JP5085441B2 - Ozone generator and ozone generation method - Google Patents

Description

  The present invention relates to an ozone generator and an ozone generation method used for water treatment, deodorization, sterilization, decomposition of harmful substances, and the like.

  Patent Document 1 describes an example of a conventional ozone generator. This ozone generator is provided with an excitation coil for applying a magnetic field in the direction of the cylindrical axis on the outer peripheral portion of the outer electrode of the coaxial cylindrical ozone generator, and the excitation coil has a period of discharge current between the electrodes. It is comprised so that the synchronized alternating current may flow. With this device, collision between the discharge column and oxygen molecules is likely to occur, and ozone generation efficiency is improved.

JP-A-6-305709

  However, in the ozone generator described in Patent Document 1, if the interelectrode distance (discharge gap width) is not set appropriately, electrons are captured by the anode, and the movement distance of electrons in the discharge gap is short. As a result, the collision frequency between electrons and oxygen molecules is reduced.

  Then, an object of this invention is to provide the ozone generation apparatus and ozone generation method which improve the generation efficiency of ozone reliably.

  In order to solve the above-described problems, an ozone generator according to the present invention includes a cylindrical inner electrode, an outer electrode disposed radially outside the inner electrode, and the inner electrode and the outer electrode. A magnetic field generating member that generates a magnetic field along an axial direction in the formed discharge space, a gas containing oxygen is introduced into the discharge space, and ozone is generated by the discharge in the discharge space; The width of the discharge space is determined from (i) the maximum value of the magnetic flux density generated in the discharge space by the magnetic field generating member, and (ii) the maximum value of the electric field generated in the discharge space. It is over the maximum width of the swivel movement.

  According to this configuration, a discharge space is formed between both electrodes (the inner electrode and the outer electrode). Then, ozone is generated by introducing a gas containing oxygen into the discharge space. Further, the electrons between the two electrodes are affected by the magnetic field generated by the magnetic field generating member, and perform a swiveling motion (cyclotron motion) by Lorentz force. Then, the center of rotation of electrons drifts in the circumferential direction.

  The maximum width of the cyclotron motion (maximum distance from the inner electrode) is determined from (i) the magnetic flux density generated by the magnetic field generating member and (ii) the magnitude of the electric field generated in the discharge space. If the width of the discharge space is set to be equal to or greater than the maximum width of the turning motion, the electron turning motion and the drift motion are not hindered, and the electron moving distance becomes longer. As described above, the collision frequency between oxygen molecules and electrons increases, and the ozone generation efficiency is reliably improved.

  Note that the ozone generator may include a dielectric between both electrodes. When the ozone generator includes a dielectric, the discharge space is formed between one of both electrodes and the dielectric.

  The “columnar” inner electrode includes a cylindrical electrode. The “axial direction” is the axial direction of the internal electrode, and the “radial direction” is the radial direction of the internal electrode.

  The magnetic field generated in the ozone generator may be an alternating magnetic field or a static magnetic field. In the case of a static magnetic field, the magnetic flux density generated in the discharge space is constant, so the “maximum value of magnetic flux density” is equal to this constant value.

  The electric field generated in the ozone generator may be an alternating electric field or an electrostatic field. In the case of an electrostatic field, since the magnitude of the electric field generated in the discharge space is constant, the “maximum value of the electric field” is equal to this constant value.

  By setting the width of the discharge space according to this concept, it is not necessary to enlarge the apparatus more than necessary. For example, by setting the width of the discharge space to be approximately equal to the maximum width of the cyclotron motion (slightly larger than the maximum width), the electron moving distance becomes long and the size of the device is suppressed.

  The ozone generator according to the present invention may further include a rotation mechanism that rotates at least one of the inner electrode and the outer electrode in the circumferential direction. According to this, since charges are not locally accumulated on the surface of the electrode (cathode), the discharge from the electrode surface is not disturbed locally, and the discharge is likely to occur.

  The “circumferential direction” is the circumferential direction of the inner electrode. When the outer electrode includes a plurality of electrodes, the present invention includes that the entire outer electrode rotates around the inner electrode.

  Regarding the rotation of the inner electrode and the outer electrode, the rotation may be performed so that charges are not accumulated locally on the electrode surface. For example, only the inner electrode or only the outer electrode may be rotated, or both the inner electrode and the outer electrode may be rotated. Further, the inner electrode and the outer electrode may be rotated in directions opposite to each other, or these may be rotated in the same direction. Further, the inner electrode may be rotated in the same direction with respect to the electron drift direction and faster than the electron drift speed. Further, the cathode (inner electrode or outer electrode) may be rotated in the opposite direction relative to the electron drift direction.

  Moreover, the ozone generator which concerns on this invention WHEREIN: The cylindrical electrode arrange | positioned concentrically with respect to the said inner side electrode may be sufficient as the said outer side electrode. According to this, the structure of an ozone generator can be simplified.

  Moreover, the ozone generator which concerns on this invention WHEREIN: The said outer side electrode consists of a some cylindrical electrode, and the axial direction in each of the said some cylindrical electrode may be parallel to the axial direction of the said inner side electrode. According to this, since a local electric field is formed between the inner electrode and the outer electrode, discharge between both electrodes is likely to occur, and the generation efficiency of ozone is further improved. The “columnar” outer electrode includes a cylindrical electrode.

  Moreover, in the ozone generator according to the present invention, the magnetic field generating member may be a solenoid-like excitation coil disposed concentrically with the inner electrode and the outer electrode on the radially outer side of the outer electrode. . According to this, a stable and uniform magnetic field can be formed in the discharge space. The excitation coil includes a ferromagnetic coil and an electromagnet coil.

  In the ozone generator according to the present invention, the magnetic field generating member may include a superconducting magnet. According to this, power consumption at the time of apparatus operation can be reduced. In addition, since a strong magnetic field can be generated, the maximum width of the cyclotron motion can be reduced, and the apparatus can be miniaturized. In addition, a stable and uniform magnetic field can be easily formed in the discharge space. Note that at least a part of the magnetic field generating member may be a superconducting magnet, and all of the magnetic field generating members may be superconducting magnets.

  In order to solve the above-described problem, an ozone generation method according to the present invention includes a cylindrical inner electrode, an outer electrode disposed radially outside the inner electrode, and the inner electrode and the outer electrode. An ozone generation method using an ozone generator having a magnetic field generating member that generates a magnetic field along an axial direction in a discharge space formed therebetween, wherein a gas containing oxygen is introduced into the discharge space, An ozone generation step of generating ozone by discharge in the discharge space, wherein in the ozone generation step, the width of the discharge space is (i) a maximum value of magnetic flux density generated in the discharge space by the magnetic field generating member; (Ii) The maximum value of the electric field generated in the discharge space is greater than the maximum width of the swirling motion of electrons in the discharge space.

  When the width of the discharge space is set to be equal to or greater than the maximum width of the swirl motion by this method, the electron swivel motion and drift motion are not hindered, and the electron travel distance becomes long. Therefore, the collision frequency between oxygen molecules and electrons increases, and the ozone generation efficiency is reliably improved.

(About overall structure)
Next, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing the structure of an ozone generator according to the first embodiment of the present invention. 2 is a cross-sectional view taken along the line AA ′ in FIG. FIG. 3 is an enlarged cross-sectional view showing the main part of FIG. In the following description, “axial direction”, “radial direction”, and “circumferential direction” indicate an axial direction, a radial direction, and a circumferential direction with reference to the inner electrode (see arrow directions in the drawing).

  First, the whole structure of the ozone generator 1 which concerns on this embodiment is demonstrated. As shown in FIG. 1, the ozone generator 1 includes an inner electrode 2, an outer electrode 3, a dielectric 4, a solenoid-like excitation coil 5, and a motor 8. The ozone generator 1 is electrically connected to the AC power source 7a and the DC power source 7b.

  The dielectric 4, the outer electrode 3, and the solenoidal excitation coil 5 are disposed concentrically with the inner electrode 2, and a discharge space 6 is formed between the inner electrode 2 and the dielectric 4 (see FIG. 1 and FIG. 1). (See FIG. 2). When a gas containing oxygen is introduced into the discharge space 6 and a voltage (potential difference) is applied between both electrodes (the inner electrode 2 and the outer electrode 3), a silent discharge occurs between the two electrodes. As a result, oxygen in the gas is converted into ozone.

(electrode)
Next, both electrodes (inner electrode 2 and outer electrode 3) will be described. The inner electrode 2 is made of aluminum and is formed in a cylindrical shape. The outer electrode 3 is made of aluminum, is formed in a cylindrical shape, and is arranged concentrically with the inner electrode 2. Further, the outer electrode 3 is disposed on the outer side in the radial direction of the inner electrode 2, and a constant interval is provided between the outer peripheral surface of the inner electrode 2 and the inner peripheral surface of the outer electrode 3.

  An AC power source (electric field generating power source) 7 a is connected to the inner electrode 2 and the outer electrode 3. The power supply frequency of the AC power supply 7a is, for example, 50 Hz or 60 Hz. Each of the inner electrode 2 and the outer electrode 3 functions as an anode or a cathode, and the polarity (anode and cathode) in each electrode is periodically switched over time (the inner electrode 2 and the outer electrode). There is also a timing when 3 becomes the same potential). 1 to 3 show a state in which the inner electrode 2 is a cathode and the outer electrode 3 is an anode (the polarity may be reversed). In the case of FIGS. 1 to 3 (in the case where the inner electrode 2 is a cathode), an electric field E along the radial direction from the outer electrode 3 toward the inner electrode 2 is generated between both electrodes (for the direction of the electric field). FIG. 1 and FIG. 2 refer to the direction of arrow E).

  The material of the inner electrode may be aluminum, stainless steel, copper, or the like. The material of the outer electrode may be aluminum, stainless steel, copper, or the like. In addition, when the magnetic field generating member is an electromagnet, it is desirable to have a core made of a magnetic material (soft magnetic material) having a high magnetic permeability, so that either the inner electrode or the outer electrode is a soft magnetic material. Is desirable.

(Dielectric)
A dielectric 4 is disposed between both electrodes (see FIGS. 1 and 2). Specifically, a cylindrical dielectric 4 is disposed on the inner surface of the outer electrode 3. The dielectric 4 is an insulator, and in the ozone generator 1, glass is used as the dielectric 4. By disposing the dielectric 4 between both electrodes, uniform discharge can be realized. Specifically, since no current flows on the surface of the dielectric 4, the entire surface of the dielectric 4 can be discharged uniformly. As the dielectric material, ceramics other than glass, plastic materials, and the like can also be used. Further, there may be no dielectric.

(Discharge space)
A discharge space (discharge gap) 6 is formed between the inner electrode 2 and the outer electrode 3. Specifically, the discharge space 6 is formed between the inner electrode 2 and the dielectric 4. In the ozone generator 1, a gas containing oxygen molecules (O ₂ ) is introduced into the discharge space 6, and ozone (O ₃ ) is generated by the discharge in the discharge space 6. As shown in FIG. 1, in the ozone generator 1, the gas containing oxygen molecules is introduced from the lower side of FIG. 1, and the generated gas containing ozone is released upward in FIG. The discharge space 6 is an annular space, and air or the like is supplied to the discharge space 6 in order to generate ozone when the ozone generator 1 is used.

  When the ozone generator includes a dielectric as in the present embodiment, the discharge space is formed between one of the electrodes and the dielectric. That is, the dielectric may be disposed on the outer surface portion of the inner electrode. In this case, a discharge space is formed between the dielectric and the outer electrode.

(Magnetic field generating member)
A solenoid-like excitation coil 5 (magnetic field generating member) is disposed outside the outer electrode 3 in the radial direction. A direct current power source (magnetic field generating power source) 7 b is connected to the solenoid-like excitation coil 5. The solenoid-like excitation coil 5 is configured to generate a magnetic field along the axial direction in the discharge space 6. More specifically, when a direct current is passed through the solenoid-like excitation coil 5, a magnetic field is generated along the axial direction in the discharge space 6 as a result of generating a magnetic field around the solenoid-like excitation coil 5. In the present embodiment, a static magnetic field from the top to the bottom of FIG. 1 is generated in the discharge space 6 (see the direction of arrow B in FIGS. 1 and 2 for the direction of the magnetic field). The solenoid-like excitation coil 5 is disposed concentrically with respect to the inner electrode 2 and the outer electrode 3. In the present apparatus, the direction of the magnetic field (axial direction) and the direction of the electric field (radial direction) are perpendicular.

The solenoid-like excitation coil 5 is formed by a superconducting magnet. That is, the solenoid-like excitation coil 5 is a superconducting electromagnet. More specifically, the solenoid-like excitation coil 5 is formed by winding a wire made of a superconducting material into a solenoid shape (cylindrical shape). As the superconducting material, niobium titanium (NbTi), niobium tin (Nb ₃ Sn), or other high-temperature superconducting materials can be used.

  Since the solenoid excitation coil 5 is a superconducting magnet, a coolant (not shown) for the solenoid excitation coil 5 is required. The coolant for the solenoid-like excitation coil 5 may be any one that can maintain the superconducting state of the solenoid-like excitation coil 5, and may be a gas such as helium gas or a liquid such as liquid helium or liquid hydrogen. It may be.

  In this embodiment, the magnetic field generating member is an electromagnet (excitation coil), but a permanent magnet may be used as the magnetic field generating member, or an electromagnet and a permanent magnet may be used in combination. The magnetic field generating member may be any member that generates a magnetic field along the axial direction in the discharge space 6, and is not limited to a coil. For example, two magnets arranged at both axial ends of the ozone generator may be used. Further, the coil may be formed by using a thin film of a superconducting material instead of a superconducting material wire.

(Rotating mechanism)
The motor (rotating mechanism) 8 is connected to a power supply device (not shown), and rotates the inner electrode 2 in the circumferential direction (see arrows G in FIGS. 2 and 3). The rotation mechanism may be any mechanism that rotates at least one of the inner electrode and the outer electrode in the circumferential direction, and may rotate only the outer electrode, or may rotate both the inner electrode and the outer electrode. It may be allowed. Further, there may be no rotation mechanism.

(About the width of the discharge space)
Next, the width of the discharge space 6 will be described. The width of the discharge space 6 is the length in the radial direction of the discharge space 6. As shown in FIG. 3, the width dr of the discharge space 6 in the ozone generator 1 is equal to or greater than the maximum width of the electron swirling motion (cyclotron motion), and more specifically, the width dr is the electron swirling motion. Equal to maximum width. The maximum width of the swirling motion of the electrons is determined from (i) the maximum value of the magnetic flux density generated in the discharge space 6 by the solenoid-like excitation coil 5 and (ii) the maximum value of the electric field generated in the discharge space 6. .

  In this embodiment, the width of the discharge space 6 is constant at all positions in the circumferential direction. However, if the width of the discharge space is not constant, the minimum width of the discharge space is the maximum of the swirling motion of electrons. It only needs to be significantly greater.

  By flowing a direct current through the solenoid-like excitation coil 5, a static magnetic field along the axial direction is generated in the discharge space 6. Therefore, the electrons emitted from the cathode (inner electrode 2 in FIGS. 1 to 3) are subjected to a force (Lorentz force) perpendicular to both the direction of movement of the electrons and the magnetic field. As a result, the electrons perform a swiveling motion (cyclotron motion) in a direction perpendicular to the magnetic field. A circle 11 in FIG. 3 represents a trajectory of an electron swirling motion (cyclotron motion) when it is assumed that there is no electric field E and the electron is given an initial velocity.

The radius of the circle 11 in FIG. 3, that is, the radius (Larmor radius) r _L of the turning motion of the electrons is calculated according to the following equation.
r _L = (mv _⊥ ) / (eB) (Formula 1)
Here, v _⊥, m, e, and, B, respectively, of the electronic pivotal movement in a vacuum ⁽¹⁰ -4 Pa or less), the velocity component direction perpendicular to the magnetic field, electron mass, electric charge, And the magnetic flux density of the discharge space 6. Here, v _⊥ is a velocity component at a position closest to the cathode (the inner electrode 2 in the state of FIGS. 1 to 3 and the outer electrode 3 in the opposite state). Further, v _⊥ is an electron velocity component in the direction perpendicular to the magnetic field when electrons are emitted from the cathode.

  Actually, in the ozone generator 1, an electric field E is generated between the inner electrode 2 and the outer electrode 3. That is, the ozone generator 1 has an external force other than the magnetic field that acts on the electrons. As a result of the presence of the electric field E in addition to the magnetic field, the electrons drift in the circumferential direction. The drift motion refers to a motion in which the center (referred to as the swivel center) of the swiveling motion (refer to circle 11) of the charged particles moving in the magnetic field moves in a direction perpendicular to the magnetic field. The direction of the drift motion in the ozone generator 1 is a direction perpendicular to the magnetic field and the electric field, that is, the circumferential direction.

  As a result, the electrons are making a swiveling motion, and the swiveling center is in a drifting motion, so that the trajectory of one electron is a trajectory 10 (see FIGS. 2 and 3). Specifically, the electrons emitted from the inner electrode 2 that is the cathode move along the locus 10 toward the outer electrode 3 that is the anode, and then return to the cathode (inner electrode 2) side. During this movement, the electrons are also moving in the circumferential direction due to drift motion. Then, the electrons returning to the vicinity of the cathode (inner electrode 2) move again to the anode (outer electrode 3) side by repulsive force.

The speed of drift motion (drift speed) Vd is calculated according to the following equation.
Vd = (E × B) / B ² (Formula 2)
Here, Vd and E are a drift velocity and an electric field, respectively. In Equation 2, E, B, and Vd are vector quantities.

The maximum width of the electron swirl is the maximum distance between the cathode surface and the electron, and is equal to the diameter of the electron swirl (see circle 11). Then, the width dr of the discharge space may be set so as to satisfy the following expression.
dr ≧ 2r _L (Formula 3)

  From the viewpoint of preventing an increase in the size of the apparatus, it is desirable that dr be as small as possible. Therefore, it is desirable that the width of the discharge space 6 is equal to the diameter of the electron swivel motion. When the width dr of the discharge space does not satisfy Equation 3, that is, when the width of the discharge space is smaller than the diameter of the electron swirl, the electrons reach the anode during the swirl, and the electrons The movement distance in the discharge space becomes shorter (see the locus 10a in FIG. 2).

  Here, since the magnitude of the electric field is different between the vicinity of the cathode and the vicinity of the anode, the drift speed of electrons near the cathode and the drift speed of electrons near the anode are different. Therefore, the value of Vd in Equation 2 is not constant, and is large near the inner electrode 2 and small near the outer electrode 3.

Further, from the viewpoint of preventing the enlargement of the device and more surely preventing the contact between the electron and the anode, the width dr is larger than the diameter of the swivel movement of the electron to the extent that the device is not enlarged. It is desirable. For example, the width dr may be set so as to satisfy the following expression.
_{2r L <dr <(2r L} + r L / 10) ( Equation 4)

  As described above, an alternating current flows through the inner electrode 2 and the outer electrode 3, and the inner electrode 2 and the outer electrode 3 alternately change to one of the cathode and the anode with the passage of time. . In FIG. 1, as an example, the inner electrode 2 is a cathode and the outer electrode 3 is an anode, but the inner electrode 2 may be an anode and the outer electrode 3 may be a cathode.

  Moreover, in the ozone generator 1, since the superconducting magnet is used as the solenoid-like exciting coil 5, the magnetic flux density B is large. Under this condition, the period of change of the anode and cathode in both electrodes is larger than the period of cyclotron motion. For this reason, it can be considered that the polarity at both electrodes does not change with respect to the speed of the cyclotron motion and is stopped. Therefore, when designing the ozone generator 1, the change in the polarity of the electrode is not considered (for example, assuming that the polarity is fixed as shown in FIGS. The width of the discharge space 6 may be set using the following equation.

As described above, the width dr of the discharge space 6 can be appropriately set using Expressions 1 and 3. That is, the width dr is set using v _、, m, e, and B. Here, excluding constants m and e, the width dr is set based on v _⊥ and B. Further, v _⊥ is determined by the magnitude of the electric field E. That is, the width dr is determined based on (i) the magnitude (maximum value) of the electric field E generated in the discharge space 6 by the AC power supply 7a and (ii) the magnetic flux density B generated in the discharge space 6 by the DC power supply 7b. Is done.

For example, dr may be set to 0.1 [mm] or more under the following conditions.
(1) Magnetic flux density B by solenoid-like excitation coil: 1.7 [T]
(2) Maximum value of the electric field E between the electrodes: 2.17 × 10 ⁷ [V / m]

(Operation of ozone generator)
When an alternating current is passed through the ozone generator 1 configured as described above, that is, when an alternating high voltage is applied between the inner electrode 2 and the outer electrode 3, silent discharge occurs in the discharge space 6. Then, ozone is generated by the discharge in the discharge space 6. Specifically, a gas containing oxygen molecules (O ₂ ) is introduced into the discharge space 6, and electrons and oxygen molecules collide with each other due to the discharge in the discharge space 6. Oxygen molecules are generated. Then, ozone (O ₃ ) is generated by the combination of oxygen molecules and oxygen atoms.

  Further, the inner electrode 2 rotates during operation of the ozone generator 1. Specifically, in FIGS. 2 and 3, the direction of the drift motion is clockwise, whereas the inner electrode 2 rotates counterclockwise (see the arrow G direction in FIGS. 2 and 3).

  In the discharge space 6, if the center of rotation of the electrons can continue to drift for a long time along the circumferential direction, the number of collisions with oxygen molecules increases for one electron. As a result, since the number of oxygen molecules converted by one discharge increases, the generation efficiency of ozone is improved. And in the ozone generator 1, when the width | variety of the discharge space 6 is set appropriately, the rotation center of an electron can continue drift motion for a long time. Therefore, in the ozone generator 1, electrons emitted from the cathode (inner electrode 2 in FIGS. 1 to 3) in the discharge space 6 immediately after emission, the anode (outer electrode 3 in FIGS. 1 to 3). ) Is not reached. Therefore, electrons are not caught by the anode immediately after emission.

(About ozone generation method)
Next, the ozone generation method according to the present embodiment will be described using the ozone generator 1. In this ozone generation method, the ozone generator 1 is used.

  In this generation method, a gas containing oxygen molecules is introduced into the discharge space 6 and ozone is generated by the discharge in the discharge space 6 (ozone generation step). In this ozone generation step, the width dr of the discharge space 6 is equal to or greater than the maximum width of the swirling motion of electrons in the discharge space 6 (see Equation 3 above).

(effect)
Next, the effect of the ozone generator 1 and the ozone generation method according to the present embodiment will be described. The ozone generator 1 includes a cylindrical inner electrode 2, an outer electrode 3 disposed radially outside the inner electrode 2, and a discharge space 6 formed between the inner electrode 2 and the outer electrode 3 in the axial direction. And a solenoid-like excitation coil (magnetic field generating member) 5 for generating a magnetic field along the gas. A gas containing oxygen is introduced into the discharge space 6, and ozone is generated by the discharge in the discharge space 6. Is determined from (i) the maximum value of the magnetic flux density generated in the discharge space 6 by the solenoid-like excitation coil 5 and (ii) the maximum value of the electric field generated in the discharge space 6. It is over the maximum width of the swivel movement.

  According to this configuration, the discharge space 6 is formed between both electrodes (the inner electrode 2 and the outer electrode 3). Ozone is generated by introducing oxygen-containing gas into the discharge space 6. Electrons between the two electrodes are affected by the magnetic field generated by the solenoid-like excitation coil 5 and make a turning motion (cyclotron motion) by Lorentz force. Then, the center of rotation of electrons drifts in the circumferential direction.

  The maximum width of the cyclotron motion (maximum distance from the inner electrode) is determined from (i) the magnetic flux density generated by the magnetic field generating member and (ii) the magnitude of the electric field generated in the discharge space. When the width of the discharge space 6 is set to be equal to or greater than the maximum width of the turning motion, the electron turning motion and the drift motion are not hindered, and the electron moving distance becomes long. As described above, the collision frequency between oxygen molecules and electrons increases, and the ozone generation efficiency is reliably improved.

  The ozone generator 1 further includes a motor 8 that rotates the inner electrode 2 in the circumferential direction. Thereby, charges are not accumulated locally on the surface of the electrode (cathode), so that the discharge from the electrode surface is not disturbed locally, and the discharge is likely to occur.

  In the ozone generator 1, the outer electrode 3 is a cylindrical electrode arranged concentrically with the inner electrode 2. Thereby, the structure of an ozone generator can be simplified.

  In the ozone generator 1, the magnetic field generating member is a solenoid-like excitation coil 5 that is disposed concentrically with the inner electrode 2 and the outer electrode 3 on the radially outer side of the outer electrode 3. Thereby, a stable and uniform magnetic field can be formed in the discharge space 6.

  In the ozone generator 1, the solenoid-like excitation coil 5 includes a superconducting magnet. Thereby, the power consumption at the time of apparatus operation can be made low. In addition, since a strong magnetic field can be generated, the maximum width of the cyclotron motion can be reduced, and the apparatus can be miniaturized. In addition, a stable and uniform magnetic field can be easily formed in the discharge space 6.

  In addition, the ozone generation method according to the present invention includes a cylindrical inner electrode 2, an outer electrode 3 disposed radially outside the inner electrode 2, and a discharge space formed between the inner electrode 2 and the outer electrode 3. 6 is an ozone generation method using an ozone generator 1 having a solenoid-like excitation coil 5 for generating a magnetic field along the axial direction. A gas containing oxygen is introduced into the discharge space 6, and the discharge space 6 In the ozone generation step, in which the width of the discharge space 6 is (i) the maximum value of the magnetic flux density generated in the discharge space 6 by the solenoid-like excitation coil 5, and (ii) ) The maximum value of the electric field generated in the discharge space 6 and the maximum width of the swirling motion of electrons in the discharge space 6 determined from the maximum value.

  When the width of the discharge space 6 is set to be equal to or larger than the maximum width of the swirl movement by this method, the electron swivel movement and the drift movement are not hindered, and the electron movement distance becomes long. Therefore, the collision frequency between oxygen molecules and electrons increases, and the ozone generation efficiency is reliably improved.

  Moreover, in the ozone generator 1, by making a magnetic field into a static magnetic field, power consumption can be made low compared with the case where it makes an alternating magnetic field.

  In addition, since an alternating current flows between the inner electrode 2 and the outer electrode 3, the direction of the discharge current is periodically reversed. Therefore, compared with the case where a direct current is flowing, the collision frequency of an electron and an oxygen molecule increases, and ozone production efficiency improves.

  Although omitted in FIG. 1, the ozone generator 1 may be provided with a supply pipe for supplying a gas containing oxygen and a discharge pipe for discharging a gas containing ozone. Good. The ozone generator 1 may be provided with an oxygen supply device for supplying a gas containing oxygen to the discharge space 6.

(Second Embodiment)
Next, an ozone generator according to a second embodiment of the present invention will be described focusing on the differences from the above embodiment. In addition, about the part similar to said embodiment, the same code | symbol is attached | subjected to a figure and the description is abbreviate | omitted. FIG. 4 is a cross-sectional view showing the structure of an ozone generator according to the second embodiment of the present invention. In FIG. 4, the portions denoted by reference numerals 103, 106, and 110 correspond to the portions denoted by reference numerals 3, 6, and 10, respectively, in the above-described embodiment.

  In the ozone generator 101 according to the present embodiment, the outer electrode includes a plurality of cylindrical electrodes 103. Further, the axial direction of each of the plurality of columnar electrodes 103 is parallel to the axial direction of the inner electrode 2. In the present embodiment, no dielectric is disposed. The ozone generator may be configured in this way. A dielectric may be disposed, and in that case, the dielectric may be cylindrical or formed so as to surround each of the plurality of columnar electrodes 103.

  As described above, in the ozone generator 101 according to the present embodiment, the outer electrode includes the plurality of columnar electrodes 103, and the axial direction of each of the plurality of columnar electrodes 103 is parallel to the axial direction of the inner electrode 2. It is. Thereby, since a local electric field is formed between the inner electrode 2 and the outer electrode, discharge between both the electrodes is likely to occur, and the generation efficiency of ozone is further improved.

  Although the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

  For example, the ozone generator may be provided with a circuit for applying an exciting current to the solenoid-like exciting coil, whereby the direction of the exciting current flowing to the coil is set to the period of the alternating current flowing to both electrodes. You may make it switch together.

  In the above embodiment, one excitation coil is arranged outside the outer electrode. This excitation coil is composed of a plurality of divided coils, and the current flowing through each coil is different. Also good.

  Moreover, the discharge method of an ozone generator is not restricted to the discharge method like said embodiment. For example, ozone may be generated by the following discharge. (A) Creeping discharge: A planar electrode is disposed on the surface of a dielectric such as ceramics or glass (or an electrode is embedded in the dielectric), and a plurality of linear electrodes are disposed on the surface of the dielectric. Then, a potential difference is applied between the electrodes to accelerate electrons on the dielectric surface, and a gas containing oxygen is supplied thereto to generate ozone. (B) Fine metal line discharge: A glass container is placed between a rod-like anode metal and a cylindrical cathode metal surrounding it. Moreover, a metal thin wire is filled in the space between the glass container and the anode metal. Electric discharge is generated around a fine metal wire, and a gas containing oxygen is supplied to generate ozone.

  The ozone generator can be used, for example, under the optimum conditions (conditions in which the electron moving distance becomes long) as follows. Here, a case where an alternating electric field and an alternating magnetic field are generated in the apparatus will be described. (1) When the maximum value of electric field E (assumed as Es) and the maximum value of magnetic flux density B (assumed as Bs) are fixed as usage conditions of the apparatus: Es and Bs are obtained in advance The specifications of the electric field generating power source and the magnetic field generating power source are determined, and dr is determined based on Es and Bs.

  (2) As a use condition of the device, when the maximum value of the electric field E or the maximum value of the magnetic flux density B is not fixed and at least one of them is variable (adjustable): the value of dr Based on predetermined Es (maximum value of the electric field E) and predetermined Bs (maximum value of the magnetic flux density B), it is set in advance. A guide is provided in the adjustment mechanism so that the maximum value of the electric field E and the maximum value of the magnetic flux density B can be manually set to Es and Bs (for example, when the adjustment mechanism is a dial, Es is provided. And a special indication line at the position of the scale indicating Bs or Bs so that the dial lightly stops at the positions of Es and Bs). Alternatively, when the switch is operated, the maximum value of the electric field E and the maximum value of the magnetic flux density B may be automatically switched to Es and Bs. In addition, the user may be informed of the values of Es and Bs in advance so that the user can manually set the maximum value of the electric field E and the maximum value of the magnetic flux density B to Es and Bs. .

  The ozone generating apparatus and ozone generating method according to the present invention are used for the treatment of factory wastewater (treatment of circulating water, deodorization / decolorization of water discharged outside the factory), and sterilization in food production lines (collective in food factories) (Sterilization treatment).

Sectional drawing which shows the structure of the ozone generator which concerns on 1st Embodiment of this invention. Sectional drawing in the A-A 'position of FIG. Sectional drawing which expands and shows the principal part of FIG. Sectional drawing which shows the structure of the ozone generator which concerns on 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ozone generator 2 Inner electrode 3 Outer electrode 4 Dielectric 5 Solenoid excitation coil (magnetic field generating member)
6 Discharge space 7a AC power supply 7b DC power supply 8 Motor (rotating mechanism)

Claims (6)

A cylindrical inner electrode;
An outer electrode disposed radially outside the inner electrode;
A magnetic field generating member for generating a magnetic field along an axial direction in a discharge space formed between the inner electrode and the outer electrode;
A rotation mechanism for rotating at least one of the inner electrode and the outer electrode in the circumferential direction ,
A gas containing oxygen is introduced into the discharge space, ozone is generated by the discharge in the discharge space,
The width of the discharge space is determined from (i) a maximum value of magnetic flux density generated in the discharge space by the magnetic field generating member and (ii) a maximum value of electric field generated in the discharge space. An ozone generator characterized by having a width greater than or equal to the maximum width of electron swirl. The ozone generator according to claim 1, wherein the outer electrode is a cylindrical electrode arranged concentrically with the inner electrode. The outer electrode is composed of a plurality of cylindrical electrodes,
2. The ozone generator according to claim 1, wherein an axial direction of each of the plurality of columnar electrodes is parallel to an axial direction of the inner electrode. Wherein the magnetic field generating member, in the radially outer side of the outer electrode, characterized in that to the inner electrode and the outer electrode is a solenoidal excitation coil arranged concentrically, any one of claims 1 to 3 The ozone generator according to one item. The ozone generator according to any one of claims 1 to 4 , wherein the magnetic field generating member includes a superconducting magnet. Magnetic field generation for generating a magnetic field along the axial direction in a cylindrical inner electrode, an outer electrode arranged radially outside the inner electrode, and a discharge space formed between the inner electrode and the outer electrode An ozone generation method using an ozone generator having a member and a rotation mechanism that rotates at least one of the inner electrode and the outer electrode in a circumferential direction ,
Introducing an oxygen-containing gas into the discharge space, and generating ozone by discharge in the discharge space;
In the ozone generation step, the width of the discharge space is determined from (i) the maximum value of the magnetic flux density generated in the discharge space by the magnetic field generating member, and (ii) the maximum value of the electric field generated in the discharge space. The ozone generation method is characterized by being equal to or greater than the maximum width of the swirling motion of electrons in the discharge space.

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