JP2011121900A - Treatment apparatus for harmful substance-containing liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treatment apparatus for a harmful substance-containing liquid that removes harmful substances in a liquid. <P>SOLUTION: The treatment apparatus 1 for a harmful substance-containing liquid includes a reservoir tank 2 for a liquid to be treated, a first treatment part 3, a second treatment part 4 and a treated liquid recovery tank 5. The reservoir tank 2 for a liquid to be treated reserves a liquid to be treated that contains a harmful substance. In the first treatment part 3, a predetermined gas is supplied under pressure to a liquid fed from the reservoir tank 2 for a liquid to be treated to cause the liquid to contain fine bubbles having a diameter of 50 μm or less. In the second treatment part 4, a non-equilibrium plasma is generated by discharge, and the liquid containing fine bubbles fed from the first treatment part 3 is treated with the plasma. In the treated liquid recovery tank 5, a liquid treated in the second treatment part 4 is recovered. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a processing apparatus for processing a liquid containing harmful substances.

  Conventionally, processing apparatuses for processing liquids containing harmful substances are known. As a liquid containing a harmful substance insoluble in water, an insulating oil containing polychlorinated biphenyl (abbreviated as PCB) can be given. Polychlorinated biphenyls are highly toxic, stable and difficult to decompose, so that they are difficult to treat as waste and are prohibited from being produced and used as one of the environmental pollutants.

  Typical methods for conventional polychlorinated biphenyl treatment include chemical treatment and photolysis technology by dechlorination using metallic sodium and alkali, and actual treatment and various levels of actual test data have been published. Yes. There is also a polychlorinated biphenyl treatment technology based on adsorption purification (see, for example, Patent Document 1).

  In addition, liquid infectious wastes such as human waste, body fluids, blood, etc., which are generated in medical institutions by artificial dialysis, surgery or inspection, are liquids containing water-soluble harmful substances. It must be disposed of safely after being treated (see, for example, Patent Document 2).

JP 11-319403 A JP 2001-000982 A

  In order to process liquids containing these harmful substances, a large-scale treatment facility that takes into account the effects of harmful substances on the surrounding environment is required. In particular, PCB-containing waste must be processed at the responsibility of the storage company, and must be handled by the storage company itself or a specialized processing company. In addition, the cost for storage and processing of PCB-containing waste is enormous, which is a heavy burden on storage companies.

  An object of the present invention is to provide a hazardous substance-containing liquid processing apparatus capable of removing harmful substances in a liquid.

The present invention includes a liquid storage section for storing a liquid to be processed containing a harmful substance,
A first processing unit for supplying a predetermined gas under pressure to the liquid supplied from the liquid storage unit and containing fine bubbles;
A second processing unit that generates non-equilibrium plasma by discharge and processes a liquid containing fine bubbles supplied from the first processing unit;
A toxic substance-containing liquid processing apparatus comprising: a liquid recovery unit that recovers the liquid processed by the second processing unit.

In the present invention, the second processing unit includes:
Linear discharge electrodes extending vertically;
A ground electrode extending vertically opposite the discharge electrode;
A power supply device for supplying power for generating non-equilibrium plasma to the discharge electrode;
A first liquid supply unit provided on the ground electrode and configured to supply the liquid supplied from the first processing unit to a surface of the ground electrode facing the discharge electrode;
A first liquid is provided below the ground electrode, flows down on the surface of the ground electrode facing the discharge electrode, receives liquid processed by non-equilibrium plasma, and supplies the processed liquid to the liquid recovery section. Two liquid supply units;
It is characterized by including.

  In the present invention, the surface of the ground electrode facing the discharge electrode is subjected to a roughening treatment.

  In the present invention, the predetermined gas is an inert gas, and the liquid to be treated is an insulating oil containing polychlorinated biphenyl.

  In the present invention, the predetermined gas is pure oxygen, and the liquid to be treated is an insulating oil containing polychlorinated biphenyl.

  In the present invention, the predetermined gas is ozone, and the liquid to be treated is a liquid infectious waste containing a water-soluble harmful substance.

  According to the present invention, the liquid to be processed containing the harmful substance stored in the liquid storage unit is supplied to the first processing unit. In the first processing unit, a predetermined gas is supplied under pressure to the liquid supplied from the liquid storage unit to contain fine bubbles, for example, microbubbles having a diameter of 50 μm or less. Thereby, the conductivity of the liquid containing fine bubbles is improved as compared with that before the treatment.

The liquid containing fine bubbles in the first processing unit is supplied to the second processing unit. In the second processing unit, the internal air is ionized into electrons and ions by discharge, and the electron temperature and the ion temperature are thermodynamically balanced while the electron temperature of the electrons is higher than the ion temperature of the ions. A non-equilibrium plasma is generated which is a plasma in a non-state. In the second processing unit, high-speed electrons can be obtained in a state where the temperature of the non-equilibrium plasma is kept at room temperature. This high-speed electron collides with various molecules in the air, and generates chemically active species rich in reactivity, such as radicals, excited molecules, and ions. Most of the harmful components contained in the liquid are decomposed and removed by a chemical reaction by chemically active species together with high-speed electron collision. The fine bubbles contained in the liquid are negatively charged, and when the fine bubbles disappear, the temperature inside the bubbles becomes high and the pressure becomes high. When the microbubbles are negatively charged, harmful components are attracted, and the high-temperature and high-pressure conditions that occur when the microbubbles are extinguished breaks down the gas that forms the bubbles, generating powerful radicals. Harmful components are removed by radicals. In this way, the liquid containing fine bubbles supplied from the first processing unit is processed.
The liquid from which harmful substances have been decomposed and removed by the second processing unit is recovered by the liquid recovery unit.

  Thus, since the fine bubbles are contained in the liquid containing the harmful substance in the first processing unit, the conductivity of the liquid is improved, and even if the liquid containing the fine bubbles is supplied to the second processing unit, Discharge can be stably performed in the second processing unit, and non-equilibrium plasma can be stably generated. Due to the synergistic effect of decomposing and removing harmful substances by non-equilibrium plasma and decomposing and removing detrimental substances generated when microbubbles disappear, efficient use of harmful substances in the liquid is possible with equipment that has at least a first processing section and a second processing section. Can be removed well.

  According to the invention, the second processing section includes a linear discharge electrode extending vertically, a ground electrode, a power supply device, a first liquid supply section, and a second liquid supply section. The ground electrode extends vertically to face the discharge electrode. The power supply device supplies power for generating non-equilibrium plasma to the discharge electrode. The first liquid supply unit is provided above the ground electrode, and supplies the liquid supplied from the first processing unit to a surface of the ground electrode facing the discharge electrode. The second liquid supply unit is provided below the ground electrode, flows down on the surface of the ground electrode facing the discharge electrode, receives the liquid processed in the non-equilibrium plasma atmosphere, and is processed by the liquid recovery unit. Supply liquid.

  The liquid containing fine bubbles is supplied by the first liquid supply unit onto the surface of the ground electrode that faces the discharge electrode, flows down on the surface of the ground electrode that faces the discharge electrode, and is received by the second liquid supply unit. . The surface of the earth electrode facing the discharge electrode is wet with a liquid containing fine bubbles. Since the fine bubbles are contained in the liquid, the conductivity of the liquid is improved, and even if the liquid exists on the surface of the ground electrode facing the discharge electrode, the discharge can be performed stably. Therefore, the harmful substance in the liquid can be removed by passing the liquid containing the harmful substance containing fine bubbles through the non-equilibrium plasma atmosphere formed between the discharge electrode and the ground electrode.

  Furthermore, according to the present invention, the surface of the ground electrode facing the discharge electrode is subjected to a roughening treatment. As a result, the liquid to be treated can be made to flow uniformly over the entire surface of the ground electrode facing the discharge electrode, and harmful substances in the liquid can be efficiently removed.

  Further according to the invention, the predetermined gas is an inert gas and the liquid to be treated is an insulating oil containing polychlorinated biphenyl. Since the predetermined gas is an inert gas, the properties of the insulating oil are not adversely affected. Also, since the insulating oil contains fine bubbles formed by inert gas, the electrical insulation performance of the insulating oil is reduced, that is, the conductivity is improved, and polychlorinated biphenyl is decomposed and removed by non-equilibrium plasma. Can do.

  Further according to the invention, the predetermined gas is pure oxygen and the liquid to be treated is an insulating oil containing polychlorinated biphenyl. The fine bubbles formed by oxygen generate radicals (O radicals and the like) when they disappear, and thereby polychlorinated biphenyl contained in the insulating oil can be decomposed and removed.

  Furthermore, according to the present invention, the predetermined gas is ozone, and the liquid to be treated is a liquid infectious waste containing a water-soluble harmful substance. As a result, liquid infectious waste can be sterilized by ozone, and when fine bubbles disappear, ozone is decomposed to generate radicals, which can decompose and remove water-soluble harmful substances. .

1 is an overall view schematically showing a hazardous substance-containing liquid processing apparatus according to a first embodiment of the present invention. It is sectional drawing which shows the cross section which cut | disconnected the bubble generator by the virtual plane perpendicular | vertical to the axis line. It is sectional drawing which cut | disconnected the bubble generation apparatus by the cutting line AA of FIG. It is sectional drawing which expands and shows a part of 2nd process part. It is a general view which shows schematically the hazardous substance containing liquid processing apparatus of the 2nd Embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The embodiments described below are illustrated for embodying the technology according to the present invention, and do not limit the technical scope of the present invention. The technical contents according to the present invention can be variously modified within the technical scope described in the claims.

(First embodiment)
FIG. 1 is an overall view schematically showing a hazardous substance-containing liquid processing apparatus 1 according to a first embodiment of the present invention. The toxic substance-containing liquid processing apparatus 1 (hereinafter sometimes simply referred to as “processing apparatus 1”) includes a processing liquid storage tank 2, which is a liquid storage section, a first processing section 3, a second processing section 4, And a treated liquid collection tank 5 which is a liquid collection unit. In addition, such a processing apparatus 1 is used in a state where a liquid to be processed containing a harmful substance does not adversely affect the external environment.

  The processing liquid storage tank 2 is made of stainless steel and stores a liquid to be processed (hereinafter, simply referred to as “processing liquid”) containing a toxic substance. In this embodiment, the liquid to be treated containing a harmful substance is an insulating oil containing polychlorinated biphenyl (abbreviated as PCB).

  The first processing unit 3 supplies a predetermined gas to the liquid supplied from the processing liquid storage tank 2 under pressure to contain fine bubbles having a diameter of 50 μm or less. In the present embodiment, the predetermined gas is argon. The second processing unit 4 generates non-equilibrium plasma by discharge and processes the liquid containing fine bubbles supplied from the first processing unit 3. The processed liquid recovery tank 5 recovers the liquid processed by the second processing unit 4. The processing liquid storage tank 2, the first processing unit 3, the second processing unit 4, and the processed liquid recovery tank 5 are connected through flow paths 6, 7, 8, 9, and 10.

  The first processing unit 3 includes a bubble generation device 22, a pressure reactor 23, a pump device 24, and a gas supply device 25.

  FIG. 2 is a cross-sectional view showing a cross section of the bubble generating device 22 cut along a virtual plane perpendicular to the axis L2. 3 is a cross-sectional view of the bubble generating device 22 taken along the cutting line AA of FIG.

  The bubble generating device 22 is generally formed in a cylindrical shape, and is made of a material having excellent corrosion resistance, such as stainless steel, titanium or carbonite, and a synthetic resin such as ABS. Hereinafter, a direction parallel to the axis L2 of the bubble generating device 22 is referred to as an axial direction. The bubble generating device 22 includes a housing 26, and the housing 26 includes a first housing 27, a second housing 28, a first lid 29, and a second lid 30. It is.

  The first housing 27 is a member that is generally formed in a cylindrical shape. The axis of the first housing 27 coincides with the axis L2 of the bubble generating device 22. The inner peripheral surface portion 31 of the first housing 27 is partially tapered. Specifically, the inner peripheral surface portion 31 of the first housing 27 includes a first lid mounting portion 31a that is one end portion thereof and a treatment liquid introduction portion 31b that is the other end portion around the axis L2, respectively. Cross sections obtained by cutting along a virtual plane perpendicular to the axis L2, that is, cross sections perpendicular to the axis, are formed into circular shapes having the same diameter.

  The first lid mounting portion 31a is formed with a larger diameter than the processing liquid introduction portion 31b. The turning portion 31c, which is an intermediate portion of the inner peripheral surface portion 31, is formed around the axis L2, and one end in the axial direction is connected to the first lid mounting portion 31a, and the other end in the axial direction is connected to the processing liquid introduction portion 31b. The turning portion 31c has a circular cross section perpendicular to the axis, and is formed in a tapered shape that tapers from one end to the other in the axial direction. In the present embodiment, the turning portion 31c is linearly inclined inward in the radial direction from one end in the axial direction toward the other end. However, it is not limited to being inclined linearly, and may be curved inward in the radial direction from one end in the axial direction toward the other end.

  As for the 1st housing | casing 27, the outer peripheral surface part 32 becomes small in steps toward the other end part from the axial direction one end part. The portion of the first housing 27 that is formed to have the largest diameter is referred to as a large diameter portion 33, and the portion that is formed to have the smallest diameter is referred to as a small diameter portion 34, which is smaller in diameter than the large diameter portion 33 and has a small diameter portion 34. The portion formed with a larger diameter is referred to as a medium diameter portion 35. In the first housing 27, a large diameter portion 33, a medium diameter portion 35, and a small diameter portion 34 are formed in this order from one axial end portion to the other end portion. In the present embodiment, the inner peripheral surface portion 31 of the large diameter portion 33 corresponds to the first lid mounting portion 31a and the turning portion 31c, and the inner peripheral surface portions of the medium diameter portion 35 and the small diameter portion 34 correspond to the processing liquid introduction portion 31b. To do.

  The second housing 28 includes a circulation path forming part 36 and a processing liquid supply pipe part 37. This will be described with reference to FIGS. The circulation path forming portion 36 is formed in a cylindrical shape whose axis coincides with the axis L 2, and the outer diameter thereof coincides with the outer diameter of the large diameter portion 33 of the first housing 27. The inner peripheral portion of the circulation path forming portion 36 is formed in a circular shape having the same diameter as the outer diameter of the medium diameter portion 35 of the first housing 27 in a cross section perpendicular to the axis, and the medium diameter portion 35 of the first housing 27 is fitted therein. It is formed as follows. The circulation path forming part 36 forms a circulation flow path 38 between the small diameter part 34 of the first housing 27 in a state in which the medium diameter part 35 is fitted at one end in the axial direction.

  The processing liquid supply pipe section 37 is formed in a cylindrical shape, and is disposed on the outer peripheral portion of the circulation path forming section 36 so that the axis L3 is included on a virtual plane perpendicular to the axis L2. In FIG. 2, for convenience of explanation, the processing liquid supply pipe part 37 is shifted in the circumferential direction with respect to the circulation path forming part 36. Specifically, when the inner diameter of the processing liquid supply pipe section 37 is r and the inner diameter of the circulation path forming section 36 is R, a virtual one plane including the axis L3 and parallel to the axis L2 and the axis L2 It is arranged on the outer periphery of the circulation path forming portion 36 so that the angle formed by the tangential plane at the intersection line of the virtual plane P1 having the center radius Rr with the virtual plane is an angle α. In the present embodiment, the angle α is 0 degree. However, α is not limited to 0 degree, and may be within a range of 0 ≦ α <90. The second casing 28 is formed with a processing liquid supply flow path portion 39 that is formed along the axis L3 of the processing liquid supply pipe section 37 and opens inward of the circulation path forming section 36.

  The first lid 29 is generally formed in a cylindrical shape, and its axis coincides with the axis L2. The first lid 29 includes a cylindrical portion 40 that extends along the axis L <b> 2 and a conical portion 40 a that is continuous with one end of the cylindrical portion 40 in the axial direction. The cylindrical portion 40 functions as a gas reservoir 47 in its internal space. The conical portion 40a protrudes from the one end portion in the axial direction of the cylindrical portion 40 toward the second housing 28 and has a vertex on the axis L2. Further, the conical portion 40a is formed with a gas supply passage portion 41 that extends along the axis L2 and opens at both ends in the axial direction of the conical portion 40a. A check that prevents the processing liquid supplied into the first housing 27 from flowing into the gas reservoir 47 through the gas supply channel 41 is provided at the opening of the gas supply channel 41 on the cylindrical portion 40 side. A valve 48 is provided.

  The second lid 30 is generally formed in a disc shape, and its axis coincides with the axis L2. The second lid 30 is formed with a discharge flow path portion 42 that opens at one end and the other end in the axial direction along the axis L2. The discharge channel portion 42 opens at one end portion in the axial direction of the second lid body 30, and tapers the first channel portion 42 a that tapers toward the other end portion in the axial direction, and the axis line of the second lid body 30. And a tapered second flow path portion 42b that opens at the other end in the direction and tapers toward the one end of the axis. The first and second flow path portions 42a and 42b are connected to each other, and the connected portion is the narrowest portion of the discharge flow path portion 42, and this portion is referred to as a throat portion 42c.

  The middle diameter portion 35 of the first housing 27 is fitted into the inner peripheral portion of the second housing 28 in a state where sealing is achieved by the one end portion in the axial direction of the second housing 28 and the large diameter portion 33. Yes. The conical portion 40 a of the first lid body 29 is formed so that its outer peripheral portion comes into contact with and fits into the inner peripheral portion of the large-diameter portion 33. The first lid body 29 has its cylindrical portion 40 brought into contact with one end portion in the axial direction of the first casing 27, that is, one end portion in the axial direction of the large diameter portion 33 to achieve sealing, and the conical portion 40a. Is fitted into the first lid mounting portion 31a. Further, the second lid 30 is formed so that the outer peripheral portion thereof is in contact with and fitted into the inner peripheral portion of the second housing 28.

  The second lid 30 is fitted to the other axial end of the second casing 28 in a state where a seal is achieved, and one axial end thereof is the other axial end of the first casing 27, that is, a small diameter. The part 34 is in contact. With this configuration, a swirl space 43 surrounded by the first casing 27, the first lid 29, and the second lid 30 is formed inside the bubble generating device 22. The small-diameter portion 34, the medium-diameter portion 35, the circulation path forming portion 36, and the second lid body 30 form a circulation channel portion 44 that forms an annular circulation channel 38. The circulation channel 38 is formed so that the processing liquid can be circulated.

  The small-diameter portion 34 of the first housing 27 communicates with the circulation flow path 38 and the swirl space 43, and a plurality of treatment liquid introduction flow path portions 45 that introduce the treatment liquid circulating through the circulation flow path 38 into the swirl space 43. Is formed. Each processing liquid introduction flow path portion 45 that is an introduction flow path portion is formed at the other end in the axial direction of the first housing 27, and openings 46 that open to the swirl space are formed at equal intervals in the circumferential direction. Yes. A single treatment liquid introduction channel 45 may be formed, or a plurality of treatment liquid introduction channels 45 may be formed. In the present embodiment, three treatment liquid introduction flow path portions 45 are formed in the small diameter portion 34, and are formed 60 degrees apart from each other in the circumferential direction of the treatment liquid introduction portion 31b.

  The processing liquid introduction flow path section 45 is formed so that the processing liquid circulating in the circulation flow path 38 can be introduced into the swirl space 43 along the processing liquid introduction section 31b. Specifically, each processing liquid introduction channel section 45 has a downstream wall surface 45a extending in a direction parallel to the tangent line from the processing liquid introduction section 31b on the cross section perpendicular to the axis, and an upstream wall surface 45b. Is formed in parallel to the downstream wall 45a.

  Further, each processing liquid introduction flow path portion 45 is opened in one axial direction, and its bottom portion 45 c is formed on one axial direction side from the processing liquid supply flow path portion 39. One axial direction is a direction from one end of the first housing 27 in the axial direction toward the other end. The opening 46 of the processing liquid supply flow path section 39 is disposed so as to face the wall surface between two processing liquid introduction flow path sections 45 adjacent to each other in the circumferential direction, and is supplied from the processing liquid supply flow path section 39. Thus, the treated liquid is prevented from being directly introduced into the treated liquid introduction flow path section 45. However, the processing liquid introduction channel 45 may be configured to face the opening 46.

With reference to FIG. 1, the pump device 24 is configured to be able to suck the processing liquid from the suction port and configured to be able to discharge the processing liquid from the discharge port. The suction port of the pump device 24 is connected to the processing liquid storage tank 2, and the discharge port of the pump device 24 is connected to the processing liquid supply flow path portion 39 by the processing liquid supply pipe 50, and the processing liquid sucked from the suction port Is configured to be pressure-feedable to the processing liquid supply flow path portion 39. As the pump device 24, for example, a gear pump HSR-8-60 type manufactured by Daito Kogyo is used. The pressure applied to the bubble generator 22 from the pump device 24 is, for example, 5 to 6 kg / cm ² (490 to 588 kPa).

  An opening / closing valve 49 is interposed in the processing liquid supply pipe 50 so that the pipe line of the processing liquid supply pipe 50 can be opened and closed.

  The gas supply device 25 includes a gas cylinder 25a in which an inert gas (argon in the present embodiment) is sealed in a pressurized state, and a gas supply pipe 55. One end of a gas supply pipe 55 is connected to the gas outlet of the gas cylinder 25a. The other end of the gas supply pipe 55 is connected to the other end in the axial direction of the cylindrical portion 40 of the first lid 29. As described above, the gas cylinder 25a is connected to the gas supply channel 41 via the gas supply pipe 55, the gas reservoir 47, and the check valve 48, and the gas (argon) in the gas cylinder 25a is connected to the gas supply channel 41. It is configured to be pumpable.

As for the 1st process part 3 comprised in this way, the bubble generator 22 is provided in the pressure reactor 23. FIG. The pressure reactor 23 is a so-called autoclave, and has a reaction chamber 56 that can be filled with a processing liquid and can be maintained at a pressure higher than atmospheric pressure. The pressure is, for example, ^{2 to 4} kg / cm ² (196 to 392 kPa). The bubble generator 22 is provided in the reaction chamber 56.

  With such a configuration, the processing liquid introduced from each processing liquid introduction flow path section 45 swirls around the turning space 43 around the axis L2 along the processing liquid introduction section 31b, and the axial direction of the first casing 27 An outer swirling flow toward the other end is generated. The outer swirling flow is swung along the swirling portion 31 c and spreads outward in the radial direction at the swirling portion 31 c, and reaches one end in the axial direction of the first housing 27. The outer swirl flow that reaches one end in the axial direction of the first housing 27 turns into an inner swirl flow that goes in one axial direction.

  The inner swirl flow swirls around the axis L2, and from the other end in the axial direction of the first housing 27 toward the apex along the conical portion 40a of the first lid 29, and then in the radial direction of the outer swirl flow The direction is directed to the discharge channel portion 42. The pressure at the center of the inner swirling flow is lower than the pressure in the gas supply pipe 55. At this time, when the on-off valve of the gas cylinder 25a is opened, gas, argon in this embodiment, is sucked from the gas supply flow path portion 41. The sucked gas swirls around the axis L <b> 2 at the center of the inner swirling flow, and generates a swirling gas flow from the gas supply channel 41 to the discharge channel 42. In this way, a gas-liquid two-phase flow between the gas and the processing liquid can be generated.

  The inner swirling flow and the gas swirling flow that have reached the discharge flow path portion 42 are discharged into the reaction chamber 56 via the discharge flow path portion 42. At this time, when the flow rate and speed of the processing liquid introduced from each processing liquid introduction flow path section 45 reach a predetermined flow volume and speed, the speed of the gas swirl flow is changed to the first flow path of the discharge flow path section 42. In part 42a, subsonic speed is reached. Since the inside and the gas swirl flow are directed toward the discharge flow path portion 42, the pressure of the gas passing through the discharge flow path portion 42 is higher outside the bubble generating device 22, that is, the reaction chamber 56. As a result, the speed of the gas swirling flow in the throat portion 42c of the discharge flow path portion 42 becomes the speed of sound, and exceeds the speed of sound in the second flow path portion 42b.

  When the gas swirl flow exceeds the speed of sound at the throat portion 42c, the gas swirl flow collides with the barrier and is dispersed, that is, the gas is dispersed in the treatment liquid flowing along with the gas through the discharge flow path portion 42. By this dispersion, the gas becomes fine bubbles such as microbubbles having a diameter of 50 μm or less, is discharged from the discharge flow path portion 42 together with the processing liquid, and discharges the fine bubbles into the reaction chamber 56. An ultrasonic generator may be provided in the vicinity of the discharge channel portion 42. By applying ultrasonic waves from the ultrasonic generator to the fine bubbles released from the discharge flow path portion 42, the fine bubbles can be made into fine bubbles having a nano-order diameter, for example.

  The gas supplied from the gas supply device 25 is supplied to the gas reservoir 47 in the first lid 29, and then supplied to the gas supply channel portion 41 via the check valve 48. Therefore, even if the gas supply amount from the gas supply device 25 fluctuates, the gas reservoir 47 functions as a buffer, and the gas can be stably supplied to the gas supply flow path portion 41. In addition, since the first lid 29 is provided with the check valve 48, the processing liquid in the swirling space 43 is supplied to the gas supply device 25 side even when no gas is supplied from the gas supply device 25. Backflow can be prevented.

  In this way, fine bubbles can be generated in the reaction chamber 56. Moreover, since the processing liquid discharged into the reaction chamber 56 is pumped by a pump, the pressure in the reaction chamber 56 can be increased. Also, the pressure in the reaction chamber 56 can be increased by generating fine bubbles. In the reaction chamber 56, the fine bubbles are dissolved in the processing liquid by a cavitation phenomenon. When the dissolved fine bubbles are discharged from the reaction chamber 56, they appear again in the processing liquid, and the foreign substances in the processing liquid are floated and separated. In the present embodiment, the fine bubbles contained in the insulating oil disappear in about 10 minutes under atmospheric pressure.

  Referring to FIG. 1, the second processing unit 4 is provided on the downstream side in the flow direction of the processing liquid of the first processing unit 3. The second processing unit 4 generates non-equilibrium plasma by discharge to process the liquid containing fine bubbles supplied from the first processing unit 3. The second processing unit 4 includes a non-equilibrium plasma generating unit 60 that generates non-equilibrium plasma, a first liquid supply unit 61, and a second liquid supply unit 62.

  Here, non-equilibrium plasma is plasma in which the electron temperature of ionized electrons is higher than the ion temperature of ionized ions, and the electron temperature and ion temperature are not thermodynamically balanced. In such a non-equilibrium plasma, high-speed electrons can be obtained with the temperature of the non-equilibrium plasma maintained at room temperature. The high-speed electrons obtained in this way collide with molecules in the gas to generate chemically active species rich in reactivity such as radicals, excited molecules, ions or ozone.

  The non-equilibrium plasma generation unit 60 includes a linear discharge electrode 63, a cylindrical ground electrode 64, a pulse power supply device 65 that is a power supply device, and a housing 66. The discharge electrode 63 and the ground electrode 64 are accommodated in the housing 66. Discharge electrode 63 extends vertically and is made of a conductive material, for example, a steel linear body, and both ends thereof are connected to housing 66 via insulators 67a and 67b. The ground electrode 64 is formed in a cylindrical shape, is made of a conductive material, such as stainless steel, is provided coaxially with the discharge electrode 63, and surrounds the discharge electrode 63 and extends vertically. That is, the ground electrode 64 extends vertically so as to face the discharge electrode 63. Further, the surface of the ground electrode 64 facing the discharge electrode 63, that is, the inner peripheral surface of the ground electrode 64 is subjected to a roughening process. Examples of the roughening treatment include treatment with abrasive cloth such as sandpaper or sandblasting. The positive electrode of the pulse power supply device 65 is connected to the upper end of the discharge electrode 63.

  An air intake 68 is provided at the upper portion of the housing 66 so as to face the insulator 67 a, and an air discharge port 69 is provided at the lower portion of the housing 66. The air discharge port 69 is connected to the exhaust fan 71 via the gas discharge path 70. When the exhaust fan 71 operates, the air is taken in from the air intake 68, and the taken-in air is exhausted to the outside through the space surrounded by the ground electrode 64, the air exhaust port 69, the gas exhaust path 70, and the exhaust fan 71. Is done. As a result, while the exhaust fan 71 is operating, fresh air is brought into the insulator 67a, so that the insulator 67a is prevented from being soiled and the electrical insulation performance of the insulator 67a can be prevented from being lowered. Note that the gas exhaust path 70 may be provided with a post-treatment device such as a catalyst device filled with a catalyst such as manganese dioxide, an activated carbon adsorption device, or a non-equilibrium plasma generator.

  In order to generate non-equilibrium plasma, corona discharge is generated between the discharge electrode 63 and the ground electrode 64, and the gas between the discharge electrode 63 and the ground electrode 64 is ionized. Here, as an example of the dimensions of the discharge electrode 63 and the ground electrode 64, the thickness of the discharge electrode 63 is selected to be about 2 to 6 mm, preferably about 4 mm. The inner diameter of the ground electrode 64 is selected to be about 50 to 1000 mm, preferably about 180 mm. At this time, a pulse having a DC voltage of 30 k to 200 kV, preferably 100 k to 200 kV, a frequency of 100 to 2000 Hz, that is, a period T = 500 μs to 10 ms, preferably a frequency of 1000 Hz, that is, a period T = 1 ms, is provided between the discharge electrode 63 and the ground electrode 64. A voltage is applied. The voltage rise time τ is, for example, 20 to 300 ns, preferably 100 ns, and only electrons with a small mass are accelerated during this extremely short rise time τ to obtain high-speed electrons. In addition, since the cycle of the pulse voltage is sufficiently longer than the rise time τ, cooling is performed during this period, and when the next pulse voltage is applied, the initial state is restored again, and the temperature rise of the gas is suppressed. Is kept at room temperature.

  Here, the polarity of the pulse voltage is such that the discharge electrode 63 is a positive electrode and the ground electrode 64 is a negative electrode. This is because the positive streamer corona has a strong tendency to progress, bridges the space between the discharge electrode 63 and the ground electrode 64, generates non-equilibrium plasma over the entire space, and the reaction effect per unit volume is greatly improved. Because. The applied voltage is determined with respect to the discharge distance between the discharge electrode 63 and the ground electrode 64. That is, a high voltage is applied when the discharge distance is large, and a low voltage is applied when the discharge distance is small.

  FIG. 4 is an enlarged cross-sectional view showing a part of the second processing unit 4. The first liquid supply unit 61 is provided above the ground electrode 64 and supplies the liquid supplied from the first processing unit 3 via the flow path 8 to the inner peripheral surface of the ground electrode 64. The first liquid supply part 61 includes an annular bottom wall part 72 and a cylindrical side wall part 73 erected on the outer edge of the bottom wall part 72. The bottom wall portion 72 is provided at a position below the upper end 64a of the ground electrode 64 by a predetermined distance. The inner diameter of the bottom wall portion 72 substantially matches the outer diameter of the ground electrode 64. The outer diameter of the bottom wall portion 72 is sized so as to reach the inner peripheral surface of the housing 66. The side wall 73 is provided such that its outer peripheral surface is in contact with the inner peripheral surface of the housing 66. The upper end 73 a of the side wall portion 73 is disposed above the upper end 64 a of the ground electrode 64. In the first liquid supply part 61, the tip 8 a of the flow path 8 is provided through the housing 66 and the side wall part 73. The bottom wall portion 72 and the ground electrode 64 are provided in a watertight manner, and the tip 8a of the flow path 8, the housing 66, and the side wall portion 73 are provided in a watertight manner.

  The liquid containing fine bubbles supplied from the first processing unit 3 to the first liquid supply unit 61 through the flow path 8 is in a space formed by the bottom wall 72, the ground electrode 64, and the side wall 73. Stored. When the liquid level of the stored liquid rises to the upper end 64a of the ground electrode 64 and the liquid is further supplied from the first processing unit 3, the liquid passes over the upper end 64a of the ground electrode 64 and enters the inside of the ground electrode 64. It flows down along the circumference. Since the inner peripheral surface of the ground electrode 64 is roughened, the liquid to be processed can flow uniformly over the entire inner peripheral surface of the ground electrode 64. The supply amount of the liquid supplied to the first liquid supply unit 61 is adjusted by adjusting the opening / closing of various opening / closing valves provided in the flow path 8. Excess liquid that is not supplied from the first processing unit 3 to the first liquid supply unit 61 by the adjustment may be returned to the processing liquid storage tank 2 via the flow path 9 branched from the flow path 8.

  Referring to FIG. 1, the second liquid supply unit 62 is provided below the ground electrode 64 and flows down on the inner peripheral surface of the ground electrode 64 to receive the liquid processed by the non-equilibrium plasma. The treated liquid is supplied to the liquid recovery tank 5. The second liquid supply unit 62 includes a liquid receiving unit 74 that receives the processed liquid, and a liquid supply pipe 75 that supplies the liquid received by the liquid receiving unit 74 to the processed liquid recovery tank 5.

  The liquid that has flowed down on the inner peripheral surface of the ground electrode 64 and has been treated by the non-equilibrium plasma is received by the liquid receiving portion 74. The processed liquid received by the liquid receiving unit 74 is supplied to the processed liquid recovery tank 5 through the liquid supply pipe 75 and recovered. The liquid stored in the treated liquid recovery tank 5 may be supplied to the flow path 7 via the flow path 10 and circulated in the processing apparatus 1.

  According to the present invention, the liquid to be processed containing the harmful substance stored in the processing liquid storage tank 2 is supplied to the first processing unit 3. In the 1st process part 3, the predetermined gas is supplied to the liquid supplied from the process liquid storage tank 2 under pressure, and a fine bubble is contained. Thereby, the conductivity of the liquid containing fine bubbles is improved as compared with that before the treatment.

  The liquid containing fine bubbles in the first processing unit 3 is supplied to the second processing unit 4. In the second processing unit 4, the internal air is ionized into electrons and ions by discharge, and the electron temperature and the ion temperature are thermodynamically balanced while the electron temperature of the electrons is higher than the ion temperature of the ions. A non-equilibrium plasma that is not in a state is generated. In the second processing unit 4, high-speed electrons can be obtained in a state where the temperature of the non-equilibrium plasma is kept at room temperature. This high-speed electron collides with various molecules in the air, and generates chemically active species rich in reactivity, such as radicals, excited molecules, and ions. The harmful components contained in the liquid are decomposed and removed by a chemical reaction by chemically active species together with high-speed electron collision. The fine bubbles contained in the liquid are negatively charged, and when the fine bubbles disappear, the temperature inside the bubbles becomes high and the pressure becomes high. When the microbubbles are negatively charged, harmful components are attracted, and the high-temperature and high-pressure conditions that occur when the microbubbles are extinguished breaks down the gas that forms the bubbles, generating powerful radicals. Harmful components are removed by radicals. Even if the harmful substance in the liquid is released from the liquid in the non-equilibrium plasma generation unit 60 of the second processing unit 4, the harmful substance is exposed to the non-equilibrium plasma atmosphere. It is decomposed and removed by the equilibrium plasma and can be processed safely. In this way, the liquid containing fine bubbles supplied from the first processing unit 3 is processed.

  The liquid from which harmful substances have been decomposed and removed by the second processing unit 4 is collected in the treated liquid collection tank 5.

  As described above, since the fine bubbles are contained in the liquid containing the harmful substance in the first processing unit 3, the conductivity of the liquid is improved, and the liquid containing the fine bubbles is supplied to the second processing unit 4. However, the second processing unit 4 can stably discharge, and can generate non-equilibrium plasma stably. Due to the synergistic effect of the decomposition and removal of harmful substances by non-equilibrium plasma and the decomposition and removal of harmful substances caused by the disappearance of fine bubbles, the harmful substances in the liquid in the equipment having at least the first processing unit 3 and the second processing unit 4 Can be efficiently removed.

  According to the invention, the second processing unit 4 includes the linear discharge electrode 63 extending vertically, the ground electrode 64, the pulse power supply device 65, the first liquid supply unit 61, and the second liquid supply unit 62. Including. The ground electrode 64 extends vertically to face the discharge electrode 63. The pulse power supply device 65 supplies power for generating non-equilibrium plasma to the discharge electrode 63. The first liquid supply unit 61 is provided above the ground electrode 64 and supplies the liquid supplied from the first processing unit 3 to the surface of the ground electrode 64 facing the discharge electrode 63. The second liquid supply unit 62 is provided below the ground electrode 64, flows down on the surface of the ground electrode 64 facing the discharge electrode 63, receives the liquid treated in the non-equilibrium plasma atmosphere, and collects the treated liquid. The treated liquid is supplied to the tank 5.

  The liquid containing fine bubbles is supplied by the first liquid supply unit 61 onto the surface of the ground electrode 64 that faces the discharge electrode 63, and flows down on the surface of the ground electrode 64 that faces the discharge electrode 63, thereby supplying the second liquid. It is received by the part 62. The surface of the ground electrode 64 facing the discharge electrode 63 is wet with a liquid containing fine bubbles. Since fine bubbles are contained in the liquid, the conductivity of the liquid is improved, and even when the liquid exists on the surface of the ground electrode 64 facing the discharge electrode 63, the discharge can be performed stably. it can. Therefore, the liquid containing the harmful substance containing fine bubbles can pass through the non-equilibrium plasma atmosphere formed between the discharge electrode 63 and the earth electrode 64, and the harmful substance in the liquid can be removed.

  Furthermore, according to the present invention, the surface of the ground electrode 64 facing the discharge electrode 63 is subjected to a roughening process. As a result, the liquid to be treated can be made to flow uniformly over the entire surface of the ground electrode 64 facing the discharge electrode 63, and harmful substances in the liquid can be efficiently removed.

  Further according to the invention, the predetermined gas is an inert gas and the liquid to be treated is an insulating oil containing polychlorinated biphenyl. Since the predetermined gas is an inert gas, the properties of the insulating oil are not adversely affected. Also, since the insulating oil contains fine bubbles formed by inert gas, the electrical insulation performance of the insulating oil is reduced, that is, the conductivity is improved, and polychlorinated biphenyl is decomposed and removed by non-equilibrium plasma. Can do.

  In the present embodiment, the case where the inert gas is argon has been described. However, the present invention is not limited to this, and other inert gas such as helium or neon may be used.

  In the present embodiment, the case where the predetermined gas is an inert gas has been described. However, the present invention is not limited to this, and an active gas such as pure oxygen may be used. The fine bubbles formed by oxygen generate radicals (O radicals and the like) when they disappear, and thereby polychlorinated biphenyl contained in the insulating oil can be decomposed and removed. Alternatively, the predetermined gas may be carbon dioxide. By using carbon dioxide for forming fine bubbles, radicals are easily generated.

(Second Embodiment)
FIG. 5 is an overall view schematically showing a hazardous substance-containing liquid processing apparatus 1A according to the second embodiment of the present invention. In the present embodiment, portions corresponding to the configuration of the above-described embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

  The toxic substance-containing liquid processing apparatus 1A (hereinafter sometimes simply referred to as “processing apparatus 1A”) is similar to the configuration of the processing apparatus 1 of the above-described embodiment, and it should be noted that the configuration of the first processing unit 3A is notable. Unlike the 1st process part 3 of the processing apparatus 1, the liquid which should contain the hazardous | toxic substance differs. The processing apparatus 1A includes a processing liquid storage tank 2 that is a liquid storage unit, a first processing unit 3A, a second processing unit 4, and a processed liquid recovery tank 5 that is a liquid recovery unit. In the present embodiment, the liquid to be treated that contains harmful substances stored in the treatment liquid storage tank 2 contains water-soluble harmful substances such as human waste, body fluids, and blood that are generated by artificial dialysis, surgery, or examination. Liquid infectious waste.

  The first processing unit 3A supplies a predetermined gas to the liquid supplied from the processing liquid storage tank 2 under pressure to contain fine bubbles having a diameter of 50 μm or less. In the present embodiment, the predetermined gas is ozone. The second processing unit 4 generates non-equilibrium plasma by discharge and processes the liquid containing fine bubbles supplied from the first processing unit 3A. The processing liquid storage tank 2, the first processing unit 3 </ b> A, the second processing unit 4, and the processed liquid recovery tank 5 are connected via flow paths 6, 7, 8, 9, and 10.

The first processing unit 3A includes a bubble generation device 22, a pressure reactor 23, a pump device 24A, and a gas supply device 25A. The pump device 24A is configured to be able to suck the processing liquid from the suction port and configured to be able to discharge the processing liquid from the discharge port. The suction port of the pump device 24A is connected to the processing liquid storage tank 2, and the discharge port of the pump device 24A is connected to the processing liquid supply flow path portion 39 by the processing liquid supply pipe 50, and the processing liquid sucked from the suction port. Is configured to be pressure-feedable to the processing liquid supply flow path portion 39. For example, an EBARA barreled motor pump MMLF / AAVF type is used for the pump device 24A. The pressure applied to the bubble generating device 22 from the pump device 24A is, for example, 5 to 6 kg / cm ² (490 to 588 kPa).

  The gas supply device 25 </ b> A includes a compressor 51, an oxygen concentrator 52, an ozone generator 53, a chiller 54, and a gas supply pipe 55. The compressor 51 is configured to be able to suck gas (air) from the suction port and configured to be able to discharge compressed gas from the discharge port.

  The discharge port of the compressor 51 is connected to the introduction port of the oxygen concentrator 52. The oxygen concentrator 52 concentrates the oxygen concentration of the compressed air supplied from the compressor 51 to 90% or more. The oxygen concentrator 52 has an exhaust port connected to the introduction port of the ozone generator 53. The ozone generator 53 generates ozone from the air in which oxygen is concentrated by the oxygen concentrator 52 by a creeping discharge method. The chiller 54 cools the ozone discharge part of the ozone generator 53. A gas supply pipe 55 is connected to the discharge port of the ozone generator 53. As described above, the compressor 51 is connected to the gas supply channel 41 via the oxygen concentrator 52, the ozone generator 53, and the gas supply pipe 55, and pumps the gas sucked from the suction port to the gas supply channel 41. It is configured to be possible.

  By comprising in this way, in the 1st process part 3A, the liquid which should be processed containing the micro bubble formed with ozone can be produced | generated.

  The liquid to be processed containing the generated fine bubbles is supplied from the first processing unit 3A to the second processing unit 4 through the flow path 8 in the same manner as the processing apparatus 1 of the above-described embodiment, and the non-equilibrium plasma is supplied. After the process is performed, the liquid is recovered in the processed liquid recovery tank 5.

  According to the invention, the predetermined gas is ozone and the liquid to be treated is a liquid infectious waste containing water-soluble harmful substances. As a result, liquid infectious waste can be sterilized by ozone, and when fine bubbles disappear, ozone is decomposed to generate radicals, which can decompose and remove water-soluble harmful substances. .

  Further, since the liquid to be processed contains fine bubbles having a diameter of 50 μm or less by the first processing unit 3A, the conductivity of the liquid is improved, and the liquid containing the fine bubbles is supplied to the second processing unit 4. Even in this case, it is possible to stably discharge in the second processing unit 4 and to stably generate non-equilibrium plasma. Due to the synergistic effect of the decomposition and removal of harmful substances by non-equilibrium plasma and the decomposition and removal of harmful substances generated when the fine bubbles disappear, at least in the equipment having the first processing section 3A and the second processing section 4, harmful substances in the liquid Can be efficiently removed.

  In the above-described embodiment, the ground electrode 64 is a cylindrical electrode, but is not limited thereto, and may be an electrode having another shape such as a flat plate shape or a corrugated plate shape.

  In the second embodiment of the present invention, the bubble generating device 22 is supplied with ozone generated by the gas supply device 25A. However, the present invention is not limited to this. Gas may be supplied.

DESCRIPTION OF SYMBOLS 1,1A Toxic substance containing liquid processing apparatus 2 Processing liquid storage tank 3,3A 1st processing part 4 2nd processing part 5 Processed liquid collection | recovery tank 22 Bubble generator 23 Pressure reactor 24, 24A Pump apparatus 25, 25A Gas supply Device 60 Non-equilibrium plasma generation unit 61 First liquid supply unit 62 Second liquid supply unit 63 Discharge electrode 64 Ground electrode 65 Pulse power supply device 66 Housing 67a, 67b Insulator 68 Air intake port 69 Air exhaust port 70 Gas exhaust channel 71 Exhaust gas fan

Claims (6)

A liquid reservoir for storing a liquid to be treated containing harmful substances;
A first processing unit for supplying a predetermined gas under pressure to the liquid supplied from the liquid storage unit and containing fine bubbles;
A second processing unit that generates non-equilibrium plasma by discharge and processes a liquid containing fine bubbles supplied from the first processing unit;
A toxic substance-containing liquid processing apparatus, comprising: a liquid recovery unit that recovers the liquid processed by the second processing unit. The second processing unit includes:
Linear discharge electrodes extending vertically;
A ground electrode extending vertically opposite the discharge electrode;
A power supply device for supplying power for generating non-equilibrium plasma to the discharge electrode;
A first liquid supply unit provided on the ground electrode and configured to supply the liquid supplied from the first processing unit to a surface of the ground electrode facing the discharge electrode;
A first liquid is provided below the ground electrode, flows down on the surface of the ground electrode facing the discharge electrode, receives liquid processed by non-equilibrium plasma, and supplies the processed liquid to the liquid recovery section. Two liquid supply units;
The toxic substance-containing liquid processing apparatus according to claim 1, comprising:   The hazardous substance-containing liquid processing apparatus according to claim 1, wherein a surface roughening treatment is performed on a surface of the ground electrode facing the discharge electrode.   4. The hazardous substance-containing material according to claim 1, wherein the predetermined gas is an inert gas, and the liquid to be treated is an insulating oil containing polychlorinated biphenyl. Liquid processing equipment.   The hazardous substance-containing liquid according to any one of claims 1 to 3, wherein the predetermined gas is pure oxygen, and the liquid to be treated is an insulating oil containing polychlorinated biphenyl. Processing equipment.   The harmful gas according to any one of claims 1 to 3, wherein the predetermined gas is ozone, and the liquid to be treated is a liquid infectious waste containing a water-soluble harmful substance. Substance-containing liquid processing equipment.

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