JP2014231038A - Micro mixer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a micro mixer capable of efficiently mixing a plurality kinds of fluids.SOLUTION: A micro mixer comprises a base body 101 having a plurality of micropores functioning as flow paths and a porous body 105. In the micropores, all micropores 102, 102... constituting one group and all micropores 103, 103... constituting another group have one openings in mutually different regions on the surface of the base body 101 and the other openings in another common region on the surface of the base body 101 respectively. The other openings of all the micropores constituting one group and the other openings of all the micropores constituting another group are covered with the porous body 105.

Description

  The present invention relates to a micromixer applicable to a chemical process in which a plurality of types of fluids are mixed in a minute space.

  Microchemical processes that perform chemical processes such as mixing, reaction, extraction, separation, heating, and cooling in microspaces have been proposed, and research on micromixers that enable highly efficient mixing of multiple types of fluids in microspaces Has been made.

  A micromixer is a device that mixes multiple types of fluids in a microscopic space of a micron scale or less. The micromixer has a function of shortening the diffusion distance between the fluids to be mixed. By utilizing this, a fluid mixed with high efficiency can be obtained. As an example, a micro-emulsifier and an emulsification method that can generate an emulsion without using a surfactant are known (Patent Document 1). In addition, a micromixer for producing a mixed liquid is obtained by repeatedly dividing and mixing the liquid flowing in from a plurality of inlets using a three-dimensional flow path formed by combining plates with grooves. It is known (Non-Patent Document 1).

  In such a micromixer, in order to enable mixing in a short time or a liquid that is difficult to mix, for example, the flow of each fluid is divided into a large number on a plane, and the boundary surface between the two liquids is a conventional surface. And the method of improving the mixing and stirring efficiency. However, in order to divide the flow into a large number, it is necessary to form a complicated multi-channel using a precision processing technique, and there is a problem that the manufacturing cost increases.

  Even if multiple channels are used, in a microchannel formed in a plane, the fluid is still laminar, and stirring and mixing is governed by the diffusion of the molecules that make up the fluid. There was room for improvement in efficiency.

JP 2004-81924 A

Savemation Review August 2005, pages 60-63

  The present invention has been made in consideration of the above points, and an object thereof is to provide a micromixer capable of efficiently mixing a plurality of types of fluids.

  A micromixer according to a first aspect of the present invention includes a base body having a plurality of micropores functioning as flow paths, and a porous body, and all the micropores constituting a group among the micropores, And all the micropores constituting the other group each have one opening in a different area on the surface of the base and the other opening in another common area on the surface of the base The other openings of all the micropores constituting the group and the other openings of all the micropores constituting the other group are covered with the porous body. Features.

  The micromixer according to claim 1 is configured such that a plurality of types of fluids that have flowed out from the other opening of the micropores flow out to the external space after passing through the porous body. An infinite number of holes are present at random positions inside the porous body, and a path (space) connected by a plurality of holes serves as a fluid flow path. The flow path inside the porous body has a complicated shape in which branching or merging is repeated randomly, and the fluid flowing therethrough is configured so that the direction of the flow changes finely.

  As each fluid passing through the micropores passes through the pores and flow paths inside the porous body having the above-described configuration, each fluid repeats branching and merging, and vortices are generated in each fluid. As a result, the effect of mixing by vortex is added to the effect of mixing by molecular diffusion, and a plurality of types of fluids are efficiently mixed with each other. Therefore, according to the first embodiment of the present invention, a micromixer capable of efficiently mixing a plurality of types of fluids can be provided.

  The micromixer according to a second aspect of the present invention is the micromixer according to the first aspect, wherein the porous body is in contact with the surface of the substrate in the other common area.

  According to the configuration of the micromixer according to the second aspect, the other opening of the fine hole through which the fluid flows out and the porous body are close to each other. Therefore, compared with the case where both are separated, the movement of the fluid to the porous body can be performed in a short time, and the mixing of the fluids can be started earlier. Therefore, the configuration of the micromixer according to claim 2 is particularly effective for a fluid that can be synthesized only by quickly mixing.

  A micromixer according to a third aspect of the present invention is the micromixer according to the first or second aspect, wherein the other opening of all the micropores constituting the group and the other of the microholes constituting the other group. The opening and the porous body are separated from each other.

  According to the configuration of the micromixer according to the third aspect, since the porous body is disposed away from the base body, it is possible to prevent the base body from being damaged due to contact with the porous body. Therefore, the mixing process of the two liquids when the processing amount is increased can be stably performed.

  A micromixer according to a fourth aspect of the present invention is characterized in that, in any one of the first to third aspects, an average pore diameter of the porous body is smaller than a pore diameter of the micropore.

  According to the configuration of the micromixer according to the fourth aspect, the fluids that have flowed into the porous body from the plurality of micropores in the substrate repeat separation and mixing while passing through the inside of the porous body. At this time, since each fluid is further subdivided, an effect of improving the mixing property between the fluids can be obtained.

  In the micromixer of the present invention, the porous body is arranged in the space where the fluid flows out, and a plurality of types of fluids flowing out from the other opening of the micropores pass through the porous body and then the external space. It is configured to flow into An infinite number of holes are present at random positions inside the porous body, and a path (space) connected by a plurality of holes serves as a fluid flow path. The flow path inside the porous body has a complicated shape in which branching or merging is repeated randomly, and the fluid flowing therethrough is configured so that the direction of the flow changes finely.

  As each fluid passing through the micropores passes through the pores and flow paths inside the porous body having the above-described configuration, each fluid repeats branching and merging, and vortices are generated in each fluid. As a result, the effect of mixing by vortex is added to the effect of mixing by molecular diffusion, and a plurality of types of fluids are efficiently mixed with each other. Therefore, according to the first embodiment of the present invention, a micromixer capable of efficiently mixing a plurality of types of fluids can be provided.

(A) It is sectional drawing which shows typically the structure of the micromixer based on 1st embodiment. (B) It is sectional drawing which shows typically the structure of the fluid control device based on 1st embodiment. (C) It is a top view which shows typically the structure of the fluid control device based on 1st embodiment. It is principal part sectional drawing which shows typically the flow of the fluid in the porous body based on 1st embodiment. (A) It is a perspective view which shows typically the structure of the micromixer based on the modification 1 of 1st embodiment. (B) It is the figure which expanded a part of micro mixer shown to (a). It is a perspective view which shows typically the structure of the micromixer based on the modification 2 of 1st embodiment. (A) It is a perspective view which shows typically the structure of the micromixer based on the modification 3 of 1st embodiment. (B) It is the figure which expanded a part of micro mixer shown to (a).

  Hereinafter, based on a preferred embodiment, the present invention will be described with reference to the drawings. The following embodiments are described by way of example in order to better understand the gist of the invention, and do not limit the present invention unless otherwise specified. In addition, in the drawings used in the following description, in order to make the features of the present invention easier to understand, the main part may be enlarged for convenience, and the dimensional ratios of the respective components are the same as the actual ones. Not necessarily.

<First embodiment>
[Configuration of micromixer]
A configuration of the micromixer 100 according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a diagram schematically showing the configuration of the micromixer 100. The micromixer 100 includes a fluid control device 104 having a plurality of fine holes 102, 102,..., 103, 103,. Sb, a common outflow space Sc, and a porous body 105 are provided.

  Of the plurality of micro holes 102, 102,..., 103, 103,..., All the micro holes 102, 102,... Constituting one group have one opening 102a, 102a,. Are in communication with the inflow space Sa, and the other openings 102b, 102b,. In addition, among the plurality of micro holes 102, 102,..., 103, 103,..., All the micro holes 103, 103,. ,... Communicate with the inflow space Sb, and the other openings 103b, 103b,. The fluid control device 104 forms a part of the base body 101.

  FIG. 1B is an enlarged view of the cross section of the fluid control device 104 of FIG. 1A and schematically shows the configuration of the fine holes 102, 102..., 103, 103. 1C is an enlarged view of the surface of the fluid control device 104 shown in FIG. 1A viewed from the outflow space Sc, and schematically shows the configuration of the fine holes 102, 102... 103, 103. FIG. As shown in FIGS. 1B and 1C, the fine holes 102, 102... 103, 103... Are formed as three-dimensional flow paths without intersecting each other.

  The fine holes 102, 102,... 102 and the fine holes 103, 103,... 103 form a staggered lattice in a plane perpendicular to the length direction of each, that is, staggered most. Arranged so as to be adjacent. Therefore, as compared with the case where all the fine holes are arranged in a lattice pattern as in the conventional structure, each fine hole can be accommodated in a narrow region, so that the mixing property of the fluid flowing through the fine holes is maintained. However, it is possible to further increase the number of flow paths and increase the processing amount.

  Of the substrate 101, the other openings 102b, 102b... (Referred to herein as openings A) of all the fine holes constituting one group and the other of all the fine holes constituting the other group. A surface 104a on which the openings 103b, 103b,... (Hereinafter referred to as the opening B) are present is a surface facing the outflow space Sc. In the surface 104a, the openings A and B are arranged in a staggered pattern. That is, each of the opening A and the opening B forms a plurality of rows arranged in series, and the row of the opening A and the row of the opening B are alternately separated and arranged in parallel. Yes. By arranging the opening A and the opening B in this way, different fluids out of the fluids flowing out from the micropores can be in contact with each other at the same time, so that efficient mixing can be realized.

  When the pore diameter is less than 1 [μm], the pressure loss increases and it becomes difficult to flow the fluid. Moreover, when the hole diameter of a micropore exceeds 100 [micrometers], since the pitch of adjacent micropores becomes large and a diffusion distance increases, mixing property worsens. Therefore, it is desirable that the diameter of the micropores is 1 [μm] or more and 100 [μm] or less. FIG. 1 shows an example in which adjacent micropores are aligned in parallel and bent at the same location, but the shape and arrangement of the micropores can be freely set so long as the micropores do not cross each other. Can be set.

  The inflow spaces Sa and Sb are connected to the external space of the base 101 via connecting portions 106 and 107, respectively. The outflow space Sa is connected to the external space of the base body 101 via the connecting portion 108. In addition, arrangement | positioning of the three connection parts 106-108 in Fig.1 (a) is an example, Comprising: The connection parts 106-108 may be arrange | positioned in any position, as long as it is mutually independent.

  The substrate 101 is made of, for example, an excellent workability and an amorphous member such as glass, or a crystalline member such as silicon or sapphire. In the present embodiment and Modifications 1 to 3 to be described later, an example in which the shape of the base is a rectangular parallelepiped is shown, but the shape of the base is not limited to this.

  Since the base body 101 is integrally formed, there is no risk of fluid leaking from portions other than the connecting portions 106 to 108 with the external space, and the pressure resistance performance is high.

  In the outflow space Sa, the porous body 105 connects all of the other openings 102b, 102b,..., 103b, 103b,. It is arranged on the route. That is, when the porous body 105 causes the fluid to flow out from the other openings 102b, 102b,..., 103b, 103b,. All fluids are arranged to pass through.

  As a material constituting the porous body 105, a material having excellent chemical resistance such as plastic, polypropylene, polyethylene, acrylic, polyvinyl chloride, glass fiber, or the like is desirable.

  When the thickness of the porous body 105 is less than the pore diameter of the micropores 102 and 103, the fluids that have flowed into the porous body 105 flow out to the outside before being sufficiently mixed with each other. The effect of using the material 105 is reduced. In addition, when the thickness of the porous body 105 exceeds 5000 [μm], the pressure loss becomes large, and the number of mixers that can be accommodated is small. Therefore, the thickness of the porous body 105 in the direction in which the fluid passes is preferably 50 [μm] or more and 5000 [μm] or less, and more preferably 100 [μm] or more and 1000 [μm] or less.

  By allowing the fluid subdivided via the micropores to pass through pores smaller than the micropores, mixing of the fluids can be promoted. Therefore, the average pore size of the porous body 105 is preferably smaller than the pore size of the fine pores, and more preferably 50% or less of the pore size of the fine pores. Moreover, since the pressure loss will become large if the average hole diameter of the porous body 105 is too small, it is desirable that it is 0.5 [μm] or more.

  The porous body 105 is preferably in contact with a region of the surface of the substrate where the other openings 102b and 103b of the micropores are provided. In such a configuration, the other openings 102b and 103b of the fine holes through which the fluid flows out and the porous body 105 are close to each other. Therefore, it is possible to move the fluid to the porous body 105 in a shorter time than when both are separated from each other, and the mixing of the fluids can be started earlier. Therefore, it is particularly effective for fluids that can be synthesized only by rapid mixing.

  In the outflow space Sc, it is desirable that the other openings 102b, 102b,... 103b, 103b,. In this case, since the porous body 105 is spaced apart from the base body 101, the base body 101 can be prevented from being damaged by being in contact with the porous body 105. Therefore, the mixing process of the two liquids when the processing amount is increased can be stably performed.

  The operation of the micromixer 100 when the fluid La and the fluid Lb are mixed to produce the fluid Lc using the micromixer 100 will be described.

  In this case, the fluids La and Lb are supplied to the inflow spaces Sa and Sb, respectively. The supplied fluid La is divided so as to flow into the plurality of fine holes 102, 102,..., And the divided fluid La flows out to the outflow space Sc via the fine holes 102. Further, the supplied fluid Lb is divided so as to flow into the plurality of fine holes 103, 103,..., And the divided fluid Lb flows into the outflow space Sc via the fine holes 103. .

  Since the fluids La and Lb that have passed through the micro holes 102, 102,..., 103, 103,... Are all divided in micron order, the laminar flow has a small Reynolds number and a uniform orientation. F1 is made. In a fluid in which a flow forms a laminar flow F1, diffusion due to elements other than molecular motion is unlikely to occur like turbulent flow, and thus such fluids tend not to be efficiently mixed.

  A porous body 105 is arranged in the outflow space Sc, and the divided fluids La and Lb flowing out from the other openings 102b, 102b,... 103b, 103b,. It flows into the porous body 105.

  FIG. 2 is a diagram schematically showing a part of the cross-section 105A of the porous body 105 shown in FIG. 1 and the fluid flowing into the porous body 105 and the flow of the fluid. Innumerable holes are present at random positions inside the porous body 105, and a path (space) connected by a plurality of holes serves as a fluid flow path. The flow path inside the porous body 105 has a complicated shape in which branching or merging is repeated at random, and the fluid flowing therethrough is configured such that the flow direction changes finely.

  Since the diameter of the hole which the porous body 105 has is smaller than each diameter of the fine holes 102, 102, ..., 103, 103, ..., the fluids La and Lb passing through these fine holes are further reduced. It is finely divided and flows into the porous body 105 with each converging in the radial direction of the hole H. In the porous body 105, the fluid La and the fluid Lb flow in the same flow path.

  Since the diameter of the hole H inside the porous body 105 is sufficiently smaller than the width of the micropores 102 and 103 forming the flow path of the fluid before flowing into the porous body 105, it flows into the hole H from the flow path. The fluids La and Lb that converge are converged in the radial direction of the hole H. On the contrary, since the width of the flow path that the porous body 105 has is sufficiently larger than the diameter of the hole H, the flow of the fluids La and Lb that are finely divided and flowed in is repeatedly expanded rapidly by the hole H. , Flow separation occurs in the sudden expansion portion, and a vortex is generated. As a result, it becomes easy to mix with each other.

  As described above, in the micromixer 100 according to the first embodiment, the porous body 105 is arranged in the space Sc from which the fluid flows out, and the other openings 102b, 102b,. , 103b,... Are configured to flow out to the external space after passing through the porous body 105. Innumerable holes H are present at random positions inside the porous body 105, and a path (space) connected by the plurality of holes H is a fluid flow path. The flow path inside the porous body 105 has a complicated shape in which branching or merging is repeated at random, and the fluid flowing therethrough is configured such that the flow direction changes finely.

  .., 103, 103,... Pass through the holes H and flow paths inside the porous body 105 having the above-described configuration, so that the fluids branch and merge. repeat. Furthermore, vortices are generated in each fluid due to flow separation. As a result, the effect of mixing by vortex is added to the effect of mixing by molecular diffusion, and a plurality of types of fluids are efficiently mixed with each other. Therefore, according to the first embodiment of the present invention, a micromixer capable of efficiently mixing a plurality of types of fluids can be provided.

[Modification 1]
Fig.3 (a) is a perspective view which shows typically the structural example of the porous body 115 which concerns on the modification 1 of 1st embodiment. The porous body 115 is made of glass fiber, acrylic fiber, cellulosic fiber, or the like. FIG. 3B is an enlarged view of a part 115A of the porous body 115 shown in FIG. As shown in FIG. 3 (b), as the porous body 115, it is possible to use a material in which elongated substances such as fibers are complicatedly arranged.

  A plurality of holes are also present at random positions inside the porous body 115 according to the modified example 1, and a path (space) connected by the plurality of holes serves as a fluid flow path. . The flow path inside the porous body 115 has a complicated shape in which branching or merging is repeated at random, and the fluid flowing therethrough is configured so that the flow direction changes finely.

  As each fluid passing through the micropores passes through the pores and flow paths inside the porous body 115 having such a configuration, each fluid repeats branching and merging, and vortices are generated in each fluid. As a result, the effect of mixing by vortex is added to the effect of mixing by molecular diffusion, and a plurality of types of fluids are efficiently mixed with each other. Therefore, according to the first modification of the first embodiment of the present invention, a micromixer capable of efficiently mixing a plurality of types of fluids can be provided.

[Modification 2]
FIG. 4 is a perspective view schematically showing a configuration example of the porous body 125 according to the second modification of the first embodiment. The porous body 125 is made of polypropylene, polyethylene, polyvinyl chloride, or the like. As shown in FIG. 4, as the porous body 125, a sponge-like soft object 125a provided with a plurality of holes 125b may be used.

  A plurality of holes are also present at random positions inside the porous body 125 according to the modified example 2, and a path (space) connected by the plurality of holes 125b serves as a fluid flow path. Yes. The flow path inside the porous body 125 has a complicated shape in which branching or merging is repeated at random, and the fluid flowing therethrough is configured such that the flow direction changes finely.

  As each fluid passing through the micropores passes through the pores and flow paths inside the porous body 125 having such a configuration, each fluid repeats branching and merging, and furthermore, vortices are generated in each fluid. As a result, the effect of mixing by vortex is added to the effect of mixing by molecular diffusion, and a plurality of types of fluids are efficiently mixed with each other. Therefore, according to the second modification of the first embodiment of the present invention, a micromixer capable of efficiently mixing a plurality of types of fluids can be provided.

[Modification 3]
FIG. 5A is a perspective view schematically showing a configuration example of a porous body 135 according to Modification 3 of the first embodiment. The porous body 135 is composed of a polymer film such as a polymer. FIG. 5B is an enlarged view of a part 135A of the porous body 135 shown in FIG. As shown in FIG. 5 (b), as the porous body 135, a structure in which a honeycomb structure 135a made of a polymer is regularly arranged can be used.

  A plurality of holes are also present at predetermined positions inside the porous body 135 according to the modified example 3, and a path (space) connected by the plurality of holes serves as a fluid flow path. . The flow path inside the porous body 115 has a complicated shape that repeats branching or merging, and the fluid flowing through the porous body 115 is configured such that the flow direction changes finely.

  As each fluid passing through the micropores passes through the pores and flow paths inside the porous body 135 having such a configuration, each fluid repeats branching and merging, and vortices are generated in each fluid. As a result, the effect of mixing by vortex is added to the effect of mixing by molecular diffusion, and a plurality of types of fluids are efficiently mixed with each other. Therefore, according to the third modification of the first embodiment of the present invention, a micromixer capable of efficiently mixing a plurality of types of fluids can be provided.

  The present invention can be widely applied to a technical field using a microchemical process such as mixing and reaction of a plurality of types of fluids performed in a minute space.

100 ... micromixer, 101 ... substrate, 102,103 ... micropore,
102a, 103a ... one opening, 102b, 103b ... the other opening,
104 ... Fluid control device, 105 ... Porous body,
105A: a part of the cross section of the porous body, 106, 107, 108 ... a connecting portion,
F1 ... laminar flow, F2 ... turbulent flow, H, H1-Hn ... holes,
La, Lb, Lc ... fluid, S1 ... first space, S2 ... second space,
Sa, Sb ... inflow space, Sc ... outflow space, V ... vortex.

Claims (4)

A substrate having a plurality of micropores that function as flow paths, and a porous body;
Of the micropores, all the micropores constituting one group and all the micropores constituting the other group each have one opening in different regions on the surface of the substrate, and Having the other opening in another region common to the surface of the substrate,
The other opening of all the micropores constituting the group and the other opening of all the micropores constituting the other group are covered with the porous body. Mixer.   2. The micromixer according to claim 1, wherein the porous body is in contact with the surface of the base in the other common area.   The other opening of all the micropores constituting the group and the other opening of all the micropores constituting the other group are spaced apart from the porous body. The micromixer according to claim 1 or 2.   4. The micromixer according to claim 1, wherein an average pore diameter of the porous body is smaller than a pore diameter of the micropores.

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