JP2009000592A - Reactor and reaction system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reactor in which by-products are restrained from being produced in a confluence part of a plurality of reaction solutions, the reaction yield of which is made high and the output of which is increased. <P>SOLUTION: The reactor is composed of: the confluence part 1 into which two different fluids 5, 6 are made to flow; a mixing flow passage 3 for mixing two different fluids with each other; a diameter-reduced part 2 for connecting the confluence part 1 to the mixing flow passage 3; and a reaction flow passage 4 for reacting the mixed fluid 7. The hydraulic equivalent diameter of the confluence part 1 is made larger than that of the mixing flow passage 3. In the confluence part 1, the Reynolds number is set at <2,300 to form a laminar flow. In the mixing flow passage 3, the Reynolds number is set at ≥2,300 to form a turbulent flow. The hydraulic equivalent diameter of the reaction flow passage 4 is made larger than that of the mixing flow passage 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a reactor and a reaction system in fields such as chemical synthesis and chemical analysis, and more particularly, to a structure of a fluid mixer and a reactor in which a liquid or a gas is mixed and reacted.

  In recent years, in the field of chemical synthesis and chemical analysis, in order to shorten reaction time and suppress side reactions, it has been manufactured by micro processing (MEMS: Micro Electro Mechanical System) technology, and has a cross-sectional dimension of tens to hundreds of μm. The fluid mixer that has started to be used.

  Such a fluid mixer is called a micromixer or a microreactor. In the micromixer, since the hydraulic equivalent diameter of the flow path is small, the dimensionless number representing the ratio between the inertia force and the viscous force of the fluid, that is, the Reynolds number is small, and the flow is a laminar flow. Therefore, when a plurality of different liquids are mixed, the mixing proceeds by molecular diffusion (see, for example, Non-Patent Document 1).

Next, taking a sequential reaction, which is a typical reaction, as an example, the reaction in the microchannel is examined. In this reaction, substances A and B react to produce main product R,
A + B → R (1)
R + B → S (2)
Further, the main product R and the substance B react to produce a by-product S.

  In a microreactor, two types of fluids that intersect each other are divided into a plurality of fluids, and each fluid is alternately flowed into a microchannel to promote mixing. In general, since the flow is laminar, the two fluids flow in layers.

Here, when the distance between the center lines of the two fluids is defined as the diffusion distance W and the diffusion coefficient of the molecule is D, the time tm required for mixing the two fluids is:
^{tm = W 2 / D ...... (} 3)
It is represented by As the diffusion distance W is reduced, the diffusion time is shortened, so that the mixing of the fluid is promoted.

The reaction rate constants of the main reaction of formula (1) and the side reaction of formula (2) are k ₁ [L / (mol s)] and k ₂ [L / (mol s)], and the concentrations of substances A and B are When the initial concentration in the case of reacting at an equal concentration is C ₀ , the reaction time tr of the product R is
tr = 1 / (k ₁ · C ₀ ) (4)
Given in.

According to Non-Patent Document 1, in the sequential reaction shown in Equation 1 and Equation 2 in the microchannel, as shown in Equation 5, the number of mixed reactions, which is the ratio of the diffusion time of Equation 3 and the reaction time of Equation 4 As φ decreases, the reaction time becomes closer to the rate-determined state compared to the mixing time,
φ = tm / tr = k1 / C0 / W2 / D (5)
The reaction yield, which is the amount of target substance R produced with respect to raw material A, increases.

  Therefore, in order to reduce the number of mixed reactions φ and increase the reaction yield, usually, in a microreactor, the flow path width is reduced or the number of divisions of two kinds of fluids is increased.

In general, since the microreactor has a flow path width of less than 1 mm, the hydraulic equivalent diameter dh shown in Equation 6 is small and the flow velocity V is low.
dh = 4 × channel cross-sectional area / periphery length of channel cross-section (6)
The Reynolds number Re shown in Equation 7 is less than 2,300,
Re = V · dh / ν (7)
The flow is in a laminar state. Here, ν represents the kinematic viscosity coefficient of the fluid.

  Under the turbulent flow condition where Re> 2,300, the diffusion coefficient (turbulent diffusion coefficient) Dt due to the flow disturbance increases to several thousand times or more of the molecular diffusion coefficient Dm. Accordingly, it is shown that when the turbulent flow condition is used even in the channel width of the order of mm, the number of mixed reactions φ becomes small and the reaction yield increases.

  FIG. 9 is a horizontal sectional view showing the structure of an example of a conventional Y-shaped reactor, and FIG. 10 is a horizontal sectional view showing the structure of an example of a conventional multilayer flow reactor.

  In the Y-shaped reactor of FIG. 9, the yield can be increased by micronizing the flow path width corresponding to the diffusion distance W in Equation 5, and in the multilayer flow reactor of FIG. If the interval between the two liquids corresponding to W is micronized, the yield can be increased.

Kawamura et al: Chemical Engineering Society 37th Autumn Meeting, I205, (2005) (Fig. 2 on page 1)

  In the case of mass production of materials using a microreactor, a method called numbering up in which many reactors are arranged in parallel is considered.

  However, in the prior art of FIGS. 9 and 10, in order to increase the reaction yield, the diffusion distance W needs to be several tens of μm, so the flow path width is usually 1 mm or less. In that case, the flow rate of the fluid in the flow path is reduced due to the pressure loss limitation, so the amount of substance production per reactor is assumed to be small, and the numbering up is assumed to be several hundred or more. As the numbering up increases, the number of parts increases, and system reliability and robustness become issues. Against this background, there is a need to reduce the number of numbering up to several tens, increasing the flow rate in the flow path in a turbulent state, improving mixing, and increasing the production volume per unit A way to make it possible is considered.

  In the turbulent flow state, the diffusion coefficient (turbulent diffusion coefficient) Dt due to the flow turbulence increases to several thousand times or more of the molecular diffusion coefficient Dm in the laminar flow state. The number of mixed reactions φ can be reduced, and the reaction yield can be increased. In the case of the Y-shaped channel shown in FIG. 9, it is possible to increase the flow rate while increasing the reaction yield in a turbulent state. If the flow path is made larger than the Y-shaped flow path to reduce the pressure loss and the flow rate is increased, and the flow is a multi-layer flow as shown in FIG. The production volume can be further increased by reducing the interval between the two liquids.

  However, in the case of the multilayer flow reactor shown in FIG. 10, when the two liquids flow into the merging portion having a large flow path width in a turbulent state, the two liquids start to mix and react due to the turbulent flow, and the reaction yield decreases. There is a fear.

  Further, when producing a substance having a long reaction time, if a fluid is flowed in a high-speed turbulent state, the pipe length becomes long and the pressure loss increases.

  Furthermore, in the case of an exothermic reaction, there is a possibility that sufficient temperature control cannot be performed if a fluid is flowed at a high speed.

  The subject of this invention is providing the reactor which suppresses the production | generation of the by-product in the confluence | merging part of a some reaction liquid, raises a reaction yield, and has a large production amount.

  To provide a reactor capable of suppressing the reaction at a confluence portion having a large diffusion distance W, mixing in a mixing channel having a small diffusion distance W, and then starting the reaction in the reaction channel to increase the yield. It is.

  Another object of the present invention is to provide a reactor in which pressure loss does not increase even when fluid is flowed in a high-speed turbulent state.

  Another object of the present invention is to provide a reaction system capable of sufficient temperature control even when a fluid flows at high speed.

  In order to solve the above-described problems, the present invention provides a merging unit that merges a plurality of different fluids, a mixing channel that mixes a plurality of merged fluids, and a contraction unit that connects the merging unit and the mixing channel. In a reactor that reacts a plurality of different fluids, a merging portion where a plurality of fluids merge is a laminar flow channel, and a mixing channel where a plurality of fluids mix is a turbulent flow channel A reactor is proposed.

  In the present invention, in order to suppress the reaction at the merging portion having a large diffusion distance and mix in the mixing channel having a small diffusion distance, a protrusion is formed on at least a part of the inner wall surface of the mixing channel, or An uneven surface is formed on at least a part of the inner wall surface of the mixing channel.

  When the reaction is completed in such a mixing channel, the basic effect of the present invention is sufficient, and thus a special device is not necessarily required for the subsequent reaction channel.

  In the case of having a reaction channel for reacting a plurality of mixed different fluids, the hydraulic equivalent diameter of the reaction channel is made larger than the hydraulic equivalent diameter of the mixing channel. The reaction channel may be branched into a plurality.

  A heat exchanger or a heat source is placed in contact with the reactor to constitute a reaction system. If the cross-sectional shape of the reaction channel is flat, install a heat exchanger or heat source in contact with the reactor so as to face the long cross-sectional surface of the flat reaction channel to improve heat exchange efficiency .

  According to the present invention, the reaction is prevented at the junction where the diffusion distance is large, and after mixing in the mixing channel having a small diffusion distance, the reaction is started in the reaction channel to suppress the side reaction, thereby reducing the pressure loss. Therefore, it is possible to provide a reactor with a high production yield and a high reaction yield.

  In the present invention, a merging portion that divides each of a plurality of different kinds of fluids into a plurality of divided fluids, a mixing passage that mixes the plurality of fluids, a contraction portion that connects the merging portion and the mixing passage, A reactor having a reaction channel downstream of the channel and reacting a plurality of different types of fluids, the Reynolds number of the junction where the plurality of fluids merge is less than 2,300, a laminar flow, and a plurality of A structure in which the Reynolds number in the mixing flow channel downstream of the contracted flow portion where the fluid is mixed is 2,300 or more, is turbulent, and a plurality of protrusions or uneven surfaces are formed on the flow channel wall surface of the mixing flow channel Propose.

  With such a structure, side reactions at the junction are prevented, and the mixing performance at the mixer is enhanced. Therefore, a reactor that produces a product with a high reaction yield and a large production volume can be provided.

  The reaction channel downstream of the mixing unit is proposed to have a structure in which the hydraulic equivalent diameter is larger than the hydraulic equivalent diameter of the mixing channel or is branched into a plurality of branches.

  With such a structure, pressure loss in the reaction section is reduced, the flow rate is increased, and the production volume can be increased.

  Next, with reference to FIGS. 1-8, the Example of the reactor and reaction system by this invention is described.

  FIG. 1 is a horizontal sectional view showing the structure of Example 1 of a reactor according to the present invention.

  The flow path of the reactor 16 according to the first embodiment includes a merging section 1 that allows two different types of fluids 5 and 6 to flow in, a mixing flow path 3 that mixes these two kinds of fluids 5 and 6, and a merging section 1. It consists of the contraction part 2 which connects the mixing flow path 3, and the reaction flow path 4 with which the mixed 2 fluid 7 is made to react.

  Since the hydraulic equivalent diameter dh of the merging portion 1 is larger than the hydraulic equivalent diameter dh of the mixing channel 3, the flow velocity of the merging portion 1 is lower than the flow velocity of the mixing channel 3.

  In the present invention, the Reynolds number Re is less than 2,300 in the merging section 1 for a given flow rate per reactor, resulting in laminar flow conditions. In the mixing channel 3, the Reynolds number Re is 2 , 300 or more, the respective hydraulic equivalent diameters dh are determined so as to satisfy the turbulent flow condition.

  In the contraction part 2, the flow velocity increases in the vicinity of the mixing part, and a region where the Reynolds number Re is 2,300 or more is generated. However, in general, the contracted flow structure has a rectifying effect, so that transition to turbulent flow hardly occurs.

  With the flow path configuration as described above, the merging portion 1 is in a laminar flow state, and mixing of the two fluids is suppressed, so that by-products generated when the diffusion distance is large are suppressed. It becomes turbulent and mixed at high speed.

  The mixed fluid 7 starts the reaction in the mixing channel 3 and the reaction channel 4. After mixing completely, the diffusion distance becomes irrelevant, and it is sufficient that the residence time required for the reaction can be secured.

  Therefore, in the present invention, the hydraulic equivalent diameter dh of the reaction channel 4 is made larger than the hydraulic equivalent diameter dh of the mixing channel 3 in order to reduce the pressure loss of the reaction channel 4. The flow in the reaction channel 4 may be either laminar or turbulent.

  According to Example 1, a reactor with high reaction yield, low pressure loss, high yield and high productivity can be provided.

  FIG. 2 is a horizontal sectional view showing the structure of Example 2 of the reactor according to the present invention.

  Example 2 is the same as Example 1 of FIG. 1 except for the configuration of the reaction channel 4.

  In Example 2, the reaction flow path 4 downstream of the mixing flow path 3 is branched into a plurality of flow paths, and the total cross-sectional area of the plurality of reaction flow paths 4 is equal to the flow break of the mixing flow path 3. Since it is larger than the area, the flow rate of the reaction channel 4 is lower than the flow rate of the mixing channel 3.

  As a result, pressure loss can be reduced. In addition, when the target reaction requires temperature control like an exothermic reaction, since the total heat transfer area is increased by using a plurality of reaction flow paths 4, heat exchange can be performed efficiently.

  According to the second embodiment, it is possible to provide a reactor with high reaction yield and high production volume by high-speed mixing and precise temperature control.

  FIG. 3 is a horizontal sectional view showing the structure of Example 3 of the reactor according to the present invention.

  In general, when the laminar flow 11 upstream of the contracted flow part 2 transitions to turbulent flow after contracted, the turbulent boundary layer 9 is connected to the mixed flow path 3 after contracted flow as shown in FIG. Developed from the inlet 8, the mixing channel 3 is completely turbulent with a run length Ld that is 10 times the hydraulic equivalent diameter dh. That is, in the region of the run length Ld from the mixing flow path inlet 8 to 10 dh, the mixing property is lowered. As a result, the mixability is reduced, and the pressure loss may increase due to an increase in by-products and an increase in the mixing channel length.

  On the other hand, in the present Example 3, the protrusion 14 is installed in the circumferential direction on the wall surface near the inlet of the circular mixing channel 3, and the run length Ld is set by the turbulent vortex 10 generated by the protrusion 14. It is shortened.

  The mixing channel shape and the protrusion shape of the mixing channel 3 are not limited to the example of FIG. FIG. 5 is a cross-sectional view taken along the line AA of FIG. The cross section of the mixing channel 3 may be circular or rectangular, and the protrusions 14 may be installed at one or a plurality of locations in the circumferential direction and the flow direction of the mixing channel cross section.

  According to the third embodiment, high-speed mixing and pressure loss reduction are possible, and a high-yield and high-production reactor can be provided.

  FIG. 6 is a horizontal sectional view showing the structure of Example 4 of the reactor according to the present invention.

  In the fourth embodiment, the uneven surface 15 is formed on the inner wall surface of the entire mixing channel 3.

  According to the fourth embodiment, since the uneven surface 15 is formed, the run-up length Ld can be shortened compared with a smooth wall surface, high speed mixing and pressure loss reduction are possible, and high yield and high production are achieved. Volume reactor can be realized.

  FIG. 7 is a longitudinal sectional view showing the structure of Example 5 of the reactor according to the present invention.

  In Example 5, a reaction system is constructed by installing heat exchangers or heat sources 17 on the upper and lower surfaces of the reactor 16. These heat exchangers or heat sources 17 can be controlled by heating or cooling. The cross-sectional shape of the reaction flow path 4 in the reactor 16 is an elongated rectangle, and the long side of the flow path is installed at right angles to the straight line connecting the flow path center and the heat exchanger or heat source 17 with the shortest distance. ing.

  According to the fifth embodiment, the heat transfer area in the reaction channel 4 is increased, so that the heat exchange efficiency is improved and the reaction yield can be increased by precise temperature control.

  FIG. 8 is a longitudinal sectional view showing the structure of Example 6 of the reactor according to the present invention.

  In Example 6, a reaction system is constructed by installing heat exchangers or heat sources 17 on the upper and lower surfaces of the reactor 16. These heat exchangers or heat sources 17 can be controlled by heating or cooling. The reaction flow path 4 in the reactor 16 is branched into a plurality.

  According to the sixth embodiment, the heat transfer area in the reaction channel 4 is further increased, so that the heat exchange efficiency is improved and the reaction yield can be further increased by precise temperature control.

  Thus, according to the reactor and reaction system of the present invention, in the reaction of a plurality of fluids in a synthesis process such as pharmaceuticals and chemical industrial products, the reaction yield can be increased and the production amount can be increased.

It is a horizontal sectional view which shows the structure of Example 1 of the reactor by this invention. It is a horizontal sectional view which shows the structure of Example 2 of the reactor by this invention. It is a horizontal sectional view which shows the structure of the mixing flow path in Example 3 of the reactor by this invention. It is a horizontal sectional view which shows the structure of the mixing flow path in the conventional reactor. FIG. 6 is a cross-sectional view taken along line AA of FIG. 3, illustrating an example of a mixing channel shape and a protrusion shape in Example 3. It is a horizontal sectional view which shows the structure of Example 4 of the reactor by this invention. It is BB sectional drawing of FIG. 1 which shows the structure of Example 5 of the reactor by this invention. It is CC sectional drawing of FIG. 2 which shows the structure of Example 6 of the reactor by this invention. It is a horizontal sectional view showing the structure of an example of a conventional Y-shaped reactor. It is a horizontal sectional view which shows the structure of an example of the conventional multilayer flow type reactor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Junction part 2 Contraction part 3 Mixing flow path 4 Reaction flow path 5 Fluid A
6 Fluid B
7 Mixed flow 8 Mixing channel inlet 9 Turbulent boundary layer 10 Turbulent vortex 11 Laminar flow 12 Turbulent flow 13 Run-up length 14 Protrusion 15 Concavity and convexity surface 16 Reactor 17 Heat exchanger or heat source

Claims (13)

A plurality of dissimilar fluids, each having a confluence portion for converging a plurality of different fluids, a mixing flow path for mixing the plurality of confluent fluids, and a contraction portion connecting the confluence portion and the mixing flow passages In a reactor for reacting
The merge portion where a plurality of fluids merge is a laminar flow channel,
A reactor characterized in that the mixing channel in which a plurality of fluids are mixed is a turbulent channel. The reactor according to claim 1,
A reactor wherein protrusions are formed on at least a part of the inner wall surface of the mixing channel. The reactor according to claim 1,
An uneven surface is formed on at least a part of the inner wall surface of the mixing channel. Reactor according to any one of claims 1 to 3,
A reactor characterized in that the width of the mixing channel is 1 mm or more and less than 10 mm. A merging portion for merging a plurality of different fluids, a mixing channel for mixing the plurality of merged fluids, a contracting portion for connecting the merging portion and the mixing channel, and a plurality of the mixed different fluids In a reactor having a reaction flow path for reacting and reacting a plurality of different kinds of fluids,
The merge portion where a plurality of fluids merge is a laminar flow channel,
A reactor characterized in that the mixing channel in which a plurality of fluids are mixed is a turbulent channel. The reactor according to claim 5, wherein
A reactor wherein protrusions are formed on at least a part of the inner wall surface of the mixing channel. The reactor according to claim 6,
An uneven surface is formed on at least a part of the inner wall surface of the mixing channel. Reactor according to any one of claims 5 to 7,
A reactor characterized in that the width of the mixing channel is 1 mm or more and less than 10 mm. Reactor according to claims 5 to 8,
A reactor characterized in that a hydraulic equivalent diameter of the reaction channel is larger than a hydraulic equivalent diameter of the mixing channel. Reactor according to claim 5-9,
A reactor characterized in that the reaction flow path is branched into a plurality. Reactor according to claim 10,
A reactor having a width of the reaction channel branched into a plurality of less than 1 mm. A reaction system comprising the reactor according to any one of claims 1 to 11,
A reaction system, wherein a heat exchanger or a heat source is placed in contact with the reactor. A reaction system comprising the reactor according to any one of claims 5 to 11,
The reaction channel has a flat cross-sectional shape,
A reaction system, wherein a heat exchanger or a heat source is placed in contact with the reactor so as to face a long cross-sectional surface of the flat reaction channel.

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