JPS58143817A - Filter apparatus for removing combustible fine particle - Google Patents

Abstract

PURPOSE:To remove filtered combustible particles efficiently by combustion, by a method wherein the wall structure of a filter is formed from a porous conductive ceramic and a voltage applying means is provided to the outer peripheral wall of the filter to heat the wall structure by passing a current therethrough. CONSTITUTION:In a filter apparatus for removing combustible fine particles in an exhaust gas, a wall structure is formed from porous conductive ceramic based on silicon carbide. A gas flowed in from the end surface 21 of a filter enters an inlet passage group 1 from each inflow port 3 and passed through a porous filter wall 7 to discharge only the gas through an outlet passage group 4. In this case, fine particles in the gas are collected by the filter wall 7 and only the gas is flowed out from each outflow port 4. At this time, when voltage is applied between both electrodes of the filter apparatus to pass a current, the filter wall generates heat to raise the temp. of combustible fine particles such as carbon particles and to remove the same by combustion.

Description

[Detailed description of the invention]

The present invention relates to a filter device for removing combustible 14+ particles contained in gas, particularly combustible particles such as carbon contained in exhaust gas from automobiles. By letting
The present invention relates to a filter device that efficiently burns and removes filtered combustible particulates while maintaining high filtration. Conventionally, it has been proposed to use a filter in the exhaust system of an automobile engine, especially in order to remove carbon particles contained in the exhaust gas of the engine, as a pollution control measure. However, when used for a long period of time, carbon builds up and causes clogging, resulting in pressure loss. In order to overcome this drawback, we combined a Nichrome X-ray heater or a photothermal metal layer in the particulate trapping part of the filter.
At the same time, heat the fili by applying electricity, or apply fuel to the fili capture site.
Heating can be done by heating with the combustion heat of J%-C fuel, by installing a high-voltage electrode and heating by spark discharge, or by heating with carbon fiber eaves.

[ and then heat the carbon fibers by passing an electric current η to sinter the carbon fine particles 711 and [
A method was taken to prevent clogging. However, when using a 1] membrane wire, the heat generating area is small and the energy efficiency is poor.Furthermore, it is time-consuming to attach the heat generating metal layer to the filter (', l).
If a filter is used, it must be installed in a narrow and small area to prevent filtration. If that doesn't work, you may have to burn off the carbon particles that fill the tank after stopping the engine.Also, the fuel 11FI rule and high ff discharge method are exceptional. It requires out-of-sight equipment, consumes a lot of energy, causes problems such as fire caused by fuel, damage to filters due to discharge, and if carbon fibers are used, the fibers themselves may burn due to combustion. On the other hand, a ceramic honeycomb structure filter is known for similar purposes, and this filter has finer mesh than the general R-3 filter. It is suitable for removing carphones from automobile exhaust gas because it has low pressure loss and is non-abacting. However, if clogging occurs,
Since the filtration surface covers a wide range, the filter can be used easily.
In view of the above-mentioned drawbacks of the previous technology, the present inventors have developed the following method:
As a result of intensive research, a ceramic honeycomb structure was developed with the aim of efficiently removing combustible particulates without worsening pressure loss or requiring a particularly complex setup. By using the filters as energized heating elements, the current equipment has to be drastically changed to 4T.
They discovered that combustible particles can be removed efficiently and completed the present invention. The gist of the present invention and the point of 1J is that it uses a wall structure that forms a plurality of passages extending from the population side to the exit side, and that the passages are closed with an exit side and an exit side. Entrance 1] Passage group entry 1] side is closed with entry 1] closing wall - 4
- Outlet [1] passageway group white, so that one inlet one passageway has at least one outlet [one passageway and a wall] ξ with a filtration wall for trapping flammable signs. In a J filter, at least the wall structure is porous and conductive and is formed by one stain, and a voltage applying means for heating the wall structure by electricity is provided on the outer peripheral wall of the filter. 'J Particulate Removal Filter Device. Next, explanation will be given with reference to the figures. FIG. 1 is a front view of a cylindrical filter device according to an embodiment of the present invention, and FIG. il shows a sectional view thereof, and FIG. 33 shows a partially broken schematic perspective view thereof. In FIG. 1, reference numeral 1 denotes an inlet passageway . Similarly, the outlet 1''4 of the outlet passage group 2 opens at the opposite end 22 of this end face 21, and the filter device
Together with 0, the whole forms a cylindrical body. Next, as explained in FIG. 2, the entrance passage JIY1 is
The end of the passageway opposite the inlet 3 into which the gas enters -5- is closed at a closure v5, the sides of which are covered by a porous electrically conductive ceramic filter wall 7, which, as a whole,
A hole with a rectangular cross section of 11゜ is formed without passing through the hole. Outlet [1] Passage group 2 is closed by a closing wall 6 at the end of the passage opposite to the outflow ITI /I through which the gas flows out, and the side surface of A is made of porous conductive material similar to the passageway 1. The filter wall 7 is made up of four sides of a ceramic filter wall 7, and as a whole forms a hole with a square cross section without any threads. and entry]-1 passage fiY 1 each passage and exit passage group 2
The passages are arranged adjacent to each other and share one or more filter walls 7, and if the passage 1.2 has a square cross section, up to four sides of one passage are the inlet passage and the outlet passage. The overall arrangement is as shown in Figure 1, with a square inlet 13 or 4 at each end forming a checkerboard pattern with a closing wall 5 or 6. On the external surface of the cylindrical side wall 20, metallic electrodes 8.9 for voltage application are formed in a strip shape from the end portions 21 to 22 at regular intervals. It is best to set the width of each electrode around 60''' when viewed from the center line of the cylinder, and set VL to 50' to 80' from the point of view of uniform heat generation in the honeycomb cross section. . The gas filtration effect of this embodiment will now be explained.The gas first flows in from the direction of the end face 21, and then enters the inlet passage flY1 from each inlet port 3 that is connected to the end face 21. Porous filter wall 7 as shown by the dotted arrow in Figure 2
It passes through the hole [-) and leaks into the adjacent outlet passage group 2. At this time, fine particles in the gas are captured by the filter wall 7,
Only gas flows out from each outlet 4 through the I passage 11Y2. At this time, if a voltage is applied between both electrodes of the filter device and electricity is applied, the filtration wall 7 of the filter will generate heat, and the temperature will exceed the combustion temperature of carbon, etc.: The filtration wall The i11 bamboo mold particles such as carbon trapped in the carbon burn and disappear. Here, the filter wall 7.20 and the closure %t 56 are made of porous conductive relamic, and the inflow [)3-7
= It acts to filter the gas that has entered the inlet 1-1 passage 1 and guide it to the outlet 4 from the outlet 1] passage 27p +, and the pore diameter is usually 2μ ~
30 // later, it is suitable for capturing combustible 1'l fine particles such as carbon. 1. :However, it is not necessary for the filter wall 20 or the closing wall 5.6 to be porous in Hi, but it is better to have the same material so that it is less likely to be damaged by W such as ) 111 heat 14 etc. Here, the ceramic DFi tl used for the filtration wall 7 and the closing wall 5.6 is mainly composed of carbonized carbonized fibers (chemical formula SiC) or -f1-formed liveden (chemical formula MO8iz). Zuru i-) is used, especially molybdenum silicide, which has 11 components, and changes in electrical resistance against thermal ulcers exhibit 11 characteristics in the entire temperature range in which it is used, making it easy to adjust the temperature. . In order to manufacture the honeycomb structure of the -C filtration wall in the above embodiment, Example A is carried out as follows. In addition to ingredients such as carbide or molybdenum, fine powders such as alumina, silica, etc., sodium alginate, ammonium aluminate, polyvinyl fluoride, etc. An organic binder such as, water, and a solvent such as ethyl alcohol E3- are added and kneaded to make a mixture, and the cross-sectional shape of the through hole is polygonal such as triangular, square, hexagonal, circular, oval, etc. By extruding from a die consisting of many slits so as to form a predetermined shape, a long piece of integrated structure is obtained, and the raw filter wall is cut into the required shape. It is possible to obtain a honeycomb structure. Next, in order to manufacture a filter device from the honeycomb structure, for example, gas inlets of all inlet passages BY1 are placed at the inlet]=1 passage 1 and outlet [1 passage 2 inlet 1] side ends of the structure. 3
A raw ceramic sheet punched out only at the location is pasted using a paste-like composition of raw ceramic as a binding agent to form the closing wall 6, and in the same manner, a gold mine [ Paste a raw ceramic sheet that has been punched out only at the gas outlet 4 of the first passage group 2. It is possible to select various shapes such as a square prism and a cylindrical body, and it is also possible to select various shapes for the passage such as a square prism, hexagonal 6, triangular odd 1 etc. -1] Metal powder paste 1" such as platinum is applied to the outer surface of the cylindrical side wall 20 of the (fired cylindrical) router.
- Or nickel, = 1 balt, etc. and silicon powder paste 1 ~ mixture is burnt in strips at intervals, and the filter device is laminated with 1 metal electrode 8.9.
You can do it. Further, in order to provide airtightness to the side wall 20 of the filter device row, the glass-containing ceramic layer can be partially or entirely fired, so that the high temperature 111 gas leaked from the side wall 20 is absorbed by other gases. It is possible to prevent any adverse effects on the parts. The shape of the filter device is not cylindrical or 4-J, but may be prismatic, for example. FIG. 5 shows a square prism-shaped filter device. Metallic N poles 23.2 /I 4;t are provided on two opposing sides of the four sides of the filter device. FIG. 4 shows an example of application of the present invention as a filter device for filtering automobile exhaust gas. Here, 16 +; is the Noirta mounting for the combustible particulate 1 part - 10 - membrane of the present invention, and
1 /Ia, 1 /Il+, J, outer cylinder 18
9, the outer cylinder 1B is fixed to, on its inflow side,
The flange 16a of the joint pipe 16 is connected to the flange 18a, and 2r,
-1- Connected to the seat manifold -C. 115 on the outflow side, which is the 1st side, is the collar part 1811
It is connected to the flange 171) of the joint tube 17, and is connected to the trachea.The conductor 12a is electrically connected to one of the electrodes 8 of the filter wave shield 10 by the other one step. , outer cylinder 1
The insulator 13ξ1 penetrated through the insulator 111 is led to the outside while maintaining an insulated state with the insulator 111, and is connected to the negative side of the power source E and grounded. The other? IIi pole 9 conductor 121) is wax (=J (J
(electrically connected to the cylinder 18 by other means) 1
TiQ insulator 13 maintains the insulated state with the Φ body by tl, and the I piece is passed to the outside and connected to the power supply side 11
These power supplies R: , ;
xi line] 2a, 121), the switch 15 and the filter device 10 together form a heating circuit. -11- 10-port configuration - (The exhaust gas containing carbon fine particles from the II engine passes through the 1-A exhaust manifold and connecting pipe 16) towards the 1st flow vent. Filter device for removing particulates a?
Flow into Jru1, then 1no1 as shown by the dotted line in Figure 1.
The gas passes through the filter wall 7 and exits to the output 1" passage 2 (, fi
! From II 4, the filter is sent out to the outside, downstream 0) 1 nol, in the direction of the trachea. By passing through the filter wall 7, the carbon particulates in the II gas are captured by the filter wall 7, and the ljl dregs containing almost no carbon particulates flows out from the inside. At this point, turn on the IF5 and apply current between both electrodes 8 and 9 to generate heat in the router device 10 and heat the carbon particles to the ignition humidity, causing the carbon to burn. Carbon disappears (1st place 11 (product J, runo r)
It is possible to prevent the loss of strength due to clogging of letters. In this heating circuit, the conducting wires 128 and 121) are exposed to the space where the carbon particulates are flowing, and the 7J-bon particulates are not exposed to the surface.
Shield 1 (n lt!l is cool to write, so show 1
This is advantageous because it eliminates the fear of 1°.Also, the fact that catalyst metals such as platinum are supported in a dispersed manner within the porous wall structure of this filter makes it possible to reduce the sintered Ml of carbon at low humidity. Since you can do it, you will be right-handed. This can be obtained, for example, by immersing the porous wall structure in a catalytic metal acid or liquid, followed by heat treatment at relatively high humidity. As described above, according to the filter for removing combustible 111 particulates of the present invention, a plurality of passages are formed extending from the inlet side to the outlet side. A group of inlet passageways closed with a closing wall has an inlet side and an outlet closed with a closing wall. The filter has a filtration wall for trapping combustible particulates by forming at least a wall structure of porous conductive ceramic, and an electric current for heating the wall structure. ] - By arranging the application means on the outer peripheral wall of the filter, the filter structure for carbon particulate filtration and heating can be simplified without changing the shape of the conventional honeycomb structure type filter. This makes manufacturing easier. In addition, since the entire filter, especially the filter wall itself, generates heat during use, all of the captured carbon is efficiently heated and incinerated, and moisture is removed quickly, resulting in good energy efficiency. Moreover, the pressure loss is small and the carbon particulate capture property is good.
It maintains the inherent advantages of honeycomb structure filters. Incidentally, since the exhaust gas is also heated, the combustible particulates captured by the filter are efficiently burned and extinguished. Next, a detailed manufacturing example will be given and explained. Example 1 Silicon carbide powder, boron carbide (chemical formula BaC) as a burning aid, phenol resin, and Graphi 1 powder (average particle size 25 u) as a pore size control agent were mixed into 5i (E:
100, [3aC: 0.25, phenol-14-ol resin: 5, graphite powder: 15 weight 171 people' 1 mixture was mixed into 100, polyvinyl] norkol:; 3, Water: 25 parts blended and kneaded b
Extrude it through a mold, mold it into a long piece that fits the passage in the open state, cut it to the required size, and make one piece of the cow's wall (ql).Next. A cow sheet with the same composition as Juki, with the inlet [1 or outlet] removed in advance, was placed on both cut surfaces of the wall fS structure in the cut section 1, with the proportion of solvent among the above components. This was baked at 1950°C for 3 hours under a nitrogen atmosphere, and then heated at 1000°C with an extra flammable carton. 11
A filter is made by burning off the ζn component. Next, a mixture of 50% by weight of element 11 and 50% by weight of Niraglu and Kobal 1~ was heated to 1500°C with non-oxidized 1'l.
Sintered for 30 minutes in a J atmosphere to form an alloy, then crushed into pieces! : After applying a powder paste to the surface of a portion of both sheets 1 of the above-mentioned fired filter, drying it,
500'C non-oxidation +! 10 minutes in an atmosphere of 15 minutes
A filter device for removing 1 minute amount was obtained. Table 1 Diameter: 100 mm Length: 100 mm Filtration wall thickness: 0.5 mm Glue in passage - Square filtration area with sides of 3.0 mm
Approximately F'3200 mm2/in3 average porosity
5% Inner pore diameter 20μ Powder amount
50 Example 2 72 parts of molybdenum chloride powder, 8 parts of alumina, and 20 parts of graph J/I 1 to 20 parts of powder were treated with organic pine nuts, polyvinyl alcohol a Ri fi part and 20 parts of water. Half of the mixture was mixed and kneaded, and the same shape as in Example 1 was formed into strips 11C, and then fired, and further, the excess carbon component of combustion 11 was burned off at 1000 ° 0 in the atmosphere, and - I made a filter. Platinum-16 was applied to the surface of both seams of the obtained filter.
- Apply powder base 1~ (Ishi, popular, 1200
Baked at ℃, the cylindrical body rIl (fine traces of combustion), and the river filter device 1r: Also, the properties of the 9°C were determined except that the interelectrode resistance 1i1 of the explosion was 0.30 (and Same as Table 1, the temperature between the two electrodes of the filter S4i'fJ that was removed in Example 1 of the 1-starvation test [when a voltage of 26 V was applied in this heat, from room temperature to a temperature exceeding 6001] , in 108 seconds). On the other hand, when a voltage of 26V was applied in the atmosphere between both electrodes of the filter device obtained in Example 2,
A temperature exceeding (') °C was reached in 103 seconds. Also, since the molybdenum disilicide filter is a genuine product, temperature control is easy.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of a filter device for removing combustible fl particulates according to the present invention, and FIG. 2 is a sectional view taken along line II-IT thereof.
Figure 3 is a partially cutaway schematic perspective view of the same, and Figure 4 is a schematic perspective view of the car.
11 Schematic cross-sectional view of filter device applying dregs filtration -17- Fig. 5 is a schematic perspective view of another actual/dli example. 1...Input 1] Passage 11Y 2...Output 1] Passage IIY 7...Filtration b? 8.9.23.2'l...Metal Y'1↑11Public Agent Patent Attorney Tsutomu Seitatsu-18- Procedural Amendment Book Type) June 2, 1980 2 Name of Invention Flammable Particulates Removal filter device 3, relationship with the person making the correction Patent applicant address 14-18 Takatsuji-cho, Mizuho-ku, Nagoya Name <454) NGK Spark Plug Co., Ltd. Representative Osamu Ogawa 4. Agent 4.60 Address: 2-9-27-5 Nishiki, Naka-ku, Nagoya Date of amendment order: May 25, 1980 (Date of dispatch) Figure 2

Claims (1)

[Scope of Claims] A wall structure forming a plurality of passages extending from the population side to the exit [1] side, the passages having an inlet [1 passage 1 '
In a filter having a filtration wall that shares a wall with one passage and captures combustible particles, at least the wall structure is formed of porous conductive ceramic, and the @1F4 structure is heated by electricity. A filter device for removing combustible particulates comprising a voltage applying means provided on the outer peripheral wall of the filter. 2. Claim 1, wherein the porous conductive ceramic is mainly composed of silicon carbide. Combustible particulate removal+11 filter device.3 Porous conductive↑1 Ceramic is a ceramic whose main component is molybdenum diT:l chloride.Claim No. 1-1
- A filter device for removing combustible particulates as described in Section 1.