WO2005075800A1

WO2005075800A1 - Reactor with heat exchange function

Info

Publication number: WO2005075800A1
Application number: PCT/JP2005/001416
Authority: WO
Inventors: Akira Obuchi; Junko Uchisawa; Akihiko Ooi; Tetsuya Namba; Norio Nakayama; Atsushi Ogata
Original assignee: National Institute Of Advanced Industrial Science And Technology
Priority date: 2004-02-05
Filing date: 2005-02-01
Publication date: 2005-08-18
Also published as: JPWO2005075800A1

Abstract

A reactor capable of providing a high energy-saving property comparable with a self-heat exchange type reactor and remarkably reducing pressure loss and suitably usable for easily heat-regenerable diesel particulate filter (DPF) by disposing a filter in a flow passage inside the reactor. The reactor moves heat from the downstream side of one fluid to the upstream side of the other fluid between two fluids by installing a heating means such as a catalytic layer and an electric heater in one or both of the flow passages of a two-fluid counter-current flow type heat exchange structure having two flow passages partitioned by a heat transfer surface, desirably a heat transfer surface formed of a waveform transmitting body, desirably at the center part thereof. Also, the filter may be installed in the flow passage of the reactor at the same position as the heating means and/or near the heating means.

Description

Specification

Reactor with heat exchange function

Technical field

The present invention relates to a reactor having a heat exchange function, and particularly to a suitable technology applicable to the field of thermal engineering for saving energy consumption and the field of environmental technology for purifying air and exhaust gas. Things.

Background art

[0002] A combination of a chemical reactor and heat exchange is widely used as a means for increasing energy efficiency in a chemical reaction process. However, in the case of a device in which the chemical reactor and the heat exchange are separated, it is difficult to increase the heat recovery rate because the heat loss at these connecting portions is large and the overall shape is generally large. For this reason, a device that integrates heat exchange and a reactor is being used for the first time.

[0003] Such a conventional heat exchange reactor is of a self heat exchange type in which heat is exchanged between the upstream and downstream of the same fluid containing a reactant. In the case of a normal heating reactor, the downstream force with the increased temperature is designed to transfer heat to the upstream where preheating is required. In addition, as shown in Fig. 1, a self-heat-exchange type thermal reactor is provided with a heat transfer surface inside the heat exchanger, which is provided with an end on a partition wall, and in which the fluid containing the reactant is inverted. Thus, there has been proposed a configuration in which the upstream and downstream sides of the fluid flow in opposite directions on the mutually opposite surfaces of the partition wall to provide a counterflow heat exchange shelf function (for example, see Non-Patent Document 1). However, such a flow path configuration has a problem that the pressure loss becomes extremely high because the flow path length inside the narrow heat exchange becomes long.

[0004] In addition, as a solution to such a disadvantage, as shown in FIG. 2, a fluid inlet and a fluid inlet and a fluid inlet are provided at substantially the center in the longitudinal direction of a heat-transfer partition for heat exchange. A reactor having a structure in which an outlet is provided and the fluid is reversed at both ends in the longitudinal direction of the partition wall has also been proposed (for example, see Patent Document 1). In this method, a fluid containing a reactant is naturally divided into two inside a structure having a heat exchange function in a reactor, and flows toward each end. Therefore, compared to the case of FIG. 1 in which the entrance and exit are provided at the end of the heat exchanger structure, The flow path length and the flow rate of each part are halved, and the pressure loss of the fluid can be reduced. However, in this method, it is difficult to equalize the temperatures in both reaction zones because there are two main reaction zones where the temperature is maximized at both ends of the reactor. In particular, when the fluid is a gas, its viscous resistance increases as the temperature rises, so if one of the reaction areas becomes slightly higher in temperature than the other, the specific force of the fluid divided into the reaction area decreases, and as a result, As a result, the heat recovery rate on the flow path side is increased, and the temperature of the reaction region is further increased. On the other hand, on the opposite channel side, the heat recovery rate decreases due to the increase of the flow rate, and the temperature of the reaction zone decreases more and more. In other words, such a method in which the flow path is divided inside the heat exchanger has the characteristic that the distribution ratio of the fluid and the difference between the maximum values of the temperatures in both reaction regions are widened. Having. If the fluid passes through the flow path on the low temperature side more, the required reaction rate may not be reached, and the desired reaction rate may not be obtained. Furthermore, since the temperature has two maximum values and the force spreads to the end of the reactor, it may be difficult to efficiently maintain a high temperature in the reaction zone where heat radiation is high.

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2000-189757

Non-Patent Document 1: "Chemical Engineering", edited by Kenji Hashimoto, Baifukan, 1997, p. 79, Disclosure of the invention

Problems to be solved by the invention

[0006] The present invention has been made in view of such a situation of the prior art, and is a compact heat exchanger in which a heat exchanger ^^ and a chemical reactor are integrated, has a high heat recovery rate, and further has a low pressure loss. The purpose is to provide a reactor equipped with Koura Noh.

Means for solving the problem

According to the present invention, the following reactor (1)-(5) is provided.

(1) A reactor having a two-fluid countercurrent type heat exchanger structure having two flow paths separated by a heat transfer surface, wherein a chemical reaction is promoted in at least a part of the flow path where heat exchange is performed. A reactor provided with a heating means for moving the reactor.

(2) The reactor according to (1), wherein the heating means is a catalyst layer.

(3) The reactor according to the above (1) or (2), wherein one fluid is divided into two and then flows countercurrent to each other. (4) In the heat exchanger structure, the heat transfer body constituting the heat transfer surface is corrugated, and the two fluids are mainly filled in one of the corrugated portions of the heat transfer body and the gap on the back side thereof in the direction of the corrugated ridge. The reactor according to any one of (1) to (3), wherein the reactor is caused to flow countercurrently along the Z or valley direction.

(5) In each flow path of the two fluids, a heating means in a streamline direction, and a filter for capturing combustible fine particles at the same position and / or in the vicinity of the heating means are arranged. (1) The reactor described in (4) above.

The invention's effect

[0008] According to the present invention, the heat generated by the chemical reaction and the heat added to continue the chemical reaction are recovered by the discharged fluid power, and re-supplied to the main part where the chemical reaction occurs. Thus, a highly energy-saving reactor with little or no auxiliary heating is provided.

Since the reactor of the present invention can reduce both the flow rate and the flow path length of the portion having the heat exchange function by half compared with the conventional self-heat exchange type reactor in which only one continuous flow path is used, pressure loss is reduced. Can be significantly reduced, and the energy required for pumping can be saved in this respect as well.

In addition, the reactor of the present invention has a higher temperature in the main reaction region than a conventional self-heat exchange type reactor in which a fluid is naturally divided into two inside a structure having a heat exchange function in the reactor. Is less likely to be uneven, and heat loss due to heat radiation can be reduced.

The reactor of the present invention is a low-concentration organic component treatment device such as a deodorizing device or an automobile exhaust gas converter with high energy efficiency, or a particulate matter reduction device (DPF) that captures and removes particulate matter discharged from a diesel engine. Brief description of drawings that are preferably used for applications such as

FIG. 1 is a schematic configuration diagram of a conventionally known self-heat exchange type reactor having a flow path reversing part at one end.

[FIG. 2] FIG. 2 is a schematic configuration diagram of a conventionally known self-heat exchange type reactor having flow passage reversing portions at both ends. FIG. 3 is a basic configuration diagram of the reactor of the present invention, and is a cross-sectional view of a main part of a reactor having a two-fluid countercurrent heat exchange function. FIG. 3 (a) shows an example in which a catalytic reaction is used as a heating means. FIG. 3 (b) shows a case where an electric heater is used as a heating means.

[FIG. 4] FIG. 4 is a configuration diagram of another reactor of the present invention, and has a two-fluid countercurrent type heat exchange function to which an introduction path for causing substantially equivalent fluids to flow in opposite directions is added. It is principal part sectional drawing of. FIG. 4 (a) shows one fluid to be introduced after being divided into two. Fig. 4 (b) shows a multi-cylinder engine in which half of the cylinder exhaust gas is introduced collectively.

FIG. 5 is a configuration diagram of still another reactor of the present invention, and is an oblique perspective view of a main part of a reactor having a two-fluid countercurrent heat exchange structure using a corrugated heat transfer body. FIG. 5 (a) shows a corrugated heat transfer body and a catalyst layer installed thereon. FIG. 5 (b) shows the main part of the reactor containing the structure of FIG. 5 (a) and the fluid flow path.

FIG. 6 is a configuration diagram of still another reactor of the present invention, which has a two-fluid countercurrent heat exchange structure having a particulate matter reduction function using a corrugated heat transfer material combined with a filter material. It is principal part sectional drawing of a vessel. FIG. 6 (a) shows a case where a part of the gap of the corrugated heat transfer material is filled with a filter material. Fig. 6 (b) shows a flat filter material sandwiched between two spacers to increase the geometric filtration area. FIG. 6 (c) shows a combination of a flat filter material and a spacer having a form in which a fluid flow collides in one direction of the filter.

Explanation of symbols

1 container

2, 2, 2, 2 "fluid inlet

3, 3, 3 ”fluid outlet

4, 4, fluid reversal part

5 Catalyst layer

6 Heat transfer partition supporting catalyst

7 Electric heater and its power supply

8 Three-way joint 9 Flow control valve

10 Engine

11 Corrugated heat transfer

12 The front of the container containing the corrugated heat transfer

13 The back of the container containing the corrugated heat conductor

14 Huino Letter

15 Flat filter material

16 Spacer

17 Spacer with function to bend fluid flow

BEST MODE FOR CARRYING OUT THE INVENTION

[0011] Hereinafter, several embodiments of a reactor having a heat exchange function according to the present invention will be described in detail with reference to the drawings, but the present invention is not limited to these embodiments. Various changes are possible as long as the gist of the present invention is included.

(First Embodiment)

FIG. 3 is a schematic sectional view of a main part of a reactor having a two-fluid countercurrent heat exchanger function according to the first embodiment of the present invention.

FIG. 3 (a) shows an example of the reactor of the present invention based on the multi-tube cylindrical heat exchanger structure. The inlet 2 and the outlet 3 respectively show the inside of the reaction vessel 1 from left to right in this figure. And the inlet and outlet of the first fluid containing the reaction component flowing therethrough. On the other hand, the inlet 2 ′ and the outlet 3 ′ are separated from the flow path of the first fluid by the heat transfer surface, and are the entrances and exits of the second fluid flowing inside the vessel 1 to the right and left in this figure. Reference numeral 5 denotes a catalyst layer provided in a portion near the center of the flow path of the first fluid, and is an example in which the catalyst layer is used as heating means for the reactor in the present invention.

Next, the operation of this device will be described. A first fluid, such as a mixture of hydrocarbon and air, having a composition capable of causing an exothermic reaction by the catalyst layer 5 enters the container 1 from the fluid inlet 2 and flows to the right. As a result of the reaction being caused in the catalyst layer 5 in the middle of the flow path, heat is generated in this portion, whereby the catalyst layer 5 and the first fluid are heated. While this heated first fluid flows from the catalyst layer 5 to the fluid outlet 3 (section R in the figure), the first fluid force heat transfer surface, and furthermore, the heat transfer from the heat transfer surface to the second fluid, While the first fluid cools, it flows countercurrently The second fluid is heated. Next, when the second fluid heated in the section flows between the catalyst layer 5 and the fluid outlet 3 ′ (section L in the drawing), the second fluid is more than the first fluid separated by the heat transfer surface. It is hot. Therefore, heat transfer from the second fluid to the first fluid cools the second fluid while heating the first fluid. According to the above-described heat transfer mode, the heat of reaction, which is originally discharged to the outside together with the first fluid, is recovered inside the container 1, and as a result, the catalyst becomes more in comparison with the one-sided plug flow type reactor. The reactor can keep the temperature of the layer 5 high by the reaction heat.

[0014] The type of catalyst used in the catalyst layer 5 is appropriately determined depending on the reaction components contained in the fluid, and the type of the catalyst is not limited. For example, when the reaction components are hydrocarbons and oxygen in the air, catalysts in which noble metal fine particles such as Pt, Pd, Rh, and Ir are supported in the form of fine particles on a high surface area material such as alumina or zeolite, MnO, Co O, NiO, Cu

2 3 4

It is preferable to use an oxide having high oxidation catalytic activity, such as a metal oxide such as o and a composite oxide thereof.

[0015] In order to maximize the heat recovery rate and maximize the temperature in the catalyst layer 5, the position of the catalyst layer 5 in the streamline direction is most effectively located near the center of the countercurrent. The central force may also be shifted. The thickness of the catalyst layer 5 in the flow channel direction is short in order to improve the heat recovery rate, and is more desirable, but long in order to improve the reaction rate, and is more desirable. May be determined based on a balance between the two conditions. In this embodiment, the catalyst layer 5 is filled in the flow channel, but may be coated on the heat transfer surface. Further, in the present embodiment, only the first fluid contains a reaction component, and the catalyst layer is disposed only in a part of the first fluid flow path. However, the same or different reaction components are also contained in the second fluid together with the first fluid. A catalyst layer that contains and promotes the reaction may be disposed in a part of the second fluid flow path. In this case, it is most effective to arrange both catalyst layers at the center, but they may be intentionally shifted individually in the streamline direction. In addition, other forms capable of countercurrent flow, such as a force plate fin type using a multi-tube cylindrical type or a vortex type, may be used as the heat exchange structure.

FIG. 3 (b) shows the use of an electric heater 7 installed in a flow path without using the above-described catalytic reaction as a heating means. The heating by the electric heater 7 and the heat recovery The temperature of the portion where the thermal heater 7 is installed can be effectively raised, thereby providing a reactor for promoting the thermal reaction. In the present embodiment, the electric heater 7 is arranged only in the flow path of the first fluid, but may be arranged in a part of the second fluid in the same manner. In this case as well, it is most effective to arrange the electric heater in the vicinity of the center in the streamline direction in order to maximize the heat recovery rate. It is also possible to use other physical heating means such as microwaves, electromagnetic induction heating, etc., which can be used only with an electric heater. Good.

(Second Embodiment)

FIG. 4 is a schematic cross-sectional view of a reactor according to another embodiment of the present invention.

The reactor of this form is originally a single or substantially equivalent fluid divided into two, and used as first and second fluids which flow countercurrently. That is, in FIG. 4 (a), a piping structure is provided in which the reaction fluid entering from the fluid inlet 2 is divided into two at the three-way joint 8 and then guided to the two fluid inlets 2 ′ and 2 ″ of the container 1. In addition, the catalyst layer 5 is disposed in the middle of both flow paths of the first and second fluids in the heat exchange structure, whereby a heat recovery mechanism similar to that described in the first embodiment is provided. Thereby, the temperature near the catalyst layer 5 can be increased.

This structure has two main reaction areas where the temperature reaches a local maximum, compared to a conventional self-heat exchange type reactor in which the fluid naturally divides into two inside the structure having heat exchange capability inside the reactor. Since it is a common location in the flow path, the temperature is less likely to be uneven between the two flow paths. Further, since the maximum value of the temperature is limited to one location in the center of the reactor and it is easy to take a heat retaining means, the heat loss due to heat radiation can be further reduced. In the present invention, as shown in FIG. 4 (a), a flow rate control valve 9 is appropriately provided in one or both of the flow paths divided by the three-way joint 8, so that the fluid inlets 2 'and 2 " The distribution ratio of the input reaction fluid may be set to be equal or another intended ratio.

FIG. 4 (b) shows the exhaust gas of the engine 10 in which the reaction fluid has an even number of cylinders. The exhaust gas from half the cylinders is the first fluid, and the exhaust gas from the remaining half cylinders is the second fluid. It is equipped with a piping structure for flowing countercurrent to each other. The flow path of both fluids is the same as in Fig. 4 (a). The catalyst layer 5 is provided inside. By doing so, the first and second fluids having substantially the same composition and flow rate can be introduced into the reactor in countercurrent to each other without a mechanism for adjusting the distribution ratio such as the flow rate control valve 9. Can be. As a result, heat is mutually recovered between the upstream and downstream of the two divided exhaust gases, and the temperature of the central portion of the reactor can be increased.

Thus, according to this structure, unlike the conventional self-heat exchange type reactor in which the fluid is naturally divided into two inside the structure having heat exchange in the reactor, the fluid in the reactor is Since there is no danger of a decrease in the heat recovery rate due to uneven flow rates between the two flow paths, it is possible to exhibit performance close to the maximum performance that can be expected.

(Third Embodiment)

FIG. 5 is a perspective view showing another embodiment of the reactor according to the present invention.

FIG. 5 (a) shows a rectangular heat conductor such as a stainless steel plate having heat resistance formed into a corrugated shape, and a catalyst layer 5 disposed near the center in the longitudinal direction. Most desirably, adjacent flat portions of the corrugations are formed so as to be parallel to each other at regular intervals. In order to achieve this, a material having heat resistance and air permeability, such as stainless steel wire mesh, may be interposed as a spacer in the whole or a part of the corrugated space. FIG. 5 (b) shows a case where the corrugated heat transfer body 11 having the catalyst layer 5 is housed in a rectangular parallelepiped container 1. The container 1 is provided with a first fluid inlet 2 'and an outlet 3' force near both ends in the longitudinal direction of the upper surface in FIG. 5 (b), and a lower surface is provided on the lower surface behind the outlet 3 'and the inlet 2', respectively. Two fluid inlets 2 "and outlets 3" are provided. On the front and back surfaces of FIG. 5B, the gap between the container 1 and the corrugated heat transfer body 11 is sealed with a suitable sealing material.

Next, the operation of the reactor of this embodiment will be described. The first and second fluids entering from the fluid inlets 2 'and 2 "respectively form the ridges (or valleys) of the waveform in the voids on one side of the waveform and the opposite side across the waveform heat transfer body 11 In the case where both fluids contain a component that causes an exothermic reaction due to the action of the catalyst layer 5, the fluid flows from the fluid inlet 2 '(and the fluid outlet 3 "). In the section of the catalyst layer 5, heat transfer occurs from the second fluid (the hatched arrow in the figure) to the first fluid (black arrow), and the section from the catalyst layer 5 to the fluid outlet 3 '(and the fluid inlet 2 "). In the reverse, heat transfer occurs to the first fluid force and the second fluid, ie, both parts At the same time, the fluid force that has already passed through the catalyst layer 5 and reacted has transferred heat to the fluid that is about to flow into the catalyst layer 5. As a result, by preheating both fluids, the temperature in the catalyst layer 5 can be kept high, and the reaction can proceed smoothly. In this embodiment, a catalytic reaction was used as the heating means, but an electric heater or other physical heating means was arranged in the flow path of the first and second fluids or any of the fluids as in the first embodiment. It may also be used as a thermal reactor! / It may also have both catalytic reaction and physical heating means!

(Fourth Embodiment)

FIG. 6 is a cross-sectional view of a reactor according to another embodiment of the present invention, which is perpendicular to a plane portion of the corrugated heat transfer body 11.

FIG. 6 (a) shows a filter in which a combustible fine particle floating in a gas can be captured in a space near the center of the corrugated heat transfer body 11. FIG. Although not shown, the filter 14 carries a catalyst having a function of promoting the heat generation by reacting the reaction components contained in the fluid, or in the same section where the filter is disposed, the corrugated heat transfer material 11 A physical heating means such as an electric heater capable of directly heating the filter is disposed on both sides of the filter.

[0022] For example, when a gas containing carbon fine particles (an example of combustible fine particles) such as diesel engine exhaust gas is introduced from both fluid inlets 2 'and 2 "of the reactor, the carbon fine particles are captured by the filter 14. It is necessary to add a hydrocarbon such as propane or ethylene or H to the process gas containing oxygen to make the catalyst work, or use an electric heater.

2

When the filter 14 is heated by the above, the temperature of the filter 14 can be easily raised by the generated heat and the heat recovery action in the reactor. Thereby, the carbon fine particles are oxidized and removed, and the filter function can be maintained.

In the form of FIG. 6 (a), the filter 14 simply fills a part of the flow path, but may be as shown in FIG. 6 (b). That is, after a flexible flat filter material 15 is sandwiched between spacers 16 such as a stainless steel wire mesh having heat resistance and air permeability, it is stored in each gap of the corrugated heat transfer body 11. The downstream end of the flat filter material 15 is longer than the spacer 16 arranged on the upstream side in the longitudinal direction of the waveform, and the upstream end of the flat filter material 15 is arranged on the downstream side. Upstream end of flat filter material 15 longer than 16 And the downstream end are alternately brought into close contact with the heat transfer member surfaces on both sides of the gap. By adopting such a structure, a flow path that passes through the flat surface of each filter material is formed, increasing the geometrical filtration area as compared with Fig. 6 (a), and consequently the filter Pressure loss can be reduced. The spacer 16 may also have a function as a catalyst support structure or an electric heater.

Further, as shown in FIG. 6 (c), a heat-resistant and air-permeable switch having a periodic structure between the two flat filter members 15 that bends the flow of the fluid in the direction of colliding with the filter surface. It may be used with a spacer 17 in between. As such a spacer, a plain-woven stainless steel wire mesh, a corrugated metal plate having many small holes, or the like is used. With this structure, the flammable particulates are captured by the collision of the fluid on one surface of the filter, but the pressure loss can be reduced compared to the case of Fig. 6 (a) where the fluid penetrates the filter. it can. Also in this case, the catalyst is supported on the filter material 15, the surface of the heat transfer body in contact with the filter material 15, or the surface of the spacer 17 having a function of bending the fluid flow, or a spacer having a function of bending the fluid flow. 17 can also be used as a heating means by also using an electric heater!

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1

[0025] As shown in Fig. 4 (a), a fluid is provided with a pipe structure for dividing one fluid into two and flowing in countercurrent to each other, and has a corrugated stainless steel heat transfer body and flow path form as shown in Fig. 5. Then, a heat exchange reactor was prepared in which a heat-resistant fiber piece carrying an oxidation catalyst was disposed at a position corresponding to the filter material in FIG. 6 (c).

In other words, a heat transfer plate was fabricated by bending a strip of stainless steel thin plate having a thickness of 0.03 mm, a width of 300 mm, and a length of more than 1600 mm 39 times at right angles to the longitudinal direction at 40 mm intervals. On one side of this corrugated structure, a 50-150 mm point from one end in the longitudinal direction of the corrugated structure is a platinum catalyst-carrying 0.25 mm thick, 80 mm long and 100 mm wide heat resistant at 1100 ° C. Twenty pieces of plain woven fiber made of mullite having were placed between the corrugated peaks (20 pieces) of the heat transfer structure. Similarly, 19 pieces of fiber having the same composition and the same dimensions were sandwiched on the opposite surface of the corrugated structure at the opposite end force in the longitudinal direction of 50 to 150 mm. The platinum catalyst used supported 10% by weight of Pt fine particles with respect to γ-alumina.The total weight of these components was 97 g of mullite fiber pieces, 7.2 g of γ-alumina, and 0.72 g of Pt. .

Next, a stainless steel plain weave wire (0.45 mm in wire diameter, 8 mesh) (thickness: about lmm) was placed between the flat surfaces of the corrugated structure in places where there was no fiber piece as a spacer. In addition, a stainless steel plain woven wire mesh with a wire diameter of 0.25 mm and 16 mesh (thickness of about 0.5 mm) was sandwiched between the fiber pieces. Further, the corrugated structure, the fiber piece supporting the platinum catalyst, and the wire mesh spacer are housed in a stainless steel container having a thickness of 0.6 mm and a rectangular parallelepiped (inner size of 40 mm x 47 mm x 300 mm), and a heat exchange type reactor is used. This was the No. 1 reactor.

As shown in Fig. 5, the reactor was provided with rectangular openings of 10x47mm at four points where the longitudinal force at both ends was about 20mm, and a circular pipe with a diameter of 19mm was partially formed in each of these openings. It was cut into a shape and attached so that it could be covered, thereby providing a fluid entrance and exit.

Using the first reactor, the flow direction was such that the portion (catalyst layer) between the fiber pieces supporting the catalyst was closer to the outlet side than the center in the longitudinal direction of the reactor. — Ethylene removal rate and heat recovery performance were investigated when simulated contaminated air containing 0.13% ethylene was flowed at a flow rate of 30-180 L / min. Table 1 shows the obtained results.

[Table 1]

Processed air Ethylene theoretical rise inlet temperature Outlet temperature Central part Ethylene heat recovery rate Pressure loss Runoff ¹ /% Temperature * / ° c / ° c / ° c Temperature / removal rate /% / / mmAq

30 0.207 1 14 24 54 346 99.6 65 28

30 0.153 84 24 58 323 99.7 72 27

30 0.099 55 25 59 280 99.6 78 25

30 0.077 42 25 55 214 99.3 78 23

30 0.056 31 25 51 204 98.8 83 21

30 0.045 24 25 47 169 97 83 19

61 0.098 53 24 48 245 97 76 53

61 0.078 42 24 49 224 97 79 51

60 0.056 29 25 46 183 95 82 47

120 0.096 50 24 54 214 94 74 141

176 0.127 67 25 68 236 95 68 281

* Temperature rise of treated air expected from the amount of heat generated in bottles in which ethylene of the relevant concentration has been completely oxidized

** Heat recovery rate-(Central part temperature-Inlet temperature-Theoretical rise temperature) / (Central part temperature-Inlet temperature) * 100 In these reactions, the reactor cannot be externally heated except at the start of the reaction. The spontaneous catalytic reaction could be maintained by maintaining the temperature of the reaction layer only by the heat of reaction generated by the catalytic oxidation reaction progressing inside. From Table 1, a flow rate of about 30 (space velocity = 320011- ^1), 60 (same 6400H-, 120 (same 12800h-, 176L / min (in terms of the 18800H-, ethylene removal rate, respectively up 99.7, 97, 94, 95%.

The ethylene concentrations at which spontaneous catalytic combustion can be continued are 0.045, 0.056, 0.096, and 0.127%, respectively, all of which are low concentrations that cannot be realized with a normal catalyst layer without a heat recovery function. In addition, the outlet temperature is much lower than the central temperature, and it is easily assumed that heat moves from downstream to upstream of the catalyst layer. The reason why the difference between the outlet temperature and the inlet temperature is smaller than the theoretical rise temperature is that there is heat loss due to heat conduction to the reactor and convection to the air around the reactor other than the amount discharged together with the treated air. It is. Even taking these heat losses into account, the maximum heat recovery at each flow rate reached as high as 83, 82, 74 and 68%. Furthermore, the differential pressure (pressure loss) before and after the reactor was as small as 19-28 mmAq at a flow rate of 30 L / min, and was only 281 mmAq at a flow rate of 176 L / min. Example 2

[0029] Toluene removal rate when simulated contaminated air containing 0.02-0.06% of toluene and flowing at a flow rate of about 60 to 122 L / min using the first reactor in the same flow direction as ethylene. And heat recovery performance. Table 2 shows the obtained results.

[0030] [Table 2] Process air

Toluene hydrogen Theoretical rise Inlet temperature Outlet temperature Central part Toluene Heat recovery rate "Pressure loss

¾m / L-min "

1 A /% temperature * / ° c / ° c / ¾ temperature / ° C removal rate /// mmAq

61 0.060 0.00 45 28 67 395 97 88 84

61 0.050 0.00 74 28 64 348 96 77 78

121 0.059 0.00 87 27 80 377 96 75 228

122 0.060 0.50 137 27 88 496 98 71 267

122 0.040 0.50 106 27 77 404 97 72 235

122 0.021 0.50 77 27 74 333 96 75 213

122 0.020 1.00 127 27 83 464 98 71 256

* The temperature rise of air expected from the amount of heat generated when toluene and hydrogen at the relevant a degree are completely oxidized ** Heat recovery rate = (central temperature-inlet temperature-theoretical boundary; ¾degree) / (central temperature (Temperature-inlet conductivity): * ¹⁰⁰

In this example, the result of adding hydrogen to the processing air for auxiliary heating is also shown.

From the results of the spontaneous catalytic oxidation with zero hydrogen concentration, it was found that high removal rate, low spontaneous catalytic oxidation concentration, and high heat recovery were achieved for toluene as well as for ethylene. At a flow rate of 122 L / min, it was confirmed that 97% or more of toluene could be removed at low concentrations of 0.040% and 0.020%, respectively, by adding hydrogen at 0.5% or 1.0%.

Example 3

[0032] In order to verify that the reactor having the structure shown in Fig. 6 (c) can remove particulate matter (PM) discharged from the diesel engine, a second reactor was manufactured. The piping structure of this second reactor and the configuration, shape, and dimensions of the reactor body are almost the same as those of the first reactor. However, the width of the mullite fiber pieces on both sides of the corrugated structure was 40 mm (total weight used: 36 g), and Pt (total weight: 0.36 g) and MoO (0.36 g) were supported as catalysts there.

Three

This was placed in the range of 130 to 170 mm from the longitudinal end of the corrugated structure, that is, in the center of the reactor. In addition, each of the 16-mesh wire meshes arranged in a certain part of the fiber piece has γ- Lumina-supported Pt was coated (total Pt weight = 0.17 g, γ-alumina total weight = 1.7 g). Using this No. 2 reactor, a part of the exhaust gas generated when a diesel vehicle equipped with a 2180 cc diesel engine was driven on a chassis dynamometer at a vehicle speed of 60 km / h was introduced. In addition, the change in PM collection rate and pressure loss over time when hydrogen was added and the inside was heated by catalytic combustion was examined. Table 3 shows the obtained results.

[Table 3] Exhaust gas flow rate Hydrogen Rise rise Inlet temperature Outlet temperature Center PM heat recovery rate Pressure loss

/ L-min / temperature c, c / ¾ temperature / ° c removal rate /% / mmAq

45 1.00 82 80 133 487 50 80 106 (stable)

45 0.90 74 82 141 493 48 82 108 (stable)

45 0.80 66 84 137 456 50 82 110 (stable)

45 0.59 49 84 126 380 51 84 1 14 (Up)

60 1.1 1 91 92 166 585 46 82 141 (stable)

* Temperature rise temperature of process air expected from the amount of heat generated when this κ¾ degree of hydrogen is completely oxidized ** Heat recovery rate = (Central part temperature-Inlet temperature-Theoretical rise temperature) / (Central part temperature-Inlet temperature ): * 100

[0034] The ΡΜ trapping rate is obtained by measuring the 結果 concentration before and after the reactor using an instantaneous fine particle mass measuring device (ΤΕΟΜ) and also estimating the force. It is confirmed that it has the same high heat recovery as the first reactor and captures 50% of ΡΜ. In addition, the change over time of pressure loss, which is an indicator of the accumulation status inside the device, is stable at an exhaust gas flow rate of 45 L / min at a central temperature of 456 ° C or higher, and when the hydrogen concentration is lowered, the temperature becomes 380 ° C. Only after reaching ° C did it show a remarkable upward trend. In other words, if the central part temperature is 456 ° C or higher, it can be assumed that PM oxidation proceeds at a sufficiently high rate and the amount of deposited PM does not increase, and continuous collection and removal of PM by oxidation are possible. You. Similarly, when the exhaust gas flow rate was 60 Lmin, it was confirmed that if the temperature in the central part was raised to 585 ° C, continuous collection and removal of the acid were possible.

Claims

The scope of the claims

[1] A reactor having a two-fluid counter-current heat exchange structure having two flow paths separated by a heat transfer surface, for promoting a chemical reaction in at least a part of the flow path where heat exchange is performed A reactor provided with a heating means.

[2] The reactor according to claim 1, wherein the heating means is a catalyst layer.

[3] The reactor according to claim 1 or 2, wherein a single fluid is divided into two and then flows countercurrent to each other.

[4] The heat transfer body constituting the heat transfer surface in the heat exchanger structure has a waveform, and the two fluids

11. The method according to claim 11, wherein one of the corrugated portions of the heat transfer body and a void portion on the back side thereof are countercurrently flown along the ridge direction and the Z or valley direction of the waveform.

3. The reactor according to item 1 or 3.

[5] In each flow path of the two fluids, a heating means in a streamline direction, and the same position and

5. The reactor according to claim 1, wherein a filter for capturing combustible fine particles is arranged at or near Z.