JP2017035649A - Freezing separation device and freezing separation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a freezing separation device and a freezing separation method capable of improving concentration efficiency (or making a solvent to be separated highly purified).SOLUTION: A freezing separation device 1A freezing and separating at least a part of a solvent from a solution B includes: a contact member 12 contacting with the solution B; a vibrating part 13 applying vibration to the contact member 12; and a cooling part 14 freezing the solvent positioning in the vicinity of a boundary between the contact member 12 and the solution B by cooling the contact member 12. In the freezing separation device 1A, the solution B is concentrated or the purity of the solvent is increased by separating at least a part of the solvent from the solution B.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a freeze separation apparatus and a freeze separation method.

  Patent Document 1 discloses a technique related to a freeze concentration separation apparatus. In the apparatus described in this document, first, water that has absorbed the solvent is frozen in an ice making machine, the solvent is not frozen due to the difference in freezing point, and the water is frozen and separated into ice particles and concentrated water. Next, ice particles and concentrated water are accumulated in a cold storage tank and irradiated with ultrasonic waves. Thereby, the air bubbles taken into the ice particles are removed. Non-Patent Document 1 discloses a method of performing freeze concentration separation while irradiating a solution with ultrasonic waves.

JP 2003-145137 A

Kenji Kawasaki, “Freeze Concentration Separation Method Using Ultrasonics”, Faculty of Engineering, Ehime University, 79th Seminar on Applied Chemistry

  In the industry, freeze concentration techniques are often used to concentrate liquid foods such as instant coffee, various juices, beer, wine, and dairy products. In the freeze concentration technique, the solute concentration in the unfrozen solution can be increased by cooling the solution to form a frozen portion (eg, ice) having a low solute concentration. For example, by bringing a low-temperature member into contact with the solution, the solvent can be frozen in the vicinity of the surface of the member. Such a freeze concentration technique is also preferably used when a high-purity solvent is separated from a solution.

  In the conventional freeze concentration technique, for example, a stirring frame or circulation of the solution is performed in order to prevent the solute concentration in the solution in the vicinity of the frozen portion from increasing and to increase the solvent purity of the frozen portion. However, even when the solution is stirred or circulated, the solute located on the surface (frozen surface) of the frozen portion hardly moves due to the viscosity of the solution. This hinders high purity of the frozen portion and causes reduction in concentration efficiency (or low purity of the separated solvent).

  As disclosed in Non-Patent Document 1, there is a method for irradiating a solution with ultrasonic waves, but this method is a vibrator for appropriately irradiating ultrasonic waves on a frozen surface that moves with time. It is extremely difficult to adjust the position, and is hardly applied in industry.

  The present invention has been made in view of such problems, and an object thereof is to provide a freeze separation apparatus and a freeze separation method capable of improving the concentration efficiency (or increasing the purity of the solvent to be separated). To do.

  In order to solve the above-described problems, a freeze separation apparatus according to the present invention is an apparatus that freezes and separates at least a part of a solvent from a solution, and includes a contact member that contacts the solution, and a vibration member that applies vibration to the contact member. It is characterized by comprising a vibrating part and a cooling part for partially freezing the solvent by cooling the contact member.

  Further, the freeze separation method according to the present invention is a method of freezing and separating at least a part of a solvent from a solution, and in a state in which the contact member is in contact with the solution, the contact member is vibrated while being vibrated. The solvent is partially frozen by cooling.

  According to the above-described freeze separation apparatus and freeze separation method, the surface (frozen surface) of the frozen portion of the solution generated near the interface with the contact member is in contact with the non-frozen portion while vibrating. Thereby, the solute in the non-frozen portion existing in the vicinity of the frozen surface is easily separated from the frozen surface. Therefore, compared to conventional methods using only agitation and circulation, freezing can be carried out while effectively reducing the solute concentration on the freezing surface, thus improving the concentration efficiency (or increasing the purity of the separated solvent). Is possible.

  Further, the freeze separation apparatus may be characterized in that the contact member is immersed in the solution from the liquid surface of the solution. Thereby, a simple freeze separation apparatus can be provided.

  In the freeze separation device, the contact member may have a tubular shape, and the cooling unit may send a cooled liquid or gas into the tube. Thereby, a contact member can be cooled by simple structure.

  In addition, the above-described freeze separation apparatus may be characterized in that the contact member constitutes a part of a container that stores the solution.

  The freeze separation method may be characterized in that the solution is concentrated by separating at least a part of the solvent from the solution. Thereby, it is possible to provide a freeze concentration method with high concentration efficiency (that is, a high distribution coefficient). Alternatively, the freeze separation method described above may be characterized in that the purity of the solvent is increased by separating at least a part of the solvent from the solution. Thereby, the method which can extract a solvent with high purity from the solution can be provided.

  According to the present invention, it is possible to provide a freeze separation apparatus and a freeze separation method capable of improving the concentration efficiency (or increasing the purity of the solvent to be separated).

FIG. 1 is a cross-sectional view showing a configuration of a freeze separation device according to a first embodiment of the present invention. FIG. 2 is a flowchart showing a freeze separation method using the freeze separation apparatus of the first embodiment. FIG. 3 is a diagram showing a conventional freeze separation method. FIG. 4 is a cross-sectional view showing the configuration of the freeze separation device according to the second embodiment of the present invention. FIG. 5 is a cross-sectional view showing the configuration of the freeze separation apparatus according to the third embodiment of the present invention. FIG. 6 is a cross-sectional view showing the configuration of the freeze separation apparatus according to the fourth embodiment of the present invention. FIG. 7 is a graph showing the results of an example for confirming the effects of the present invention.

  Embodiments of a freeze separation apparatus and a freeze separation method according to the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
FIG. 1 is a cross-sectional view showing a configuration of a freeze separation apparatus 1A according to the first embodiment of the present invention. The freeze separation device 1A is a device that freezes and separates at least a part of the solvent from the solution B. The freeze separation apparatus 1A is used as an apparatus for concentrating the solution B by separating the solvent from the solution B, or as an apparatus for increasing the purity of the solvent by separating the solvent from the solution B. When this freeze separator 1A is used as a concentrator, it is suitably used for concentrating instant coffee, various juices, beer, wine, dairy products and the like in the food field. Or it is used suitably also for the concentration of the sample in the case of analysis in biology, medical treatment / medical field.

  As shown in FIG. 1, the freeze separation device 1 </ b> A of the present embodiment includes a container 11 that stores a solution B, a contact member 12 that contacts the solution B, and an excitation that applies minute mechanical vibrations to the contact member 12. And a cooling unit 14 that cools the contact member 12. The solution B is, for example, an aqueous solution of a target substance (solute). When the freeze separator 1A is used for food production, the container 11 has a size of, for example, several meters to several centimeters as a part of factory equipment, and the freeze separator 1A is used for analyzing samples. When used, the laboratory apparatus has a diameter of, for example, several centimeters to several millimeters.

  The contact member 12 has a two-layered tube shape in which the inner tube is accommodated in the outer tube, and the inner tube and the outer tube communicate with each other at the end of the contact member 12. The contact member 12 is immersed in the solution B from the liquid level B1 of the solution B. At this time, the longitudinal direction of the contact member 12 coincides with the depth direction of the solution B.

  The vibration unit 13 is attached to a portion of the contact member 12 exposed from the solution B. The vibration unit 13 may vibrate the contact member 12 by electromagnetic force such as a solenoid coil or an electric motor, and vibrates the contact member 12 by a vibration device using compressed air given from the outside of the freeze separation device 1A. Alternatively, the contact member 12 may be vibrated using an electronic element such as a piezoelectric element or an ultrasonic oscillator. A suitable vibration frequency of the contact member 12 is, for example, 20 Hz to 100 kHz, and more preferably, for example, 100 Hz. Moreover, the suitable amplitude of the contact member 12 is 0.1 mm-30 mm, for example, More preferably, it is 1 mm, for example. The vibration direction of the contact member 12 can be set in various directions such as vertical or horizontal with respect to the contact surface with the solution B.

  The cooling unit 14 cools the contact member 12 by sending a cooled liquid or gas (arrow F in the figure) to the inner tube (or outer tube) of the contact member 12. The liquid or gas F is discharged from the outer tube (or inner tube) of the contact member 12 to the outside of the contact member 12. As the liquid or gas F fed into the contact member 12, various liquids or gases such as chlorofluorocarbon and alcohol can be used. In the case of Freon gas, the contact member 12 is preferably made of metal. In the case of alcohol, the contact member 12 may be made of a resin such as rubber. By the cooling of the contact member 12 by the cooling unit 14, the solvent located in the vicinity of the boundary between the contact member 12 and the solution B is frozen, and a frozen portion B2 is formed.

  FIG. 2 is a flowchart showing a freeze separation method using the freeze separation apparatus 1A of the present embodiment. As shown in FIG. 2, in this freeze separation method, the contact member 12 is first immersed in the solution B, and the surface of the contact member 12 is brought into contact with the solution B (step S11). Next, while maintaining the contact state, the vibration member 13 starts to apply vibration to the contact member 12 (step S12). And cooling of the contact member 12 is started by the cooling unit 14 (step S13). Thereby, the frozen part B2 of the solvent is formed on the surface of the contact member 12. Thereafter, the frozen portion B2 is taken out from the solution B together with the contact member 12 (step S14).

  The effects obtained by the freeze separation apparatus 1A and the freeze separation method according to the present embodiment described above will be described in comparison with conventional methods. FIG. 3 is a diagram showing a conventional freeze separation method. In the conventional method, first, the solution B containing the solute B3 is accommodated in the container 101 (FIG. 3A), and the container 101 is cooled while stirring the solution B by the stirrer 102. As a result, the solution B is gradually frozen from the portion in contact with the container 101, and a frozen portion B2 is formed (FIG. 3B). At this time, since the concentration of the solute B3 in the frozen portion B2 becomes lower than the concentration of the solute B3 in the non-frozen portion, the concentration of the solute B3 in the non-frozen portion gradually increases. Finally, the solution B can be concentrated by removing the non-frozen portion (FIG. 3C).

  However, in such a conventional method, the solute B3 located on the surface (frozen surface) of the frozen portion B2 hardly moves due to the viscosity of the solution B. This leads to an increase in the concentration of the solute B3 in the frozen portion B2, which causes a reduction in concentration efficiency.

  On the other hand, according to the freeze separation device 1A and the freeze separation method of the present embodiment, the surface (frozen surface) of the frozen portion B2 generated near the interface with the contact member 12 vibrates with the non-frozen portion of the solution B while vibrating. Touch. Thereby, the solute in the non-frozen portion existing in the vicinity of the frozen surface is easily separated from the frozen surface. Therefore, compared to conventional methods using only agitation and circulation, freezing can be carried out while effectively reducing the solute concentration on the freezing surface, thus improving the concentration efficiency (or increasing the purity of the separated solvent). Is possible. Further, since an electronic element such as a piezo element or an ultrasonic oscillator can be used as the vibration unit 13, the power consumption can be reduced as compared with the conventional technique using the stirrer 102 operated by a motor or the like. In addition, unlike the apparatus described in Non-Patent Document 1, it is not necessary to adjust the position of the ultrasonic vibrator or the like during the separation operation, so that stable freeze separation can be performed with a simple operation.

  Further, the freeze separation method of the present embodiment may be characterized in that the solution B is concentrated by separating at least a part of the solvent from the solution B. Thereby, it is possible to provide a freeze concentration method with high concentration efficiency (that is, a high distribution coefficient). Alternatively, the freeze separation method of the present embodiment may be characterized in that the purity of the solvent is increased by separating at least a part of the solvent from the solution B. Thereby, the method which can extract a solvent with high purity from the solution B can be provided.

  Further, as in the present embodiment, the contact member 12 may be immersed in the solution B from the liquid level B1 of the solution B. Thereby, it is possible to provide a freeze separation apparatus 1A that can be easily used, for example, in the case of analysis in the fields of biology, medicine, and medicine. Moreover, like this embodiment, the contact member 12 is exhibiting the tubular shape, and the cooling part 14 may send the cooled liquid or gas in this pipe | tube. Thereby, the contact member 12 can be cooled with a simple configuration.

(Second Embodiment)
FIG. 4 is a cross-sectional view showing a configuration of a freeze separation device 1B according to the second embodiment of the present invention. Similarly to the freeze separation device 1A, this freeze separation device 1B also freezes and separates at least a part of the solvent from the solution B.

  As shown in FIG. 4, the freeze separation device 1 </ b> B of the present embodiment includes a container 21 that stores the solution B, a plate-like contact member 22 that contacts the solution B, and a vibration unit that applies vibration to the contact member 22. 23 and a cooling unit 24 for cooling the contact member 22. Unlike the first embodiment, in this embodiment, the contact member 22 closes the bottom of the cylindrical container 21, and constitutes a part of the container for storing the solution B together with the container 21.

  Further, the vibration unit 23 of the present embodiment may have the same configuration as the vibration unit 13 of the first embodiment. FIG. 3 shows a solenoid coil 23b and a movable iron core 23c as an example of the vibration unit 23. When a drive voltage is applied from both ends of the solenoid coil 23b from the AC power source 23a, an electromagnetic force is generated in the solenoid coil 23b to vibrate the movable iron core 23c. One end of the movable iron core 23 c is fixed to the contact member 22 via the cooling unit 24, and the vibration of the movable iron core 23 c is transmitted to the contact member 22.

  As the cooling unit 24, for example, a thermoelectric element such as a Peltier element is used to cool the plate-like contact member 22. The cooling unit 24 is in contact with the back surface of the contact member 22 (that is, the surface opposite to the contact surface with the solution B), and removes heat from the contact member 22 according to the applied voltage. Thereby, the solvent located in the contact surface vicinity with the contact member 22 freezes, and frozen part B2 is formed.

  According to the freeze separation device 1B of the present embodiment, the same effects as the freeze separation device 1A of the first embodiment can be obtained. That is, the surface (frozen surface) of the frozen portion B2 generated near the interface with the contact member 22 contacts the non-frozen portion of the solution B while vibrating. Thereby, since the solute in the non-frozen portion is easily separated from the freezing surface, the concentration of the solute on the freezing surface is reduced, and the concentration efficiency can be improved (or the purity of the separated solvent can be increased).

(Third embodiment)
FIG. 5 is a cross-sectional view showing a configuration of a freeze separation device 1C according to the third embodiment of the present invention. Similarly to the freeze separation device 1A, this freeze separation device 1C also freezes and separates at least a part of the solvent from the solution B. As shown in FIG. 5, the freeze separation device 1 </ b> C of the present embodiment includes a contact member 32 instead of the contact member 12 of the first embodiment. The contact member 32 of this embodiment has a configuration in which one tubular member is bent in a U shape. The cooling unit 14 sends the cooled liquid or gas F to one end of the tubular member. The liquid or gas F is discharged from the other end of the tubular member. Since the other configuration excluding the contact member 32 is the same as that of the first embodiment, detailed description thereof is omitted.

  The configuration of the contact member is not limited to the first embodiment, and can take various forms such as the contact member 32 of the present embodiment. Whatever form the contact member has, the effects of the first embodiment can be suitably achieved by applying vibrations by the excitation unit and cooling by the cooling unit.

(Fourth embodiment)
FIG. 6 is a cross-sectional view showing a configuration of a freeze separation apparatus 1D according to the fourth embodiment of the present invention. Similarly to the freeze separation device 1A, this freeze separation device 1D also freezes and separates at least a part of the solvent from the solution B. As shown in FIG. 6, the freeze separation device 1 </ b> D of this embodiment includes a contact member 42 instead of the contact member 12 of the first embodiment. The difference between the contact member 42 and the contact member 12 of the first embodiment is the shape of the surface in contact with the solution B. That is, while the surface of the contact member 12 of the first embodiment is flat, unevenness is repeatedly formed on the surface 42a of the contact member 42 of the present embodiment. Thereby, since the surface (frozen surface) of the frozen portion B2 is also uneven, the solute in the vicinity of the frozen surface is more easily separated from the frozen surface when the contact member 42 vibrates. Therefore, the effect of the first embodiment becomes more remarkable.

(Example)
FIG. 7 is a graph showing the results of an example for confirming the effects of the present invention. In this example, an aqueous solution in which red food (red No. 102) was dissolved was designated as solution B. Then, the solution B was freeze-concentrated using a device in which a Peltier element as a cooling unit was attached to a metal plate-like contact member, and the contact member was fixed to a solenoid coil as a vibration unit. The horizontal axis of FIG. 7 shows a partition coefficient, that is, a value obtained by dividing the solute concentration in the frozen portion B2 by the solute concentration in the non-frozen portion. The vertical axis in FIG. 7 indicates the voltage applied to the Peltier element. Plot P1 in the figure shows the result when a sinusoidal vibration having a frequency of 100 Hz and an amplitude of 1 mm is applied to the contact member by the solenoid coil. Plot P2 shows the result when no vibration is applied to the contact member.

  As shown in plot P2 of FIG. 7, the distribution coefficient was about 0.7 when freeze separation was performed without applying vibration to the contact member. On the other hand, the distribution coefficient when freeze separation was performed while applying vibration to the contact member was about 0.2. From this result, it can be seen that the solute concentration in the frozen portion B2 could be greatly reduced by vibrating the contact member.

  The freeze separation apparatus and freeze separation method according to the present invention are not limited to the above-described embodiments, and various other modifications are possible. For example, you may combine each element of each embodiment mentioned above according to a required objective and effect. The contact member only needs to be a member in contact with the solution, and can have various shapes and structures. The vibration unit is not limited to the above-described example as long as it can apply vibration to the contact member. The cooling unit is not limited to the above-described example as long as it can cool the contact member.

  DESCRIPTION OF SYMBOLS 1A-1D ... Freezing separation apparatus, 11, 21 ... Container, 12, 22, 32, 42 ... Contact member, 13, 23 ... Excitation part, 14, 24 ... Cooling part, B ... Solution, B1 ... Liquid surface, B2 ... Frozen part, F ... Liquid or gas.

Claims (7)

An apparatus for freezing and separating at least a part of a solvent from a solution,
A contact member in contact with the solution;
An excitation unit for applying vibration to the contact member;
A cooling unit for partially freezing the solvent by cooling the contact member;
A freeze separation apparatus comprising:   The freeze separation apparatus according to claim 1, wherein the contact member is immersed in the solution from a liquid level of the solution.   The freeze separation device according to claim 1 or 2, wherein the contact member has a tubular shape, and the cooling unit sends a cooled liquid or gas into the tube.   The freeze separation apparatus according to claim 1, wherein the contact member constitutes a part of a container for storing the solution. A method of freezing and separating at least a part of a solvent from a solution,
A freeze separation method, wherein the solvent is partially frozen by cooling the contact member while applying vibration to the contact member while the contact member is in contact with the solution.   The freeze separation method according to claim 5, wherein the solution is concentrated by separating the at least part of the solvent from the solution.   The freeze separation method according to claim 5, wherein the purity of the solvent is increased by separating the at least part of the solvent from the solution.

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