganic mat 16, and the inorganic mat 16 may be omitted.

[0033]

【Example】

Example 1 A hollow frame made of stainless steel having a thickness of 0.6 mm (length 11.6 cm, width 21.7c)
m) on both the upper and lower sides of the frame (width 1.4 cm).
A 5 mm inorganic mat ("Pira-mat" manufactured by Nippon Pillar Co., Ltd., containing 920 g / m ² in weight and about 20% by weight of permiculite) manufactured by Nippon Pilar Co., Ltd.
SW820), a seal material to which a heat-treated and water-repellent treated product was fixed was immersed in water for 1 day, and dried at 120 ° C. for 4 hours. It is attached to the particulate trap apparatus of the present invention shown in FIG.
kg / cm ² ) for 300 hours, during which regeneration is 450
Performed 0 times. As a result, no dust leakage was observed.

The test was conducted under the following conditions by connecting the particulate trap device shown in FIG. 1 to a diesel engine. Diesel engine displacement 6560cc Diesel engine output 120PS / 2150rpm Diesel engine exhaust gas temperature 520-560 ° C Filter (cross flow type) Dimensions 20cm × 10cm × 14cm Filter effective filtration area 2.1m ² (on one side) Compressed air tank capacity 35 liters configuration of the sealing material of Fig. 3 that the soot amount Bosch concentration second sealing material metal plate backwash interval 4 minutes engine outlet of atm compressed air tank pressure 7 each filter was SUS304 plate, pressure of about 5 kg / cm ² preheated to about tightening Only heat of diesel engine exhaust gas at 500 ℃

<Comparative Example 1> A test was conducted under the same conditions as in Example 1 except that the inorganic mat was not subjected to a water-repellent treatment. The concentration of particulates in the clean gas was measured 60 hours after the start of the test. However, the Bosch concentration became 1 (there was a clear leak). When the seal material was observed after the end of the test, it was found that particulate matter had adhered to the surface of the inorganic mat exposed on the clean gas side of the seal material.

<Example 2> In the inorganic mat on the side of the frame body that comes into contact with the filter, a ceramic fiber layer having a thickness of 7.5 mm (weight of about 150
0 g / m ² , 70% by weight of Al ₂ O ₃ alumina silica-based ceramic fiber fiber layer) was immersed in a silicon water repellent (TSW820 manufactured by Toshiba Silicone Co., Ltd.) to perform a water repellent treatment. .04 mm aluminum foil and 2.5 m thick on the side in contact with the filter
m of inorganic mat layer (weight: 920 g / m ² , “Pira-Mat” manufactured by Nippon Pilar Co., Ltd. containing about 20% by weight of permiculite) and silicon water repellent (TSM manufactured by Toshiba Silicone)
W820), a laminated mat formed by laminating those subjected to a water-repellent treatment was used. Except for this, the test was conducted under the same conditions as in Example 1, and no dust leakage was observed.

Example 3 Example 2 was repeated except that the ceramic fiber layer was not treated with a silicon water repellent.
When the test was conducted under the same conditions as in the above, no dust leakage was observed.

[0039]

According to the particulate trap apparatus and the seal material of the present invention, the inorganic mat constituting the seal material and the entire seal material are waterproofed, so that the inorganic mat absorbs moisture. However, even if there is water condensed in the exhaust gas or in the apparatus or water containing a water-soluble salt, the restoring performance of the inorganic mat does not deteriorate and dust does not leak.

[Brief description of the drawings]

FIG. 1 is a sectional view of a particulate trap device of the present invention.

FIG. 2 is a plan view of a seal material.

FIG. 3 is a cross-sectional view of the seal material taken along line AA of FIG. 2;

FIG. 4 is a partial cross-sectional view of a seal material disposed between a metal case and a filter.

FIG. 5 is a partial cross-sectional view of another seal material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal case 2 Filter 3 Dust-containing gas inlet 4 Dust-containing gas side space 5 Clean gas side space 6 Clean gas outlet 7 Backwash valve 8 Backwash gas inlet 9 Particulate receiving part 10 Sea heater REFERENCE SIGNS LIST 11 Ash outlet 12 Air inlet 13 Seal material 14 Seal material 15 Frame 15a Side 15b Tip 16 Inorganic mat 17 Inorganic mat 17a Inorganic fiber layer 17b Inorganic mat layer 18 Metal foil 19 Inorganic fiber Layer sides

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Shigeru Osaka 1150 Hazawa-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Inside the Central Research Laboratory, Asahi Glass Co., Ltd. Asahi Glass Co., Ltd. Sagami Works (72) Inventor Kazuhiko Takesa 426-1 Ozawa Uehara, Kakuda, Aikawa-cho, Aiko-gun, Kanagawa Prefecture Asahi Glass Co., Ltd. Sagami Works

Claims (10)

[Claims] A filter provided with a dust-containing gas flow path and a clean gas flow path divided by a filtration wall is provided with a metal case through a seal material.
A particulate trap device wherein the filter is regenerated by a backflow means for generating a backflow gas, which is held in the cleaning gas flow path from the clean gas flow path side to the dust-containing gas flow path through the filtration wall, wherein the seal is provided. A particulate material which is waterproof and is provided with an inorganic mat containing a component which expands when heated and which is heated, at least on a side of the upper and lower surfaces of the frame portion of the hollow frame member in contact with the filter. Trap device. 2. An inorganic mat comprising: an inorganic fiber layer;
2. The particulate trap device according to claim 1, comprising a laminated mat with an inorganic mat layer containing a component which expands when heated. 3. The particulate trap device according to claim 1, wherein the waterproof treatment is performed on at least the inorganic fiber layer. 4. The particulate trap apparatus according to claim 1, wherein the waterproof treatment is performed by a water repellent treatment with a water repellent. 5. The particulate trap device according to claim 1, wherein the waterproof treatment is performed by coating the inorganic mat entirely or partially with a metal foil or a thin plate. 6. The method according to claim 1, wherein the water-repellent treatment is a water-repellent treatment with a water-repellent agent.
The particulate trap device according to any one of claims 1 to 3, wherein the inorganic mat is entirely or partially covered with a metal foil or a thin plate. 7. A waterproof or non-waterproof inorganic mat containing a component which expands upon heating is disposed on the side of the frame portion of the frame body which does not come into contact with the filter. A particulate trap device according to any one of the preceding claims. 8. The particulate as claimed in claim 1, wherein the frame is waterproofed with a water repellent.
Trap device. 9. An inorganic fiber, wherein at least the upper and lower surfaces of the frame portion of the hollow frame having a shape corresponding to the peripheral portion of the filter have been subjected to a waterproof treatment at least on the side in contact with the filter.
A seal material comprising an inorganic mat formed of a laminated mat of a layer and an inorganic mat layer containing a component which expands when heated. 10. The method according to claim 9, wherein the inorganic fiber layer is waterproofed by a water repellent treatment with a water repellent and / or by coating the inorganic fiber layer entirely or partially with a metal foil or thin plate. The seal material as described.