JP2007198706A - Internal heating type heat exchange structure having intersecting passage directions - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact heat exchange structure with high heat efficiency, which is suitable for temporary heating of various fluids. <P>SOLUTION: In the heat exchange structure comprising a honeycomb structure integrally formed including a number of vertical passages 12 divided by partition walls 11 and extended in parallel in one direction and a heating means for heating a fluid, part of the vertical passages is closed at one vertical passage-directional end surface 13 of the honeycomb structure, and a turning-round part 15 connecting each closed vertical passage with each non-closed vertical passage 12 to reverse the flowing direction of the fluid is formed at the other end surface thereof, and a cross passage is formed in each closed vertical passage, the cross passage intersecting the vertical passages across the partition walls to connect the vertical passages to a hole formed in at least one side of the outer wall of the heat exchange structure. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat exchange structure that recovers internal heat generation, and more specifically, heat can be generated inside the heat exchange body, and fluid can be efficiently and temporarily heated using the heat generation. The present invention relates to a heat exchange structure that can be made.

  Temporarily heating a fluid is performed according to various demands in various industrial fields. For example, in the chemical industry field, heating a raw material to a temperature suitable for a target chemical reaction is performed in many chemical apparatuses. In the food industry field, heating of raw materials or products for the purpose of sterilization or the like is performed on various types of foods. Such heating is preferably performed by a compact device under high thermal efficiency.

Also, so-called malodorous gases or volatile organic solvents (VOCs) can generally be converted to odorless and harmless gases by combustion, but this combustion involves a large amount of relatively cool gas containing low concentrations of organic substances. Needs to be done.
Further, regarding exhaust gas from an internal combustion engine such as an automobile engine, in general, exhaust gas from a gasoline engine contains harmful substances such as carbon monoxide, hydrocarbons, and nitrogen oxides, and exhaust gas from a diesel engine further includes particulates. Is included. These harmful substances can be purified by the catalytic action of an oxidation catalyst, a three-way catalyst, a selective reduction catalyst, etc., but from the viewpoint of prevention of global warming, etc., reduction of carbon dioxide (CO ₂ ) emissions, that is, fuel consumption Improvement is also demanded. As the fuel efficiency is improved, the temperature of the engine exhaust gas inevitably decreases. Therefore, it is demanded that the purification by the catalytic action is performed even at a lower temperature.

On the other hand, by improving the air-fuel ratio control of the engine and the post-fuel injection technology, it becomes possible to include, for example, about several thousand ppm of CO in the exhaust gas in the presence of O ₂ without significantly reducing the fuel consumption. ing.
In the prior art, an apparatus or a device that advantageously performs exhaust gas purification by heat exchange using such heat generation components has been proposed (Patent Document 1, Patent Document 2, and Patent Document 3). In these apparatuses, a heat exchange structure based on an integral corrugated heat transfer surface is used as a compact structure that exhibits high heat exchange performance. In this case, in order to exhibit high heat exchange performance, it is necessary to keep the gap interval of the corrugated structure through which the fluid to be treated passes constant throughout the entire area. Alternatively, it is necessary to sandwich a gap between the gaps using a structure such as a plate-like wire mesh having a gap through which fluid can pass. It is technically difficult to make the corrugated heat transfer surface uneven with fine pitch, and is therefore not economical. Further, if the spacer is sandwiched between the gaps, the flow resistance is increased and the heat capacity of the device is increased, so that the performance as the heat exchange structure is greatly impaired.
In addition, it has been proposed that the honeycomb structure is provided with a heat exchange function to favorably react (Patent Document 4). However, in this proposal, the heat is exchanged between the fluids flowing through the two flow paths that are independent of each other across the heat transfer surface. Cannot be used.
JP 2000-189757 A JP-T-2003-524728 WO2004 / 099577A1 JP-A-8-283002

  The problem to be solved by the present invention is to further improve the heat exchange structure, and to provide a high heat efficiency and compact heat exchange structure suitable for temporarily heating various fluids.

The present invention is a heat exchange structure including a honeycomb structure integrally formed with a large number of longitudinal flow paths partitioned in parallel by walls and extending in one direction, and heat generating means for heating a fluid. There,
A part of the longitudinal flow path is plugged at one end face in the longitudinal flow path direction of the honeycomb structure, and the sealed vertical flow path is connected to the unsealed vertical flow path at the other end face. A wraparound that reverses the fluid flow direction is formed,
A transverse flow path that crosses the vertical flow path and connects the vertical flow path through the partition wall to each sealed vertical flow path up to a hole formed in at least one surface of the outer wall of the heat exchange structure. Is formed,
The fluid flowing in the longitudinal flow path upstream of the wraparound portion and the fluid flowing in the longitudinal flow path downstream of the wraparound portion form a countercurrent, and the heat generated by the heat generating means is The heat exchange structure is characterized in that it is transmitted from a fluid flowing in a flow path to a fluid flowing in the upstream vertical flow path via a partition wall.

  The heat exchange structure of the present invention uses a honeycomb structure to form a fluid flow path having intersecting flow path directions, thereby providing a structure having a compact and highly durable heat exchange function. be able to. That is, a heat exchange structure in which heat exchange occurs when a fluid flows through the structure is configured by appropriately providing the honeycomb structure with heat generating means, a wraparound portion, a plurality of transverse channels, and the like. Since this structure is based on a honeycomb structure, it can be configured compactly and with high strength, and since the honeycomb structure can be configured from a highly durable material that has been used, it has a highly durable heat exchange structure. can do.

  In the heat exchange structure of the present invention, the heat generated by the heat generating means is transmitted from the fluid flowing in the downstream longitudinal channel to the fluid flowing in the upstream longitudinal channel via the partition wall. That is, the heat generated by the heat generating means is returned from the downstream side to the upstream side, and this heat transfer further increases the temperature on the upstream side of the heat generating means, thereby further increasing the temperature immediately below the heat generating means.

  By returning the heat generated by the heat generating means to the upstream fluid in this way, the heat exchange structure of the present invention can function as a so-called self-heat exchange heater, and the temperature of the fluid can be efficiently increased. In the flow, can be significantly increased temporarily. For example, when the heat generation means gives the fluid an amount of heat corresponding to a temperature increase of 20 ° C. and the heat exchange rate through the partition wall is 80%, the maximum temperature of the fluid can be increased by 100 ° C. Here, this heat exchange rate of 80% is a level that can be sufficiently achieved in the heat exchange structure of the honeycomb structure of the present invention.

  The present invention provides a highly heat efficient and compact heat exchange structure suitable for temporarily heating a fluid. The heat exchange structure of the present invention can be applied to various uses. Specific examples include heating devices included in various chemical devices, and heating devices intended for sterilization in the food industry. , An odorous gas or volatile organic solvent (VOC) combustion purification device, an exhaust gas purification device of an internal combustion engine such as an automobile engine, and the like.

Several aspects can be implemented for the heat exchange structure of the present invention.
FIGS. 1 and 2 schematically show one preferred embodiment of the heat exchange structure of the present invention. The heat exchange structure is partially vertical on one end face in the longitudinal flow direction of the honeycomb structure. The flow path is sealed, and a wraparound portion that connects the vertical flow path sealed at the other end surface with the vertical flow path that is not sealed, thereby reversing the flow direction of the fluid is formed. FIG. 1 is a perspective view of the heat exchange structure, and FIG. 2 is a plan view thereof.

  In the heat exchange structure 10 of this embodiment, the plugging materials 13 are arranged in alternating rows on one end face of the honeycomb structure as an arrangement of the longitudinal flow paths 12 formed by the partition walls 11. Holes 14, 14 'are formed in two opposing outer walls where the sealed vertical flow path 12 is located, and penetrates the partition wall 11 between the series of sealed vertical flow paths 12. A transverse channel 16 reaching the holes 14, 14 'is formed.

  The fluid flows in from the longitudinal channel 12 that is not sealed in the heat exchange structure 10, passes through the upstream longitudinal channel 12, and reaches the wraparound part 15. The fluid changes the direction of flow at the wraparound portion 15, flows through the downstream longitudinal channel 12 in the opposite direction to the upstream longitudinal channel 12, and reaches the transverse channel 16. Dividing into two directions, it flows down through the transverse flow path 16 and out of the heat exchange structure 10 from the holes 14 and 14 ′ formed in the outer wall.

  Alternatively, the fluid flows in the opposite direction in the flow path, flows into the heat exchange structure 10 from two directions through the hole 14 formed in the outer wall, and enters the vertical flow path 12 collectively sealed by the cross flow paths 16. The heat exchange structure 10 flows in and flows through the upstream longitudinal channel 12, the wraparound portion 15, and the downstream longitudinal channel 12 that is not sealed from the longitudinal channel 12 that is not sealed. It can also flow out of the system.

FIG. 3 is a perspective view schematically showing another aspect of the heat exchanging structure of the present invention. As shown in the figure, the transverse channel 16 is passed through only one outer wall, and the other outer wall is passed through. Does not penetrate, but only penetrates to the bulkhead in front of it.
Also in this aspect, the fluid flows from the non-sealed longitudinal flow path 12 of the heat exchange structure 10 as in the previous aspect. Then, the fluid passes through the upstream longitudinal flow path 12, changes the flow direction at the wraparound portion, and flows through the downstream longitudinal flow path 12 in the opposite direction to the upstream longitudinal flow path 12, thereby crossing the flow path 16. However, it flows out of the system of the heat exchange structure 10 from the hole 14 formed in one outer wall.

  Alternatively, the fluid flows in the reverse direction through the flow path, flows into the heat exchange structure 10 from one direction through the hole 14 formed in the outer wall, and is longitudinally sealed by the cross flow paths 16 and sealed. The heat exchange structure passes through the upstream longitudinal channel 12, the wraparound part 15, and the downstream longitudinal channel 12 that is not sealed, in order, from the longitudinal channel 12 that is not sealed. It can also flow out of the 10 systems in one direction.

  Among these flows, the fluid flowing in the upstream longitudinal channel and the fluid flowing in the downstream longitudinal channel form a countercurrent, and from the fluid in the downstream longitudinal channel heated by the heating means, Heat transfer occurs in the fluid in the upstream vertical flow path through the partition wall 11 of the heat exchange structure 10.

In these embodiments, preferably, a transverse channel is formed in the vicinity of the plugging material 13 at the end of the longitudinal channel. Thereby, the longitudinal channel is used as an effective channel as a whole, and the area of the partition wall where heat transfer occurs can be maximized.
The transverse channel 16 can be formed by a gap between the sealing material 13 of the longitudinal channel 12 and the end of the partition wall 11. That is, by terminating the partition wall of the portion to be sealed shorter than the outer wall and communicating the space between the end of the partition wall and the sealing material, the space can be used as a transverse flow path. Alternatively, the transverse flow path can be formed by communicating holes with the partition walls of the honeycomb structure.

Various modes can be implemented for the sealed vertical flow path.
FIG. 4 is a plan view illustrating one embodiment of the sealed vertical flow path. In this aspect, the sealed longitudinal flow path forms a striped pattern on one end face of the longitudinal flow path of the honeycomb structure.

  FIG. 5 is a plan view showing another embodiment. In this embodiment, the sealed longitudinal flow path forms a lattice-like pattern on one end face of the longitudinal flow path of the honeycomb structure. Yes.

  FIG. 6 is a plan view showing still another embodiment. In this embodiment, the sealed longitudinal channel has a branched linear pattern on one end face of the longitudinal channel of the honeycomb structure. Is forming.

FIG. 7 is a plan view showing still another embodiment. In this embodiment, the sealed longitudinal channel forms a bent linear pattern on one end face of the longitudinal channel of the honeycomb structure. Forming.
These vertical channel patterns can be appropriately selected in consideration of desired flow uniformity, pressure loss, heat transfer area, and the like.

  The sealed vertical flow path is connected by a cross flow path and further connected to a hole formed in the outer wall. The outer wall surface on which the hole is formed may be one outer wall surface, that is, the inlet or the outlet to the heat exchange structure can be integrated into one outer wall surface, or the outer wall surface on which the hole is formed is 2 There may be more than one outer wall, i.e. the inlet or outlet to the heat exchange structure may be distributed to a plurality of outer walls. Similarly, the arrangement of the holes can be appropriately selected in consideration of desired flow uniformity, pressure loss, heat transfer area, and the like.

  In addition, the number of holes formed in the transverse flow channel and the outer wall surface connecting the series of vertical flow channels is not limited to one, and a plurality of holes can be formed, desired flow uniformity, pressure loss, etc. Can be selected as appropriate.

In the heat exchange structure of the present invention, the shape of the longitudinal flow path can be a shape that can be in the honeycomb structure, and specifically, the longitudinal flow path is triangular, quadrangular, hexagonal, and these A cross-sectional shape selected from a combination of:
Further, in the heat exchange structure of the present invention, it is not necessary to particularly limit the number and size of the longitudinal flow paths and the thickness of the partition walls, and within the possible range of the honeycomb structure, the type of fluid, flow rate, heat It can be appropriately determined in consideration of the size of the exchange structure, the required heat exchange rate, the allowable pressure loss, and the like. Similarly, the number and size of the transverse channels can be appropriately determined in consideration of the type and flow rate of the fluid, the size of the heat exchange structure, the required heat exchange rate, the allowable pressure loss, and the like.

  Further, in the heat exchange structure of the present invention, there is no need to specifically limit the material such as the partition walls and the outer wall, and the exposed atmosphere, temperature, type of fluid, etc. are considered within the possible range of the honeycomb structure. Can be determined appropriately. Ceramic materials such as cordierite and silicon carbide as general materials, and metal materials such as SUS304 and SUS310 are examples of suitable materials in the heat exchange structure of the present invention.

  When the heat exchange structure of the present invention is composed of the above ceramic material, it contains ceramic raw material powder, a binder, a dispersant, a sintering aid, etc., which are usually performed industrially, and is easy to mold. A method in which a ceramic material composition that is cured by firing is prepared, a honeycomb structure is formed by extrusion molding or the like, and then fired to produce a structure having a desired shape can be suitably employed.

  In such a method, after a honeycomb structure is integrally formed using a ceramic material composition, a plurality of transverse channels that connect the longitudinal channels are provided by perforating the partition walls of the longitudinal channels, or ends of the partition walls If a cross-flow channel is provided by filling the plug material composition with a gap between them and then the ceramic material compound is fired, the occurrence of damage and a decrease in strength are suppressed in forming the cross-flow channel. A heat exchange structure can be manufactured.

  As a preferable aspect, the outer wall of the heat exchange structure that extends beyond the longitudinal flow path is formed on the side wall of the wraparound portion. That is, the outer wall of the heat exchange structure is extended, the end of the outer wall is sealed to form a cavity at the end of the end of the longitudinal flow path, and the cavity is used as a wraparound part. Thereby, the heat exchange structure in which the wraparound portion is integrated in a compact manner can be configured.

  8 and 9 show a heat exchange structure which is still another preferred embodiment of the present invention, in which a part of the longitudinal flow path is plugged on one end face in the longitudinal flow path direction of the honeycomb structure, All the longitudinal channels are sealed at the other end face. The wraparound portion is formed by a transverse hole penetrating the partition wall at the end of the other sealed vertical flow channel so as to cross the extending direction of the transverse flow channel. FIG. 8 is a schematic perspective view of a heat exchange structure provided with such a transverse hole 17, and FIG. 9 is a plan view thereof. Also in this aspect, since the end portion of the longitudinal flow path is a wraparound portion, similarly, a heat exchange structure in which the wraparound portion is integrated in a compact manner can be configured.

  The heat exchange structure according to the present invention includes heat generating means for heating the fluid. The heating means can be selected from any that can heat the fluid in its flow.

In a preferred embodiment, the heat generating means is a catalyst that generates heat by a chemical reaction of a heat generating component contained in the fluid, and this catalyst is supported on a partition wall in the vicinity of the wraparound portion. Although not limited, the exothermic component is suitably a combination of a combustible component such as a hydrocarbon such as CO, H ₂ or CH ₄ and oxygen, and the catalyst is an oxidation such as Pt or Pd. A catalyst is suitably exemplified. In this aspect, for example, the heat generating means is configured by coating a partition material in the vicinity of the wraparound portion with a carrier material such as activated alumina by wash coating, and carrying Pt, Pd, etc. on the carrier material.

Alternatively, this catalyst can be arranged by carrying an oxidation catalyst such as Pt or Pd on a breathable material such as a pellet or a net and filling it in a flow path near the wraparound portion. .
By using such a catalyst, heat can be generated by an oxidation reaction or the like even for a fluid containing a combustible component of about 1% or less, such as about 1000 ppm of combustible component and several percent of oxygen. .

In another preferred embodiment, the heat generating means is an electric heater or a combustion burner disposed at or near the wraparound portion. That is, an electric heater or a combustion burner, which is a general heating device, can be used as the heating means in the present invention.
These heat generating means are preferably arranged at or near the wraparound portion. As a result, the heat generating means can be positioned at a substantially central portion of the flow path in the heat exchange structure, and the longitudinal flow path can be used to the fullest extent as a flow path where heat transfer occurs as a whole.

  The amount of heat supplied from the heat generating means is not limited, but as a guide, the average temperature of the fluid is 1 to 500 ° C, more preferably 5 to 100 ° C, and still more preferably 10 to 50 ° C. The amount of heat to be generated. The amount of generated heat is transferred from the fluid flowing in the downstream longitudinal flow path to the fluid flowing in the upstream longitudinal flow path through the partition wall, and this heat transfer further increases the temperature upstream of the heat generating means. As a result, the temperature immediately below the heating means is further increased.

  By such heat circulation, the heat exchange structure of the present invention can function as a so-called self-heat exchange heater, and can efficiently raise the temperature of the fluid temporarily in the flow efficiently. As described above, when the heat generation means gives the fluid an amount of heat corresponding to a temperature increase of 20 ° C. and the heat exchange rate through the partition wall is 80%, the maximum temperature of the fluid can be increased by 100 ° C. It can be used as a heating means with extremely excellent thermal efficiency.

  The fluid heated by the heat exchange structure of the present invention can be any fluid that needs to be temporarily exposed to high temperatures, and can be either a gas or a liquid, such as a suspension or emulsion. It can also be a fluid containing more than one phase, i.e. it can be any fluid fluid.

It is a perspective view which illustrates the composition of the heat exchange structure of the present invention. It is a top view of the heat exchange structure of FIG. It is a perspective view which illustrates the heat exchange structure of another mode of the present invention. It is a top view which shows one aspect | mode of the pattern of the vertical flow path sealed. It is a top view which shows one of the other aspects of the pattern of the longitudinal flow path sealed. It is a top view which shows one of the other aspects of the pattern of the longitudinal flow path sealed. It is a top view which shows one of the other aspects of the pattern of the longitudinal flow path sealed. It is a perspective view which illustrates the heat exchange structure of another mode of the present invention. It is a top view of the heat exchange structure of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Heat exchange structure 11 Partition 12 Longitudinal channel 13 Sealing material 14, 14 'Outer wall surface hole 15 Rounding part 16 Transverse channel 17 Transverse hole

Claims (20)

A heat exchange structure including a honeycomb structure integrally formed with a number of longitudinal flow paths that are partitioned by partition walls and extending in one direction in parallel, and a heating means for heating fluid,
A part of the longitudinal flow path is sealed at one end face in the longitudinal flow path direction of the honeycomb structure, and the sealed longitudinal flow path is connected to the unsealed longitudinal flow path at the other end face. A wraparound that reverses the fluid flow direction is formed,
A transverse flow path that crosses the vertical flow path and connects the vertical flow path through the partition wall to each sealed vertical flow path up to a hole formed in at least one surface of the outer wall of the heat exchange structure. Is formed,
The fluid flowing in the longitudinal flow path upstream of the wraparound portion and the fluid flowing in the longitudinal flow path downstream of the wraparound portion 5 form a countercurrent, and the heat generated by the heat generating means A heat exchange structure, wherein the heat exchange structure is transmitted from a fluid flowing in a longitudinal flow path to a fluid flowing in the upstream longitudinal flow path via a partition wall.   The fluid flows in from the non-sealed vertical flow path of the honeycomb structure, and sequentially flows through the upstream vertical flow path, the wraparound portion, the downstream vertical flow path, and the transverse flow path. The heat exchange structure according to claim 1, which flows out from a hole formed in the outer wall.   The fluid flows in from a hole formed in the outer wall, and flows in the transverse channel, the upstream longitudinal channel, the wraparound portion, and the downstream longitudinal channel in this order to seal the honeycomb structure. The heat exchange structure according to claim 1, which flows out from a longitudinal channel that is not formed.   The heat exchange structure according to any one of claims 1 to 3, wherein the transverse channel is formed by a gap between a sealed partial material of the longitudinal channel and an end of the partition wall.   The heat exchange structure according to any one of claims 1 to 3, wherein the transverse channel is formed by a hole communicating with the partition wall.   The heat exchange structure according to any one of claims 1 to 5, wherein the transverse channel is formed by perforating the partition walls after the honeycomb structure is integrally formed.   The heat exchange structure according to any one of claims 1 to 6, wherein the sealed longitudinal flow path forms a striped pattern on one end face of the longitudinal flow path of the honeycomb structure.   The heat exchange structure according to any one of claims 1 to 6, wherein the sealed longitudinal flow path forms a lattice pattern on one end face of the longitudinal flow path of the honeycomb structure.   The heat exchange structure according to any one of claims 1 to 5, wherein the sealed longitudinal flow path forms a bent linear pattern on one end face of the longitudinal flow path of the honeycomb structure. .   The heat exchange structure according to any one of claims 1 to 5, wherein the sealed longitudinal flow path forms a branched linear pattern on one end face of the longitudinal flow path of the honeycomb structure. body.   The heat exchange structure according to any one of claims 1 to 10, wherein a hole formed in the outer wall is formed in one outer wall surface.   The heat exchange structure according to any one of claims 1 to 10, wherein the hole formed in the outer wall is formed in two or more outer wall surfaces.   The heat exchange structure according to any one of claims 1 to 12, wherein the longitudinal channel has a cross-sectional shape selected from a triangle, a quadrangle, a hexagon, and a combination thereof.   The outer wall of the heat exchange structure is extended, and the encircling part is composed of a cavity at the end of the end of the longitudinal channel formed by sealing the end of the outer wall. The heat exchange structure according to item.   A part of the longitudinal flow path is sealed at one end face in the longitudinal flow path direction of the honeycomb structure, and the entire longitudinal flow path is sealed at the other end face, and the wraparound portion is sealed with the other sealing face. The heat exchange structure according to any one of claims 1 to 13, wherein the heat exchange structure is formed by a transverse hole penetrating a partition wall in the vicinity of an end portion of the longitudinal channel, intersecting with an extending direction of the transverse channel.   16. The heat generation unit according to claim 1, wherein the heat generating unit is a catalyst that generates heat by a chemical reaction of a heat generation component contained in the fluid, and the catalyst is supported on a partition wall in the vicinity of the wraparound portion. Heat exchange structure.   The heat generation means is a catalyst that generates heat by a chemical reaction of a heat generation component contained in the fluid, and the catalyst is filled in a flow path near the wraparound portion. The heat exchange structure as described.   The heat exchanging structure according to any one of claims 1 to 15, wherein the heat generating means is an electric heater disposed at or near the wraparound portion.   The heat exchange structure according to any one of claims 1 to 15, wherein the heat generating means is a combustion burner disposed at or near the wraparound portion. Using the ceramic material composition that hardens by firing, the honeycomb structure is integrally formed, and then a plurality of transverse channels that connect the longitudinal channels are provided, and then the ceramic material composition is fired. The manufacturing method of the heat exchange structure of any one of Claim 1 thru | or 15.

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