JP2013163159A - Cleaning apparatus and washing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning apparatus 1 and a washing method that can prevent the re-scattering of a contaminant, control the yield of contaminated water, and improve the safety of a worker who performs a cleaning operation in the cleaning apparatus 1 and washing method in which washing water Ww is jetted to a contaminant that adheres to a structure 20 or the like to be flushed.SOLUTION: A cleaning apparatus 1 includes: a washing water purification mechanism that purifies washing water Ww; a jet spray nozzle 3 that jet sprays the washing water Ww; a recovery mechanism 4 that recovers a first contaminated water Wt1 containing the contaminant that is jet sprayed from the jet spray nozzle 3; a filter 5 that removes the contaminant from the first contaminated water Wt1; and a circulation mechanism 6 that circulates a second contaminated water Wt2 that has passed the filter 5 to the upstream side of the filter 5 again, wherein the circulation mechanism 6 includes a reverse osmosis membrane 7, and the cleaning apparatus 1 includes a resupply circuit 8 that supplies pure water Wp from the circulation mechanism 6 to the washing water purification mechanism 2 through the reverse osmosis membrane 7.

Description

  The present invention relates to a cleaning apparatus and a cleaning method for cleaning contaminants attached to structures and the like.

  Due to the effects of the earthquake on March 11, 2011, a large amount of radioactive material was released from nuclear power plants and adhered to buildings such as houses. And in order to reduce the health damage to the inhabitants, decontamination work for removing radioactive substances adhering to buildings and the like is required. At present, in this decontamination work, a method (high pressure washing) in which high-pressure water (for example, water pressure is 4.9 to 9.8 MPa) is sprayed on a roof or wall surface of a building and the radioactive material is washed away is employed. This high-pressure cleaning has been conventionally performed even in a nuclear power plant (for example, see Patent Right 1). This high-pressure cleaning can remove radioactive substances adhering to structures, etc., reduce the amount of surrounding radiation, and reduce health damage to workers and residents working in the reactor. It was.

  However, the above decontamination work by high pressure cleaning has several problems. First, there is a problem that a large amount of contaminated water is generated. This is because a large amount of water is used for high-pressure washing. The collection, transportation, and treatment of this contaminated water is very time consuming and financial.

  Secondly, there is a problem that radioactive materials may re-scatter. This is because the water pressure of the washing water sprayed on the wall surface is high. In particular, in conventional decontamination work, contaminated water containing radioactive substances may adhere to an operator holding a hose or the like that injects cleaning water, and the safety of the operator is sufficiently secured. I could not say.

  Third, it has been difficult to ensure the safety of workers who perform decontamination work. Even if a large amount of radioactive material is contained in the contaminated water, the water itself absorbs radiation, and a simple dosimeter such as a Geiger counter should be used to evaluate the risk of contaminated water. Because it was not possible. In particular, when contaminated water or spray thereof adheres to the worker, radioactive substances will adhere directly, which may cause external exposure. Similarly, when spray of contaminated water or the like is sucked by an operator, internal exposure may occur. In addition, in order to accurately evaluate the risk of radioactive substances in liquids such as contaminated water, the unit of becquerel is used to measure the effects of radioactive substances using devices such as germanium semiconductor detectors used in food inspections. It was necessary to use the measurement method evaluated in Since this measurement method takes a day or more to measure, it could not be used to evaluate the risk of contaminated water at the site of decontamination work.

JP-A-11-242097

  The present invention has been made in view of the above-mentioned problems, and its purpose is to suppress the generation amount of contaminated water in a cleaning apparatus and a cleaning method in which cleaning water is sprayed on and washed away from contaminants attached to structures and the like. Another object of the present invention is to provide a cleaning apparatus and a cleaning method that can prevent re-scattering of contaminants and improve the safety of workers performing cleaning operations.

  In order to achieve the above object, a cleaning device according to the present invention is a cleaning device that injects cleaning water onto a contaminant adhered to a structure to wash it away, and the cleaning device purifies the cleaning water. An injection nozzle that injects the cleaning water, a recovery mechanism that recovers the first contaminated water that is injected from the injection nozzle and includes the contaminant, a filter that removes the contaminant from the first contaminated water, and A circulation mechanism that circulates the second contaminated water that has passed through the filter to the upstream side of the filter again, the circulation mechanism having a reverse osmosis membrane, and the cleaning device from the circulation mechanism to the reverse osmosis It has a resupply circuit for supplying pure water to the washing water purification mechanism through a membrane.

  With this configuration, it is possible to prevent a problem that a large amount of contaminated water is generated. This is because pure water obtained by purifying contaminated water (cleaning water containing contaminants) through a filter and reverse osmosis membrane can be supplied to the cleaning water purification mechanism and used again as cleaning water. It is. Further, the cleaning performance of the cleaning device can be improved, and the pressure of the cleaning water sprayed from the spray nozzle can be suppressed. This is because pure water having a high cleaning ability is supplied to the cleaning water purification mechanism through the resupply circuit. Furthermore, by using the reverse osmosis membrane, almost all of the contaminants (for example, radioactive substances) in the contaminated water can be recovered.

  In the cleaning apparatus, the contaminant includes a radioactive substance. With this configuration, the radioactive material can be prevented from being scattered again.

  In the above-described cleaning apparatus, the cleaning water purification mechanism includes a microvalve generating mechanism for adding a microvalve to the cleaning water. With this configuration, scattering of contaminants can be prevented. This is because the contaminants can be efficiently washed away even if the water pressure of the washing water jetted from the jet nozzle is suppressed to 0.98 MPa or less by installing the microvalve generating mechanism. Further, the adoption of the circulation mechanism can improve the collection efficiency of contaminants by the filter.

  In the above-described cleaning apparatus, the filter is a non-woven fabric supporting at least one of zeolite or Prussian blue. This configuration can improve worker safety. This is because, for example, a radioactive substance such as cesium is adsorbed by a filter and separated from water that absorbs radiation, and the radiation dose can be easily measured by a dosimeter such as a Geiger counter. In addition, the operator can easily know the degree of danger in the working environment where the cleaning operation is performed by measuring the radiation dose in the vicinity of the filter.

Here, Prussian blue is called iron (III) hexanecyanoferrate (II), ferric ferrocyanide (III), or ferric ferric iron, and the composition formula is Fe (III) ₄ [Fe (II) (CN) ₆ ] is a substance that becomes ₃ .

  In the cleaning apparatus, the cleaning apparatus has an addition mechanism for adding at least one of edetic acid, citric acid, or phytic acid to the cleaning water. With this configuration, since the cleaning performance of the cleaning water is improved, the pressure of the cleaning water sprayed from the spray nozzle can be suppressed, and re-scattering of contaminants including radioactive substances can be prevented. Further, since the washing water becomes weakly acidic, it is possible to improve the adsorption performance of contaminants such as radioactive substances in the filter carrying Prussian blue. This is because the action of adsorbing Prussian blue cesium is particularly strong in the acidic region.

In order to achieve the above object, a cleaning method according to the present invention is a cleaning device that sprays cleaning water on a contaminant containing a radioactive substance adhering to a structure, and the cleaning device purifies the cleaning water. A cleaning water purification mechanism, an injection nozzle for injecting the cleaning water, a recovery mechanism for recovering the first contaminated water injected from the injection nozzle and containing the contaminant, and removing the contaminant from the first contaminated water A circulation mechanism that circulates the filter and the second contaminated water that has passed through the filter to the upstream side of the filter again, the circulation mechanism includes a reverse osmosis membrane, and the cleaning device includes the circulation mechanism. A cleaning method using a cleaning device having a resupply circuit for supplying pure water to the cleaning water purification mechanism from the reverse osmosis membrane through the reverse osmosis membrane, the cleaning step for spraying the cleaning water onto the contaminant, water A recovery step of recovering, a first purification step of removing the contaminant from the first contaminated water with the filter, a second purification step of removing the contaminant from the second contaminated water with a reverse osmosis membrane, and the second A resupply step for supplying pure water generated in the purification step to the washing water purification mechanism via the resupply circuit; and a circulation step for circulating the concentrated water generated in the second purification step to the filter. Features. With this configuration, the same effects as described above can be obtained.

  According to the cleaning device and the cleaning method of the present invention, the cleaning device and the cleaning that can suppress the generation amount of contaminated water, prevent re-scattering of contaminants, and improve the safety of workers performing the cleaning operation. A method can be provided.

It is the schematic which showed the structure of the washing | cleaning apparatus of embodiment which concerns on this invention.

  Hereinafter, a cleaning apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a cleaning apparatus 1 according to an embodiment of the present invention. The cleaning device 1 includes a cleaning water purification mechanism 2 for purifying cleaning water (Wash Water) Ww, an injection nozzle 3 for injecting the cleaning water Ww, and a first contaminated water (Tainted) that is injected from the injection nozzle 3 and contains contaminants. Water) A recovery mechanism 4 that recovers Wt1, a filter 5 that removes contaminants from the first contaminated water Wt1, and a circulation mechanism 6 that circulates the second contaminated water (Wt2) that has passed through the filter 5 to the upstream side of the filter 5 again. have.

  Further, the circulation mechanism 6 has a reverse osmosis membrane 7 in a part thereof. The reverse osmosis membrane 7 has a function of purifying the supplied second contaminated water Wt2 to generate pure water (Pure Water) Wp, and discharging the remaining portion as concentrated water (Concentrated Water) Wc. . The pure water Wp is supplied from the reverse osmosis membrane 7 to the cleaning water purification mechanism 2 via the resupply circuit 8.

  Further, the cleaning water purification mechanism 2 has a microvalve generating mechanism 10 that adds a microvalve to the cleaning water Ww, and an addition mechanism 11 that supplies an additive to the cleaning water Ww. This additive improves the washing ability of washing water, and is preferably composed of edetic acid, citric acid, phytic acid or the like.

  In addition, the cleaning device 1 includes a pressurizing pump 12 that pressurizes the cleaning water Ww supplied to the spray nozzle 3. The pressure of the washing water Ww pressurized by the pressure pump 12 is 0.98 MPa or less, which is about the same as a shower used in a general household bathroom. Reference numeral 20 denotes a structure such as a house.

  Next, a method (decontamination method) of washing away radioactive materials attached to the wall surface of the structure 20 and the roof using the cleaning device 1 will be described. First, the cleaning water Ww in the cleaning water purification mechanism 2 is added with a microvalve by the microvalve generating mechanism 10 and sent to the injection nozzle 3 by the pressure pump 12. An operator injects cleaning water Ww onto a radioactive substance (contaminant) attached to the outer wall surface of the structure 20 (cleaning step). This washing water Ww becomes the first contaminated water Wt1 containing a radioactive substance, and is collected by the collection mechanism 4 (collection step).

  This collection mechanism 4 can be configured by a tray or the like installed in a place where the first contaminated water Wt1 flows and concentrates, such as a gutter or a gutter in a house. Further, a pump 15 may be added to the recovery mechanism 4 to form a suction type recovery mechanism. With this configuration, the recovery efficiency of the first contaminated water Wt1 can be improved.

  The first contaminated water Wt1 recovered by the recovery mechanism 4 is sent to the filter 5 by a pump 15 or gravity, and the radioactive substance is adsorbed and recovered by the filter 5 (first purification step). The second contaminated water Wt2 from which many radioactive substances have been removed is sent to the circulation mechanism 6 having the reverse osmosis membrane 7.

  The second contaminated water Wt2 is separated from the pure water Wp and the concentrated water Wc by removing almost all radioactive substances and other contaminants by the reverse osmosis membrane 7 (second purification step). The generated pure water Wp is supplied to the cleaning water purification mechanism 2 via the resupply circuit 8 (resupply step). The remaining concentrated water Wc is again supplied to the upstream side of the filter 5 through the circulation mechanism 6 (circulation step).

  The cleaning apparatus 1 can perform the decontamination work by collecting the radioactive material attached to the building 20 or the like with limited water by repeating the above steps. In addition, after completion of the decontamination work, the filter 5 in which radioactive substances are concentrated is collected and stored in a storage room surrounded by a radioactive shielding member or the like.

  With the above configuration, the following operational effects can be obtained. First, the configuration in which the reverse osmosis membrane 7 is installed in the circulation circuit 6 can prevent the generation of a large amount of contaminated water. This is because most of the cleaning water Ww sprayed from the spray nozzle 3 can be used again as cleaning water as pure water Wp. Therefore, the time cost and the monetary cost required for transporting and processing the contaminated water can be greatly suppressed. Moreover, since the pure water Wp produced | generated with the reverse osmosis membrane 7 can be utilized as the washing water Ww, the washing | cleaning performance of the washing water Ww can further be improved.

  Secondly, the configuration in which the microbubble generation mechanism 10 is installed in the cleaning water purification mechanism 2 can prevent re-scattering of contaminants such as radioactive substances. This is because even if the water pressure of the cleaning water Ww sprayed from the spray nozzle 3 is low (0.98 MPa or less), contaminants attached to the structure 20 and the like can be washed away. Moreover, since the water pressure of the cleaning water Ww to be sprayed is low, it is possible to clean the roof of the house by installing the spray nozzle 3 at the end of the rod-shaped object as shown in FIG. Since this operation was not possible with conventional high-pressure cleaning, the operator had to climb on the roof or the like to perform the cleaning operation.

  Third, the safety of the operator can be improved. In particular, when the pollutant contains a radioactive substance, it is difficult for an operator to recognize the amount of the radioactive substance contained in the contaminated water Wt1 and Wt2 and the danger thereof, but the radioactive substance radiation collected by the filter 5 is present. This is because the amount can be easily measured with a Geiger counter or the like.

  In addition, when a pollutant contains a radioactive substance, it is desirable to carry | support the filter 5 comprised with the nonwoven fabric by carrying Prussian blue, a zeolite, or a silica. It is because the adsorption efficiency of the radioactive substance in the filter 5 can be improved. In particular, Prussian blue is a pigment for dyeing cloth, and can be easily supported on a nonwoven fabric. Moreover, since the filter of the nonwoven fabric which carry | supported Prussian blue will be only a cesium, carbon, and a pigment component (Prussian blue) if it incinerates after use, a volume can be reduced easily. Furthermore, it is good also as a structure which arrange | positions the filter 5 in a vinyl chloride pipe | tube. This is because the vinyl chloride tube can shield radiation by this configuration.

  The addition mechanism 11 is preferably controlled so as to measure the amount of pure water Wp supplied from the resupply circuit 8 and to determine the supply amount of the additive according to the amount of pure water Wp. This is because the cleaning ability of the cleaning water Ww can be maximized.

  Furthermore, the additive is not limited to the aforementioned edetic acid, citric acid, phytic acid, or the like, and may be any substance that makes the wash water Ww weakly acidic and has an action of taking in metal ions (chelating action). This is because contaminants such as radioactive substances adhering to the structure 20 and the like can be taken in and easily washed away by chelating action. In addition, it is because the radioactive substance taken in becomes easy to be adsorbed by the Prussian blue of the filter 5 by the action of making the washing water Ww weakly acidic. In addition, a hydrocarbon-based compound that is typified by limonene and dissolves fats and oils and fine petroleum-based materials may be added as an additive. Specific examples include α-pinene, β-pinene, R-terpinene, geraniol acetate, bornyl acetate, and lunarol acetate. Alcohols such as geraniol and linalool also produce similar effects. In addition, you may add Pricyan blue to the additive. This is because cesium can be adsorbed from the time of cleaning, and the cleaning effect of the cleaning device 1 can be enhanced.

  In addition, the cleaning apparatus 1 can be mounted on a loading platform such as a truck and moved to an arbitrary outdoor location to efficiently perform decontamination work. In particular, since the cleaning apparatus 1 can circulate and use a certain amount of water without generating a large amount of contaminated water Wt1 and Wt2, continuous operation for a long time can be easily performed.

  In addition, the cleaning apparatus 1 can also clean scattered contaminants such as the ground surface. Specifically, a non-woven filter is first laid on the ground surface, and cleaning water is sprayed from above. The recovery mechanism is of a suction type, and is configured to contact the surface of a filter laid on the ground surface to suck and collect contaminated water. Here, contaminants on the ground surface are adsorbed on the filter together with the washing water by capillary action. With this configuration, contaminants such as the ground surface can be scattered and collected without flowing out into the side groove or the like. At this time, the washing water sprayed on the filter may be heated water vapor. With this configuration, it becomes easy to peel off contaminants from the ground surface, and the cleaning effect can be improved.

  As described above, according to the cleaning device 1 and the cleaning method of the present invention, it is possible to efficiently perform the decontamination work for removing the radioactive material attached to the building 20 or the like. Note that the pollutant to be cleaned by the present invention is not limited to a radioactive substance. The cleaning apparatus 1 can perform cleaning by appropriately determining the performance and the like of the filter 5 according to the target pollutant, even for pollutants other than radioactive substances.

DESCRIPTION OF SYMBOLS 1 Washing apparatus 2 Washing water refinement | purification mechanism 3 Injection nozzle 4 Collection | recovery mechanism 5 Filter 6 Circulation mechanism 7 Reverse osmosis membrane 8 Resupply circuit 10 Micro valve generation mechanism 11 Addition mechanism 20 Structure Ww Washing water Wt1 1st contaminated water Wt2 2nd pollution Water Wp Pure water Wc Concentrated water

Claims (6)

In a cleaning device that sprays cleaning water on contaminants adhering to structures,
The cleaning device is a cleaning water purification mechanism for purifying the cleaning water, an injection nozzle for injecting the cleaning water, a recovery mechanism for recovering the first contaminated water that is injected from the injection nozzle and contains the contaminant, A filter that removes the contaminant from the first contaminated water, and a circulation mechanism that circulates the second contaminated water that has passed through the filter to the upstream side of the filter again,
The circulation mechanism has a reverse osmosis membrane;
The cleaning apparatus includes a resupply circuit that supplies pure water from the circulation mechanism to the cleaning water purification mechanism through the reverse osmosis membrane.   The cleaning apparatus according to claim 1, wherein the contaminant includes a radioactive substance.   The cleaning apparatus according to claim 1, wherein the cleaning water purification mechanism includes a microvalve generating mechanism that adds a microvalve to the cleaning water.   The cleaning apparatus according to claim 2 or 3, wherein the filter is a nonwoven fabric carrying at least one of zeolite or Prussian blue.   The said washing | cleaning apparatus has an addition mechanism which adds at least 1 of edetic acid, a citric acid, or a phytic acid to the said washing water, The any one of Claim 2 thru | or 4 characterized by the above-mentioned. Cleaning device. This is a cleaning device that sprays cleaning water on the pollutants that contain radioactive substances attached to the structure.
The cleaning device is a cleaning water purification mechanism for purifying the cleaning water, an injection nozzle for injecting the cleaning water, a recovery mechanism for recovering the first contaminated water that is injected from the injection nozzle and contains the contaminant, A filter that removes the contaminants from the first contaminated water, and a circulation mechanism that circulates the second contaminated water that has passed through the filter to the upstream side of the filter, and the circulation mechanism includes a reverse osmosis membrane. The cleaning apparatus is a cleaning method by a cleaning apparatus having a resupply circuit for supplying pure water from the circulation mechanism to the cleaning water purification mechanism through the reverse osmosis membrane,
A cleaning step of spraying cleaning water onto the contaminant;
A recovery step of recovering the first contaminated water;
A first purification step of removing the contaminant from the first contaminated water with the filter;
A second purification step of removing the contaminant from the second contaminated water with a reverse osmosis membrane;
A resupply step of supplying pure water generated in the second purification step to the washing water purification mechanism via the resupply circuit;
A cleaning method comprising a circulation step of circulating the concentrated water generated in the second purification step to the filter.

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