JPH10328516A - Laminated spiral honeycomb structural body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a unique shaped laminated spiral honeycomb structural body capable of being used for a catalyst carrier, dust collection or the removal of smoke with validity kept through a long period. SOLUTION: The laminated spiral honeycomb structural body is formed by providing an opening part having a pattern having many regular polygonal or circular shape holes regularly arranged in hexagonal or square symmetry on a rigid or porous thin plate material and laminating to integrate many numbers of the thin plate materials so that the center of each hole shifts respectively along the circumference of a fixed curvature by successively sliding little by little without rotating the opening part pattern. As a result, the laminated spiral honeycomb structural body formed so that the whole honeycomb through holes are spirally curved while respectively keeping a fixed interval and having a novel unique function is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is not only a ceramic honeycomb for a high-performance catalyst carrier, but also a laminate having a unique shape which maintains the function of separating and removing particulate matter floating in a gas stream such as exhaust gas for a long time. It relates to a spiral honeycomb structure.

[0002]

2. Description of the Related Art Conventionally, a honeycomb body used as a catalyst carrier for an automobile is manufactured by extruding a mixture of alumina, cordierite, silicon carbide, or metal powder and sintering the same. The through holes were exclusively linear. Therefore, the through hole needs to be relatively small and long as a catalyst carrier in order to maintain sufficient contact between the catalyst and the gas, and when used in a combustion furnace or the like, the catalyst carried by dusts and the like contained in exhaust gas. However, there was a disadvantage that it deteriorated in a short time.

Recently, black smoke discharged from a chimney of a combustion furnace or the like has become a problem as an environmental pollution. However, it is generally very difficult to remove ultra-fine particulate matter, and it cannot be collected by a cyclone. Bag filters and the like clogged in a short time and lost their effectiveness, and electric dust collectors became large-scale and costly, and each had fatal drawbacks. In addition, despite the urgent demand for the problem of black smoke removal from diesel engines, there is no appropriate solution.Therefore, the through holes of the honeycomb body are alternately closed at the entrance and exit, and the porous body is made porous. A method of using the inner wall of the through hole as a filtration membrane has been attempted. Naturally, also in this structure, the entire inner wall is clogged in a short time as in the case of the bag filter, and it is necessary to constantly oxidize and remove the soot deposited and deposited.

[0004]

The present invention fundamentally solves these problems. As a catalyst carrier, it can maintain catalytic activity for a long period of time with respect to exhaust gas containing fine particles, and furthermore, it can suppress the emission of smoke and the like in the exhaust gas. An object of the present invention is to provide a specially shaped laminated spiral honeycomb structure having a function of removing particulate matter very effectively and for a relatively long period of time.

[0005]

For this purpose, the present invention provides a dense or porous thin plate material, in which a large number of regular polygonal or circular holes are regularly arranged in a hexagonal or tetragonal symmetry, and an opening of a figure is provided. A large number of sheets are laminated and integrated one after the other with a slight shift without rotating the opening figure so that the center of each hole moves along a constant curvature circumference, and the honeycomb through holes are all spaced apart from each other by a certain distance. A spiral helical honeycomb structure having a special shape characterized by being helically curved while maintaining the above is devised.

[0006] When a part of the outer frame of the thin plate is made to coincide with each other at the time of lamination, all the honeycomb through holes are spirally curved while maintaining a certain interval from each other. A laminated spiral honeycomb structure composed of a large number of thin plates in which the geometrical relationship between the outer frame and the opening portion is changed little by little so as to be linear and vertical is invented.

[0007]

As the laminated thin sheet material of the laminated spiral honeycomb structure of the present invention, basically any material can be used in accordance with the purpose and economy, but naturally a metal or ceramic material is required for a high temperature purpose. A somewhat flexible or machinable thin plate, such as a thin plate, metal mesh, ceramic fiber paper, or a sheet-like molded product of ceramic powder, is selected. The formation of a large number of regular polygonal or circular holes regularly arranged in hexagonal or square symmetry for these sheet materials is achieved very simply by a continuous stamping process. The flexible sheet of the ceramic powder is formed into a ceramic by firing after punching.

FIG. 1 shows an example of four different thin plates in which an opening figure 2 in which regular hexagonal holes are arranged symmetrically in a hexagonal outer frame 1 is formed. These are 4 of the set of 32 laminated sheets, 3 is the 1st, counting from the bottom, 4 is the 9th, 5 is the 17th, and 6 is the 25th. It is. The relative positions of the opening figure 2 with respect to the outer frame 1 are different for each thin plate. When 32 of these thin plates are stacked so that the outer frame 1 matches, the opening figure 2 is sequentially rotated from the bottom without rotating. Slightly displaced, the center 8 of a certain regular hexagonal hole 7 is arranged in such a manner that each center 8 turns clockwise along a turning circle 9 having a constant curvature,
A spiral honeycomb through-hole is formed by connecting the holes. Such relative displacement of the opening figure 2 can be easily achieved by slightly shifting the relative positions of the thin plate and the punching press die by computer control.

FIG. 2 is a perspective view of an arbitrary one of the honeycomb through-holes formed when the above-mentioned 32 thin plates are stacked, as viewed from above. All the regular hexagonal holes of the opening figure 2 draw the same perspective view, and since all the regular hexagonal holes do not touch each other, all the individual through-holes resulting from the stacked connection of the regular hexagonal holes are not included. Each is adjacent via a partition. FIG. 3 shows the shape of a spiral honeycomb through-hole formed by a large number of regular hexagonal holes when they are actually laminated, and FIG. 4 depicts the center 8 of an arbitrary regular hexagonal hole 7 of the opening figure by lamination. The shapes of the trajectories are all shown obliquely and obliquely. 3 and 4 show the case where the center of the regular hexagonal hole makes one turn with 16 laminated thin plates.

[0010] A number of thin plates having such open-portion figures are stacked such that the center of each hole in the figure causes an integer number of turns, and fixedly integrated to form a unitary spiral honeycomb structure. . When actually used in an engine, a chimney, or the like, they are mounted or installed in necessary places according to the purpose and scale, either as a unit, or by joining several in series or in parallel.

[0011] In the laminated spiral honeycomb structure of the present invention, since a large number of through-holes are each spirally curved, if the through-hole inner wall does not have air permeability, it is installed in a passage for combustion exhaust gas or the like. When the exhaust gas passes through the spiral through-hole, it is forced to turn along the inner wall. Therefore, gas molecules and fine particles floating in the exhaust gas collide with the inner wall of the through-hole under the cyclone-like centrifugal force proportional to the square of the flow velocity and the reciprocal of the radius of curvature of the spiral, and oil smoke floating in the exhaust gas Are separated by a difference in specific gravity from the fluid and adhere to the inner wall.

FIG. 5 is a view for explaining this. One arbitrary regular hexagonal hole 7 has a center 8 and a center circle 11 which are adjacent to the regular hexagonal hole 10 (the adjacent hole on the left side of FIG. 7). Since the layers are spirally stacked along the circumferences 9 and 12, the gas passing therethrough receives a cyclone-like centrifugal force in the direction of the thick arrow. Since this turning radius of curvature is very small compared to cyclones, the centrifugal force becomes considerably large,
Fine particles in the gas, particularly smoke and fine dust particles in the exhaust gas, collide with and adhere to the wall of the spiral through hole in the direction of the thick arrow (the left direction in the figure). At the stage where the centers 8 and 11 of the respective regular hexagonal holes have advanced 90 degrees along the turning circles 9 and 12 (moved upward in the drawing), the direction of the bold arrow also changes the direction by 90 degrees as shown in the figure. That is, the direction of the centrifugal force is always directed to the outer peripheral side of the spiral rotation like the cyclone, so the wall surface on which fine dust and smoke collide and adhere is always the outer peripheral wall surface of the spiral in the spiral through hole, and the opposite wall surface Hardly adheres. The same applies to the other adjacent regular hexagonal holes 13 and 14 (the adjacent hole on the upper side of 7 in the figure), and similar adhesion occurs in all the through holes of the honeycomb.

In the case where the laminated thin plate portion of the laminated spiral honeycomb structure of the present invention is made of a porous material such as fiber paper, a more specific action is added to the above-described cyclonic action. . That is, the gas itself passing through the through-hole also receives a centrifugal force in the direction of the thick arrow, and the wall on the side that receives some compression in the through-hole (that is, the outer peripheral side of the swirl) has a slightly negative pressure (the swirl). On the inner circumference side of
In addition, all the through holes are adjacent to each other with the partition wall therebetween under substantially the same conditions, so that a positive and negative pressure difference is simultaneously generated on both sides of all the through hole partition walls. In the case of FIG. 5, between the adjacent regular hexagonal holes 7 and 10, the positive and negative pressures on both sides of the partition are reversed every 180 degrees of the spiral turn, and the permeation through this partition is performed. As a result, a part of the gas changes the place between the adjacent spiral through-holes, and reciprocates or enters the partition repeatedly, so that the partition also acts as a filter, and relatively light oil and smoke fine particles in the exhaust gas. Even when the specific gravity difference between the fluid and the fine particles floating in the fluid is small, the adhesion of the fine particles to the partition walls increases, and the separation of the fine particles in the gas becomes more effective. The ratio between the filter-like action and the cyclone-like action of the fine particle separation is determined by the porosity and pore size of the partition walls, and depends on the material of the laminated thin plate and the state of the inner wall surface of the through-hole.

The smaller the radius of curvature of the spiral through hole is, the larger the centrifugal force acts. Therefore, it is desirable to reduce the circle of the spiral as much as possible, and generally to a degree slightly larger than about half the diameter of the through hole. Furthermore, if a spiral spiral is used, in which the turning radius of the inlet is large and the turning radius of the outlet is gradually reduced, the effect of centrifugal force will gradually increase toward the outlet, and particles that are difficult to separate will adhere near the outlet. The effect of relatively uniform adhesion from the entrance to the exit of the inner wall of the through hole can be expected. Further, as described above, when several unitary spiral honeycomb structures are connected in series and used, more complicated control is possible, and the spiral honeycomb structure of the unit close to the entrance does not have an inner wall of the through hole. The layered spiral honeycomb structure, which is air-permeable and close to the outlet, has a small spiral turning radius, and is made of a porous, air-permeable partition wall, so that relatively coarse particles near the inlet and relatively near the outlet. In this case, extremely fine particles can be attached and removed.

Further, when a part of each outer frame of the thin plate is made to coincide with each other at the time of lamination, all the honeycomb through holes are spirally curved while keeping a certain interval from each other. A laminated spiral honeycomb composed of a large number of thin plates in which two kinds of geometrical relations of the outline frame with respect to the opening figure 2 are provided so as to be perpendicular to the straight line, and one of them is slightly changed for each thin plate In the structure, besides the particulate accumulation and collection action described in detail above,
A function of facilitating a cleaning operation for removing the accumulated fine particles from the honeycomb through-holes can be added.

FIG. 6 is an explanatory diagram of this. The outer frame 15 has a rectangular shape which is always in a fixed positional relationship with respect to the opening figure 2,
The outer frame 16 has a rectangular shape which is always in a fixed positional relationship with the spiral turning circumference 9, that is, the same relationship as the elliptical outer frame 1 in FIG. 1. Also, four laminated thin plates 17, 1
8, 19, and 20 are examples of a laminated spiral honeycomb structure in which the honeycomb through-holes become spiral or linear when the portion where the outer frame is matched is changed. Indicates the ninth sheet, 19 indicates the 17th sheet, and 20 indicates the 25th sheet.

First, 32 rectangular outer frames 15 each having the opening figure 2 formed at a fixed position are punched out in the same manner as 32 laminated thin plates, and then a portion corresponding to the outer frame 16 is formed diagonally. That is, this diagonal is formed by slightly shifting all the 32 sheets sequentially. In this case, when 32 sheets are laminated by matching the portions corresponding to the outer frame 15 of each laminated thin plate, each hole naturally comes to the same position, so that the honeycomb through-hole formed by the connection becomes linearly vertical, When the portions corresponding to the outer frame 16 are matched, the center 8 of the hole 7 is arranged in such a manner as to turn clockwise along the turning circle 9 having a constant curvature.
All the honeycomb through holes formed by connecting the holes are spirally curved while maintaining a certain interval from each other.
Such a relative displacement of the portion corresponding to the outer frame 16 with respect to the opening figure 2 can be easily achieved by slightly shifting the relative positions of the thin plate and the punching die under computer control.

The stacked spiral honeycomb structure of the present invention is extremely small in size as compared with other dust collecting devices, and can be manufactured at a relatively low cost by ordinary machining and ceramics techniques. Also, since the cross-section of the through-hole is the same as that of a normal honeycomb structure, even if fine-particle dust accumulates, the honeycomb through-hole does not become clogged for a relatively long time, and the resistance through which gas passes through the entire filter is reduced by ordinary filtration. It can be kept significantly smaller over the long term than the material.

Further, when the laminated spiral honeycomb structure of the present invention is used as a catalyst carrier, the exhaust gas often comes into contact with the catalyst by swirling collision, and a high catalyst efficiency can be obtained even with the honeycomb structure having a relatively large and short through hole. Can be demonstrated. If the exhaust gas contains particulate dust or oily smoke, they are preferentially attached and deposited on the outer peripheral side of the through-hole wall surface under the influence of the centrifugal force. The catalyst is less likely to be contaminated by dust in the exhaust gas, and can also exhibit a feature of preventing deterioration of the catalyst activity for a long period of time.

In the case of a large-sized combustion device that discharges a large amount of solid dust, it is desirable to install the ceramic honeycomb structure of the present invention after passing through a cyclone removing device. Although extremely fine particles that cannot be removed by a cyclone can be removed by the laminated spiral honeycomb structure of the present invention, the accumulated matter needs to be appropriately removed and cleaned as necessary. However, if the laminated plate as shown in FIG. 6 is used as it can be slid at any time without being completely fixed and integrated, at the time of dust collection, the outer frame 16 of each laminated thin plate is pushed from the diagonal direction so as to coincide with each other, and through the honeycomb. The holes are formed in a spiral shape to separate and accumulate dust particles. During cleaning when the accumulation of particles increases, the outer frame 15 is pushed from the diagonal direction so as to coincide with each other, and the honeycomb through holes are straightened to mechanically remove the sediment. Can be easier.

In the case of using only for smoke removal such as a diesel engine, it is possible to use the whole without heating by oxidizing, burning and burning combustible materials such as oil fumes without mechanical removal. It is possible. In dust incinerators, etc., the generation of smoke is temporary, and the laminated spiral honeycomb structure accumulates and deposits when smoke is generated, and when no smoke is generated, the attached oil smoke burns and burns, so cleaning and removing work is necessarily required And not.

Hereinafter, the production method of the present invention will be described with reference to a laboratory example, but the present invention is not limited thereto.

[0023]

EXAMPLE A metal nickel plate having a thickness of 0.3 mm and a ceramic fiber paper having a thickness of about 1 mm made of alumina fiber having a thickness of about 10 μm were used as laminated thin plates. Each of these 32 thin plates is sequentially cut into an elliptical outer frame and an opening figure substantially similar to FIG. 1, and these are sequentially and alternately laminated with the outer frames matched, and the outer frame is fixed and integrated. Thus, a laminated spiral honeycomb structure having a height of about 4 cm and substantially the same shape as that shown in FIG. 3 was formed. The opening portion of the laminated spiral honeycomb structure has a plurality of regular hexagonally symmetrically arranged through-holes, each of which is spirally curved while maintaining a certain interval from each other. The inner wall of the hole is layered and porous, and fine particles in the passing airflow can be captured by the inner wall of the through hole by a filter-like action in addition to a cyclone-like action.

[0023]

As described above, the laminated spiral honeycomb structure of the present invention has a special structure, which has not only an increase in efficiency and life as a catalyst carrier, but also a unique effect as a heat-resistant dust collector or a smoke removing device. Therefore, besides general use, especially if installed near the exhaust chamber of a dust incinerator, near the exhaust port of a diesel engine car, etc., incomplete combustion gas, sparks, smoke,
The emission of odor and the like can be significantly reduced, which is extremely useful for preventing environmental pollution due to combustion exhaust gas.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a change in the position of an opening figure with respect to an outer frame of a laminated thin plate.

FIG. 2 is a perspective view of any one of spiral honeycomb through-holes formed when 32 thin plate openings are stacked, as viewed from above.

FIG. 3 is a perspective view of a spiral honeycomb through-hole formed by laminating thin plate apertures as viewed obliquely.

FIG. 4 is a perspective view of a locus drawn by stacking a center 8 of an arbitrary regular hexagonal hole 7 as viewed obliquely.

FIG. 5 is an explanatory diagram of an action of a centrifugal force acting on an airflow passing through a through hole.

FIG. 6 is an explanatory diagram in the case where there are two types of geometrical relationships of the outline frame with respect to the opening figure 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Elliptical outer frame of thin plate 2 Opening figure 3 First of 32 laminated oval thin plates 4 9th of 32 laminated laminate 5 17th of 32 laminated laminate 6 25 of 32 laminated laminate Eye 7 A certain regular hexagonal hole 8 Center of hole 7 9 Circumference circumference of center 8 10 Regular hexagonal hole adjacent to left side of hole 7 11 Center of hole 12 12 Center 11
13 A regular hexagonal hole adjacent to the upper side of the hole 7 14 A regular hexagonal hole adjacent to the upper side of the hole 7 15 An outer frame having a fixed positional relationship with the opening figure 2 16 A fixed position with the rotating circumference 9 Outer frames in relation 17 First of 32 stacks 18 Ninth of 32 stacks 19 19th of 32 stacks 20 20th of 32 stacks

Claims (2)

[Claims] 1. A dense or porous thin plate material is provided with an opening having a pattern in which a large number of regular polygonal or circular holes are regularly arranged in a hexagonal or square symmetry.
The apertures are stacked and integrated by shifting them slightly in order without rotating so that the center of each hole moves along a constant curvature circumference, and all the honeycomb through-holes spiral while maintaining a certain interval from each other. A laminated spiral honeycomb structure characterized by being curved in a shape. 2. When a part of each outer frame of the thin plate is aligned during lamination, all the honeycomb through-holes are spirally curved while maintaining a certain interval from each other. Is perpendicular to the straight line,
A laminated spiral honeycomb structure composed of a large number of thin plates in which the geometric relationship between the outer frame and the opening is slightly changed.