JP2004330008A - Micro-channel apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a micro-channel apparatus in which a fine particle in a suspension can be classified/separated surely even when a very small amount of the suspension is supplied to this apparatus. <P>SOLUTION: This micro-channel apparatus is provided with an inlet port 16 for taking the suspension in this apparatus, a curved flow passage 13 one end of which is fit to the port 16, a plurality of branched flow passages 14, 15 each of which is fit to the downstream side of the passage 13 and a plurality of outlet ports 17, 18 each of which is fit to one end of any of the passages 14, 15 for discharging the suspension after made to pass through the passages 13, 14, 15. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a microchannel device used for classification / separation of fine particles contained in a suspension.
[0002]
[Prior art]
With the advancement of nano / micro technology, micro devices such as micro reactors and micro chemical plants are attracting attention. This apparatus is used for producing a suspension containing fine particles (solid fine particles, emulsion, etc.), and is characterized in that the amount of the generated fine particles is very small. This device is referred to as a “granulation device” in the following description. In the case of a fine granulation apparatus, the suspension is "generated in a very small amount" by utilizing the speed of movement of a substance or heat.
[0003]
In addition, in order to take out the fine particles in the suspension generated by the above-mentioned fine granulator as a product, classification (separating the same type by size) and separation (separating different types and sizes) are necessary. Separation) is required, and it is desired that the apparatus for performing such an operation be of a micro size as in the case of the granulating apparatus.
Therefore, miniaturization of a cyclone of an existing device has been studied (for example, see Patent Document 1). This small cyclone has a diameter of 10 mm, and classifies and separates fine particles by using a large centrifugal force generated in the apparatus.
[0004]
[Patent Document 1]
Cillers, J.M. J. And S. T. L. Harrison, "The Applications of mini-hydrocyclones in the concentration of last suspensions", The Chemical Engineering Journal, 1997, 2621-26.
[0005]
[Problems to be solved by the invention]
However, in the above-mentioned conventional small cyclone, a large flow rate (for example, 150 l / h) was required to generate a large centrifugal force in the apparatus. That is, a large amount of suspension sample was required. For this reason, if the supply amount of the suspension sample to the small cyclone is small, sufficient centrifugal force cannot be generated, and as a result, sufficient classification and separation effects cannot be obtained.
[0006]
In order to increase the classification / separation effect of a small cyclone, a large amount of suspension must be generated by operating a minute granulator (microreactor, etc.) for a long time. It cannot take advantage of the characteristic of “generation”.
An object of the present invention is to provide a microchannel device capable of reliably classifying and separating fine particles in a suspension even when the supply amount of the suspension is very small.
[0007]
[Means for Solving the Problems]
The microchannel device according to claim 1, wherein the inlet port takes in the suspension, a curved flow path having one end attached to the inlet port, and a plurality of branched flows attached downstream of the flow path. And a plurality of outlet ports attached to one end of the branch flow path on the downstream side and configured to discharge the suspension having passed through the curved flow path and the branch flow path.
[0008]
According to a second aspect of the present invention, in the microchannel device according to the first aspect, the curved flow path is constituted by a part of a circular shape.
According to a third aspect of the present invention, in the microchannel device according to the second aspect, the curved flow path has a sectional area of A, a radius of curvature of R, and a flow rate of the suspension taken into the inlet port. Is Q, the following conditional expression is satisfied.
[0009]
(Q / A) ² /R>9.8
According to a fourth aspect of the present invention, in the microchannel device according to any one of the first to third aspects, the curved flow path has a Dean vortex in the suspension flowing downstream. It has a length that can occur.
According to a fifth aspect of the present invention, in the microchannel device according to any one of the first to fourth aspects, the inlet port, the curved flow path, the plurality of branch flow paths, and the plurality of branch flow paths are provided. A plurality of units each including an outlet port are provided, and the plurality of units are connected in parallel with each other.
[0010]
According to a sixth aspect of the present invention, in the microchannel device according to any one of the first to fourth aspects, the inlet port, the curved flow path, the plurality of branch flow paths, and the plurality of branch flow paths are provided. A plurality of units each including an outlet port are provided, and the plurality of units are connected in series to each other.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0012]
As shown in FIGS. 1 to 6, the microchannel device 10 of the present embodiment includes a microscale channel (13 to 15) provided between two acrylic plates 11 and 12 and a channel (13). 15), one inlet port 16 attached to the upstream side, and two outlet ports 17, 18 attached to the downstream side.
FIG. 1 is a diagram of the microchannel device 10 as viewed from above. 2 and 3 are enlarged views of the dotted frames 10A and 10B of FIG. 4 and 5 are AA cross section and BB cross section of FIG. FIG. 6 is a schematic diagram illustrating a usage pattern of the microchannel device 10.
[0013]
The acrylic plates 11 and 12 are sealed by a stainless bolt nut 22 of, for example, M8 through a plurality of through holes 21 (FIG. 5). The size of the acrylic plates 11 and 12 is, for example, 10 cm on one side. The thickness of the acrylic plate 11 is, for example, 2 cm. The thickness of the acrylic plate 12 is, for example, 1 cm. Note that the acrylic plates 11 and 12 may be sealed by a sealing method using adhesion or joining (fusing) in addition to fastening with the bolts and nuts 22.
[0014]
The channels (13 to 15) are obtained by cutting the surface of the acrylic plate 11 using a straight end mill (for example, a diameter of 200 μm). The cross section of the flow path (13 to 15) is rectangular (FIGS. 4 and 5). The channels (13 to 15) may be formed by an etching method or laser micromachining, in addition to a mechanical cutting method using a straight end mill.
[0015]
In addition, the flow path (13 to 15) has an arc shape on the upstream side and is branched into two on the downstream side. In the following description, the arc-shaped portion 13 on the upstream side is “arc-shaped channel 13”, the straight portion 14 after branching inward on the downstream side is “inner branch channel 14”, and the branch is outward on the downstream side. The later straight portion 15 is referred to as “outside branch channel 15”. The inside corresponds to the center of curvature, and the outside corresponds to the side opposite to the center of curvature.
[0016]
The arc-shaped channel 13 is a semicircular channel having a radius of curvature of about 2 cm. The cross section of the arc-shaped channel 13 has a width C of about 200 μm and a depth D of about 170 μm shown in FIG. An inlet port 16 is attached to one end on the upstream side of the arc-shaped channel 13 (FIGS. 1 and 5).
The inner branch channel 14 has the same cross-sectional width and depth as the arc-shaped channel 13. An outlet port 17 is attached to one end on the downstream side of the inner branch flow path 14 (FIGS. 1 and 5).
[0017]
The outer branch channel 15 has a cross-sectional width twice as large as the arc-shaped channel 13 and the inner branch channel 14 on the downstream side (FIG. 3). The depth of the outer branch channel 15 is the same as the arc-shaped channel 13 and the inner branch channel 14. An outlet port 18 is provided at one end on the downstream side of the outer branch channel 15 (FIGS. 1 and 5).
The inlet port 16 is a through hole (for example, 5.5 mm in diameter) provided in the acrylic plate 11. A tube 34 (for example, a diameter of 4 mm) is attached to the inlet port 16 via a connector 31 fitted to the back side of the acrylic plate 11 with a screw, and a micro feeder 37 is attached to the tube 34. After passing through the tube 34, the suspension in the micro feeder 37 is taken into the inside from the inlet port 16.
[0018]
The outlet port 17 is a through hole (for example, 5.5 mm in diameter) provided in the acrylic plate 11. A tube 35 (e.g., 4 mm in diameter) is attached to the outlet port 17 via a connector 32 fitted on the back side of the acrylic plate 11 with a screw. The tip of the tube 35 is contained in a sample bottle 38.
Similarly, the outlet port 18 is a through hole (for example, 5.5 mm in diameter) provided in the acrylic plate 11. A tube 36 (e.g., 4 mm in diameter) is attached to the outlet port 18 via a connector 33 fitted on the back side of the acrylic plate 11 with a screw. The tip of the tube 36 is in a sample bottle 39.
[0019]
In the microchannel device 10 having the above-described configuration, the suspension taken into the inside from the inlet port 16 passes through the arc-shaped channel 13, and then advances to the inner branch channel 14 and the outer branch channel 15. Incidentally, the suspension passing through the inside of the arc-shaped flow path 13 flows into the inner branch flow path 14, and the suspension passing through the outside flows into the outer branch flow path 15.
[0020]
In the microchannel device 10 of the present embodiment, as shown in FIG. 3, the cross-sectional width of the outer branch flow path 15 is twice the width of the inner branch flow path 14 on the downstream side, and the cross-sectional area of the outer branch flow path 15 is reduced. It was twice as large as the inner branch flow path 14. For this reason, the flow rate of the suspension flowing into the outer branch flow path 15 can be about twice the flow rate of the suspension flowing into the inner branch flow path 14.
[0021]
In this case, as shown in FIG. 7, at the most downstream point of the arc-shaped flow path 13 (a branch point to the inner branch flow path 14 and the outer branch flow path 15), about one-third of the inner area of the cross section is reduced. The suspension in the occupied area E flows into the inner branch flow path 14, and the suspension in the area F occupying about ／ of the outer area flows into the outer branch flow path 15.
[0022]
Then, the suspension after passing through the inner branch flow path 14 is discharged from the outlet port 17 and flows into the inner sample bottle 38 via the tube 35. The suspension after passing through the outer branch channel 15 is discharged from the outlet port 18 and flows into the outer sample bottle 39 via the tube 36.
Next, an operation of classifying and separating fine particles in the suspension by the microchannel device 10 of the present embodiment will be described with reference to FIGS. Here, the description will be made on the assumption that two kinds of fine particles having different sizes are contained in the suspension. The fine particles are solid fine particles, emulsions (droplets), animal cells, plant cells, erythrocytes, and the like.
[0023]
The suspension taken in from the inlet port 16 has not yet received a centrifugal force at the most upstream point of the arc-shaped channel 13. Therefore, as shown in FIG. 8A, two kinds of fine particles 25 and 26 having different sizes are uniformly distributed in the cross section.
Thereafter, these fine particles 25 and 26 receive a radially outward centrifugal force F1 while flowing in the circumferential direction along the arc-shaped flow path 13, and as shown in FIG. I approach the side 3A. Here, since the arc-shaped flow path 13 has a small cross-sectional area, the flow velocity of the fine particles 25 and 26 becomes very large even with a very small flow (very small flow rate). Further, since the radius of curvature of the arc-shaped channel 13 is small, a very large centrifugal force F1 is generated.
[0024]
For example, when the suspension is fed at a rate of 6 ml / min into the arc-shaped channel 13 having one side (C and D in FIG. 7) of 200 μm, the average cross-sectional velocity in the arc-shaped channel 13 is 2. 5 m / s. Further, when the radius of curvature of the arc-shaped channel 13 is 2 cm, the centrifugal force F1 is 312.5 m / s. ² It becomes. The Reynolds number is about 500 (that is, a laminar flow state).
As described above, a very large centrifugal force F1 is generated in the cross section of the arc-shaped flow path 13, and the two types of fine particles 25 and 26 both move toward the outer side surface 3A, but in the cross section downstream from a certain point, As shown in FIG. 8C, a secondary flow caused by the centrifugal force F1, that is, Dean vortices F2 and F3 develops. The Dean vortices F2 and F3 are a pair of flow fields that develop up and down in the cross section.
[0025]
One of the upper sides (F2) of the Dean vortices F2 and F3 flows radially outward in the middle of the arc-shaped channel 13 and becomes upward in the vicinity of the outer surface 3A, and radially in the vicinity of the upper wall 3C. Flows inward, and becomes downward in the vicinity of the inner side surface 3B. That is, it circulates in the upper half of the cross section of the arc-shaped channel 13.
Similarly, one of the lower sides (F3) of the Dean vortices F2 and F3 flows radially outward in the middle of the arc-shaped flow path 13 and becomes downward in the vicinity of the outer surface 3A. It flows radially inward near and becomes upward near the inner surface 3B. That is, it circulates in the lower half of the cross section of the arc-shaped channel 13.
[0026]
When the Dean vortices F2 and F3 develop in the cross section of the arc-shaped channel 13, the following phenomenon occurs due to the balance between the strength of the Dean vortices F2 and F3 and the centrifugal force F1. In other words, the small particles 25 that are easy to ride on the flow circulate in the cross section together with the Dean vortices F2 and F3, and the large particles 26 remain unevenly near the outer surface 3A without riding on the flow. As a result, the concentration of the large particles 26 increases outside the cross section of the arc-shaped channel 13, and the concentration of the small particles 25 increases inside the arc-shaped channel 13.
[0027]
For this reason, the suspension reaching the most downstream point (branch point to the inner branch flow path 14 and the outer branch flow path 15) of the arc-shaped flow path 13 in the same distribution state as in FIG. The inner part (suspension in the region E in FIG. 7) containing a large amount of 25 flows into the inner branch flow path 14, and the outer part (the suspension in the region F in FIG. 7) containing a large amount of large fine particles 26 is formed. It will flow into the outer branch channel 15.
[0028]
Then, the suspension (many small particles 25) after passing through the inner branch channel 14 is discharged from the outlet port 17 and flows into the inner sample bottle 38 via the tube 35. Further, the suspension after passing through the outer branch channel 15 (there are many large fine particles 26) is discharged from the outlet port 18 and flows into the outer sample bottle 39 via the tube 36.
[0029]
Therefore, according to the microchannel device 10 of the present embodiment, even at an extremely small flow rate (for example, 6 ml / min), the fine particles in the suspension can be reliably classified and separated. When the two types of fine particles 25 and 26 are of the same type, it means that a classification operation as shown in FIG. 9 has been performed. If the two types of particles 25 and 26 are different, it means that a separation operation as shown in FIG. 10 has been performed.
[0030]
Next, a specific experimental example (FIGS. 11 and 12) of a classification operation by the microchannel device 10 of the present embodiment will be described.
Here, a sample (0.06 wt%) in which acrylic particles (trade name: MR-10HG manufactured by Soken Chemical Co., Ltd.) having a specific gravity of 1.19 and a mode particle size (mode particle size) of 9 μm were suspended in ion-exchanged water. This suspension was supplied from the micro feeder 37 to the inlet port 16 in a Reynolds (Re) number range of 150 to 600. The diameter of the fine particles contained in the suspension is widely distributed in the range of about 1 μm to 60 μm (polydispersed system).
[0031]
Then, for the suspensions flowing into the sample bottles 38 and 39 from the outlet ports 17 and 18 of the microchannel device 10, the particle size distribution of fine particles (SALD-200 VER Model-2 manufactured by Shimadzu Corporation) was measured. For example, the measurement result when the Re number is 600 is as shown in FIG. FIG. 11 shows a volume-based particle size distribution.
The particle size distribution of the fine particles of the suspension flowing into the inner sample bottle 38 is shown by the solid line in FIG. _IN Is about 7.5 μm. The particle size distribution of the fine particles of the suspension that has flowed into the outer sample bottle 39 is, as shown by the dotted line in FIG. _OUT Is about 13.4 μm.
[0032]
In other words, small particles (D _IN = 7.5 μm) and large fine particles (D _OUT = 13.4 μm). From the measurement results in FIG. 11, a clear classification effect by the microchannel device 10 of the present embodiment has been demonstrated.
[0033]
Further, the mode particle diameter D in the outer sample bottle 39 _OUT And the mode diameter D in the inner sample bottle 38 _IN (= Mode particle size ratio D _OUT / D _IN ) Was calculated and plotted in FIG. The horizontal axis in FIG. 12 is the Re number. “◇” in FIG. 12 indicates the mode particle size ratio D _OUT / D _IN Shows the dependence on the Re number.
From the measurement result of “◇” in FIG. _OUT / D _IN Shows the same value (1.3 to 1.8) regardless of the change in the Re number. This is the outermost mode particle size D _OUT Is the mode diameter D inside _IN This is about 1.3 to 1.8 times that of the above, indicating a clear classification effect of the microchannel device 10. By the way, the most frequent particle size ratio D _OUT / D _IN Is "1", it means that the most frequent particle size is equal in the inner and outer sample bottles 38 and 39, and no classification is performed.
[0034]
As described above, according to the microchannel device 10 of the present embodiment, a clear classification effect can always be obtained with an extremely small flow rate even when the Re number is changed (range 150 to 600) (FIGS. 11 and 10). 12 ◇).
The mass of each of the suspensions flowing into the inner and outer sample bottles 38 and 39 was measured. By measuring the mass of the suspension in the inner sample bottle 38, the flow rate Q at the inner outlet port 17 is determined. _IN Can be requested. Similarly, by measuring the mass of the suspension in the outer sample bottle 39, the flow rate Q at the outer outlet port 18 is determined. _OUT Can be requested.
[0035]
And the flow rate Q at the outer outlet port 18 _OUT And the flow rate Q at the inner outlet port 17 _IN (= Flow ratio Q _OUT / Q _IN ) Was calculated and plotted with “○” in FIG. "O" in FIG. 12 indicates the flow ratio Q _OUT / Q _IN Shows the dependence on the Re number. From this measurement result, the flow ratio Q _OUT / Q _IN Shows the same value (2.0 to 2.5).
[0036]
Further, the absorbance (APEL, PD-303) at a wavelength of 900 nm was measured for each of the suspensions flowing into the inner and outer sample bottles 38, 39. By measuring the absorbance, the concentration of each suspension can be determined. Incidentally, the absorbance is almost proportional to the concentration.
[0037]
And the absorbance I in the outer sample bottle 39 _OUT And the absorbance I in the inner sample bottle 38 _IN (= Absorbance ratio I _OUT / I _IN ) Was calculated and plotted with “□” in FIG. “□” in FIG. 12 indicates the absorbance ratio I _OUT / I _IN Shows the dependence on the Re number. From this measurement result, the absorbance ratio I was obtained regardless of the change in the Re number. _OUT / I _IN Shows the same value (1.5 to 2.0).
[0038]
The measurement results of “O” and “□” in FIG. 12 are due to the fact that the width of the cross section of the outer branch flow path 15 is twice as large as that of the inner branch flow path 14 as already described with reference to FIG. . That is, since the width of the cross section of the outer branch channel 15 is twice, the flow rate Q from the outer sample bottle 39 is smaller than that of the inner sample bottle 38. _OUT Was 2.0 to 2.5 times, and a suspension having a concentration of 1.5 to 2.0 times could be obtained.
[0039]
In this case, the amount of fine particles flowing into the outer sample bottle 39 (= flow rate Q _OUT (2.0 to 2.5 times) × concentration (1.5 to 2.0 times)) is about 3.0 to 4.5 times the amount of the fine particles flowing into the inner sample bottle 38. That is, a large amount of fine particles can be obtained from the outside compared to the inside.
Note that the same measurement results as those in FIGS. 11 and 12 described above could be obtained with a suspension containing acrylic particles having a mode particle size of 7 μm and a suspension containing acrylic particles having a mode particle size of 20 μm.
[0040]
As described above, according to the microchannel device 10 of the present embodiment, even if the supply amount of the suspension from the inlet port 16 is extremely small, the particles in the suspension can be reliably classified and separated. Can be.
However, the cross-sectional area of the arc-shaped channel 15 is A [m ² ], The radius of curvature is R [m], and the flow rate of the suspension taken into the inlet port 16 is Q [m ³ / S], it is preferable to satisfy the following conditional expression (1). When conditional expression (1) is satisfied, at least a centrifugal force equal to or higher than gravity can be generated, so that the fine particles in the suspension can be classified and separated.
[0041]
(Q / A) ² /R>9.8 (1)
Furthermore, according to the microchannel device 10 of the present embodiment, the flow path (arc-shaped flow path 13) for generating the centrifugal force F1 and the Dean vortex F2, F3 in the suspension is constituted by a part of a circular shape. (13) can be shortened, and can be classified and separated efficiently.
[0042]
Further, according to the microchannel device 10 of the present embodiment, the classification and separation accuracy of the fine particles in the suspension can be adjusted according to the flow rate of the suspension sent from the microfeeder 37. Further, when the diameter of the fine particles is different, it can be dealt with by the flow rate from the micro feeder 37. That is, by adjusting the flow rate according to the diameter of the fine particles, classification / separation can be performed with constant accuracy regardless of the diameter of the fine particles.
[0043]
Further, according to the microchannel device 10 of the present embodiment, the flow rate from the microfeeder 37 is adjusted so that the Dean vortices F2 and F3 are not generated in the cross section of the arc-shaped channel 13 (or the Dean vortex F2). By weakening F3), the fine particles in the suspension can be concentrated as shown in FIG. 13 (Concentration). In this case, a thick suspension can be obtained from the outer sample bottle 39 via the outer branch channel 15 and the outlet port 18.
[0044]
Further, as shown in FIG. 14, the microchannel device 10 of the present embodiment can be directly connected to a downstream portion of a minute granulation device 40 such as a microreactor or a microchemical plant. In this case, the granulating apparatus 40 joins the raw material liquids 4A and 4B via the respective flow paths 41 and 42. The upstream end of the arc-shaped channel 13 of the microchannel device 10 is attached to the junction of the channels 41 and 42 of the granulation device 40. In the arc-shaped channel 13, a suspension is generated by the raw material liquids 4 </ b> A and 4 </ b> B from the granulating device 40, and thereafter, the fine particles in the suspension are classified and separated. According to this configuration, it is possible to construct a system with no dead space capable of continuously processing from generation of a suspension to classification and separation of fine particles.
[0045]
In the above embodiment, the example of the microchannel device 10 including one unit including the inlet port 16, the flow path (13 to 15), and the outlet ports 17, 18 has been described, but the present invention is not limited to this. Not done.
For example, as in a microchannel device 45 shown in FIGS. 15A and 15B, a plurality of units 46 may be attached in the thickness direction and connected in parallel. In each unit 46, the inlet ports 16 are continuously formed, the outlet ports 17 are continuously formed, and the outlet ports 18 are continuously formed. The channels (13 to 15) of each unit 46 are independent.
[0046]
In the microchannel device 45 having the above configuration, the suspension 47 to be operated is taken in from the common inlet port 16 and distributed to the channels (13 to 15) of each unit 46. Then, the suspensions (including many small particles) after passing through the inner branch passages 14 of the respective units 46 are merged and discharged at the common outlet port 17. Further, the suspension (including a large amount of fine particles) after passing through the outer branch channel 15 of each unit 46 is merged and discharged at the common outlet port 18.
[0047]
Thus, according to the microchannel device 45, multistage parallel operation becomes possible, and the throughput (flow rate) of the suspension can be increased (Numbering-up). Specifically, in the case where the unit 46 includes N units, the throughput of the suspension can be increased N times. At this time, the classification / separation performance of the apparatus does not change with the number of units. That is, the throughput of the suspension can be increased while keeping the classification / separation performance constant.
[0048]
Also, as in a microchannel device 48 shown in FIGS. 16A to 16C, the inlet port 16 and the outlet ports 17 and 18 are made to penetrate to the surface 6B opposite to the surface 6A for taking in and out the suspension. The rods 51 to 53 may be inserted from the surface 6B into the through holes (16 to 18). In this case, it is necessary to make the insertion lengths L1 and L2 of the rods 51 to 53 in the through holes (16 to 18) equal.
[0049]
In the microchannel device 48, even if the suspension 47 is taken in from the common inlet port 16, the suspension does not flow into the unit 46 from the opposite surface 6B to the tip of the rod 51. Can be arbitrarily adjusted according to the insertion lengths L1 and L2 of the rods 51 to 53.
Therefore, for example, in the case of the microchannel device 48 configured by stacking the units 46 of 100 stages, even if the flow rate of the suspension 47 changes in the range (100 steps) from the maximum flow rate to the minimum flow rate, By adjusting the insertion lengths L1 and L2 of the rods 51 to 53 accordingly and appropriately setting the number of operating units, the same classification / separation performance can be maintained.
[0050]
Conversely, if the flow rate of the suspension 47 taken into the microchannel devices 45 and 48 is kept constant regardless of the number of units, the classification / separation performance can be changed. In the conventional small cyclone, if the flow rate is changed, the performance (particle size that can be classified and separated) also changes. However, according to the above multistage parallel operation, one of the flow rate and the performance is changed while the other is kept constant. Things can be done easily.
[0051]
Further, as in a micro channel device 55 shown in FIG. 17, a plurality of units 46 may be attached in the thickness direction and connected in series. For series connection, the directions of the adjacent units 46 are alternately reversed left and right. The output port 18 on the upstream side (labeled 6U in the figure) of the adjacent unit 46 is connected to the input port 16 on the downstream side (labeled 6D in the figure), The output port 17 is connected continuously between the units 46, and the flow paths (13 to 15) of the units 46 are independent.
[0052]
In the microchannel device 55 having the above-described configuration, the suspension 47 to be operated is taken in from the first-stage inlet port 16, and the suspension containing small particles is supplied to the inner outlet through the inner branch channel 14 of each stage. Merge into port 17. Further, the suspension containing large fine particles flows into the inlet port 16 of the next stage through the outer branch channel 15. According to this multi-stage series operation, the performance of removing small particles is improved, and the classification / separation accuracy of the apparatus is improved (serial numbering up).
[0053]
Also, when a plurality of units 46 are attached and numbered up as in the case of the microchannel devices 45, 48, and 55 in FIGS. 15 to 17, the flow channel formed in each unit 46 has an extremely shallow micro-scale. (For example, 170 μm), each unit 46 can be extremely thin (for example, 1 mm or less). Therefore, it is possible to avoid an increase in the size of the device due to numbering up. For example, even when 100 units of 1 mm units 46 are stacked, the thickness of the entire apparatus can be suppressed to about 10 cm.
[0054]
In the above-described embodiment, two branch channels 14 and 15 are provided on the downstream side of the arc-shaped channel 13. However, the number of branch channels may be three or more (see FIGS. 18 and 19). The classification / separation floor can be adjusted according to the number of outlet-side branch flow paths.
Further, in the above-described embodiment, the arc-shaped channel 13 is formed in a semicircular shape, but the present invention is not limited to this. The arc-shaped channel 13 can be constituted by a part (arbitrary length) of a circular shape. However, it is preferable to ensure a length in which the Dean vortex can be generated in the suspension flowing toward the downstream side. The shape of the arc-shaped flow path 13 is not limited to a circular shape, but may be any shape such as an elliptical shape or a parabolic shape.
[0055]
Further, in the above-described embodiment, the cross-sectional shape of the flow path (13 to 15) is rectangular, but the present invention is not limited to this. The cross-sectional shape may be other than rectangular (for example, circular). The size of the cross section can be arbitrarily determined as long as at least one side of the flow path is 1 mm or less and the cross sectional area is sufficiently small so that a sufficient centrifugal force can be obtained. The size of the cross section may be determined according to the size of the fine particles in the suspension to be operated.
[0056]
Further, in the above-described embodiment, an example has been described in which the width of the outer branch flow path 15 is doubled on the downstream side, but the width may be equal to that of the inner branch flow path 14. Classification performance can be changed by arbitrarily controlling the flow rate ratio in each branch channel according to the width of each branch channel. As a method of controlling the flow ratio, a method of changing the length of each branch flow path, a method of adjusting the pressure applied to the outlet ports 17 and 18, and the like other than changing the width of each branch flow path can be considered. In the former case, the pressure loss increases according to the length of the branch flow path, and as a result, the flow rate in the long branch flow path can be reduced. In the latter case, the flow rate of the branch flow path connected to the outlet port to which a high pressure is applied can be reduced.
[0057]
In addition, the present invention is not limited to a polydisperse suspension, and can be applied to a suspension having a very small particle size distribution width that can be regarded as a monodisperse in practical use.
Furthermore, in the above-described embodiment, the micro-scale channels (13 to 15) are provided between the two acrylic plates 11 and 12, but the present invention is not limited to this. For example, a similar micro-scale channel may be provided between two plate members made of other materials such as glass, various polymers, silicon wafer, copper, and stainless steel.
[0058]
Further, in the above-described embodiment, an example in which a groove is formed in one of the two plate members and the groove is covered with the other plate member has been described, but the present invention is not limited to this. For example, a three-dimensional hollow closed channel may be formed directly in one plate member. In this case, there is an advantage that the flow path can be reliably sealed. Therefore, when the operating pressure is high due to the properties of the suspension, it is preferable to form a hollow channel in one plate member. For this formation, for example, a micro stereolithography method can be used.
[0059]
However, when a hollow flow path is formed in one plate member, when a plurality of units 46 are bonded like the microchannel devices 45, 48, and 55 in FIGS. At a disadvantage. For this reason, when the operating pressure is low due to the nature of the suspension, it is preferable to form a groove on the surface of the unit 46 giving priority to the size of the device.
[0060]
Further, as a modified example of the microchannel device 55 (serial numbering up) in FIG. 17, a configuration like the microchannel device 60 in FIG. 20 can be adopted. In the microchannel device 60, the outlet port 17 of the inner branch flow path at the previous stage is connected to the inlet port 16 at the next stage. With this configuration, the performance of removing large fine particles is improved.
[0061]
【The invention's effect】
As described above, according to the present invention, even if the supply amount of the suspension is very small, the fine particles in the suspension can be reliably classified and separated.
[Brief description of the drawings]
FIG. 1 is a top view of a microchannel device 10. FIG.
FIG. 2 is an enlarged view of an arc-shaped channel 13;
FIG. 3 is an enlarged view of a branch point of a flow path (13 to 15) and an outer branch flow path 15;
FIG. 4 is a sectional view taken along the line AA of FIG.
FIG. 5 is a sectional view taken along the line BB of FIG. 1;
FIG. 6 is a view showing a state in which a micro feeder 37 and sample bottles 38 and 39 are attached to the micro channel device 10.
FIG. 7 is a cross-sectional view illustrating a suspension flowing from an arc-shaped channel 13 into an inner branch channel 14 and an outer branch channel 15;
FIG. 8 is a cross-sectional view illustrating a centrifugal force F1 and Dean vortices F2 and F3 generated in the arc-shaped channel 13.
FIG. 9 is a schematic diagram illustrating a classification operation.
FIG. 10 is a schematic diagram illustrating a separation operation.
FIG. 11 shows specific measurement results of a classification operation performed by the microchannel device 10.
FIG. 12 shows specific measurement results of a classification operation performed by the microchannel device 10.
FIG. 13 is a schematic diagram illustrating a concentration operation.
FIG. 14 is a diagram showing an example of connection with a minute granulation device 40.
15A is a diagram illustrating an external configuration of a microchannel device 45 capable of performing multi-stage parallel operation, and FIG. 15B is a diagram illustrating a schematic configuration thereof.
FIG. 16 is a schematic configuration diagram of a microchannel device 48 capable of performing multi-stage parallel operation.
FIG. 17 is a schematic configuration diagram of a microchannel device 55 capable of performing multi-stage serial operation.
FIG. 18 is a configuration diagram when three branch flow paths are provided.
FIG. 19 is a configuration diagram when four branch flow paths are provided.
FIG. 20 is a schematic configuration diagram of a microchannel device 60.
[Explanation of symbols]
10 Microchannel device
13 Arc-shaped channel
14 Inside branch channel
15 Outside branch channel
16 entrance port
17, 18 exit port

Claims (6)

An inlet port for taking in the suspension,
A curved flow path having one end attached to the inlet port,
A plurality of branch channels attached downstream of the channel,
A microchannel attached to one downstream end of each of the branch flow paths, comprising: the curved flow path; and a plurality of outlet ports for discharging a suspension after passing through the branch flow path. apparatus. The microchannel device according to claim 1,
The microchannel device according to claim 1, wherein the curved flow path is constituted by a part of a circular shape. The microchannel device according to claim 2,
The curved flow path satisfies the following condition (Q / A) ² /, where A is the cross-sectional area, R is the radius of curvature, and Q is the flow rate of the suspension taken into the inlet port. R> 9.8
A microchannel device characterized by the above-mentioned. The microchannel device according to any one of claims 1 to 3,
The micro-channel device according to claim 1, wherein the curved flow path has a length capable of generating a Dean vortex in the suspension flowing toward the downstream side. The microchannel device according to any one of claims 1 to 4,
A plurality of units comprising the inlet port, the curved flow path, the plurality of branch flow paths, and the plurality of outlet ports,
The plurality of units are connected in parallel with each other. The microchannel device according to any one of claims 1 to 4,
A plurality of units comprising the inlet port, the curved flow path, the plurality of branch flow paths, and the plurality of outlet ports,
The plurality of units are connected in series with each other.

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