JP2015054277A - Water treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve treatment efficiency of water to be treated by a simple structure.SOLUTION: A water treatment apparatus (20) for treating water to be treated includes a pipe part (30) in which the water to be treated exists, bubble supply means (40) which supplies bubbles into the pipe part (30), and electric discharge means (50) which generates a discharge reaction in the bubbles. The bubbles relatively move in the pipe part (30) with respect to the water to be treated.

Description

  The present invention relates to a water treatment apparatus for treating various types of water.

  2. Description of the Related Art Conventionally, a water treatment apparatus is known in which a discharge reaction is caused in oxygen and treated water such as ballast water is treated with ozone generated by the reaction. In such a water treatment apparatus, various developments have been made in order to improve or stabilize the treatment efficiency of water to be treated.

  For example, Patent Document 1 discloses an inline mixer in which water to be treated flows, a blade plate for turning the water to be treated flowing into the inline mixer into a swirl flow, and ozone that generates ozone by causing a discharge reaction in oxygen. A water treatment device is disclosed that includes a generator and a mushroom-shaped protrusion provided on the inner surface of an in-line mixer. The mushroom-shaped protrusion is provided on the downstream side of the blade in the in-line mixer. The ozone generated by the ozone generator is supplied into the swirling flow formed by the blades. Then, ozone (bubbles) is directed to the inner surface of the in-line mixer by the swirling flow, collides with the mushroom-shaped protrusions and bursts. At this time, a cavitation shock wave is generated. Treatment of the water to be treated (sterilization of the water to be treated, killing microorganisms, etc.) is efficiently performed by this shock wave.

International Publication No. 2006/137121

  In the water treatment apparatus of Patent Document 1, the treatment efficiency of the treated water is improved or stabilized by using a shock wave. However, in order to generate shock waves, in addition to the blades for forming a swirl flow in the water to be treated, mushroom-shaped projections for rupturing ozone bubbles are required, which complicates the structure of the device. It is difficult to avoid.

  An object of the present invention is to improve the treatment efficiency of water to be treated with a simple structure.

  As means for solving the above-mentioned problems, the present invention provides a water treatment apparatus for treating water to be treated, a pipe part in which the water to be treated is present, and a bubble supply means for supplying bubbles into the pipe part. And a discharge means for causing a discharge reaction in the bubbles, and providing a water treatment device in which the bubbles move relative to the water to be treated in the tube portion.

  In the present invention, among the hydroxyl radicals (.OH) generated by the occurrence of a discharge reaction in the bubbles supplied to the water to be treated, those present on the surface of the bubbles come into contact with the water to be treated. Water is processed. And in this invention, since a bubble moves relatively with respect to to-be-processed water within a pipe part, since to-be-processed water contacts the whole surface of a bubble reliably, to-be-processed water is hydroxy on the surface of a bubble. It is effectively processed by radicals. Therefore, according to the present invention, improvement or stabilization of the treatment efficiency of the water to be treated can be achieved with a simple structure.

  In this case, it is preferable that the tube portion has a narrow portion and a wide portion having a width larger than the narrow portion, and the bubble supply means is connected to the wide portion.

  By providing the narrow portion, the water to be treated and the bubbles can be efficiently contacted. By providing the bubble supply means in the wide part, the installation space for the bubble supply means can be secured.

  In the present invention, the discharge means includes a pair of electrodes and a power source applied between the pair of electrodes, and the bubble supply means includes a gap between the pair of electrodes, and the tube portion And a valve disposed in the passage and configured to prevent the water to be treated from flowing between the pipe portion and the pair of electrodes.

  In this way, since the inflow of the water to be treated from the tube portion between the pair of electrodes is prevented, a decrease in discharge efficiency due to the infiltration of the water to be treated between the pair of electrodes is prevented. .

  Further, in the present invention, the bubble supply means has a plurality of bubble supply units that supply the bubbles to the tube portion, and the discharge means discharges the bubbles supplied from the plurality of bubble supply units. It is preferable to have a plurality of discharge units that cause a reaction.

  In this way, the treatment efficiency of the water to be treated is further improved.

  In the present invention, it is preferable that at least an inner surface of the tube portion is formed of a substance having a bond dissociation energy larger than an oxidation energy of a hydroxy radical generated in the bubbles by the discharge reaction.

  In this way, since the hydroxyl radical does not react with the inner surface of the pipe part, in other words, the oxidation energy of the hydroxy radical is used for the treatment of the water to be treated without being used for the oxidation of the inner surface of the pipe part. Both suppression of corrosion or deterioration of the inner surface of the pipe part and improvement of the treatment efficiency of the water to be treated are achieved.

  Moreover, in this invention, it is preferable that the said pipe part is provided in piping connected to the tank which stores a ballast water, and is used in order to process the ballast water which flows through the said piping.

  According to the present invention, the ballast water can be stored in the tank, or the ballast water can be stored in the tank simply by connecting the pipe of the water treatment device to the pipe. Ballast water is effectively treated both when it is stored and when it is discharged from the tank.

  As described above, according to the present invention, the treatment efficiency of water to be treated can be improved with a simple structure.

It is a figure which shows the outline of a structure of the ballast water treatment apparatus of 1st embodiment of this invention. It is a figure which shows the outline of a structure of the water treatment apparatus of 1st embodiment of this invention. It is a flowchart which shows the drive operation | movement of the ballast water treatment apparatus of FIG. It is a figure which shows the modification of the water treatment apparatus of FIG. It is a figure which shows the modification of the water treatment apparatus of FIG. It is a figure which shows the outline of a structure of the water treatment apparatus of 2nd embodiment of this invention.

(First embodiment)
The ballast water treatment apparatus 10 provided with the water treatment apparatus 20 of 1st embodiment of this invention is shown by FIG. The ballast water treatment apparatus 10 includes a tank 12 for storing water to be treated, a pipe 14 connected to the tank 12, a pump 16 provided in the pipe 14, and a plurality of water treatment apparatuses 20 connected to the pipe 14. It has.

  The tank 12 stores treated water, and is disposed at the bottom of a ship (not shown).

  One end of the pipe 14 is connected to the tank 12 and extends from there to the outside of the ship, that is, toward the sea side.

  The pump 16 feeds water to be treated (ballast water) into the tank 12 and sends out the water to be treated in the tank 12 to the outside of the ship.

  In the present ballast water treatment device 10, the water to be treated (in this embodiment, in this embodiment) both when the water to be treated is sent into the tank 12 and when the water to be treated is discharged from the tank 12. Ballast water) and killing microorganisms in the water to be treated.

  A specific structure of the water treatment device 20 of the present embodiment will be described with reference to FIG.

  The water treatment device 20 includes a tube portion 30 where water to be treated is present, a bubble supply unit 40 constituting bubble supply means for supplying bubbles containing oxygen into the tube portion 30, and a discharge that causes a discharge reaction in the bubbles. And a discharge unit 50 constituting the means. In FIG. 2, the water to be treated flows in the pipe portion 30 from the upstream side (right side in FIG. 2) to the downstream side (left side in FIG. 2).

  The pipe part 30 has a cylindrical shape, and both ends thereof are connected to the pipe 14. The tube portion 30 includes a cylindrical narrow portion 32 having a relatively small inner diameter and a cylindrical wide portion 34 having a relatively large inner diameter. The wide portion 34 and the narrow portion 32 are connected via a tapered portion 34a. The wide portion 34 is provided on the upstream side of the narrow portion 32. In this embodiment, when the ballast water which is to-be-processed water is stored in the tank 12, and when to-be-processed water is discharged | emitted from the tank 12, the flow of the to-be-processed water in the pipe part 30 becomes reverse direction. Therefore, the narrow portion 32 is provided on both sides (both upstream and downstream) of the wide portion 34 via the tapered portion 34a.

  The bubble supply unit 40 includes a supply pipe 42 for supplying bubbles into the pipe portion 30, a pump 44 provided in the supply pipe 42, and an opening / closing valve 46 provided in the supply pipe 42.

  The supply pipe 42 is made of an insulating material. One end of the supply pipe 42 is connected to the wide portion 34. That is, the bubbles B are supplied into the pipe part 30 (wide part 34) through the passage formed in the supply pipe 42.

  The pump 44 sends a gas (for example, air) containing oxygen into the pipe portion 30 through the passage.

  The on-off valve 46 is provided in the vicinity of the end of the supply pipe 42 on the side where the supply pipe 42 and the wide portion 34 are connected. The on-off valve 46 allows passage of gas when the valve is opened, while preventing passage of water to be treated when the valve is closed.

  In the present embodiment, the bubble supply unit 40 supplies the treated water to the treated water so that bubbles B having a diameter larger than the inner diameter of the narrow portion 32 and smaller than the inner diameter of the wide portion 34 are supplied to the wide portion 34. The flow rate of the gas to be controlled is controlled.

  The discharge unit 50 includes a pair of electrodes 52 and a power source 54.

  The pair of electrodes 52 is composed of a bar-shaped or plate-shaped counter electrode facing each other in a state of being separated from each other. The pair of electrodes 52 are fixed to the inner peripheral surface of the supply pipe 42 across the passage. Therefore, bubbles are supplied from the pump 44 through the pair of electrodes 52 into the tube portion 30. In the present embodiment, the pair of electrodes 52 are fixed on the upstream side (upper side in FIG. 2) in the gas flow with respect to the portion of the supply pipe 42 where the on-off valve 46 is provided. Note that one of the pair of electrodes 52 may be a cylindrical electrode, and the other may be a rod-shaped electrode disposed in a cylindrical electrode in a state of being separated from the cylindrical electrode. In this case, the cylindrical electrode is fixed to the inner peripheral surface of the supply pipe 42.

  The power supply 54 applies a DC voltage that causes a plasma discharge reaction to the gas supplied between the pair of electrodes 52 to the pair of electrodes 52 via wiring. The voltage applied to the pair of electrodes 52 may be a pulse voltage.

  As shown in FIG. 2, the water treatment device 20 of the present embodiment further includes a first sensor 62, a second sensor 64, and a control unit 66.

  The first sensor 62 is a sensor that detects the pressure in the pipe on the upstream side (the side on which the pair of electrodes 52 is provided) of the supply pipe 42, that is, the pressure of the gas. It is.

  The 2nd sensor 64 is a sensor which detects the pressure in the pipe part 30, ie, the pressure of to-be-processed water.

  The controller 66 controls the opening / closing of the opening / closing valve 46 according to the detection values of the sensors 62 and 64. Specifically, the driving operation of the ballast water treatment apparatus 10 including the control content of the control unit 66 will be described with reference to FIG. 3 together with the mechanism for treating the water to be treated. Hereinafter, the case where treated water is stored in the tank 12 first will be described.

  First, the on-off valve 46 is closed (step ST10).

  Then, a gas containing oxygen is supplied between the pair of electrodes 52 by the pump 44 (step ST11). In this state, a voltage is applied between the pair of electrodes 52 (step ST12). As a result, a plasma discharge reaction occurs in the gas between the pair of electrodes 52. Specifically, oxygen contained in the gas is supplied with electrons (e) and reacts as shown in the following reaction formula (1) to generate oxygen radicals (.O).

O ₂ + 2e → 2 · O + 2e (1)
In addition, step ST11 and step ST12 may be performed in the reverse order to the above, or may be performed simultaneously.

  Thereafter, the pump 16 is driven (step ST13), and the water to be treated (ballast water) is sent to the tank 12 through the pipe 14.

  In this state, the control unit 66 determines whether or not the value of the first sensor 62 is larger than the value of the second sensor 64 (step ST14). As a result, if the value of the first sensor 62 is larger than the value of the second sensor 64, the on-off valve 46 is opened (step ST15).

Then, bubbles B containing oxygen radicals are supplied into the wide portion 34. At this time, as shown in the following reaction formula (2), oxygen radicals react with water (H ₂ O) of water to be treated to generate hydroxy radicals (.OH).

・ O + H ₂ O → 2.OH (2)
The hydroxy radical generated by the reaction of the above reaction formula (2) has the highest reactivity among the molecular species called active oxygen and has the strongest oxidizing power. Very effective. This hydroxy radical is also present on the surface of the bubble B. That is, when the hydroxyl radical existing on the surface of the bubble B comes into contact with the water to be treated, the water to be treated is treated.

  The bubbles B move in the water to be treated to the downstream side (from the wide portion 34 to the narrow portion 32 side). Specifically, the bubbles B travel at a speed slower than the flow rate of the water to be treated. In other words, the water to be treated moves toward the tank 12 while passing the bubbles B.

  At this time, the diameter of the bubble B supplied to the wide portion 34 is larger than the inner diameter of the narrow portion 32, that is, the size of the bubble B is such that the inside of the narrow portion 32 is blocked. In the part 32, the water to be treated is surely brought into contact with the entire surface of the bubble B when passing the bubble B. Therefore, the water to be treated is effectively treated with the hydroxyl radicals on the surface of the bubbles B.

  Thereafter, when the value of the first sensor 62 becomes smaller than the value of the second sensor 64, the control unit 66 closes the on-off valve 46 (step ST16). In this way, the water to be treated is prevented from flowing into the supply pipe 42 from the pipe section 30 and reaching between the pair of electrodes 52. Therefore, the occurrence of problems with the discharge unit 50 is prevented. Specifically, when the water to be treated flows between the pair of electrodes 52, the impedance between the pair of electrodes 52 increases, and the plasma discharge reaction is less likely to occur in the gas passing between the pair of electrodes 52. The pair of electrodes 52 are immersed in the water to be treated (ballast water) to prevent the pair of electrodes 52 from being corroded.

  Except that when the water to be treated (ballast water) is stored in the tank 12 and when the water to be treated is discharged from the tank 12, the direction in which the water to be treated in the pipe 30 flows is opposite to each other. Since it is the same, description is abbreviate | omitted when discharging to-be-processed water from the tank 12. FIG.

In addition, ultraviolet rays are also generated during the discharge reaction of the above reaction formula (1). In addition, ozone (O ₃ ) is generated by the reaction of oxygen radicals generated during the reaction represented by the reaction formula (1) with surrounding oxygen. Furthermore, for example, hydrogen peroxide (H ₂ O ₂ ) may be generated by a reaction between oxygen radicals and water. All of these have a bactericidal effect and a killing effect of microorganisms and the like. Thus, the water to be treated is treated with ultraviolet rays, ozone and hydrogen peroxide in addition to the hydroxy radicals.

Here, as shown in FIG. 4, at least the inner surface 30 a of the tube portion 30 is a substance having a bond dissociation energy larger than the oxidation energy (120.6 kcal / mol) of the hydroxyl radical existing on the surface of the bubble B. It is preferable to be formed. Examples of such a substance include titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ). The bond dissociation energy of titanium oxide is 145 kcal / mol and that of silicon oxide is 150 kcal / mol. In addition, the pipe part 30 itself may be composed of the above-mentioned substance, or a coating layer made of the above-mentioned substance is provided on the inner peripheral surface of the pipe part 30 by thermal spraying or coating, and this coating layer constitutes the inner surface 30a. May be.

  In this way, the hydroxy radical does not react with the substance constituting the inner surface of the tube part 30. In other words, the oxidation energy of the hydroxyl radical is used for the treatment of the water to be treated without being used for the oxidation of the substance constituting the inner surface of the pipe part 30. For this reason, both suppression of corrosion or deterioration of the inner surface of the pipe part 30 and improvement of the treatment efficiency of the water to be treated are achieved.

  In addition, it is preferable that the inner surface (surface on which the water to be treated comes into contact) on the downstream side of the portion where the on-off valve 46 is provided in the supply pipe 42 is also formed of the above substance. The same applies to the following embodiments.

  Further, in the present embodiment, an example in which the bubble supply unit is configured by a single bubble supply unit 40 and the discharge unit is configured by a single discharge unit 50 is shown, but the present invention is not limited thereto. For example, as shown in FIG. 5, the bubble supply means is composed of a plurality of (four in FIG. 5) bubble supply units 40a to 40d, and the discharge means is a plurality of (four in FIG. 5) discharge units 50. You may be comprised from. Since the configuration of each discharge unit 50 is the same as described above, the description thereof is omitted.

  In this aspect, the plurality of bubble supply units 40a to 40d are configured of a first bubble supply unit 40a to a fourth bubble supply unit 40d. Each of the bubble supply units 40 a to 40 d has a supply pipe 42, a pump 44, and a valve 43 provided in the supply pipe 42. In FIG. 5, the on-off valve 46, the first sensor 62, the second sensor 64, and the control unit 66 are omitted, and the pair of electrodes 52 are connected to the supply pipe 42 and the wide part 34 on the inner peripheral surface of the supply pipe 42. The example fixed to the edge part of the side to which is connected is shown.

  The supply pipe 42 of the first bubble supply unit 40 a is connected to a predetermined part of the wide part 34. The supply pipe 42 of the second bubble supply unit 40b is spaced from the supply pipe 42 of the first bubble supply unit 40a in the axial direction of the wide portion 34, in other words, in the state in which the wide portion 34 extends. It is connected. The supply pipe 42 of the third bubble supply unit 40 c is separated from the supply pipe 42 of the first bubble supply unit 40 a in the circumferential direction of the wide portion 34, in other words, separated in a plane perpendicular to the extending direction of the wide portion 34. In this state, it is connected to the wide portion 34. The supply tube 42 of the fourth bubble supply unit 40d is connected to the wide portion 34 in a state of being separated from the supply tube 42 of the first bubble supply unit 40a in the axial direction and the circumferential direction of the wide portion 34.

  The valve 43 is configured to open when the flow rate of the gas delivered from the pump 44 reaches a predetermined value. The opening / closing of the valve 43 may be performed by a controller 48 that can control the opening / closing of the valve 43. The controller 48 is connected to each valve 43.

  In the present embodiment, the bubbles B are supplied from the bubble supply units 40 to the tube portion 30 so that the bubbles B supplied from the bubble supply units 40 to the wide portion 34 are sequentially introduced into the narrow portion 32 while being separated from each other. The interval for supplying B, that is, the opening timing of each valve 43 is set. For example, the bubbles B are alternately supplied from the pair of bubble supply units 40 facing each other in the direction orthogonal to the direction in which the water to be treated flows (the axial direction of the wide portion 34), and are separated from each other in the axial direction of the wide portion 34. From the pair of air bubble supply units 40, the air bubbles B are supplied at a timing at which the air bubbles B are kept apart from each other without being merged in consideration of the axial distance between them and the flow rate of the water to be treated.

  Any one or two of the first bubble supply unit 40a to the fourth bubble supply unit 40d may be omitted.

  In this way, in a state where the bubbles B are separated from each other, that is, a state where a plurality of bubbles B are combined and the contact area between the bubbles B and the water to be treated is sufficiently secured without reducing the surface area. Since each bubble B is sequentially introduced into the narrow portion 32, the interval between the bubbles B in the narrow portion 32 is narrower than when the bubbles B are supplied only by the single bubble supply unit 40. Therefore, the treatment efficiency of the water to be treated in the narrow portion 32 is improved.

(Second embodiment)
The water treatment apparatus 20 of 2nd embodiment of this invention is demonstrated referring FIG. In the second embodiment, only the parts different from the first embodiment will be described, and the description of the same structure, operation, and effect as in the first embodiment will be omitted.

  In 2nd embodiment, the pipe part 30 is arrange | positioned with the attitude | position in which the axial direction becomes parallel to a perpendicular direction. The tube portion 30 includes a narrow portion 32, a wide portion 34 having a cross-sectional area in the direction orthogonal to the axial direction larger than that of the narrow portion 32, and a tapered portion connecting the narrow portion 32 and the wide portion 34. 34a. The tube portion 30 is arranged in such a posture that the wide portion 34 is located below and the narrow portion 32 is located above the wide portion 34. The wide portion 34 has a cylindrical peripheral wall 34b, and the lower end of the peripheral wall 34b is closed by a bottom wall 34c orthogonal to the axial direction of the peripheral wall 34b. That is, the pipe part 30 has a shape in which the upper part 32a of the narrow part 32 (the end part opposite to the side connected to the wide part 34) is open to the outside.

  In the present embodiment, the bubble B supplied by the bubble supply unit 40 rises in the water to be treated that remains in the narrow portion 32 by buoyancy acting on itself. In addition, since the specific gravity of to-be-processed water is larger than the specific gravity of the bubble B, the to-be-processed water in the narrow part 32 is not conveyed by the bubble B to the upper part 32a of the narrow part 32, but the bubble B which rises Flows relatively downwardly through the space between and the inner peripheral surface of the narrow portion 32.

  Therefore, also in the present embodiment, in the narrow portion 32, the water to be treated is reliably in contact with the entire surface of the bubbles B, so that the water to be treated is effectively treated with the hydroxy radicals on the surface of the bubbles B.

  Although the water treatment apparatus 20 of this embodiment can also be applied to the ballast water treatment apparatus 10 as in the first embodiment, batch processing of a certain amount of water to be treated stored in the pipe section 30 is possible. Especially suitable for. In this case, the tank 12, the pipe 14, and the pump 16 are omitted.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in each of the above-described embodiments, the example in which the water treatment device 20 treats the ballast water is shown. However, the water treatment device 20 can treat various treated water in addition to the ballast water. For example, the water to be treated includes wastewater from various factories and business establishments, water from a water and sewage treatment plant, and drinking water.

  The on-off valve 46 is a check valve that allows gas that has passed between the pair of electrodes 52 to pass through the pipe portion 30 and prevents the inflow of water to be treated from the pipe portion 30 to between the pair of electrodes 52. There may be. In this case, the sensors 62 and 64 and the controller 66 are omitted. The number of bubble supply units 40 may be five or more. The narrow part and the wide part of the tube part 30 are not necessarily cylindrical. In the first embodiment, the pipe part 30 of the water treatment device 20 may be provided inside the pipe 14. Further, the water treatment device 20 may be provided in the tank 12.

DESCRIPTION OF SYMBOLS 10 Ballast water treatment apparatus 12 Tank 14 Piping 16 Pump 20 Water treatment apparatus 30 Pipe part 30a Inner surface 32 Narrow part 34 Wide part 40 Bubble supply unit (bubble supply means)
42 Supply pipe 43 Valve 44 Pump 46 On-off valve 50 Discharge unit (discharge means)
52 Pair of electrodes 54 Power supply 62 First sensor 64 Second sensor 66 Control section B Bubble

Claims (6)

A water treatment device for treating water to be treated,
A pipe portion where the treated water exists;
A bubble supply means for supplying bubbles into the tube;
A discharge means for causing a discharge reaction in the bubbles,
The water treatment apparatus in which the bubbles move relative to the water to be treated in the pipe portion. The water treatment apparatus according to claim 1,
The tube part has a narrow part and a wide part having a width larger than the narrow part,
The bubble supply means is a water treatment apparatus connected to the wide part. The water treatment device according to claim 1 or 2,
The discharging means includes a pair of electrodes and a power source applied between the pair of electrodes,
The bubble supply means
A passage including a gap between the pair of electrodes and connected to the tube portion;
A valve that is disposed in the passage and prevents the water to be treated from flowing from the pipe portion between the pair of electrodes;
A water treatment apparatus comprising: The water treatment apparatus according to any one of claims 1 to 3,
The bubble supply means has a plurality of bubble supply units for supplying the bubbles to the pipe part,
The water discharge apparatus, wherein the discharge means includes a plurality of discharge units that cause the discharge reaction to occur in the bubbles supplied from the plurality of bubble supply units. The water treatment apparatus according to any one of claims 1 to 4,
A water treatment apparatus, wherein at least an inner surface of the tube part is formed of a substance having a bond dissociation energy larger than an oxidation energy of hydroxy radical generated in the bubbles by the discharge reaction. The water treatment device according to any one of claims 1 to 5,
A water treatment apparatus, wherein the pipe part is provided in a pipe connected to a tank for storing ballast water, and is used for treating ballast water flowing in the pipe.

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