Processing apparatus and processing method

Abstract

The present invention provides a processing apparatus and a processing method that improve the processing efficiency of reducing the molecular weight of the liquid to be processed. [Solution] The processing apparatus 1 is a processing apparatus 1 that processes a liquid to be processed by generating plasma in a discharge gas, and comprises a chamber 10, a pair of electrodes 112 for generating plasma, and a dielectric 113 provided on the surface of the pair of electrodes 112, wherein the chamber 10 has a first containment section 12 for containing the discharge gas, a second containment section 13 for containing the liquid to be processed, and a plasma generating section 111 connecting the first containment section 12 and the second containment section 13, and the pair of electrodes 112 are provided facing the plasma generating section 111.

Description

[Technical Field]

[0001] This invention relates to a processing apparatus and a processing method for processing a liquid to be processed using plasma generated in a discharge gas. [Background technology]

[0002] Conventionally, methods for depolymerizing high molecular weight organic compounds have been studied. For example, monomers obtained by depolymerizing high molecular weight alginic acid and high molecular weight fucoidan, which are abundant in brown algae, are used as raw materials for health and medical foods. Furthermore, plasma-based depolymerization processes are attracting attention as a method for depolymerizing high molecular weight organic compounds because they can efficiently reduce molecular weight without the need for heating.

[0003] For example, Patent Document 1 discloses a technique in which a gas supply unit pressurizes and pumps gas into the liquid storage unit through a gas passage formed in a partition wall separating the liquid storage unit and the gas storage unit, thereby generating bubbles in the liquid storage unit and generating plasma within those bubbles. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2012-164559 [Overview of the project] [Problems that the invention aims to solve]

[0005] According to the processing method disclosed in Patent Document 1, when bubbles are introduced into the liquid storage section 4 through the gas passage 3a of the ceramic member 3, the sensing section 61 detects a change in the impedance of the liquid (the liquid to be processed) in the liquid storage section 4, and according to this detected amount, a plasma voltage is applied between the first electrode 12 provided in the gas storage section 5 and the second electrode 13 provided in the liquid storage section 4. Thus, Patent Document 1 is premised on generating plasma in the bubbles introduced into the liquid (the liquid to be processed) in the liquid storage section 4 and processing the liquid (the liquid to be processed) in the region around the bubbles. However, according to this processing method, the generation position of the plasma and the amount of the liquid (the liquid to be processed) to be processed become unstable depending on the presence or absence of the bubbles and the positions of the respective bubbles, and moreover, since the bubbles after the plasma treatment are present in the liquid (the liquid to be processed), there is a concern that the processing efficiency of reducing the molecular weight of the liquid to be processed cannot be improved.

[0006] Therefore, the present invention has been devised in view of the above-described problems, and an object thereof is to provide a processing apparatus and a processing method in which the processing efficiency of reducing the molecular weight of the liquid to be processed is improved.

Means for Solving the Problems

[0007] The processing apparatus according to the first invention is a processing apparatus that generates plasma in a discharge gas to process a liquid to be processed, and includes a chamber, a pair of electrodes for generating the plasma, and a dielectric provided on the surfaces of the pair of electrodes. The chamber has a first storage section that stores the discharge gas, a second storage section that stores the liquid to be processed, and a plasma generation section that connects the first storage section and the second storage section, and the pair of electrodes are provided facing the plasma generation section.

[0008] The processing apparatus according to the second invention is characterized in that, in the first invention, it further includes a pressure sensor for measuring the pressure in at least one of the first storage section or the second storage section.

[0009] The processing apparatus in the third invention is characterized in that, in the first or second invention, it further comprises a separation mechanism provided between the first housing and the second housing, and an impermeable portion provided on the main surface of the separation mechanism on the side of the second housing, wherein the affinity for the liquid to be processed is lower than that of the main surface.

[0010] The processing apparatus in the fourth invention further comprises, in the first or second invention, a liquid to be processed introduction unit for introducing the liquid to be processed into the second containment unit, and a liquid to be processed discharge unit for discharging the liquid to be processed from the second containment unit, wherein a plurality of plasma generating units are provided in the flow direction of the liquid to be processed from the liquid to be processed introduction unit to the liquid to be processed discharge unit.

[0011] The processing apparatus in the fifth invention is characterized in that, in the first or second invention, the pair of electrodes are arranged spaced apart in the direction from the first housing to the second housing.

[0012] The processing method according to the sixth invention is a processing method for processing a liquid to be processed by generating plasma in a discharge gas, and is characterized by comprising: a gas supply step of supplying the discharge gas to a plasma generating unit that connects a first housing unit containing the discharge gas and a second housing unit containing the liquid to be processed in a chamber; a liquid to be processed supply step of supplying the liquid to be processed to the second housing unit; and a plasma processing step of generating the plasma in the discharge gas of the plasma generating unit supplied in the gas supply step, using a pair of electrodes having a dielectric material on their surface and positioned toward the plasma generating unit, thereby processing the liquid to be processed supplied in the liquid to be processed supply step. [Effects of the Invention]

[0013] According to the first to fifth inventions, the chamber has a plasma generating section connecting a first containment section and a second containment section. A pair of electrodes are provided facing the plasma generating section. That is, an interface can be formed between the liquid surface of the liquid to be processed contained in the second containment section and the discharge gas in the plasma generating section. Therefore, by using the pair of electrodes provided facing the plasma generating section to generate plasma near the interface between the liquid to be processed and the discharge gas, the generation of bubbles in the liquid to be processed can be suppressed. As a result, the obstruction of the flow of the liquid to be processed by bubbles can be suppressed, and the processing efficiency of reducing the molecular weight of the liquid to be processed can be improved.

[0014] Furthermore, according to the first to fifth inventions, the processing apparatus includes a dielectric material provided on the surface of a pair of electrodes. This prevents foreign matter generated by electrode wear during plasma generation from contaminating the liquid being processed. This improves the processing quality by reducing the molecular weight of the liquid being processed.

[0015] In particular, according to the second invention, the processing apparatus further includes a pressure sensor for measuring pressure in at least one of the first or second housing. That is, the pressure of the discharge gas or the liquid to be processed in the chamber can be adjusted. This allows the position of the interface between the discharge gas and the liquid to be processed to be adjusted. This makes it possible to further improve the processing efficiency in reducing the molecular weight of the liquid to be processed.

[0016] In particular, according to the third invention, the water-impermeable portion is provided on the main surface of the separation mechanism on the side of the second containment portion, and its affinity for the liquid to be treated is lower than that of the main surface. Therefore, it is possible to prevent the liquid to be treated from adhering to the dielectric due to the surface tension of the liquid to be treated. This makes it possible to suppress the decrease in processing efficiency when the liquid to be treated is reduced in molecular weight.

[0017] In particular, according to the fourth invention, multiple plasma generation units are provided in the flow direction of the liquid to be treated from the liquid to be treated introduction section to the liquid to be treated discharge section. Therefore, the liquid to be treated contained in the second containment section is treated by multiple plasmas generated in the plasma generation units. This makes it possible to further improve the processing efficiency in reducing the molecular weight of the liquid to be treated.

[0018] In particular, according to the fifth invention, a pair of electrodes are arranged spaced apart in the direction from the first housing to the second housing. Therefore, plasma can be generated regardless of the shape of the plasma generation unit. This makes it possible to improve the power consumption efficiency used in the process of reducing the molecular weight of the liquid to be processed.

[0019] According to the sixth invention, the method comprises a gas supply step of supplying a discharge gas to a plasma generation unit, a liquid to be processed supply step of supplying a liquid to be processed to a second containment unit, and a plasma processing step of generating plasma in the discharge gas supplied to the plasma generation unit and processing the liquid to be processed supplied to the second containment unit using a pair of electrodes provided facing the plasma generation unit and having a dielectric material on their surface. That is, an interface can be formed between the liquid surface of the liquid to be processed contained in the second containment unit and the discharge gas in the plasma generation unit. Therefore, by generating plasma near the interface between the liquid to be processed and the discharge gas using a pair of electrodes provided facing the plasma generation unit, the generation of bubbles in the liquid to be processed can be suppressed. As a result, the obstruction of the flow of the liquid to be processed by bubbles can be suppressed, and the processing efficiency of reducing the molecular weight of the liquid to be processed can be improved. [Brief explanation of the drawing]

[0020] [Figure 1] Figure 1 is a schematic diagram showing an example of the configuration of the processing apparatus in this embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view corresponding to the AA cross-section of the processing apparatus in Figure 1. [Figure 3]Figure 3(a) is a schematic cross-sectional view showing an example of the configuration inside the chamber in this embodiment, and Figures 3(b) to 3(c) are schematic cross-sectional views showing modified examples of the configuration inside the chamber in this embodiment. [Figure 4] Figure 4 is a flowchart showing an example of the operation of the processing apparatus in this embodiment. [Figure 5] Figure 5 is a schematic cross-sectional view showing an example of the operation of the processing apparatus in this embodiment. [Figure 6] Figures 6(a) and 6(b) are schematic cross-sectional views showing an example of the operation of the processing apparatus in this embodiment. [Figure 7] Figures 7(a) and 7(b) are schematic cross-sectional views showing modified configurations and operations of the processing apparatus in this embodiment. [Figure 8] Figure 8 is a schematic cross-sectional view showing a modified configuration and operation of the processing apparatus in this embodiment. [Figure 9] Figures 9(a) to 9(c) are schematic cross-sectional views showing modified configurations and operations corresponding to the CC cross-section of the processing apparatus in Figure 8, and Figure 9(d) is a perspective view corresponding to a part of Figure 9(c). [Figure 10] Figure 10 is a schematic cross-sectional view showing a modified configuration of the chamber in this embodiment. [Figure 11] Figure 11 is a schematic cross-sectional view showing a modified example of the operation of the processing apparatus in this embodiment. [Figure 12] Figures 12(a) and 12(b) are schematic cross-sectional views showing modified examples of the operation of the processing apparatus in this embodiment. [Figure 13] Figure 13 is a schematic cross-sectional view showing an example of the configuration of a comparative apparatus, which is used in comparison with the apparatus in this embodiment. [Figure 14] Figures 14(a) to 14(c) show examples of operating conditions for comparative apparatuses, which are compared with the apparatus in this embodiment. [Figure 15] Figures 15(a) to 15(c) show examples of operating conditions for the processing apparatus in this embodiment. [Figure 16]Figure 16(a) shows an example of the processing result of a liquid to be treated using a comparative apparatus, which is used in the example to compare with the apparatus in this embodiment, and Figure 16(b) shows an example of the processing result of a liquid to be treated using the apparatus in this embodiment. [Modes for carrying out the invention]

[0021] Hereinafter, an example of a processing apparatus as an embodiment of the present invention will be described in detail with reference to the drawings. In each figure, the second direction Y is defined as one direction that intersects, for example, orthogonal to, the first direction X, and the third direction Z is defined as a direction that intersects, for example, orthogonal to, both the first direction X and the second direction Y. The configurations in each figure are schematically described for explanatory purposes, and the size of each component, the size comparison of each component, etc., may differ from those shown in the figures.

[0022] (Processing device 1) The processing apparatus 1 comprises, for example, a chamber 10, a pair of electrodes 112, and a dielectric 113, as shown in Figure 1. The processing apparatus 1 may also include a separation mechanism 11 for separating the chamber 10 into multiple regions.

[0023] The processing apparatus 1 is externally connected to a gas supply unit 21 for supplying discharge gas to the first containment unit 12, a liquid to be processed supply unit 22 for supplying liquid to be processed to the second containment unit 13, and a power supply unit 23 for supplying power to a pair of electrodes 112 to generate plasma. The processing apparatus 1 can perform a process to reduce the molecular weight of the liquid to be processed contained in the second containment unit 13 by generating plasma using the pair of electrodes 112 in the discharge gas supplied to the plasma generation unit 111 via the first containment unit 12. Hereafter, "processing" of the liquid to be processed will refer to the process of reducing the molecular weight of the liquid to be processed. In Figure 1, an example is shown in which the upper area is the first containment unit 12 and the lower area is the second containment unit 13, but it is not limited to this, and the positional relationship between the first containment unit 12 and the second containment unit 13 and their respective volume ratios may be freely adjusted according to the combination of the shape of the chamber 10, the shape and arrangement angle of the separation mechanism 11, etc. Furthermore, the processing device 1 may be externally connected to, for example, a pressure control unit 24 for adjusting the pressure of the discharge gas or liquid to be processed in the chamber 10. Also, the processing device 1 may have equivalent functions to the externally connected parts 21, 22, 23, and 24, in which case the external connection of those parts may be omitted.

[0024] <<Chamber 10>> Chamber 10 forms a processing space Q in which the processing apparatus 1 processes the liquid to be processed. Chamber 10 is hollow. The liquid to be processed is processed within Chamber 10.

[0025] Chamber 10 includes a first containment section 12, a second containment section 13, and a plasma generation section 111. Chamber 10 also includes a gas introduction section 101 for introducing discharge gas into the first containment section 12, and a gas discharge section 102 for discharging discharge gas from the first containment section 12. Furthermore, Chamber 10 includes a liquid to be processed introduction section 103 for introducing the liquid to be processed into the second containment section 13, and a liquid to be processed discharge section 104 for discharging the liquid to be processed from the second containment section 13.

[0026] The shape of the chamber 10 can be, for example, cylindrical, or any other shape that can maintain a hollow interior. The material used for the chamber 10 is an insulator that has airtightness to the discharge gas and low affinity to the liquid to be processed. Examples of materials used include glass, ceramics (for example, fine ceramics as described in JIS R 1600), and synthetic resins (for example, fluororesin).

[0027] Chamber 10 is sealed, for example, while the liquid to be processed is being treated. In this case, it is possible to prevent substances unrelated to the treatment of the liquid from entering the treatment space Q, and the discharge gas and the liquid to be treated inside chamber 10 can be made less susceptible to the influence of the environment outside chamber 10. This allows the liquid to be treated to be processed efficiently.

[0028] Chamber 10 may, for example, continuously or intermittently discharge the treated liquid and receive the liquid before treatment in a first-in, first-out (FIFO) manner while the liquid to be treated is being processed. This allows for efficient processing of the liquid to be treated. In addition, the discharge gas may also be handled in a first-in, first-out manner in conjunction with the FIFO treatment of the liquid to be treated.

[0029] <<Separation mechanism 11>> The separation mechanism 11 is provided, for example, in the chamber 10. The separation mechanism 11 separates the processing space Q formed by the chamber 10 into a plurality of areas. The separation mechanism 11 forms a first containment section 12, for example, as an area for containing the discharge gas. The separation mechanism 11 forms a second containment section 13, for example, as an area for containing the liquid to be processed. That is, the separation mechanism 11 is provided between the first containment section 12 and the second containment section 13. The separation mechanism 11 may be detachably attached directly to the wall surface of the chamber 10, for example, or it may be inserted into the chamber 10 with a part of it exposed outside the chamber 10. In this embodiment, the separation mechanism 11 is exemplified as a partition wall separating the first containment section 12 and the second containment section 13 within the chamber 10, but it is not limited to this, and it is not necessarily required to provide a separation mechanism 11 as long as the discharge gas and the liquid to be processed within the chamber 10 are separated, nor is it necessary to provide the separation mechanism 11 as a partition wall within the chamber 10. If the separation mechanism 11 is not provided, the discharge gas and the liquid to be treated are separated, for example, by controlling the supply direction, supply amount, and pressure during supply of the discharge gas and the liquid to be treated.

[0030] The separation mechanism 11 has, for example, a plasma generating section 111 that connects a first housing section 12 and a second housing section 13. The separation mechanism 11 is made of, for example, a dielectric 113 and supports a pair of electrodes 112. The separation mechanism 11 is detachably attached to the chamber 10, for example, via the dielectric 113. Hereafter, an example of the separation mechanism 11 will be described in which the dielectric 113 is used as the base material, the plasma generating section 111 that penetrates the dielectric 113, and the pair of electrodes 112 built into the dielectric 113, but it is not limited to this. For example, if the dielectric 113 is provided on the surface of the pair of electrodes 112, the separation mechanism 11 may use a base material of a different material than the dielectric 113. Also, the separation mechanism 11 may be a laminated structure in which the pair of electrodes 112 and the dielectric 113 are joined together. In this case, the separation mechanism 11 may be a laminated structure in which the electrode material (for example, copper) contained in the pair of electrodes 112 is deposited on an oxide ceramic (for example, alumina) as the dielectric 113. Alternatively, the separation mechanism 11 may have a structure in which a dielectric film covering the surface of the pair of electrodes 112 is formed by heating a dielectric 113 placed on the surface of one electrode 112a and the other electrode 112b, which constitute a pair of electrodes 112, using a burner or the like, and welding it to each electrode 112a and 112b. As a substrate different from the dielectric 113, for example, glass, ceramics (for example, fine ceramics described in JIS R 1600), or synthetic resin (for example, fluororesin) can be used.

[0031] The separation mechanism 11 has a first main surface 11f facing the first housing section 12 and a second main surface 11b facing the second housing section 13. The first main surface 11f is in contact with, for example, the discharge gas housed in the first housing section 12. The second main surface 11b is in contact with, for example, the liquid to be processed housed in the second housing section 13. Depending on the properties of the liquid to be processed, the surface of the second main surface 11b may be processed by methods such as coating or attaching a material having low affinity for the liquid to be processed. Specifically, a thin film of fluororesin, silicon resin, etc., may be formed on the surface of the second main surface 11b by methods such as plasma CVD, ion plating, or sputtering. Furthermore, the second main surface 11b may be formed on its surface by a method of generating plasma in trimethylmethoxysilane gas, using, for example, a superhydrophobic thin film as described in "Biometical Superhydrophilic / Superhydrophobic Thin Films, Yasushi Inoue, Nagahiro Saito, Osamu Takai, Surface Technology, Vol. 56, No. 7, pp. 379-384 (2005)".

[0032] The separation mechanism 11 has a shape, for example, that of a plate. As shown in Figure 2, for example, the cross-section of the separation mechanism 11 is such that one or more perforated plasma generating sections 111 are provided on one electrode 112a (the other electrode 112b) covered with a dielectric 113, and the inner circumferential surface of the plasma generating section 111 is covered with the dielectric 113. That is, the dielectric 113 is provided between the plasma generating section 111 and one electrode 112a (the other electrode 112b). Note that the BB cross-section in Figure 2 corresponds to the cross-sectional view of the separation mechanism 11 in Figure 1.

[0033] The shape of the separation mechanism 11 may be plate-shaped or any other shape that can separate the processing space Q into multiple areas. The separation mechanism 11 may have a cross-shaped cross section formed by combining two plate-shaped sections, in which case the processing space Q may be separated into four areas. The separation mechanism 11 may also have an L-shaped cross section formed by combining two plate-shaped sections.

[0034] <<Plasma generation unit 111>> The plasma generation unit 111 connects the first housing unit 12 and the second housing unit 13, for example, as shown in Figure 3(a). The plasma generation unit 111 is provided, for example, penetrating the first main surface 11f and the second main surface 11b. Of the plasma generation unit 111, the interface surface S a This is an opening on the same plane as the second main surface 11b, and indicates the boundary between the plasma generation section 111 and the second housing section 13. (Boundary surface S) a This can, for example, become the interface between the discharge gas contained in the plasma generation unit 111 and the liquid to be processed contained in the second containment unit 13.

[0035] The plasma generating section 111 may be provided in any direction, for example, by penetrating the first main surface 11f and the second main surface 11b along the third direction Z, or by penetrating along any direction. The plasma generating section 111 may also have a shape in which the cross-section becomes smaller from the second housing section 13 towards the first housing section 12, as shown in Figure 3(b).

[0036] The dimensions of the plasma generation unit 111 are designed considering, for example, the shape of the plasma generation unit 111, the surface tension of the liquid to be processed, and the pressure of the discharge gas contained in the first containment unit 12, so that the interface between the discharge gas contained in the plasma generation unit 111 and the liquid to be processed contained in the second containment unit 13 is stable. If the plasma generation unit 111 has a circular hole shape or a polygonal shape, its dimensions are such that they fit within a perfect circle with a diameter of 0.1 mm to 5 mm.

[0037] <<Pair of electrodes 112>> A pair of electrodes 112 are provided facing the plasma generation unit 111. The pair of electrodes 112 are provided, for example, between the first housing unit 12 and the second housing unit 13 and are supported by the separation mechanism 11. The pair of electrodes 112 are arranged spaced apart in the direction from the first housing unit 12 to the second housing unit 13, as shown, for example, in Figure 3(a). The pair of electrodes 112 consists of one electrode 112a and the other electrode 112b, and are arranged spaced apart in the direction from the first housing unit 12 to the second housing unit 13.

[0038] Here, the state in which a pair of electrodes 112 are provided facing the plasma generation unit 111 refers to a state in which, for example, the electrodes 112a and 112b are provided such that a half-line extending from the end of each electrode 112a and 112b on the plasma generation unit 111 side in the direction in which the end of the electrode faces passes through the space of the plasma generation unit 111. Furthermore, the state in which a pair of electrodes 112 are arranged spaced apart in the direction from the first housing unit 12 to the second housing unit 13 refers to a state in which, assuming the electrodes 112a and 112b are provided facing the plasma generation unit 111, each electrode 112a and 112b are arranged spaced apart along a vector parallel to the third direction Z, for example, a vector connecting the starting point in the first housing unit 12 and the ending point in the second housing unit 13. For example, in Figure 3(a), one electrode 112a and the other electrode 112b are arranged spaced apart and parallel along that vector. The arrangement method of each electrode 112a and 112b is not limited to this, and for example, one electrode 112a and the other electrode 112b may be spaced apart along the vector so that their cross-section is roughly in the shape of a V.

[0039] In this case, compared to the case where electrodes 112a and 112b face each other with the plasma generating unit 111 in between (see Figure 10), plasma can be generated regardless of the shape of the plasma generating unit 111. For example, the pair of electrodes 112 can be adjusted and arranged at any interval at which plasma is generated, regardless of the length of the plasma generating unit 111 in the first direction X. This makes it possible to improve the power consumption efficiency used for processing the liquid to be processed. In addition, as shown in Figure 3(c), multiple pairs of electrodes 112 may be provided along the plasma generating unit 111. In this case, even if the shape of the plasma generating unit 111 is longer in the first direction X, it is easier to fill the plasma generating unit 111 with plasma.

[0040] The pair of electrodes 112 generate a potential difference between electrodes 112a and 112b by receiving power from an electrically connected external power supply unit 23. This causes the discharge gas in the plasma generation unit 111, which is the space between electrodes 112a and 112b, to ionize, and plasma is generated. At this time, the pair of electrodes 112 may be partially exposed, for example, to connect to the power supply unit 23, as long as they are not exposed to the processing space Q.

[0041] A dielectric material 113 is provided on the surface of each pair of electrodes 112. In this case, it is possible to prevent foreign matter generated by electrode wear during plasma generation from contaminating the liquid being processed. This improves the processing quality by reducing the molecular weight of the liquid being processed.

[0042] The distance between one electrode 112a and the other electrode 112b is determined based on the Paschen curve, which shows the relationship between the voltage at which a spark discharge occurs (spark voltage), the product of atmospheric pressure and the electrode distance. According to the Paschen curve, the plasma discharge initiation voltage is at its minimum when the Paschen curve is at its minimum value. In this case, plasma can be generated by applying a lower voltage compared to when the Paschen curve is not at its minimum value. In this embodiment, for example, the electrode distance at which the Paschen curve is at its minimum value is preferred. However, in practice, it is conceivable that priority may be given to the arrangement or ease of processing of each electrode 112a, 112b. In such cases, plasma may be generated by arranging or processing each electrode 112a, 112b at a wider distance than the electrode distance at which the Paschen curve is at its minimum value and adjusting the applied voltage. Specifically, the distance between one electrode 112a and the other electrode 112b is, for example, 1 μm to 5 mm. Furthermore, the electrode spacing at which the Paschen curve reaches its minimum value changes depending on the type of discharge gas. For example, when discharging into argon gas at a constant pressure, the electrode spacing at which the Paschen curve reaches its minimum value is approximately 8 μm. The closer the electrode spacing is to 8 μm, the lower the voltage applied, which is preferable because it allows plasma to be generated. The pair of electrodes 112 can be any electrodes that generate plasma in the discharge gas. Examples of combinations of the pair of electrodes 112 include tungsten and platinum group metals, tungsten and copper, etc. Alternatively, the pair of electrodes 112 may be made of the same metal, such as tungsten with tungsten or copper with copper.

[0043] <<Dielectric 113>> The dielectric 113 is provided on at least a portion of the surface of the pair of electrodes 112. The dielectric 113 is provided on the surface of the pair of electrodes 112, for example, as shown in Figure 1. The dielectric 113 may, for example, support the pair of electrodes 112. As the material of the dielectric 113, a dielectric material having airtightness and hydrophobicity is used, for example, glass, ceramics (for example, fine ceramics described in JIS R 1600), synthetic resin (fluororesin, etc.) is used, and specifically alumina is used.

[0044] <<First containment section 12>> The first containment section 12 contains the discharge gas. The first containment section 12 is, for example, one of the multiple regions in which the processing space Q formed by the chamber 10 is separated by the separation mechanism 11, in which the discharge gas is contained. The first containment section 12 is connected to the second containment section 13 via the plasma generation section 111.

[0045] The first containment section 12, as shown in Figure 1 for example, contains the discharge gas introduced from the gas introduction section 101 and has a flow direction for discharging the discharge gas from the gas discharge section 102. The dashed arrow in Figure 1 indicates the flow direction of the discharge gas. A portion of the discharge gas contained in the first containment section 12 may be supplied to the plasma generation section 111.

[0046] The first housing section 12 extends, for example, in the XY plane. The length of the first housing section 12 in the third direction Z is set according to the amount of discharge gas consumed in conjunction with plasma generation, and is, for example, 1 mm to 10 mm.

[0047] <<Second containment section 13>> The second containment section 13 contains the liquid to be processed. The second containment section 13 is, for example, one of the multiple regions in the processing space Q formed by the chamber 10 by the separation mechanism 11, in which the liquid to be processed is contained. The second containment section 13 is connected to the first containment section 12 via the plasma generation section 111.

[0048] The second containment section 13, as shown in Figure 1 for example, contains the liquid to be treated introduced from the liquid to be treated introduction section 103 and has a flow direction for discharging the liquid to be treated from the liquid to be treated discharge section 104. The solid arrows in Figure 1 indicate the flow direction of the liquid to be treated.

[0049] The second housing section 13 extends, for example, in the XY plane direction. The length of the second housing section 13 in the third direction Z is set according to the concentration of the molecules to be decomposed in the liquid to be processed, and is, for example, 1 mm to 2 mm.

[0050] Next, we will describe the gas supply unit 21, the liquid to be processed supply unit 22, the power supply unit 23, and the pressure control unit 24, which are externally connected to the processing device 1.

[0051] <<Gas Supply Department 21>> The gas supply unit 21 supplies discharge gas to the first housing unit 12. The gas supply unit 21 consists of, for example, known solenoid valves and known gas cylinders that are interconnected, and the amount of discharge gas supplied to the first housing unit 12 is determined by operating the opening and closing of the solenoid valves using a power supply (not shown).

[0052] <<Processing liquid supply unit 22>> The liquid to be treated supply unit 22 supplies the liquid to be treated to the second storage unit 13. The liquid to be treated supply unit 22 is composed of, for example, a known solenoid valve and a known liquid to be treated storage tank that are interconnected, and the amount of liquid to be treated supplied to the second storage unit 13 is determined by operating the opening and closing of the solenoid valve using a power supply (not shown). The liquid to be treated supply unit 22 may be operated in conjunction with a solenoid valve used as, for example, a gas supply unit 21.

[0053] <<Power supply section 23>> The power supply unit 23 supplies power to generate plasma in the discharge gas contained in the plasma generation unit 111. The power supply unit 23 is electrically connected to, for example, a pair of electrodes 112 and supplies power to the pair of electrodes 112, thereby generating plasma in the discharge gas contained in the plasma generation unit 111 via the pair of electrodes 112. For example, a known plasma power supply device is used as the power supply unit 23.

[0054] <<Pressure control unit 24>> The pressure control unit 24 measures the pressure of either the discharge gas and / or the liquid to be processed in the chamber 10, and then controls their pressure or flow rate. For example, the pressure control unit 24 measures the pressure of the discharge gas in the first housing 12 via a pressure sensor 241 provided in the first housing 12, and then adjusts the pressure or flow rate of the discharge gas supplied from the gas supply unit 21 to the first housing 12 via a known gas pressure regulator (not shown). For example, the pressure control unit 24 measures the pressure of the liquid to be processed in the second housing 13 via a pressure sensor 242 provided in the second housing 13, and then adjusts the pressure or flow rate of the liquid to be processed supplied from the liquid to be processed supply unit 22 to the second housing 13 via a known liquid pressure regulator. The pressure control unit 24 may be equipped with a known microcontroller that integrates, for example, a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). In this case, the CPU may read a program stored in ROM, use RAM as a working area to perform calculations based on the measurement information of each pressure sensor 241, 242, and control each pressure regulator by notifying each pressure regulator of an operation command based on the calculation result.

[0055] (An example of the operation of the processing unit 1) Next, an example of the operation of the processing unit 1 will be described.

[0056] The operation of the processing apparatus 1 includes, for example, a gas supply step S11, a liquid to be processed supply step S12, and a plasma processing step S13, as shown in Figure 4.

[0057] The gas supply step S11 and the liquid to be treated supply step S12 may be performed simultaneously, one of them may be performed first, and may be performed multiple times as needed. In this embodiment, an example will be described in which the liquid to be treated supply step S12 is performed after the gas supply step S11, and the plasma treatment step S13 is performed after the liquid to be treated supply step S12.

[0058] <Gas supply step S11> In the gas supply step S11, as shown in FIG. 5 for example, the gas supply unit 21 supplies the discharge gas 120 to the first storage unit 12. After a sufficient amount of the discharge gas 120 for generating plasma for treating the processing liquid 130 to be supplied to the second storage unit 13 in the processing liquid supply step S12 described later is stored in the first storage unit 12, the supply of the discharge gas 120 to the first storage unit 12 may be interrupted, and the supply of the discharge gas 120 to the first storage unit 12 may be resumed as necessary.

[0059] Here, the discharge gas 120 is a gas, and for example, argon, air, nitrogen, oxygen, or helium is used.

[0060] <Processing Liquid Supply Step S12> In the processing liquid supply step S12, the processing liquid supply unit 22 supplies the processing liquid 130 to the second storage unit 13. The processing liquid 130 is a liquid having fluidity. The processing liquid 130 supplied to the second storage unit 13 forms an interface S b (gas-liquid interface) with the discharge gas 120. The processing liquid supply unit 22 supplies the processing liquid 130 to the second storage unit 13 such that, for example, the interface S b is in the vicinity of the boundary surface S a . Here, the interface S b is, for example, concave toward the plasma generation unit 111, and when at least a part of the interface S b contacts the boundary surface S a or extends beyond the boundary surface S a toward the plasma generation unit 111 side, the interface S b is regarded as being located in the vicinity of the boundary surface S a . After a sufficient amount of the processing liquid 130 for processing is stored in the second storage unit 13, the supply of the processing liquid 130 to the second storage unit 13 may be interrupted, and the supply of the processing liquid 130 to the second storage unit 13 may be resumed as necessary.

[0061] Furthermore, by adjusting the supply amounts of the discharge gas 120 and the liquid to be treated 130, the pressure difference between the discharge gas 120 and the liquid to be treated 130 can be adjusted, thereby controlling the interface S between the discharge gas 120 and the liquid to be treated 130. b The position can be adjusted. For example, in a positional relationship where gravity presses the discharge gas 120 against the liquid to be treated 130, it is preferable that the pressure of the discharge gas 120 be adjusted to a range of -2kPa to +4kPa relative to the pressure of the liquid to be treated 130. Also, in a positional relationship where gravity presses the liquid to be treated 130 against the discharge gas 120, it is preferable that the pressure of the liquid to be treated 130 be adjusted to a range of -4kPa to +4kPa relative to the pressure of the discharge gas 120.

[0062] <Plasma treatment step S13> In the plasma processing step S13, the power supply unit 23 supplies power to a pair of electrodes 112, for example as shown in Figure 6(a), to generate plasma 114 in the discharge gas 120 contained in the plasma generation unit 111. In this case, the pair of electrodes 112 provided facing the plasma generation unit 111 can be used to generate plasma 114 that comes into contact with the liquid to be processed 130. The generated plasma 114 causes the interface S b The nearby liquid to be processed 130 is decomposed. In this case, a pair of electrodes 112 provided facing the plasma generation unit 111 are used to decompose the interface S between the liquid to be processed 130 and the discharge gas 120. b Since plasma is generated in the vicinity, the generation of bubbles in the liquid to be treated 130 can be suppressed. This prevents the flow of the liquid to be treated 130 from being obstructed by bubbles, thereby improving the processing efficiency of reducing the molecular weight of the liquid to be treated 130. In this embodiment, the plasma 114 is at the interface S b To explain an example of contact with, in the range affected by plasma 114, plasma 114 is at interface S b It is acceptable to separate them.

[0063] Furthermore, the shorter the distance of the second housing section 13 in the third direction Z, the easier it is for the plasma 114 to reach the liquid to be treated 130, and the easier it is to improve the ratio of the amount treated to the amount of liquid to be treated 130 input. Also, as shown in Figure 6(b), for example, the plasma generation section 111 is large in the XY plane direction perpendicular to the third direction Z (the plane along the first direction X and the second direction Y), i.e., the interface S b The larger the area and the wider the area over which the plasma 114 is generated in the XY plane, the better the ratio of the amount of liquid to be processed to the amount of liquid to be processed 130 that is input can be improved.

[0064] Furthermore, before or during the plasma treatment step S13, the pressure control unit 24 may measure the pressure of either the discharge gas 120 or the liquid to be treated 130, or both, in the chamber 10 via the respective pressure sensors 241 and 242, and then control their pressure or flow rate. That is, the pressure of the discharge gas 120 or the liquid to be treated 130 in the chamber 10 can be adjusted. In this case, the position of the interface between the discharge gas 120 and the liquid to be treated 130 can be adjusted. This makes it possible to further improve the treatment efficiency of the liquid to be treated. As a discharge gas discharge step, the discharge gas 120 is discharged from the gas discharge section 102 provided in the chamber 10 using a discharge pump (not shown) as needed. Also, as a liquid to be treated discharge step, the liquid to be treated is discharged from the liquid to be treated discharge section 104 provided in the chamber 10 using a discharge pump (not shown) as needed to obtain a liquid with reduced molecular weight.

[0065] After performing each of the steps described above, the operation of the processing unit 1 in this embodiment is terminated. Note that the processing unit 1 may, for example, repeat each of the steps described above.

[0066] (Processing device 1, part 1 modification) Next, a first modified example of the processing apparatus 1 will be described. The processing apparatus 1 further comprises a water-impermeable section 115.

[0067] <<Impermeable part 115>> The impermeable portion 115 is provided on the second main surface 11b, for example, as shown in Figures 7(a) to 7(b). The impermeable portion 115 has a lower affinity for the liquid to be treated 130 than the second main surface 11b.

[0068] The shape of the impermeable portion 115 is, for example, sheet-like, as shown in Figure 7(a). In this case, the impermeable portion 115 has holes in at least a portion of the region that overlaps with the plasma generating portion 111, and an interface S is formed at the location of the holes. b A water-impermeable portion 115 is formed. As the material for the water-impermeable portion 115, a material that is hydrophobic or water-repellent to the liquid to be treated 130 is used, for example, a fluoropolymer (fluororesin) is used. Alternatively, the water-impermeable portion 115 may be made of mesh material, as shown in Figure 7(b). In this case, the discharge gas 120 that has entered the mesh of the water-impermeable portion 115 from the plasma generation unit 111 and the liquid to be treated 130 in the second containment unit 13 form an interface S b A formation is created.

[0069] (An example of operation of the first modified form of the processing device 1) Next, an example of the operation of the first modified form of the processing unit 1 will be described.

[0070] <Gas supply step S11> In gas supply step S11, the gas supply unit 21 supplies discharge gas 120 to the first containment unit 12. The discharge gas 120 supplied to the first containment unit 12 is then supplied to the plasma generation unit 111.

[0071] <Step S12: Supply of liquid to be treated> In step S12, the liquid to be treated supply unit 22 supplies the liquid to be treated 130 to the second containment unit 13. The liquid to be treated 130 supplied to the second containment unit 13 is distributed, for example, around the plasma generating unit 111 or at the interface S within the second containment unit 13, as shown in Figure 7(a). aThe liquid flows along the impermeable section 115 provided therein. In this case, the surface tension of the liquid to be treated 130 prevents it from sticking to the dielectric 113. This helps to suppress a decrease in the processing efficiency of the liquid to be treated 130.

[0072] (Second modified example of processing device 1) Next, a second modified example of the processing unit 1 will be described.

[0073] <<Separation mechanism 11>> The separation mechanism 11 includes, for example, as shown in Figure 8, a separation mechanism 11-1 having a plasma generating unit 111-1, a pair of electrodes 112-1, and a dielectric 113-1, and a separation mechanism 11-2 having a plasma generating unit 111-2, a pair of electrodes 112-2, and a dielectric 113-2.

[0074] The separation mechanism 11-1 has a first main surface 11f-1 facing the first housing section 12-1 and a second main surface 11b-1 facing the second housing section 13. The separation mechanism 11-1 has a plasma generating section 111-1 that penetrates the first main surface 11f-1 and the second main surface 11b-1 and connects the first housing section 12-1 and the second housing section 13. Of the plasma generating section 111-1, the interface surface S a -1 is an opening on the same plane as the second main surface 11b-1, and indicates the boundary between the plasma generation section 111-1 and the second housing section 13. Boundary surface S a -1 can be, for example, the interface between the discharge gas contained in the plasma generation unit 111-1 and the liquid to be processed contained in the second containment unit 13.

[0075] The separation mechanism 11-2 has a first main surface 11f-2 facing the first housing section 12-2 and a second main surface 11b-2 facing the second housing section 13. The separation mechanism 11-2 has a plasma generating section 111-2 that penetrates the first main surface 11f-2 and the second main surface 11b-2 and connects the first housing section 12-2 and the second housing section 13. Of the plasma generating section 111-2, the interface surface S a -2 is an opening on the same plane as the second main surface 11b-2 and indicates the boundary between the plasma generation section 111-2 and the second housing section 13. Boundary surface S a-2 can be, for example, the interface between the discharge gas contained in the plasma generation unit 111-2 and the liquid to be processed contained in the second containment unit 13.

[0076] (An example of operation of the second modified version of the processing unit 1) Next, an example of the operation of the second modified form of the processing unit 1 will be described.

[0077] <Plasma treatment step S13> The liquid to be processed 130 contained in the second containment section 13 is processed by plasma 114-1 generated by one pair of electrodes 112-1 in the plasma generation section 111-1, and by another plasma 114-2 generated by the other pair of electrodes 112-2 in the plasma generation section 111-2, as shown in Figure 8, for example. That is, multiple plasma generation sections 111 are provided in the flow direction of the liquid to be processed 130 from the liquid to be processed introduction section 103 to the liquid to be processed discharge section 104. In this case, the liquid to be processed 130 contained in the second containment section 13 is processed by multiple plasmas 114-1 and 114-2 generated by the plasma generation sections 111 (111-1 and 111-2). This makes it possible to further improve the processing efficiency of the liquid to be processed 130.

[0078] Figure 9(a) is a schematic cross-sectional view showing an example of a CC cross-section of the processing apparatus 1 shown in Figure 8. The separation mechanism 11 is composed of a plurality of plate-shaped dielectrics 113-1, 113-2 and a plurality of plate-shaped pairs of electrodes 112-1 (one electrode 112-1a and the other electrode 112-1b) and 112-2 (one electrode 112-2a and the other electrode 112-2b), as shown in Figure 9(a), for example.

[0079] Furthermore, the processing apparatus 1 may also include, for example, a first housing section 12, a plurality of separation mechanisms 11-1, 11-2, and a plurality of second housing sections 13-1, 13-2, as shown in Figure 9(b). In this case, multiple plasmas 114-1, 114-2 can be generated using a discharge gas 120 housed in one first housing section 12, and multiple liquids to be processed 130-1, 130-2 can be processed. That is, by sharing the discharge gas 120 for generating multiple plasmas 114-1, 114-2, the amount of discharge gas used can be reduced, or the utilization efficiency of the discharge gas can be improved.

[0080] Furthermore, the processing apparatus 1 may be composed of a single curved dielectric 113, where each dielectric 113-1 and 113-2 in Figure 8 is made up of a single curved dielectric 113, and each pair of electrodes 112-1 and 112-2 in Figure 8 is made up of a single curved pair of electrodes 112 (one electrode 112a and the other electrode 112b). Alternatively, the processing apparatus 1 may be composed of a single cylindrical dielectric 113, where each dielectric 113-1 and 113-2 in Figure 8 is made up of a single cylindrical dielectric 113, and each pair of electrodes 112-1 and 112-2 in Figure 8 is made up of a single cylindrical pair of electrodes 112 (one electrode 112a and the other electrode 112b). In this case, the separation mechanism 11 may be manufactured by forming plasma generating sections 111 at predetermined intervals in a five-layer separation mechanism 11 including the dielectric 113 and the pair of electrodes 112, and then molding it into a cylindrical shape. In this case, plasma generating units 111 can be provided in the circumferential direction (the figure illustrates a case where four plasma generating units 111-1 and 111-2 are formed in the circumferential direction), and more plasma 114 can be generated compared to a plate-shaped separation mechanism 11. This makes it possible to further improve the processing efficiency of the liquid to be processed 130. In addition, the cylindrically molded separation mechanism 11 can replace at least a part of the existing fluid piping. For this reason, for example, when introducing equipment to reduce the molecular weight of high-molecular-weight organic compounds in a food manufacturing plant, the introduction cost can be reduced by effectively utilizing at least a part of the existing piping.

[0081] (Third modified example of processing device 1) Next, a third modified example of the processing apparatus 1 will be described. The processing apparatus 1 has a pair of electrodes 112, one electrode 112a and the other electrode 112b, which are arranged facing each other with a plasma generating unit 111 in between, as shown in Figure 10, for example.

[0082] <<Pair of electrodes 112>> As shown in Figure 10, for example, the pair of electrodes 112 are arranged such that one electrode 112a and the other electrode 112b face each other across the plasma generation unit 111, and the distance between them and the second housing unit 13 is smaller than the distance between them and the first housing unit 12. The distance between one electrode 112a and the other electrode 112b is determined based on the Paschen curve. In this embodiment, the electrode distance at which the Paschen curve is minimized is preferred. However, if the arrangement or ease of processing of each electrode 112a, 112b is prioritized, the electrodes 112a, 112b may be arranged or processed at a wider distance than the electrode distance at which the Paschen curve is minimized, and plasma may be generated by adjusting the applied voltage. Specifically, the distance between one electrode 112a and the other electrode 112b is, for example, 1 μm to 5 mm. Furthermore, when discharging into argon gas at a constant pressure, the closer the electrode distance is to approximately 8 μm, which is when the Paschen curve is minimized, the more preferable it is. Therefore, the dimensions of the plasma generation unit 111 are preferably set to a value close to approximately 8 μm, for example, 1 μm to 5 mm, depending on the distance between one electrode 112a and the other electrode 112b, and especially when argon gas is used.

[0083] (An example of operation of the third modified form of the processing device 1) Next, an example of the operation of the third modified form of the processing unit 1 will be described.

[0084] <Plasma treatment step S13> In the plasma processing step S13, the power supply unit 23 supplies power to a pair of electrodes 112, for example as shown in Figure 11, and generates plasma 114 in the discharge gas 120 contained in the plasma generation unit 111. The plasma 114 causes the interface S bThe nearby liquid to be processed 130 is decomposed. At this time, the pair of electrodes 112 are positioned opposite each other in the direction in which the first housing portion 12 and the second housing portion 13 face each other, i.e., along the third direction Z, compared to when the electrodes are positioned opposite each other along the third direction Z, the plasma 114 is directed towards the interface S b It can be generated in a more nearby location. The power supply unit 23 may generate the plasma 114 continuously or intermittently by supplying power to the pair of electrodes 112.

[0085] (An example of operation of the fourth modified form of the processing device 1) Next, an example of the operation of a fourth modified example of the processing apparatus 1 will be described. The discharge gas 120 in the first containment section 12 and the liquid to be processed 130 in the second containment section 13 continue to flow.

[0086] <Gas supply step S11> In the gas supply step S11, the gas supply unit 21 continues to supply the discharge gas 120 in subsequent steps, for example, as shown in Figure 12(a), so that the discharge gas 120 continues to flow in the first containment unit 12. If the gas discharge unit 102 and the gas introduction unit 101 of the chamber 10 are connected directly or indirectly via a storage tank or the like, and the discharge gas 120 circulates, the gas supply unit 21 may supply the discharge gas 120 to the first containment unit 12 in an amount equal to the amount consumed by the processing device 1.

[0087] The discharge gas 120 flows along the first direction X, as shown by the solid arrow in Figure 12(a), from the left to the right of the first containment section 12, and a portion of it is supplied to the plasma generation section 111.

[0088] <Step S12: Supply of liquid to be treated> In step S12, the liquid to be treated supply unit 22 continues to supply the liquid to be treated 130 in subsequent steps, for example, so that the liquid to be treated 130 in the second containment unit 13 continues to flow. If the liquid to be treated discharge unit 104 and the liquid to be treated introduction unit 103 of the chamber 10 are connected directly or indirectly via a storage tank or the like, and the liquid to be treated 130 circulates, the liquid to be treated supply unit 22 may supply the liquid to be treated 130 from the liquid to be treated supply unit 22 to the second containment unit 13 in the amount consumed by the processing device 1. In this case, the liquid to be treated 130 flowing through the second containment unit 13 can be processed continuously or intermittently. This makes it possible to further improve the processing efficiency of the liquid to be treated 130.

[0089] The liquid to be treated 130 flows from the left side to the right side of the second containment section 13 along the first direction X, as shown by the arrow in Figure 12(a), for example.

[0090] <Plasma treatment step S13> In the plasma processing step S13, the power supply unit 23 supplies power to a pair of electrodes 112, for example as shown in Figure 12(a), and generates plasma 114 in the discharge gas 120 supplied to the plasma generation unit 111. The plasma 114 causes the interface S b The nearby liquid to be processed 130 is decomposed. The discharge gas 120 that was not consumed for the generation of plasma 114 flows out of the plasma generation unit 111, is introduced into the first containment unit 12, and is then discharged from the right side of the first containment unit 12. At this time, after the discharge gas 120 has been consumed for the generation of plasma 114, new discharge gas 120 is quickly supplied to the space where plasma 114 is generated, and the discharge gas 120 in the plasma generation unit 111 can be made uniform. In this case, plasma 114 can be stably generated in the plasma generation unit 111. This makes it possible to suppress a decrease in the processing efficiency of the liquid to be processed 130.

[0091] (Modified example of processing device 1) Next, a fifth modified example of the processing apparatus 1 will be described.

[0092] <<Separation mechanism 11>> The separation mechanism 11 includes a plasma generating unit 111-1 and a plasma generating unit 111-2, as shown in Figure 12(b), for example.

[0093] The plasma generation section 111-1 penetrates the first main surface 11f and the second main surface 11b, connecting the first housing section 12 and the second housing section 13. Of the plasma generation section 111-1, the interface surface S a -1 is an opening on the same plane as the second main surface 11b, and indicates the boundary between the plasma generation section 111-1 and the second housing section 13. Boundary surface S a -1 can be, for example, the interface between the discharge gas contained in the plasma generation unit 111-1 and the liquid to be processed contained in the second containment unit 13.

[0094] The plasma generation section 111-2 has a first main surface 11f and a second main surface 11b that penetrate from the plasma generation section 111-1, connecting the first housing section 12 and the second housing section 13. Of the plasma generation section 111-2, the interface surface S a -2 is an opening coplanar with the second main surface 11b, i.e., an opening coplanar with the plasma generation section 111-1, and indicates the boundary between the plasma generation section 111-2 and the second housing section 13. Boundary surface S a -2 can be, for example, the interface between the discharge gas contained in the plasma generation unit 111-2 and the liquid to be processed contained in the second containment unit 13.

[0095] (An example of operation of the fifth modified form of the processing device 1) Next, an example of the operation of the fifth modified form of the processing unit 1 will be described.

[0096] <Gas supply step S11> In the gas supply step S11, the gas supply unit 21 flows along the first direction X, for example, as shown by the solid arrow in Figure 12(b), from the left side (gas inlet 101 side) to the right side (gas outlet 102 side) of the first containment unit 12, and a portion of it is supplied to the plasma generation unit 111-1 and the plasma generation unit 111-2.

[0097] <Step S12: Supply of liquid to be treated> In step S12, the liquid to be treated supply unit 22 adjusts the flow rate of the liquid to be treated 130 that flows from the liquid to be treated introduction unit 103 to the liquid to be treated discharge unit 104.

[0098] The liquid to be treated 130 flows along the first direction X, for example, as shown by the arrow in Figure 12(b), from the left side (liquid to be treated introduction section 103 side) to the right side (liquid to be treated discharge section 104 side) of the second containment section 13.

[0099] <Plasma treatment step S13> In the plasma processing step S13, the power supply unit 23 supplies power to, for example, a pair of electrodes 112-1 and generates plasma 114-1 in the discharge gas 120 supplied to the plasma generation unit 111-1. The plasma 114-1 causes the interface S b -1 The liquid to be processed 130 near -1 is decomposed. The power supply unit 23 also supplies power to, for example, a pair of electrodes 112-2, and generates plasma 114-2 in the discharge gas 120 supplied to the plasma generation unit 111-2. The plasma 114-2 causes the interface S b -2 The liquid to be treated 130 in the vicinity is decomposed. In this case, the liquid to be treated 130 is treated with one plasma 114-1 generated by one pair of electrodes 112-1, and then treated with another plasma 114-2 generated by the other pair of electrodes 112-2. This makes it possible to further improve the processing efficiency of the liquid to be treated 130.

[0100] The multiple plasma generating units 111-1 and 111-2 may be provided along the direction in which the liquid to be processed 130 flows, or they may be provided in a direction other than the direction in which the liquid to be processed 130 flows. For example, multiple units may be provided along the second direction Y. In this case, more liquid to be processed 130 can be processed compared to when a single plasma 114 is used. This improves the processing efficiency of the liquid to be processed 130.

[0101] Furthermore, the direction in which the discharge gas 120 flows and the direction in which the liquid to be treated 130 flows do not necessarily have to be the same; they may be in different directions.

[0102] According to this embodiment, the chamber 10 has a plasma generating unit 111 connecting the first housing section 12 and the second housing section 13. Furthermore, a pair of electrodes 112 are provided facing the plasma generating unit 111. That is, the liquid surface of the liquid to be processed 130 housed in the second housing section 13 and the discharge gas 120 in the plasma generating unit 111 form an interface S b Therefore, a pair of electrodes 112 provided facing the plasma generation unit 111 are used to form the interface S between the liquid to be processed 130 and the discharge gas 120. b Since plasma 114 is generated nearby, the generation of bubbles in the liquid to be treated 130 can be suppressed. This prevents the flow of the liquid to be treated 130 from being obstructed by bubbles, thereby improving the processing efficiency of reducing the molecular weight of the liquid to be treated 130.

[0103] Furthermore, according to this embodiment, the processing apparatus 1 includes a dielectric 113 provided on the surface of a pair of electrodes 112. This prevents foreign matter generated by electrode wear during plasma generation from being mixed into the liquid to be processed 130. This improves the processing quality by reducing the molecular weight of the liquid to be processed 130.

[0104] Furthermore, according to this embodiment, the processing apparatus 1 is further equipped with a pressure sensor 241 (242) for measuring pressure in at least one of the first housing section 12 or the second housing section 13. That is, the pressure of the discharge gas 120 or the liquid to be processed 130 in the chamber 10 can be adjusted. For this purpose, the interface S between the discharge gas 120 and the liquid to be processed 130 b The position of the component can be adjusted. This allows for further improvement in the processing efficiency of reducing the molecular weight of the liquid to be treated 130.

[0105] Furthermore, according to this embodiment, the impermeable portion 115 is provided on the main surface of the separation mechanism 11 on the side of the second housing portion 13 (second main surface 11b), and its affinity for the liquid to be treated 130 is lower than that of the main surface (second main surface 11b). Therefore, the surface tension of the liquid to be treated 130 prevents it from sticking to the dielectric 113. This makes it possible to suppress the decrease in processing efficiency when the liquid to be treated 130 is reduced in molecular weight.

[0106] Furthermore, according to this embodiment, multiple plasma generation units 111 are provided in the flow direction of the liquid to be treated 130 from the liquid to be treated introduction unit 103 to the liquid to be treated discharge unit 104. As a result, the liquid to be treated 130 contained in the second containment unit 13 is treated by multiple plasmas 114 generated in the plasma generation units 111. This makes it possible to further improve the processing efficiency in reducing the molecular weight of the liquid to be treated 130.

[0107] Furthermore, according to this embodiment, the pair of electrodes 112 are arranged spaced apart in the direction from the first housing section 12 toward the second housing section 13. Therefore, plasma 114 can be generated regardless of the shape of the plasma generation section 111. This makes it possible to improve the power consumption efficiency used in the process of reducing the molecular weight of the liquid to be processed 130.

[0108] Furthermore, according to this embodiment, the system includes a gas supply step S11 in which a discharge gas 120 is supplied to the plasma generation unit 111, a liquid to be processed supply step S12 in which a liquid to be processed 130 is supplied to the second containment unit 13, and a plasma processing step S13 in which a plasma 114 is generated in the discharge gas 120 supplied to the plasma generation unit 111 using a pair of electrodes 112 that are provided facing the plasma generation unit 111 and have a dielectric 113 on their surface, and the liquid to be processed 130 supplied to the second containment unit 13 is processed. That is, the liquid surface of the liquid to be processed 130 contained in the second containment unit 13 and the discharge gas 120 in the plasma generation unit 111 are at an interface S b Therefore, a pair of electrodes 112 provided facing the plasma generation unit 111 are used to form the interface S between the liquid to be processed 130 and the discharge gas 120. bSince plasma 114 is generated nearby, the generation of bubbles in the liquid to be treated 130 can be suppressed. This prevents the flow of the liquid to be treated 130 from being obstructed by bubbles, thereby improving the processing efficiency of reducing the molecular weight of the liquid to be treated 130. [Examples]

[0109] The following describes experimental results regarding the effects of the processing apparatus 1 when using the embodiment described above. In this experiment, molecular weight distributions were created when the liquid to be treated 130 was plasma-treated for a predetermined time in both a comparative example using conventional plasma treatment technology (point type) and an example of the present invention using the plasma treatment technology of the present invention. By comparing these distributions, the difference in the effect of reducing the molecular weight of the liquid to be treated 130 was confirmed.

[0110] First, let me explain the conditions of this experiment.

[0111] In the example of the present invention, argon gas was used as the discharge gas 120. In the comparative example and the example of the present invention, fucoidan (Fucoidan-Laminaria japonica YF01606) manufactured by BioSynth was used as the treatment solution 130. The method for preparing the treatment solution 130 was to dissolve powdered fucoidan in deionized water. The concentration of the treatment solution 130 was 1 mg / mL.

[0112] For evaluating the molecular weight distribution, Gel Permeation Chromatography (GPC) was performed using "Nexera®" manufactured by Shimadzu Corporation (registered trademark). The column used for GPC was "OHpak SB-806M HQ" from the SHODEX® series manufactured by ResonaC Corporation (registered trademark). The column temperature was set to 40°C. A 0.1 M (molar concentration) aqueous sodium nitrate solution was used as the mobile phase. The mobile phase flow rate was 1 mL / min.

[0113] Next, the apparatuses of the comparative example and the present invention will be described. As the apparatus of the comparative example, a liquid-immersion plasma apparatus that generates a point-type (0-dimensional) plasma between electrodes was used, as shown in Figure 13. Note that this liquid-immersion plasma apparatus does not require the use of a gas equivalent to the discharge gas 120. The part corresponding to the separation mechanism 11 consists of electrodes corresponding to a pair of electrodes 112 (the pair of electrodes of the comparative example) and an insulating sleeve made of alumina that covers a part of the surface of the pair of electrodes of the comparative example. The tips of the pair of electrodes of the comparative example that face the part corresponding to the plasma generation section 111 (the plasma generation section of the comparative example) are exposed in the plasma generation section of the comparative example. The insulating sleeve is arranged with a distance of about 2 mm along the first direction X. The exposed parts of the pair of electrodes of the comparative example are arranged with a distance of about 1 mm along the first direction X. The pair of electrodes of the comparative example were made of tungsten facing each other. The liquid-immersion plasma apparatus can accommodate 100 mL of the liquid to be treated 130. The volume of the liquid to be treated 130 by the liquid-immersion plasma apparatus is 100 mL.

[0114] In the comparative example, a bipolar pulse power supply was used as the power supply corresponding to the power supply unit 23 (the power supply of the comparative example). Specifically, the output voltage of an inverter using a semiconductor switch was boosted by an inductor (coil) and used. The waveforms of voltage and current when power is supplied by the power supply of the comparative example are shown in Figures 14(a) to 14(b). In particular, the voltage does not become a square wave because an inductor is used. Other conditions were set to typical conditions for stable generation of liquid plasma, with an amplitude of 400V, a frequency of 30kHz, a duty cycle of 3% for positive pulses (pulse waves greater than 0 in the waveform), and a duty cycle of 3% for negative pulses (pulse waves less than 0 in the waveform). The waveform of power when power is supplied by the power supply of the comparative example was calculated from the product of the voltage waveform and the current waveform, and as shown in Figure 14(c), one period is 33.3 × 10⁻⁶. -6 The average power per second, or per cycle, is 12.8W.

[0115] As the processing apparatus 1 of the present invention example, the apparatus with the configuration shown in Figures 1, 2, and 6(b) was used. The plasma generation section 111 is provided with multiple circular holes in a cross section perpendicular to the third direction Z, as shown in Figure 2, and the diameter of each hole is 1 mm. The separation mechanism 11 is made of alumina (ceramics) with a height of 1 mm along the third direction Z. The second main surface b is processed with PTFE (polytetrafluoroethylene) with a thickness of 0.5 mm. Both electrodes 112 are made of copper, and the distance between each electrode 112a and 112b is 0.4 mm. As shown in Figure 2, the pair of electrodes 112 have a circular cross section with a diameter of 4 cm perpendicular to the third direction Z. The distance between the pair of electrodes 112 and each housing section 12 and 13 is 0.3 mm to 0.4 mm. The second housing section 13 has a height of 2.5 mm along the third direction Z, and its cross-section perpendicular to the third direction Z is a circle with a diameter of 3 cm, matching the area on which the plasma generation section 111 can be provided for the pair of electrodes 112. The volume of the liquid to be treated 130 that is plasma-treated by the processing apparatus 1 corresponds to the volume of the second housing section 13, that is, the volume of the cylindrical liquid to be treated 130 with a diameter of 3 cm and a height of 2.5 mm, which is approximately 1.767 mL.

[0116] In this example of the present invention, a bipolar pulse power supply was used as the power supply unit 23. Specifically, the output voltage of an inverter using a semiconductor switch was used directly without an inductor. The waveforms of voltage and current when power is supplied by the power supply unit 23 are shown in Figures 15(a) to 15(b). In particular, the voltage is a square wave because no inductor is used. Other conditions differ from those of the comparative example, with an amplitude of 2.7kV, a frequency of 10kHz, a duty cycle of 6% for both positive and negative pulses. Furthermore, the waveform of power when power is supplied by the power supply unit 23 is calculated from the product of the voltage waveform and the current waveform, and as shown in Figure 15(c), one period is 100 × 10⁻⁶. -6 The average power per second, or per cycle, is 1.7W.

[0117] Next, the molecular weight distributions of the comparative example and the present invention example will be explained based on the results of this experiment. The results of this experiment are shown in Figures 16(a) and 16(b). In the graphs of Figures 16(a) and 16(b), the horizontal axis shows the logarithmic scale of Molecular Weight, and the vertical axis shows Differential Molecular Weight. Specifically, the values ​​on the vertical axis represent the relative proportion of each molecular weight to the total amount of molecules in the treated liquid 130. Furthermore, each curve shows the molecular weight distribution for each processing time during plasma treatment, with "0 min" showing the molecular weight distribution for 0 minutes of processing time, "1 min" showing the molecular weight distribution for 1 minute of processing time, "3 min" showing the molecular weight distribution for 3 minutes of processing time, "5 min" showing the molecular weight distribution for 5 minutes of processing time, "10 min" showing the molecular weight distribution for 10 minutes of processing time, "20 min" showing the molecular weight distribution for 20 minutes of processing time, and "30 min" showing the molecular weight distribution for 30 minutes of processing time. For example, the molecular weight corresponding to the highest point on the curve indicates the molecular weight that is most abundant in the treated liquid 130 during that processing time. In the following explanation, the portion of the molecular weight distribution where the height along the vertical axis is maximum is called a peak, and the height of the value along the vertical axis of the peak is called the peak intensity.

[0118] As shown in Figure 16(a), the molecular weight distribution in the treated liquid 130 after plasma treatment using the comparative apparatus is as follows: at treatment times of 0 minutes and 5 minutes, there is only one peak in the molecular weight distribution, and its molecular weight is 10. 6 It is almost unchanged from the Da stage. The molecular weight distribution after a processing time of 30 minutes shows that the molecular weight of the peak is 10. 6 10 from Da platform 5 It has shifted to the upper end of the Da range, and a slight reduction in molecular weight has occurred, but the molecular weight is 10 2 ~10 3 No Da-type molecules have been generated.

[0119] As shown in Figure 16(b), the molecular weight distribution in the treated liquid 130 after plasma treatment by the apparatus 1 of the present invention is such that the peak molecular weight at 1 minute of processing time is 10. 5 As the Da period shifts to the latter half, a new peak appears at molecular weight 10 3It appears in the low molecular weight region of the Da range. Furthermore, after 1 minute of processing time, molecular weight 10 2 ~10 3 The peak intensity of the Da group increased, and at a processing time of 5 minutes, the molecular weight was 10. 3 The peak intensity of the Da stage is 10 5 ~10 6 The peak intensity is higher than that of the Da range.

[0120] Next, a comparison of the molecular weight distribution between the comparative example and the present invention example will be described. In comparing the molecular weight distribution, the molecular weight distribution under the same volume of liquid to be treated and the same energy consumption (=electrical energy = power × time) will be compared to confirm the differences between the two examples. For comparison conditions, the volume of liquid to be treated will be assumed to be 100 mL and the energy consumption to be 6.4 Wh.

[0121] For the comparative example, since the processing volume of liquid 130 is 100 mL, no conversion regarding processing volume is necessary. The processing time corresponding to an energy consumption of 6.4 Wh is calculated using an average power of 12.8 W as 6.4 Wh / 12.8 W = 0.5 hours = 30 minutes. Therefore, the comparative example was compared to the molecular weight distribution at a processing time of 30 minutes.

[0122] In the present invention example, when the processing volume of the liquid to be treated 130 is converted to 100 mL, it corresponds to approximately 56.6 treatments of the volume of the second storage section 13, which is 1.767 mL. Therefore, the energy consumption required to process 100 mL of the liquid to be treated 130 is 1.7 W average power × 56.6 times = approximately 96.2 W. At this time, the processing time corresponding to an energy consumption of 6.4 Wh is calculated using the average power of 96.2 W as 6.4 Wh / 96.2 W = approximately 0.0665 hours = 3.99 minutes = approximately 4 minutes. Therefore, the comparison target for the present invention example is the molecular weight distribution intermediate between processing times of 3 minutes and 5 minutes.

[0123] Based on the above calculation results, when comparing the molecular weight distribution of the comparative example after a processing time of 30 minutes with the molecular weight distribution assumed to be between the processing times of 3 minutes and 5 minutes in the present invention example, the molecular weight distribution of the comparative example was 10 5While only one peak in the Da range appears, in the molecular weight distribution of the present invention example, the peak intensity of the molecular weight 10 is weakened. 5 In addition to the Da peak, molecular weight 10 3 A peak in the Da range is observed. In other words, the molecular weight distribution of the present invention example is clearly lower in molecular weight compared to the molecular weight distribution of the comparative example. For this reason, it can be said that the processing apparatus 1 of the present invention has improved processing efficiency in reducing the molecular weight of the liquid to be treated 130 compared to the processing apparatus of the comparative example.

[0124] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0125] 1 Processing Unit 10 Chambers 101 Gas Inlet 102 Gas discharge section 103 Liquid to be treated introduction section 104 Processed liquid discharge section 11 Separation mechanism 11f First Main Surface 11b 2nd principal surface 111 Plasma generation unit 112 Pair of electrodes 113 Dielectric 114 Plasma 115 Impermeable area 12. First Detention Unit 13. Second Detention Unit 21 Gas Supply Department 22. Liquid to be processed supply unit 23 Power supply section 24 Pressure Control Unit S11 Gas supply step S12 Step to supply the liquid to be treated S13 Plasma treatment step Q Processing space S a interface S b Interface (air-liquid interface)

Claims

1. A processing apparatus that processes a liquid to be processed by generating plasma in a discharge gas, Chamber and, A pair of electrodes for generating the aforementioned plasma, A dielectric material provided on the surface of the pair of electrodes, Equipped with, The aforementioned chamber is A first containment section in which the discharge gas is contained, A second storage section in which the liquid to be processed is contained, A plasma generating unit connecting the first housing section and the second housing section, It has, The pair of electrodes are provided facing the plasma generation unit. A processing device characterized by the following.

2. The first or second housing is further provided with a pressure sensor for measuring pressure. The apparatus according to claim 1, characterized in that

3. A separation mechanism provided between the first housing section and the second housing section, An impermeable portion is provided on the main surface of the separation mechanism on the side of the second housing portion, and has a lower affinity for the liquid to be treated than the main surface, To be even more prepared The apparatus according to claim 1 or claim 2, characterized by the following:

4. The chamber further includes a liquid to be treated introduction section for introducing the liquid to be treated into the second containment section, and a liquid to be treated discharge section for discharging the liquid to be treated from the second containment section. Multiple plasma generating units are provided in the flow direction of the liquid to be treated, from the liquid to be treated introduction section to the liquid to be treated discharge section. The apparatus according to claim 1 or claim 2, characterized by the following:

5. The pair of electrodes are arranged so as to be spaced apart in the direction from the first housing to the second housing. The apparatus according to claim 1 or claim 2, characterized by the following:

6. A processing method for treating a liquid to be processed by generating plasma in a discharge gas, A gas supply step involves supplying the discharge gas to a plasma generating section that connects a first containment section in which the discharge gas is contained and a second containment section in which the liquid to be processed is contained within the chamber. A step of supplying the liquid to be treated to the second housing, The system comprises a plasma processing step in which a pair of electrodes, each having a dielectric surface and positioned toward the plasma generating unit, are used to generate the plasma in the discharge gas supplied to the plasma generating unit in the gas supply step, thereby processing the liquid to be processed supplied in the liquid to be processed supply step. A processing method characterized by the following.

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