Patent Application
20140054242
The present invention is related to a liquid-treating apparatus which treats to-be-treated liquid electrochemically, in particular a liquid-treating apparatus which treats the liquid by generating plasma.
A conventional liquid-treating apparatus using a high-voltage pulse discharge is described in, for example, Patent Document 1.
The sterilizing apparatus 1 shown in
Similarly, Patent Document 6 A proposes a method for purifying liquid wherein the liquid is boiled and vaporized to form bubbles and the vaporized substance (generate plasma) is ionized within the bubbles to form ions and the ion species in the plasma are penetrated and diffused in the liquid. Patent Document 6 describes that, in order to generate plasma, high-voltage pulses having a maximum voltage of about 1 kV to 50 kV, repeated frequencies of 1 kHz to 100 kHz and a duration of 1 μs to 20 μs, are applied to an electrode pair of high-voltage electrodes.
Another conventional liquid-treating apparatus is described in Patent Document 2. Patent Document 2 discloses that a liquid-treating apparatus described in this document can reduce an applied voltage by interposing bubbles, which are supplied from outside, between electrodes in liquid, whereby power consumption can be reduced. Similar techniques are disclosed in Patent Documents 3, 4, and 5.
Patent Document 1: JP 2009-255027 A
Patent Document 2: JP 2000-93967 A
Patent Document 3: JP 2003-62579 A
Patent Document 4: JP 2010-523326 A
Patent Document 5: JP 3983282 B
Patent Document 6: JP 2007-207540 A
However, there was a problem that generation efficiency of plasma was low in the above-described conventional apparatuses, requiring a long time of period for treating liquid. Further, when the plasma is generated in bubbles formed by vaporization of the liquid, it is necessary to input high electrical power to vaporize the liquid since the electrical power was lost in the liquid, which requires a large-scale power supplying apparatus. Specifically, the power supplying apparatus is required to have ability of supplying electricity power of 4000 W or more in order to vaporize water, considering the loss.
The present invention solves the problem and provides a liquid-treating apparatus and a liquid-treating method which enable liquid to be treated in a short period of time and/or with a low power by efficient plasma generation.
A liquid-treating apparatus of the present invention includes:
a first electrode of which at least a part is placed in a treatment vessel that is to contain liquid,
a second electrode of which at least a part is placed in the treatment vessel,
a bubble-generating part which generates a bubble in the liquid when the liquid is contained in the treatment vessel, such that at least surface where conductor is exposed, of a surface of the first electrode which surface is positioned in the treatment vessel, is positioned within the bubble,
a gas-supplying apparatus which supplies gas in an amount necessary for the bubble generation from the outside of the treatment vessel, and
a power supply which applies voltage between the first electrode and the second electrode.
A plasma-generating method of the present invention includes:
applying voltage between a first electrode and a second electrode using a power supply, at least a part of the first electrode being positioned in liquid contained in a treatment vessel and at least a part of the second electrode being positioned in the liquid, and
supplying gas to a bubble-generating part positioned in the liquid to generate a bubble in the liquid,
wherein the bubble is generated such that at least surface where conductor is exposed, of a surface of the first electrode which surface is positioned in the liquid, is positioned within the bubble, and
plasma is generated within the bubble by the application of voltage.
The present invention enables plasma to be generated efficiently and thereby enables the liquid to be treated with low power and/or in a short period of time.
Embodiments of the present invention will be described with reference to the drawings.
In
A dimension of the treatment vessel 109 is not limited particularly. For example, the dimension of the treatment vessel 109 may be one having a capacity of 0.1 liters to 1000 liters.
In case where the liquid-treating apparatus is incorporated in a household appliance, the volume of a unit consisting of the power supply and the pump is preferably 1000 cm3 to 5000 cm3. Such a volume is preferably obtained by designing a cubic of which length×width×height is 100 mm×100 mm×100 mm to 171 mm×171 mm×171 mm. Alternatively, the unit consisting of the power supply and the pump may be of rectangular parallelepiped or another shape. When the dimension (that is, the volume) of the unit consisting of the power supply and the pump which is included in the liquid-treating apparatus is too large in the household appliance, the household appliance itself becomes large. Since the liquid-treating apparatus of the present invention can generate plasma efficiently, the liquid can be treated with the power supply which is small enough to be received by the unit of the above volume.
When the gas is continued to be supplied from the opening portion of the first electrode 104 in the to-be-treated water 110 using the above configuration, a bubble 106 is formed in the to-be-treated water 110. The bubble 106 is a columnar bubble having a dimension such that the gas within the bubble covers the opening portion of the first electrode 104, that is, the opening portion of the first electrode 104 is positioned within the bubble 106. Therefore, the first electrode 104 also functions as a bubble-generating part in the first embodiment. The end face of the opening portion of the first electrode 104 is not covered by the insulator 103 as shown in
In the present specification, “the first electrode (or the surface of the first electrode) does not contact directly with liquid (to-be-treated water)” means that the surface of the first electrode does not contact with liquid as a large mass in the treatment vessel. Therefore, when the bubble is generated from the bubble-generating part with the surface of the first electrode wet (strictly, with the surface of the first electrode in contact with the liquid), a state where the surface is covered with the gas within the bubble may be achieved. Such state is included in the state where “the first electrode does not contact directly with liquid.”
Next, the operation of the liquid-treating apparatus of the present embodiment is described.
Firstly, the gas is supplied by the pump 105 into the to-be-treated water 110 from one opening portion of the first electrode 104 which portion is positioned in the treatment vessel. The flow rate of the gas is, for example, 0.5 litters/min to 2.0 litters/min. In the to-be-treated water 110, the columnar bubble 106 is formed such that the gas inside the bubble 106 covers the opening portion of the first electrode 104 as described above. The bubble 106 is a single and large bubble which is continuous over a certain distance (20 mm or more in the illustrated embodiment) from the opening portion of the first electrode 104. In other words, the supply of gas gives the state where the vicinity of the opening portion of the first electrode 104 is positioned within the bubble 106 and covered with the gas within the bubble 106. The bubble 106 of which internal gas covers the end face of the opening portion of the first electrode 104 is defined in the liquid by a gas-liquid interface which is not “close”, and contacts with the insulator 103 around the opening portion of the first electrode 104. As described above, the conductor is exposed only at the end face of the opening portion in the external surface of the first electrode 104, and therefore the external surface of the first electrode 104 is isolated from the to-be-treated water 110 by the bubble 106 and the insulator 103 as a result of generation of the bubble 106. The inside surface (inner peripheral surface) of the first electrode 104 is covered by the gas supplied during the formation of the gas 106 and does not contact directly with the to-be-treated water 110.
It is preferable that the vicinity of the opening portion of the first electrode 104 is positioned within the bubble 106, that is, continuously covered with the gas within the bubble 106 during the application of voltage between the first electrode 104 and the second electrode 102. However, when the supplied amount (flow rate) of the gas is small, and even if the gas is continuously supplied, the vicinity of the opening portion of the first electrode 104 may not be positioned within the bubble 106 resulting in direct contact with the to-be-treated water 110. The presence or absence of such contact can be observed by taking a photograph of the vicinity of the first electrode 104 every 0.1 ms to 0.5 ms during the supply of gas, using a high-speed camera. Further, it is possible to know a frequency of contact between the first electrode 104 and the liquid by taking photographs with use of a highly sensitive camera while the gas is supplied continuously for 1 seconds to 30 seconds, and determining an electrode coverage by the following formula. Whether the surface where the conductor is exposed, of the first electrode is positioned within the bubble or not is judged by visual observation of the photographs. The gas is supplied in the liquid-treating apparatus of the present invention including this embodiment such that the electrode coverage is preferably 90% or more, more preferably 94% or more.
Electrode coverage (%)=[(number of images (photographs) wherein the conductor-exposed surface of the first electrode is positioned within the bubble)/(total number of images (photographs) taken)]×100
Next, the voltage is applied between the first electrode 104 and the second electrode 102. The pulsed voltage is applied to the first electrode 104 with the second electrode 104 grounded. For example, a pulsed voltage has a peak voltage of 4 kV, a pulse duration of 1 μs and a frequency of 30 kHz. The power is, for example, 200 W. Plasma is generated in the vicinity of the first electrode 104 by the application of the voltage between the first electrode 104 and the second electrode 102. Although the plasma is spread over the entire of the bubble 106, concentrated plasma 107 is formed particularly in the vicinity of the first electrode 104. It is found that the plasma is also formed in the inside of the first electrode (the inner peripheral portion of the cylindrical first electrode) and not only the tip portion but the entire electrode is effectively used. Further, the observation by the high-speed camera shows a relatively smooth surface of the bubble as shown in
The distance between the first electrode 104 and the second electrode 102 is not limited particularly. For example, it is not necessary to limit the electrode distance to 1 mm to 50 mm as described in Patent Document 1. The plasma can be generated even if the distance between the electrodes is more than 50 mm.
Further, the first electrode 104 and the second electrode 102 are not required to be opposed to each other. The position of the second electrode 102 is not limited as long as at least a part of the second electrode 102 contacts with the to-be-treated water 110 in the treatment vessel 109. This is because the entire to-be-treated water functions as an electrode as a result of contact of the second electrode 102 with the to-be-treated water 110. In other words, it is considered that the entire surface of the to-be-treated water 110 which contacts with the bubble 106 functions as the electrode when viewed from the first electrode 104.
Further, a frequency of the pulsed voltage is not limited particularly. For example, the plasma can be sufficiently generated by application of pulsed voltage of 1 Hz to 30 kHz. On the other hand, it is needless to say that the voltage is not determined only by the performance of the power supply, and it is determined by balance with the impedance of a load. There is an advantage that lifetime of the electrode is improved by applying a bipolar pulsed voltage, that is, by applying positive voltage and negative voltage alternately. In this embodiment, the power supply which is capable of outputting a voltage of 6 kV without a load is used, and a voltage of 4 kV can be applied actually, under the condition that the loads including the electrodes are connected thereto as described above. In this manner, the plasma can be formed with less loss of the voltage in the present embodiment.
In the present embodiment, the inner diameter of the first electrode 104 was 0.4 mm and the outer diameter was 0.6 mm. However, the plasma can be formed when the inner diameter is 0.07 mm to 2.0 mm and the outer diameter is 0.1 mm to 3.0 mm. Further, the dimension (the length) of the first electrodes 104 in the treatment vessel 109 is not limited particularly. For example, in the treatment vessel 109, the first electrode 104 having the inner and outer diameters of the above-mentioned ranges may have a length of 0.1 mm to 25 mm. In this embodiment, the length of the portion of the first electrode 104 which portion is positioned in the treatment vessel 109 is about 10 mm. When the portion of the first electrode 104 which portion is positioned in the treatment vessel 109 is small, the bubble 106 formed near the opening portion of the first electrode 104 cannot spread in a direction toward the wall of the treatment vessel 109 (collides with the wall) and thereby an area of a gas-liquid interface is small, resulting in tendency of reduction in the plasma generation amount. However, plasma is generated as long as the first electrode 104 is positioned in the treatment vessel 109. In this way, tolerance for the size of the electrodes is also wide in the liquid-treating apparatus of the present embodiment.
Then, the effect on the to-be-treated liquid given by the liquid-treating apparatus of the present embodiment will be described. In the present embodiment, an aqueous indigocarmine solution was used as the model of the to-be-treated liquid. Indigocarmine is a water-soluble organic substance, and is often used as a model for polluted-water treatment. A concentration of the aqueous indigocarmine solution used in the present embodiment was 10 mg/liter, and the volume of the to-be-treated water 110 was 250 milliliters.
As described above, OH radicals, N radicals, N2 radicals, H radicals and O radicals are generated in the present embodiment. These radicals acts on indigocarmine and cut the binding in the molecule to decompose the indigocarmine molecule. As is generally known, an oxidation potential of the OH radical is 2.81 eV, being greater than those of ozone and chlorine. Thus, the OH radicals can decompose not only indigocarmine, but many organic substances. In addition, the bond energies between the O radical and carbon and between the N radical and carbon are 1076 kJ/mol and 750 kJ/mol respectively, being much larger than the C—C bond energy of 618 kJ/mol and the C—H bond energy of 338 kJ/mol. Therefore, they contribute significantly to the decomposition of indigocarmine molecules. Further, N ions and N2 ions are generated by the plasma due to the generation of the bubble 106 by air supply, and these ions collide with indigocarmine molecules. Since the collision of these ions weakens the inter-molecule bond of the indigocarmine molecule, the decomposition effects of the OH radicals, the O radicals, and N radicals are made much larger.
The decomposition degree of the indigocarmine molecule can be evaluated by absorbance of an aqueous solution thereof. It is generally known that blue of the aqueous indigocarmine solution is decolorized when the indigocarmine molecules are decomposed and the solution become transparent when the molecules are decomposed completely. This is because the absorption wavelength of the carbon double bond (C═C) is 608.2 nm and the C═C bond is cleaved by the decomposition of the indigocarmine molecule whereby light of 608.2 nm is not absorbed. Thus, the degree of decomposition of the indigocarmine molecules was evaluated by measuring the absorbance of light having a wavelength of 608.2 nm using an ultraviolet-visible light spectrophotometer.
In
In the conventional liquid-treating apparatus of Comparative Example 1, columnar electrodes of tungsten having an outer diameter of 0.16 mm were used as the first electrode 104 and the second electrode 102 and the end faces of these electrodes was opposed to each other with a distance of 2 mm in the indigocarmine solution. The results of treatment by this apparatus are shown by the black squares. Further, the black triangles show, as Comparative Example 2, the change in absorbance during the treatment wherein the same electrode configuration was employed and fine bubbles (diameter of about 0.3 mm) were continuously supplied between the first electrode 104 and the second electrode 102 from a nozzle provided separately. In these comparative examples, the power supplied to the first electrode 104 was set to 200 W similarly to the liquid-treating apparatus of the present embodiment.
As shown in
Consideration of the conventional liquid-treating apparatuses as the comparative examples is as follows. It is considered that, in Comparative Example 1 wherein two electrodes are opposed with a distance of 2 mm, the amount of generated radicals is small since the plasma is generated in space of about 0.04 mm3 between the electrodes. According to the detailed analysis of the inventors, it is found that bubbles are generated near the surfaces of the two opposed electrodes during the discharge in Comparative Example 1, and the plasma is generated inside the bubbles. Moreover, the bubbles are not always formed. When the bubbles are moved by buoyancy, the plasma is accordingly extinguished. Then, the formation of fresh bubbles and the generation of plasma inside the bubbles are repeated. That is, although it is possible to generate plasma by narrowing the distance between the electrodes and applying pulsed voltage, the plasma is not efficiently generated because of the intermittent generation of plasma and a small space in which the plasma is generated. For this reason, the decomposition time of the indigocarmine molecules is considered to be longer.
In the case where the bubbles are supplied through a nozzle from the outside, more bubbles are continuously interposed between the electrodes. Therefore, it is considered that more plasma is generated compared to the case where the bubbles are not supplied. However, the liquid-treating apparatus of the present embodiment can generate more plasma compared to the case where the bubbles are supplied from the outside, and gives pronounced effect of reducing the time for decomposing indigocarmine molecules to one third. It is considered that this is because the gas is continuously supplied to the to-be-treated water 110 at a relatively large flow rate from the end portion of the first electrode 104. That is, it is considered that this is because the end face of the surface of the first electrode 104 which surface is positioned in the liquid (the conductor-exposed surface) is covered with the gas within the bubble 106 by the supply of a large amount of gas during the discharge between the first electrode 104 and the second electrode 102, whereby the first electrode 104 does not contact directly with the to-be-treated water 110. It is considered that, as a result, a current path (or discharge path) consisting of only liquid is not formed in the treatment vessel, whereby a high voltage is applied to the gas-liquid interface without loss of voltage, leading to generation of much plasma. Detail will be described in a second embodiment.
In this embodiment, iron was used as a material for the second electrode 102 and the first electrode 104. These electrodes may be formed of tungsten, copper or aluminum or the like. Further, the insulator provided on the outer peripheral surface of the first electrode 104 may be formed by thermally spraying yttrium oxide. Yttrium oxide has higher resistance against plasma compared to titanium oxide. Therefore, the use of yttrium oxide gives the effect of increasing the electrode lifetime.
[Effect (Treatment with a Low Power)]
In the present embodiment, the change in time required for decolorizing blue of the aqueous indigocarmine solution was observed while the supplied power was varied. The flow rate was set to 2000 ml/min in the liquid-treating apparatus of the configuration as described above. Further, pulsed voltage having a peak voltage of 4 kV, a pulse duration of 500 μs, a frequency of 100 Hz and a power of 30 W was applied between the first electrode 104 and the second electrode 102, and the time required for decomposing the indigocarmine molecules in the aqueous solution was determined. Similarly, pulsed voltage having a pulse duration of 500 μs, a frequency of 100 Hz and a power of 6 W was applied between the first electrode 104 and the second electrode 102, and the time required for decomposing the indigocarmine molecules in the aqueous solution was determined. The results are shown in
As shown in
Further, when 30 W or 6 W was tried to be supplied in the treating apparatus of the configuration used in Comparative Example 1, the flash boiling phenomenon was not observed and the discharge did not occur since the power was not able to be input at all (6 W and 30 W was not able to be set), resulting in failure or plasma generation.
The liquid-treating apparatus of the present invention enables the liquid to be treated with a small power. Accordingly, the liquid-treating apparatus of the present invention does not require high power (4000 W or more) such as required in the apparatuses described in Patent Document 1 and Patent Dcoument 6. Specifically, the power supply may be one of which maximum output capacity is more than 0 W and less than 1000 W in the liquid-treating apparatus of the present invention and the power over 1000 W is not required to be supplied. Such power can be obtained from the power supply of the household electric appliance. Thus, the liquid-treating apparatus according to the present invention is suitable for being incorporated into a household electric appliance in terms of power, and the unit consisting of the power supply and the pump can be made so small that it has the above-mentioned volume (1000 cm3 to 5000 cm3).
Further, in the case where the power of the above-mentioned range is supplied, the discharge between the electrodes is corona to glow discharge. When the plasma is generated by the glow discharge, the power consumption is lower compared with abnormal glow discharge and arc discharge and a large current is not required, and therefore the capacity of the power supply is made smaller and the deterioration of the electrode is reduced. For these reasons, there is an advantage that the price of the apparatus and the maintenance cost are reduced.
A plasma-generating method is known wherein an electrode to which voltage is applied is not positioned in liquid and is positioned above a liquid level, a grounding electrode is positioned in the liquid, and plasma is generated on the liquid level by conducting discharge. This method and the present invention are in common in that the electrode to which voltage is applied is not in direct contact with the liquid. However, when the plasma is generated according to this method, ozone is generated. Ozone is an undesirable product. Further, in this method, there is a tendency that the area of the plasma in contact with the liquid becomes smaller, resulting in generation of a small amount of OH-radical. Further, there is a limit to the increase in the amount of the generated OH radical by increasing the number of the electrodes. This is because, even if a plurality of electrodes are arranged to increase the area of plasma, the distance between the electrode and the liquid level is narrow to be about 1 mm and the volume of plasma generated in the space therebetween is small, and the interface between the plasma and the water is thin. In addition, there is also a drawback that this method is difficult to be employed in a home appliance wherein the liquid level changes. The time for decolorization was about 45 minutes in experiment wherein 250 milliliters aqueous indigocarmine solution of 10 mg/L was treated applying power of 200W with use of an electrode having a diameter of 1 mm. It is considered that this means that this method is poor in sterilization efficiency compared to the discharge obtained by using the liquid-treating apparatus of the present invention. In addition, when the power is 30 W or 6 W, the decolorization speed is too slow to determine.
Air of 2000 ml/min was supplied from the pump. Further, the second electrode 102 was grounded and pulsed voltage having a peak voltage of 4 kV, a pulse duration of 1 μs, a frequency of 30 kHz and a power of 200 W was applied to the first electrode 104.
The graph of
The decolorization time is not so changed, when the distance “d” is −2 mm or less. Further, when the distance “d” is −4 mm or less, the length of the interface between the gas and the water is rather long to make discharge difficult. Therefore, the plasma is difficult to decompose water, resulting in reduction in amount of the OH radicals. Thus, this is not to say that it is favorable that the end face of the first electrode 104 is simply farther away from the to-be-treated water 110. The optimal distance “d” depends on the amount of gas supplied and the dimension and shape of the first electrode.
Further, in the case where the position of the end face of the opening portion of the first electrode was positioned outside the end face of the insulator at the start of the voltage application and was moved relatively more inside than the end face of the insulator after the generation of plasma, the decolorization time was not long even if the distance “d” after the movement was −4 mm or less. It is considered that this is because the plasma generation was started in the state where the opening portion of the first electrode 104 was positioned within the bubble 106 and covered with the gas in the bubble 106 that was formed in the to-be-treated water 110. That is, it is considered that this is because the volume of the plasma protruded in the water when “d” was changed to −4 mm or less after the generation of the plasma, was not changed from the volume of the plasma protruded in the water when “d” was −2 mm, and therefore the amount of the radicals was not so changed.
Further, when the first electrode 104 is moved relatively to the insulator 103 to obtain a minus value of “d”, there is an advantage of stable discharge with a small and stable voltage loss since the first electrode 104 is hardly wet by water. The relative movement of the first electrode 104 to the insulator 103 may be performed by moving the insulator 103, or by moving the first electrode 104.
The bubble state was observed with a high-speed camera while varying the distance “d”. As shown in
Air of 2000 ml/min was supplied from the pump. Further, the second electrode 202 was grounded and pulsed voltage having a peak voltage of 4 kV, a pulse duration of 1 μs, a frequency of 30 kHz and a power of 200 W is applied to the first electrode 204.
In the present embodiment, the state of bubble was observed with a high-speed camera. As shown in
As shown in
Further, in a variation of the present embodiment, the influence on the treatment time of the to-be-treated liquid was observed by using the insulator 203 of cylindrical alumina ceramics which is movable relative to the electrode 204 and changing the positional relationship between the end face of the first electrode 204 and the end face of the insulator 203 similarly to the second embodiment. In this variation, the end face of the first electrode 204 is positioned about 2 mm inwardly from the end face of the insulator 203, and the absorbance of the to-be-treated liquid is determined while the plasma is generated.
The results are shown in
The present embodiment has been described as the embodiments, but the present invention shall not be limited to the embodiments described above. In the above embodiments, the embodiment wherein the to-be-treated liquid is water has been described as an example and the embodiment wherein the aqueous indigocarmine solution is used as a model has been described. The same effects can be obtained even if the liquid is alcohol, sea water, or an aqueous solution wherein a chemical is dissolved.
In the above embodiment, a technique of generating the bubble has been described wherein the first electrode is made tubular (more specifically, cylindrical) and the gas is supplied by the gas supplying apparatus to the first electrode so as to supply the gas through the opening portion of the first electrode into the liquid. In another embodiment, the bubble-generating part may be provided independently from the first electrode. The bubble-generating part generates a bubble such that the surface where the conductor is exposed, of the surface of the first electrode which surface is positioned in the liquid, is covered by the gas within the bubble, that is, the surface where the conductor is exposed is positioned within the bubble. Such a bubble is formed by appropriately selecting a flow rate of the gas sent to the bubble-generating part, a size of the bubble-generating part (for example, an inner diameter of the bubble-generating part if the bubble-generating part is cylindrical) and the position of the bubble-generating part. When the gas-generating part is placed under the first electrode, the gas in the bubble easily covers the surface of the first electrode since the bubble formed in the liquid moves from bottom to top by buoyancy.
In the embodiments described above, the first electrode is made tubular and the outer peripheral surface of the first electrode is covered with insulator such that the outer peripheral surface of the first electrode is not exposed to the liquid. Therefore, the area to be covered by the gas in the bubble is only the vicinity of the opening portion (end face) of the first electrode. Therefore, the effect of the present invention can be obtained relatively with ease by using the first electrode of such configuration. In another embodiment of the present invention, the first electrode may not be covered with the insulator. In this case, the gas-generating part is provided such that the entire of the surface portion of the first electrode which portion is positioned within the liquid is covered with the gas. Alternatively, in another embodiment, the insulator may cover a part of the outer peripheral surface of the first electrode. In this case, the surface portion of the first electrode, which portion is not covered with the insulator, is required to be covered with the gas within the bubble.
In the above embodiments, a circulation pump for circulating the to-be-treated water is provided. The circulation pump is not necessarily needed. In the plasma-generating apparatus according to the present invention, the generation of bubble causes the circulation of the liquid naturally in the treatment vessel and the circulation of the liquid is also facilitated by the generation of microbubbles. Thus, the entire to-be-treated water can be treated by plasma even if the circulation pump is not provided.
In the embodiments described above and other embodiments, a film for preventing the electrode from corroding may be formed on the first electrode. The corrosion protection film is formed by selecting material and thickness in consideration of the material for electrode and the voltage applied to the electrode, such that the discharge between the first electrode and the second electrode is not hindered. The effect of the present invention can be obtained even if such a film is formed on the conductor surface of the first electrode and the embodiment having such a film is covered by the claims of the present application.
The liquid-treating apparatus of the present invention is suitable for: liquid treatment by decomposition of the chemical presenting in the liquid, the destruction of microorganism or sterilization or the like, and can be used together with various products, particularly electrical products, or can be used being incorporated into electrical products. The electrical products include water purification apparatuses, air conditioners, humidifiers, ballast water treatment systems for ships, washing machines for electric razors, washing machines and dishwashers. The water purification apparatuses, the air conditioners, the humidifiers, the washing machines for electric razors and dishwashers may be for home use. The liquid-treating apparatus of the present invention can be operated using a power supply for a household appliance since the apparatuses can treat the liquid with a low power.
The liquid-treating apparatus of the embodiment of the present invention is useful as a water purification apparatus and so on for, for example, waste water treatment and so on.
101, 201 Pulsed power supply
102, 202 Second electrode
103, 203 Insulator
104, 204 First electrode
105, 205 Pump
106, 206 Bubble
107, 207 High-concentration plasma
108, 208 Circulation pump
109, 209 Treatment vessel
110, 210 To-be-treated water
111, 211 Microbubble
| Number | Date | Country | Kind |
|---|---|---|---|
| 2011-110169 | May 2011 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2011/007272 | 12/26/2011 | WO | 00 | 10/22/2013 |
