JP2009241001A - Micromixer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a micromixer having advantageously enhanced mixing efficiency even with a simple apparatus structure. <P>SOLUTION: The micromixer 1 is provided with a feed port 2 through which a liquid is supplied and a plurality of manifolds 4 arranged in the direction to divide the flow of the liquid supplied from the feed port 2 and having a plurality of holes 5 passing the liquid. The manifolds 4 are respectively separated and the axis line A of the hole 5 on one manifold 4 of the opposed manifolds 4 in the manifolds 4 is at a position apart from the axis line A of the hole 5 of another manifold 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a novel micromixer that enables mixing and stirring of a plurality of types of microfluids.

  In the production and production of chemical compounds, efforts are made every day to improve the chemical reaction reaction control, such as supply of chemical reaction samples, mixing, heat supply for reaction activation, heat removal, and efficient catalytic reaction. ing. Improved reaction control allows for improved production safety, reaction product yield, reaction product purity, and isolation of useful highly active intermediate products.

  Conventionally, a large reaction tank is generally used for a chemical reaction. In recent years, as a device for generating fine particles, a device for mixing a plurality of fluids in a micro flow channel connected to a plurality of solution supply pipes represented by a micromixer or the like has been studied. Research aimed at increasing the efficiency of chemical reactions using these devices and creating new compounds has attracted attention. This micromixer causes a chemical reaction by diffusion and mixing of a plurality of fluids in a narrow flow path having an inner diameter on the order of submicrometer to millimeter.

As a conventional technique related to the structure of a micromixer, for example, as described in Patent Document 1, a micromixer using a substrate in which a micro flow path is formed in a Y shape, or as described in Patent Document 2, A micromixer using a substrate having a T-shaped micro flow path is known.
JP 2006-205080 A JP 2006-7063 A

  In the micromixer in which these Y-shaped and T-shaped microchannels are formed, the flow is in a laminar flow state. Therefore, the solution supplied from the two supply ports becomes a two-layer flow in the microchannel, and the stirring / mixing of these two layers is governed by diffusion. Therefore, it is difficult to perform complete mixing in a short time. There is a problem that time is required.

  For the purpose of shortening the mixing time, as a means for increasing the area of the interface between the two liquids, for example, the flow of two layers is divided into a large number on a plane to form a large number of laminar flows. The method of improving stirring efficiency is mentioned. However, since such a method divides the flow into a large number, it is necessary to form a complicated multi-channel using a precision processing technique, which is not preferable because the processing cost increases. In addition, even when multi-channel is used, since it is a micro-channel formed in a plane, the fluid is still laminar and stirring / mixing is governed by diffusion. There was room for improvement. In addition, in order to form a multi-channel on a plane, a large substrate area is required to some extent, which has a problem that it cannot be used for the purpose of downsizing the entire micromixer.

Furthermore, other micromixer conventional technologies include a mixer using a porous filter, a multilayer mixer, a mixer that performs mixing by chaotic mixing using a spiral flow of fluid, and a pseudo turbulent flow generated by colliding with a flow path wall. A wide variety of micromixers have been reported, such as mixers using ultrasonic waves, ultrasonic waves, electric fields, magnetic fields, and micromixers using micro stirrers (for example, Patent Document 3). Since the road pattern and the device configuration are complicated, there is a problem that it is expensive and not suitable for mass production.
JP 2006-320877 A

  The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide a micromixer that can advantageously increase the mixing efficiency while having a simple device configuration.

  In order to achieve the above object, a micromixer according to the present invention includes a supply port to which a fluid is supplied, and a plurality of holes that are arranged in a direction to divide the flow of the fluid supplied from the supply port and have a plurality of holes through which the fluid passes. The flow dividing plates are separated from each other, and the axis of the hole in one of the flow dividing plates of the flow dividing plates facing each other is located away from the axis of the hole in the other flow dividing plate. It is characterized by that. The term “fluid” as used herein refers to an object that can be handled as a liquid or gas, and the term “fluid flow” refers to the direction in which the fluid supplied into the micromixer flows from the supply port to the discharge port. It shall be said.

  Moreover, in each flow dividing plate, it is preferable that the holes are spaced apart at equal intervals.

  Furthermore, it is preferable to provide the holes of the other flow dividing plate at a position inclined in the range of 15 to 40 ° with respect to the axis of the hole of the one flow dividing plate.

  Furthermore, it is preferable that the aperture diameter of the flow dividing plate is in the range of 0.05 to 3.00 mm.

  In addition, it is preferable to connect a plurality of the above-described micromixers of the present invention.

  According to the present invention, it is possible to provide a micromixer capable of remarkably increasing the mixing efficiency while having a simple device configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view of a typical micromixer according to the present invention. 2A is a perspective view of the flow dividing plate of the micromixer shown in FIG. 1, FIG. 2B is a top view of the flow dividing plate, and FIG. 2C is a hole of the flow dividing plate. It is a conceptual diagram which shows the behavior of the fluid when a fluid passes through. FIG. 3 is a partially enlarged view showing a flow dividing plate of the micromixer according to the present invention. FIG. 4 is a conceptual diagram showing the behavior of the fluid flowing between the flow dividing plates when the fluid is passed through the micromixer according to the present invention. FIG. 5 is a side sectional view of another micromixer according to the present invention. 6A is a perspective view of the flow dividing plate of the micromixer shown in FIG. 5, and FIG. 6B is a top view of two facing flow dividing plates among the flow dividing plates. FIG. 7 is a side sectional view of another micromixer according to the present invention.

As shown in FIG. 1, the micromixer 1 according to the present invention has two supply ports 2 that supply different fluids and a discharge port 3 that discharges the fluid mixed in the micromixer 1. In addition, two flow dividing plates 4 are attached in an arrangement in which the flow of the fluid supplied from each supply port 2 is divided. The flow dividing plate 4 is provided with holes 5 for promoting mixing of the fluid, and the flow dividing plate 4 on the side where the fluid first passes, that is, the upstream flow dividing plate 4 is provided with four holes 5 in the illustrated example. In the illustrated example, five holes 5 are provided in the flow dividing plate 4 on the side through which the fluid passes next, that is, on the downstream side. 2A and 2B, the axis A of the hole 5 (shown by a solid line in the drawing) of the upstream flow dividing plate 4 and the hole 5 of the downstream flow dividing plate 4 (shown in FIG. 2). Axis A (indicated by a dotted line in the figure) is at a position separated from each other and does not overlap each other.
When such a configuration is adopted and the holes 5 are provided in the flow dividing plate 4, the flow path becomes narrow at the holes 5, so that when the fluid passes through the holes 5, the fluid is focused and the fluid pressure increases. Then, the fluid passing through the hole 5 accelerates. Specifically, according to Bernoulli's theorem, the fluid passing through the periphery accelerates rather than the fluid passing through the axis of the hole 5. Since the speed of the fluid flowing in the direction inclined from the axis A of the hole 5 is larger than the speed of the fluid flowing along the axis A of the hole 5 on the downstream side of the hole 5, on the downstream side of the hole 5, The behavior of the fluid as shown in FIG. 2C (indicated by an arrow X in the figure) is generated, and turbulent flow is generated.
As a result, compared with the case where fluids are mixed without generating turbulent flow through the holes 5, fluid mixing is promoted, and fluid mixing efficiency can be improved. Further, as described above, on the downstream side of the hole 5, the speed of the fluid flowing in the direction inclined from the axis A of the hole 5 is larger than the speed of the fluid flowing along the axis A of the hole 5, Corresponding to the speed difference, the axis A of the hole 5 of the upstream flow dividing plate 4 and the axis A of the hole 5 of the downstream flow dividing plate 4 are shifted to be ejected from the hole 5 and mixed by turbulent flow. Thus, the fluid in a state of being smoothly flows into the holes 5 of the downstream flow dividing plate 4, which facilitates fluid mixing and improves fluid mixing efficiency.

In addition, as shown in FIG. 3, in the opposing flow dividing plate 4, the downstream flow dividing plate 4 is located at a position inclined within a range of 15 to 40 ° with respect to the axis A of the hole 5 of the upstream flow dividing plate 4. These holes 5 are preferably provided. When the inventor flows the fluid through the hole 5, the turbulent flow generated on the downstream side of the hole 5 becomes the behavior X of the fluid including the vortex structure as shown in FIG. It has been found that it becomes particularly large in the range of 15 to 40 ° with respect to the axis A of the hole 5 of the upstream flow dividing plate 4. Accordingly, by correspondingly providing the hole 5 of the downstream flow dividing plate 4 at a position inclined in the range of 15 to 40 ° with respect to the axis A of the hole 5 of the upstream flow dividing plate 4. The fluid mixed by the turbulent flow with the vortex structure flows smoothly, the fluid mixing is promoted, and the fluid mixing efficiency may be further improved. Further, among the holes 5 provided in the upstream flow dividing plate 4, the fluids flowing from the adjacent holes 5 are the holes 5 of the downstream flow dividing plate 4, and the angle ranges with respect to both the holes 5. Therefore, there is a possibility that the fluid mixing is promoted and the fluid mixing efficiency is further improved.
Depending on the type of fluid to be mixed and the desired mixing efficiency, the number of flow dividing plates 4 attached to the micromixer 1 can be increased, or the number of holes 5 can be increased or decreased. Like the micromixer 1 shown in FIGS. 5-6, it can be set as the structure which arranged the eight shunt plates 4 with the number of the holes 5 12 and 13 alternately. Examples of combinations of fluids used for mixing include, for example, a combination of gases such as hydrogen and carbon dioxide, a combination of aqueous solutions of sodium hydroxide and hydrochloric acid, and enzymatic reactions (decomposition reactions) such as aqueous starch and amylase. And a combination of liquids for inducing).

  Furthermore, in each flow dividing plate 4, it is preferable that the holes 5 are spaced apart at equal intervals. This is because the turbulent flow generated for each hole 5 on the downstream side of the hole 5 becomes a shape similar to the whole by separating the holes 5 at equal intervals in each flow dividing plate 4. This is because the fluid passing therethrough has the same fluid behavior as a whole, and the fluid is mixed to the same extent on the downstream side of each hole 5, so that the fluid is mixed homogeneously as a whole.

  Furthermore, the diameter W1 of the hole 5 of the flow dividing plate 4 is preferably in the range of 0.05 to 3.00 mm. When the diameter W1 of the hole 5 of the flow dividing plate 4 is less than 0.05 mm, the diameter W1 becomes too small. Therefore, depending on the type and density of the fluid, a sufficient flow rate through the hole 5 per unit time cannot be ensured. . Therefore, the fluid does not sufficiently flow downstream of the hole 5 and turbulent flow cannot be sufficiently generated. Therefore, the mixing of the fluid is not effectively promoted, and the mixing efficiency of the fluid may not be improved. There is. Moreover, it is considerably difficult to provide the holes 5 having a diameter W1 of less than 0.05 mm in the flow dividing plate 4, the manufacturing cost becomes high, and the mass production is not suitable. On the other hand, when the diameter W1 of the hole 5 of the flow dividing plate 4 exceeds 3.00 mm, the diameter W1 becomes too large, so that when the fluid passes through the hole 5, the fluid is not sufficiently focused and accelerated, Since the turbulent flow is not sufficiently generated, the mixing of the fluid is not effectively promoted, and the mixing efficiency of the fluid may not be improved.

  In addition, it is preferable to connect a plurality of the above-described micromixers 1 of the present invention. This is because by connecting a plurality of micromixers 1 of the present invention and repeating fluid mixing a plurality of times, a more mixed fluid can be obtained. Alternatively, after different fluids are mixed for each micromixer 1, the mixed fluids can be further mixed using the micromixer 1.

  The above description shows only a part of the embodiment of the present invention, and these configurations can be combined alternately or various changes can be made without departing from the gist of the present invention. For example, the shape of the hole 5 of the flow dividing plate 4 shown in the drawing as viewed from above is circular, but the shape of the hole 5 is not limited to this, and may be any shape such as an ellipse or a rectangle. . Moreover, although the micromixer 1 in the illustrated example has two supply ports 2, the number of the supply ports 2 can be arbitrarily set. For example, as shown in FIG. Thus, it is possible to mix three kinds of fluids simultaneously. Further, in the illustrated example, the neck portion 6 is shaped so that the flow path gradually narrows before the fluid reaches the flow dividing plate 4, but whether or not the neck portion 6 is provided is an arbitrary selection. . When the neck portion 6 is provided, the fluid gradually converges and accelerates along the direction in which the fluid flows, and a turbulent flow is generated after the passage, so that the fluid is mixed to some extent before reaching the flow dividing plate 4. Thus, the fluid mixing is promoted, and the fluid mixing efficiency is further improved.

  Next, a micromixer according to the present invention (example micromixer) and a conventional micromixer (conventional example micromixer) were prototyped and their performance was evaluated for comparison, and will be described below.

  As shown in FIG. 5, the embodiment micromixer 1 has two supply ports 2 for supplying fluid and one discharge port 3, and a flow dividing plate 4 provided with twelve or thirteen holes 5. 8 are attached alternately. The diameters of the holes 5 are all 0.3 mm, and in the opposing flow dividing plate 4, the arrangement of the holes 5 is a downstream flow dividing plate at a position inclined by 18 ° with respect to the axis A of the hole 5 of the upstream flow dividing plate 4. The arrangement is such that there are four holes 5. Moreover, the mixed fluid from the discharge port 3 was configured to directly flow into the ultraviolet-visible spectrophotometer.

  As shown in FIG. 8, the prior art micromixer 201 is provided with a first tubular member 202 and a second tubular member 203 facing each other, a first fluid 7 passing through the first tubular member 202, and a second tubular member. After the second fluid 8 passing through 203 is collided with the second fluid 8 to form a mixed fluid, the mixed fluid 9 is discharged through the third tubular member 206. Both the first tubular member 202 and the second tubular member 203 have a length of 35 mm, an outer diameter of 1.6 mm, and an inner diameter of 0.48 mm, and the third tubular member 206 has a length of 50 mm and an outer diameter of 1.6 mm. The inner diameter was 0.48 mm. In addition, similar to the example micromixer, the mixed fluid from the discharge port was configured to directly flow into the ultraviolet-visible spectrophotometer.

Using these microphone mixers, the mixing characteristics of two types of fluids were evaluated. The two fluids mixed were KI: KIO ₃ : H ₃ BO ₃ : 2% sulfuric acid aqueous solution (fluid A), 1.60% KI aqueous solution, 0.41% KIO ₃ aqueous solution, 3.34% H ₃ BO ₃ aqueous solution and 0.80% NaOH aqueous solution are mixed at a ratio of 1: 1: 1: 1 by volume ratio, which is a four-type mixed aqueous solution (fluid B). These fluids were supplied at a flow rate of 0.50 to 8.75 mL / min from the respective supply ports of the example micromixer and the conventional micromixer. Then, the mixing characteristics of fluid A and fluid B were evaluated using the Villermuux / Dushman reaction. That is, when two types of fluids are mixed, a fast reaction is preferentially advanced when the mixing characteristics are good, and conversely, a slow reaction is also advanced when the mixing characteristics are poor. The mixing characteristics can be evaluated by measuring the concentration of the substance. Specifically, when mixing the fluids A and B, acid - alkali neutralization reaction or mixing characteristic reactions occur at a I ₂ formation reaction worse case, if this I ₂ formation reaction occurred, generating The I ₂ partly becomes I ₃ ⁻ , but this I ₃ ⁻ has an absorption peak at a wavelength of 353 nm, and thus its absorbance was measured to evaluate the mixing characteristics. In addition, it has shown that the mixing characteristic is excellent, so that the absorption peak in the wavelength of 353 nm is small. The evaluation results are summarized in a graph and shown in FIG.

  As is apparent from the results of FIG. 9, the example micromixer had a small absorption peak at a wavelength of 353 nm and excellent mixing characteristics at any flow rate compared to the conventional micromixer.

  As apparent from the above, according to the present invention, it is possible to provide a micromixer capable of remarkably increasing the mixing efficiency while having a simple device configuration.

1 is a side sectional view of a typical micromixer according to the present invention. (A) is a perspective view of the flow dividing plate of the micromixer shown in FIG. 1, (b) is a top view of the flow dividing plate, and (c) is a view when a fluid passes through the holes of the flow dividing plate. It is a conceptual diagram which shows the behavior of a fluid. It is the elements on larger scale of the micromixer according to this invention. It is a conceptual diagram which shows the behavior of the fluid when a fluid is passed through the micromixer according to the present invention. It is side sectional drawing of the other micromixer according to this invention. (A) is a perspective view of the flow dividing plate of the micromixer shown in FIG. 5, and (b) is a top view of two opposed flow dividing plates among such flow dividing plates. It is side sectional drawing of the other micromixer according to this invention. It is a conceptual diagram explaining a prior art micromixer. It is a graph which shows the evaluation result which measured the light absorbency in the wavelength of 353 nm with respect to the flow rate of mixed fluid about an example micromixer and a conventional example micromixer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Micromixer 2 Supply port 3 Discharge port 4 Dividing plate 5 Hole 6 Neck part A Axis line X of a diverting plate Fluid behavior W1 Diameter of the hole of a diverting plate W2 Thickness of a diverting plate

Claims (5)

  A supply port to which a fluid is supplied; and a plurality of flow dividing plates which are arranged in a direction to divide the flow of the fluid supplied from the supply port and have a plurality of holes through which the fluid passes. A micromixer characterized in that an axis of a hole in one of the flow-dividing plates of the flow-dividing plates facing each other is located away from an axis of the hole in the other flow-dividing plate.   The micromixer according to claim 1, wherein the holes are spaced apart at equal intervals in each of the flow dividing plates.   The hole of the other flow dividing plate is provided in the position which inclines in the range of 15-40 degrees with respect to the axis line of the hole of one flow dividing plate in the said opposing flow dividing plate. Micromixer.   4. The micromixer according to claim 1, wherein a diameter of the hole is in a range of 0.05 to 3.00 mm.   A micromixer formed by connecting a plurality of the micromixers according to claim 1.

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