JP2008142594A - Ultraviolet disinfection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultraviolet disinfection apparatus which can perform effective sterilization while maintaining high safety by utilizing ultraviolet light generated in an excimer lamp. <P>SOLUTION: An ultraviolet light source 13 is provided inside an ultraviolet treatment tank 11a where water to be treated flows. The inside of a discharge tube in the ultraviolet light source 13 is filled with a discharge gas for forming excimer molecules, and alternating voltage or pulse voltage is applied between electrodes, so that discharge is caused and ultraviolet light is generated, and the water flowing through the inside of the treatment tank 11a to be treated is sterilized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultraviolet disinfection apparatus that performs disinfection with ultraviolet light generated by an ultraviolet light source using a discharge gas that forms excimer molecules.

Conventionally, ultraviolet rays have been used to sterilize, disinfect, and decolorize water and sewage, deodorize and decolorize industrial water, bleach bleach pulp, and sterilize medical equipment. As a light source for generating such ultraviolet rays, a mercury lamp is mainly used because of its high ultraviolet ray generation efficiency (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 11-156352

  In such an apparatus using a mercury lamp, considering the leakage of mercury when the mercury lamp breaks, etc., it has a serious impact on the environment, so it is particularly difficult to apply it to water treatment equipment in waterworks. Met. However, devices other than mercury lamps have a short ultraviolet ray generation efficiency and a short lamp life, and are difficult to put into practical use.

  In recent years, excimer lamps have been used as ultraviolet light sources instead of mercury lamps. In the excimer lamp, when xenon, krypton, and argon are used as excitation media, ultraviolet rays having wavelengths of 172 nm, 146 nm, and 126 nm can be obtained, respectively.

  An object of the present invention is to provide an ultraviolet disinfection device that can perform effective sterilization while maintaining high safety by using ultraviolet rays generated by an excimer lamp.

  An ultraviolet disinfection apparatus according to the present invention includes an ultraviolet treatment tank through which water to be treated circulates, a protection tube provided in the ultraviolet treatment tank and made of a material capable of transmitting ultraviolet light, and provided in the protection tube. A dielectric container capable of passing through is filled with a discharge gas that forms excimer molecules, and an alternating voltage or a pulse voltage is applied between a pair of electrodes that are spaced apart from each other around the container. And an ultraviolet light source for generating ultraviolet light by causing electric discharge inside the container, and sterilizing by irradiating the water to be treated flowing in the ultraviolet treatment tank with the ultraviolet light generated by the ultraviolet light source.

  In the present invention, one or more halogens of fluorine, iodine, chlorine and bromine or a halogen compound supplying these halogens are filled as a discharge gas for forming excimer molecules filled in a container of an ultraviolet light source.

  In the present invention, as a discharge gas for forming excimer molecules filled in a container of an ultraviolet light source, any one or more rare gases of helium, argon, krypton, and xenon, and fluorine, iodine, chlorine, and bromine are used. A discharge gas mainly composed of a mixed gas containing any one or more halogens or a halogen compound supplying these halogens was filled.

  In the present invention, even if the halogen contained in the container of the ultraviolet light source installed in the ultraviolet treatment tank flows out due to damage or the like, the halogen concentration of the water to be treated in the ultraviolet treatment tank is It is advisable to provide a volume of water to be treated that is below the concentration that does not affect

  Further, in the present invention, even if the halogen contained in the container of the ultraviolet light source flows out due to breakage or the like, the sub tank can secure the volume of water to be treated so that the concentration of halogen in the water to be treated is less than the concentration that does not affect the human body. Or the structure provided with the water tank or the piping volume may be sufficient.

  Further, in the present invention, a blocking device that is provided in the treated water flow passage downstream from the ultraviolet treatment tank and blocks the downstream treated water flow passage when halogen contained in the container of the ultraviolet light source flows out due to damage or the like. You may prepare.

  In the present invention, a mechanism may be provided for isolating contaminated water when halogen contained in the container of the ultraviolet light source flows out due to breakage or the like.

  Furthermore, in this invention, what is necessary is just to set it as the structure provided with the water tank which stores the valve | bulb which interrupts | blocks the flow path to the downstream, and the blocked to-be-processed water as a mechanism which isolates contaminated water.

  According to the present invention, it is possible to drastically improve the performance of the ultraviolet sterilizer, such as maintaining high safety against device damage and effectively sterilizing.

  Hereinafter, an embodiment of an ultraviolet ray generator according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an embodiment in which an ultraviolet sterilizer is applied to a sewerage facility. In FIG. 1, 2 is a sewage adjustment pond, 3 is a first sedimentation basin, 5 is an aeration tank for aeration, 6 is a final sedimentation basin, 8 is a chlorine mixing basin, 11 is an ultraviolet disinfection device, and these are sewage in a sewage treatment plant. Are arranged and connected in series along the processing direction. In addition, 9 is a sludge concentration tank, 10 is a sludge dewatering machine, and the sludge concentration tank 9 is connected to the sludge discharge section of the first settling basin 3 and the final settling basin 6, and the outlet side is dewatered. It is connected to the entrance side of the machine 10.

  In the above-described configuration, sewage to be treated is first sent from the sewage adjustment basin 2 to the settling basin 3 where it is separated into the sewage in the supernatant and the excess sludge 4 in the sediment. The sewage from the supernatant is sent to the aeration tank 5, where it is treated with living organisms, medicines, etc. and flows into the final sedimentation basin 6. In the final sedimentation basin 6, the supernatant water is separated into the excess sludge 4 of the sediment, and the supernatant water is sent to the chlorine-mixing basin 8. Part of the excess sludge 4 is returned to the aeration tank 5 and the rest is sent to the concentration tank 9. The excess sludge 4 concentrated in the concentration tank 9 is further drained by a dehydrator (dryer) 10 and then regenerated into incinerators or fertilizers. The water 7 that has passed through the chlorine-mixing basin 8 is sterilized by the ultraviolet disinfection device 11 and then discharged into a river or the sea. The chlorine-mixing basin 8 is installed to disinfect by injecting chlorine when the ultraviolet disinfection device 11 is stopped due to regular inspection or the like.

  As shown in FIG. 2, the ultraviolet disinfection apparatus 11 introduces the water to be treated through a flow path 12 provided at the lower part of the partition wall 15 with the adjacent chlorine mixing basin 8, and distributes the water to be treated in an upward flow. It has an ultraviolet treatment tank 11a. An ultraviolet light source 13 is provided in the treatment tank 11a, and the water to be treated flowing in the upward flow in the treatment tank 11a is irradiated with ultraviolet rays to sterilize. The treated water after the sterilization treatment is discharged into the river (release groove) 14.

  Although not shown in detail, the ultraviolet light source 13 includes a protective tube and a discharge tube. That is, the protective tube is made of a material that can transmit ultraviolet rays, and protects the discharge tube provided therein from solids in the water to be treated. The discharge tube is provided in a protective tube, and includes a cylindrical container made of a dielectric material that can transmit ultraviolet rays, and a pair of electrodes that are arranged apart from each other around the container (usually both ends). The container is filled with a discharge gas that forms excimer molecules, and an alternating voltage or a pulse voltage is applied between the pair of electrodes to cause discharge inside the container and generate ultraviolet light. .

  As a discharge gas for forming excimer molecules filled in a vessel serving as a discharge tube of the ultraviolet light source 13, when one or more halogens of fluorine, iodine, chlorine and bromine or a halogen compound supplying these halogens is filled, Good.

  Further, as this discharge gas, one or more rare gases of helium, argon, krypton, and xenon, and one or more halogens of fluorine, iodine, chlorine, and bromine or a halogen compound that supplies these halogens are included. The discharge gas which has the mixed gas containing as a main component is filled.

  In the ultraviolet disinfection (sterilization) apparatus 11 configured as described above, ultraviolet light is generated by excimer discharge in the ultraviolet light source 13 and irradiated to the water to be treated, so that the water to be treated can be effectively sterilized. it can. Further, even if the ultraviolet light source 13 is damaged, the impact on the environment is small, and high safety can be maintained. That is, the discharge gas filled in the discharge tube of the ultraviolet light source 13 is fluorine added to prevent dental caries or iodine, chlorine and bromine used for disinfection of drinking water, so the lamp breaks and the gas flows out. But the risk is low and does not matter.

  Of course, if these concentrations become extremely high, the human body will be affected, but the treated water that has passed through the ultraviolet disinfection device 11 is discharged into the river 14 and the like, so it is diluted with a large amount of water and there is no problem. In other words, when a conventional mercury lamp breaks and mercury flows out, its toxicity is so high that it cannot be compared, so it is dangerous to discharge it into rivers, but the above-mentioned fluorine, iodine, chlorine, bromine, etc. It can be diluted enough by being discharged into a river and has little impact on the environment.

  Next, an embodiment when applied to sterilization of drinking water facilities and drinking water will be described with reference to FIGS.

  FIG. 3 shows a case where the present invention is applied to a water purification facility, wherein 17 is a landing well, 18 is a rapid stirring pond, 19 is a flock formation pond, 20 is an activated carbon adsorption pond, 31 is an ultraviolet disinfection device, 21 is a rapid filtration pond, 22 Is a reservoir and these are arranged and connected in series along the processing flow of the water treatment facility.

  In the above configuration, raw water that is to be treated flows into the landing well 17. The raw water is sent from the landing well 17 to the rapid stirring pond 18 and the floc forming pond 19 where it is coagulated and settled, and the supernatant water is sent to the activated carbon adsorption pond 20 and filtered. The filtered water is sent to the ultraviolet disinfection device 31 and sterilized (sterilized and inactivated). Furthermore, after chlorine injection, it is sent to the rapid filtration pond 21, filtered, and stored in the distribution reservoir 22. And it is bottled and supplied as distribution water or drinking water as tap water.

  The ultraviolet disinfection device 31 may have a configuration equivalent to that of the ultraviolet disinfection device 11 shown in FIG. 2, but since it is finally supplied as tap water, the configuration shown in FIG. 4 may be used.

  FIG. 4 shows a unit-type ultraviolet disinfection device 31 used in a water treatment system for simply using groundwater or surface water as drinking water. In FIG. 4, reference numeral 23 denotes a sedimentation tank, in which water to be treated introduced from the lower side surface flows upward toward a discharge port provided on the upper side surface, and sediment is discharged from the bottom. A filter 25 is provided with a cylindrical activated carbon filter 26 provided concentrically therein. And the to-be-processed water introduced from the upper part is filtered with the activated carbon filter 26 with the pipe line which has the flowmeter 24, Then, it discharges | emits from the discharge port of a lower side surface toward the next stage. 28 is a reactor for ultraviolet irradiation (ultraviolet treatment tank), and the water to be treated introduced from the lower side surface through the pipe line having the ultraviolet transmittance meter 27 flows upward toward the discharge port provided on the upper side surface. .

  In the reactor 28, an ultraviolet light source 13 comprising a protective tube 30 and a discharge tube 29 is provided in a vertical direction, and irradiates the water to be treated flowing in an upward flow with ultraviolet rays to sterilize.

  The ultraviolet light source 13 has basically the same configuration as the ultraviolet light source described with reference to FIG. 2 and includes a protective tube 30 and a discharge tube 29. The protective tube 30 is made of a material capable of transmitting ultraviolet rays, and protects the discharge tube 29 provided therein from solid matter in the water to be treated. The discharge tube 29 is provided in the protective tube 30, and includes a cylindrical container made of a dielectric material that can transmit ultraviolet rays, and a pair of electrodes that are spaced apart from each other around the container (usually both ends). Have The container is filled with a discharge gas that forms excimer molecules, and an alternating voltage or a pulse voltage is applied between the pair of electrodes to cause discharge inside the container and generate ultraviolet light. .

  The same applies to the discharge gas that forms excimer molecules filled in a container that becomes the discharge tube 29 of the ultraviolet light source 13, and one or more halogens of fluorine, iodine, chlorine, and bromine, or halogens that supply these halogens. A compound, or one or more rare gases of helium, argon, krypton, and xenon, and one or more halogens of fluorine, iodine, chlorine, and bromine, or a halogen compound that supplies these halogens, A discharge gas whose main component is a mixed gas containing is filled.

  A sub-tank 32 having a predetermined volume is branched and connected to a pipe line connected to the outlet of the reactor 28, and a shut-off device 33 such as a gate valve is provided in a downstream portion thereof.

  In the above configuration, raw water (treated water) such as groundwater flows into the sedimentation tank 23 by a pump (not shown). In the sedimentation tank 23, a flocculant is added depending on the water quality, and impurities are agglomerated and removed. The supernatant water from the settling tank 23 measures the flow rate with the flow meter 24 and then flows into the filter 25. In the filter 25, water-soluble impurities that cannot be coagulated are adsorbed by the activated carbon filter 26. The water that has passed through the filter 25 measures the transmittance with the ultraviolet transmittance meter 27 and then flows into the reactor 28 for ultraviolet irradiation.

  Inside the ultraviolet irradiation reactor 28, an ultraviolet lamp is applied as the ultraviolet light source 13, and discharges by receiving electric power from an unillustrated ultraviolet lamp power source to emit ultraviolet rays. The ultraviolet light emitted from the ultraviolet light source 13 is irradiated to the water to be treated in an upward flow through a protective tube 31 made of a material that transmits ultraviolet rays, and is sterilized (sterilized and inactivated) to be used as tap water. Bottled and supplied as distribution or drinking water.

  Here, even if the halogen contained in the container of the ultraviolet light source 13 installed in the reactor (ultraviolet treatment tank) 28 flows out due to breakage or the like, the concentration of halogen in the water to be treated in the reactor 28 is high. The volume of water to be treated is set so that the concentration does not affect the human body. That is, the volume of the reactor 28 for ultraviolet irradiation is set to be equal to or higher than the volume at which the concentration of halogen and its compound does not affect the human body even if the halogen flows out due to damage or the like.

  Further, when the volume of the reactor 28 for ultraviolet irradiation is small, a sub-tank 32 connected to a downstream pipe line or a water tank (not shown) is prepared, or the pipe volume is increased, so that the halogen flows out due to damage or the like. Alternatively, the halogen concentration may be configured to be equal to or less than a concentration that does not affect the human body. In other words, even if the halogen flows out due to breakage, etc., the sub-tank or water tank or pipe volume that can secure the volume of the water to be treated is less than the concentration that does not affect the human body. .

  In addition, when halogen flows out due to breakage or the like, a shut-off device 33 such as a gate valve may be immediately closed to prevent the outflow to the outside, and a mechanism for isolating contaminated water may be provided. That is, when a blocking device 33 is provided in the treated water flow path downstream from the ultraviolet treatment tank 28 and the halogen flows out due to breakage or the like, the blocking device 33 immediately blocks the downstream treated water flow path, thereby causing contaminated water to flow. Prevent expansion.

  The mechanism for isolating the contaminated water may have a configuration including a valve for blocking the downstream flow passage and a water tank for storing the blocked water to be treated.

  In the case of fluorine, which is a drug added to prevent dental caries, the concentration that does not affect the human body is 1.5 mg / l or less of the WHO drinking water content guideline. In the case of halogen chlorine or a compound thereof which is also a drug used for disinfecting drinking water, the concentration is 100 mg / l or less. Further, in the case of halogen iodine or a compound thereof, which is also an agent used for sterilization of pool water or emergency drinking water such as disasters, the concentration that does not affect the human body is a concentration of 5 mg / l or less. Further, in the case of halogen bromine or a compound thereof, which is also a drug used for disinfection of sewage and pool water, the concentration that does not affect the human body is a concentration of 45 mg / l or less. However, in the case of bromine as a bromine compound, the concentration that does not affect the human body is a concentration of 0.01 mg / l or less.

  According to the ultraviolet ray generator according to the present invention, the risk of mercury spillage when the lamp is broken can be avoided. In addition, since UV light sources using iodine, chlorine, bromine, etc., which are fluorine added to prevent tooth decay and chemicals used for disinfecting drinking water, are used as discharge gas, the danger is that the lamp will break and the gas will flow out. The degree is low.

  Even if halogen contained in the discharge tube of the ultraviolet light source flows out due to damage, etc., if the reactor volume is such that the halogen concentration does not affect the human body, the risk associated with gas outflow is minimized. Become. In addition to the volume of the UV irradiation reactor, if a sub-tank or water tank is prepared, or if the piping volume is sufficiently secured, the halogen concentration of the water to be treated will not affect the human body even if the halogen flows out due to damage. The risk of gas outflow can be minimized.

  Furthermore, if a shut-off device such as a gate valve is provided, it is possible to prevent the outflow / expansion of the halogen having a concentration that affects the human body when the halogen flows out due to damage or the like. In this case, it is preferable to provide a mechanism for isolating water contaminated by the halogen outflow to isolate halogen having a concentration that affects the human body.

It is a processing system diagram showing the case where the ultraviolet disinfection device according to the present invention is applied to a sewage facility. It is sectional drawing which shows the structural example of the ultraviolet disinfection apparatus used in FIG. It is a processing system diagram showing the case where the ultraviolet disinfection device according to the present invention is applied to a water supply facility. It is a block diagram which shows the structural example of the ultraviolet-ray disinfection apparatus used in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 31 Ultraviolet disinfection apparatus 11a, 28 Ultraviolet processing tank 13 Ultraviolet light source 29 Discharge tube 30 Protection tube 32 Subtank 33 Shut off device

Claims (8)

An ultraviolet treatment tank in which the water to be treated is distributed;
A protective tube made of a material that is provided in the ultraviolet treatment tank and is capable of transmitting ultraviolet rays;
A discharge vessel for forming excimer molecules is filled in a dielectric container capable of transmitting ultraviolet rays, and an AC voltage or pulse is applied between a pair of electrodes arranged around the container and spaced apart from each other. An ultraviolet light source that generates ultraviolet light by causing a discharge inside the container by applying a voltage;
An ultraviolet disinfection apparatus characterized in that the water to be treated flowing in the ultraviolet treatment tank is sterilized by irradiating with ultraviolet rays generated by an ultraviolet light source.   A discharge gas for forming excimer molecules filled in a container of an ultraviolet light source is filled with one or more halogens of fluorine, iodine, chlorine and bromine or a halogen compound supplying these halogens. Item 4. The ultraviolet disinfection device according to Item 1.   As a discharge gas for forming excimer molecules filled in a container of an ultraviolet light source, any one or more rare gases of helium, argon, krypton and xenon, and any one or more of fluorine, iodine, chlorine and bromine 2. The ultraviolet ray generator according to claim 1, which is filled with a discharge gas whose main component is a mixed gas containing halogen or a halogen compound supplying the halogen.   The UV treatment tank has a halogen concentration below the concentration that does not affect the human body even if the halogen contained in the container of the UV light source installed in the UV treatment tank flows out due to damage or the like. The ultraviolet disinfection device according to any one of claims 1 to 3, further comprising a volume of water to be treated.   Even if the halogen contained in the container of the ultraviolet light source flows out due to damage, etc., the sub-tank or water tank or piping volume that can secure the volume of the water to be treated will be less than the concentration that does not affect the human body. The ultraviolet disinfection device according to any one of claims 1 to 3, further comprising:   It is provided in a treated water flow passage downstream from the ultraviolet treatment tank, and includes a blocking device that blocks the downstream treated water flow passage when halogen contained in the container of the ultraviolet light source flows out due to damage or the like. The ultraviolet disinfection apparatus according to any one of claims 1 to 3.   4. The ultraviolet disinfection device according to claim 1, further comprising a mechanism for isolating contaminated water when halogen contained in the container of the ultraviolet light source flows out due to damage or the like.   4. A mechanism for isolating contaminated water, comprising a valve for blocking a downstream flow path and a water tank for storing blocked water to be treated. UV disinfection equipment.

Images