JP5897267B2 - Water purifier - Google Patents

Description

  The present invention relates to a water purifier.

  Conventionally, water purifiers have been used for the purpose of making tap water used as drinking water safer. For example, Patent Document 1 describes a water purifier having a membrane filter that collects unpurified matter from reversely osmotic pressure from taken tap water and the like, and another filter provided on the downstream side of the membrane filter. Yes.

JP-A-11-57706

By the way, when a radioactive substance such as iodine 131 is mixed in tap water, it is considered difficult to remove the radioactive substance even if a conventional filter is used. Therefore, it is generally pointed out that the use of tap water mixed with radioactive substances may cause harm to the human body.
An object of the present invention is to prevent the use of tap water mixed with a radioactive substance to the extent that it has a harmful effect on the human body before the tap water is purified by the water purifier.

Thus, the inventions according to the following [1] to [6] are provided.
[1] The invention according to claim 1 includes: a radiation detection unit that detects radiation from tap water; a purification unit that is provided downstream of the radiation detection unit and purifies the tap water; and the radiation detection unit. A flow path blocking means provided on the downstream side and upstream of the purification means, and when the radiation detection means detects radiation from the tap water, blocks the flow path to the tap water to the purification means; It is a water purifier characterized by having.
[2] The water purifying apparatus according to claim 1, further comprising discharge means for discharging the tap water when the radiation detecting means detects radiation from the tap water. It is a vessel.
[3] The invention according to claim 3 has display means for displaying detection of the radiation when the radiation detection means detects radiation from the tap water. It is a water purifier.
[4] The water purifier according to any one of claims 1 to 3, wherein the purification means includes a porous silicon carbide structural material carrying a photocatalyst. is there.
[5] In the invention according to claim 5, the purification means further includes an ultraviolet light guide disposed so that ultraviolet energy can be irradiated to the photocatalyst carried inside the porous silicon carbide structural material. It is a water purifier of Claim 4 characterized by the above-mentioned.
[6] The invention according to claim 6, further wherein the purifying means includes, in claim 5, characterized in that it comprises a light emitting diode (LED) which ultraviolet energy is introducible disposed in the ultraviolet light guide It is a water purifier of description.

  ADVANTAGE OF THE INVENTION According to this invention, before performing the purification process of the tap water by a water purifier, the use of the tap water mixed with the radioactive substance to such an extent that it has a harmful effect on the human body can be prevented.

It is a flow sheet explaining an example of a water purifier to which this embodiment is applied. It is a flowchart explaining the control step in a control part. It is a figure explaining an example of the purification filter which comprises the purification tank of the water purifier to which this Embodiment is applied.

  Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the invention. The drawings used are for explaining the present embodiment and do not represent the actual size.

Drawing 1 is a flow sheet explaining an example of a water purifier to which this embodiment is applied.
As shown in FIG. 1, the water purifier A is a radiation detector that detects radiation from radioactive substances contained in tap water from upstream to downstream of tap water (purified water) flowing out from the tap 1 of the tap. 2 (radiation detection means), an electromagnetic valve 3 that opens and closes based on a radiation detection signal, and a septic tank 5 (purification means) that purifies tap water are connected by a pipe.
When the radiation detector 2 detects the radiation, the electromagnetic valve 3 shuts off the tap water flow path (flow path blocking means), and the drain valve 32 discharges the tap water from which the radiation has been detected (discharge). Means) and a three-way valve. Moreover, when the radiation detector 2 detects a radiation, it has the display apparatus 4 (display means) which displays that. Furthermore, the control part 6 which controls opening / closing of the solenoid valve 3 and the action | operation of the display apparatus 4 when the radiation detector 2 detects a radiation is provided.

The radiation detector 2 is not particularly limited, and examples thereof include a Geiger-Muller (GM) counter, a scintillation detector, a proportional counter, and an ionization chamber.
The solenoid valve 3 is a three-way valve that combines both the shut-off of the tap water flow path and the drainage. Normally, it is opened to secure a flow path to the tap water purification tank 5, but when radiation is detected by the radiation detector 2, the flow path to the tap water purification tank 5 is blocked by the shut-off valve 31. Then, the drain valve 32 is opened to discharge the tap water containing the radioactive material.
The display device 4 is not particularly limited, and examples thereof include display using light such as a display lamp; display using sound such as a buzzer; display using color such as coloring.
The purification tank 5 is provided with a purification filter for purifying the tap water. The purification filter is not particularly limited, and examples thereof include a reverse osmosis membrane, activated carbon, silicon carbide, silicon nitride, silicon and the like.
In the present embodiment, the opening / closing of the shutoff valve 31 and the drain valve 32 and the operation of the display device 4 are controlled by the control unit 6 based on the radiation detection signal from the radiation detector 2.

FIG. 2 is a flowchart for explaining control steps in the control unit 6.
First, the tap 1 of the water supply is opened (step 101), and the tap water as the water to be purified passes through the portion of the pipe 1a where the radiation detector 2 is provided (step 102) and is harmful to the human body due to the detection of radiation. It is determined whether or not there is a radioactive substance that has a significant influence (step 103).
As a result of the detection of radiation by the radiation detector 2, when it is determined that there is no radioactive substance that does not detect radiation and has a harmful effect on the human body (YES), the shut-off valve 31 of the electromagnetic valve 3 is opened ( When the drain valve 32 is closed (step 104), the tap water is sent to the septic tank 5 via the pipe 2a → the electromagnetic valve 3 → the pipe 3b, and a purification process is performed (step 105). The tap water after the purification treatment is used as drinking water or the like through the pipe 5a.

  On the other hand, if it is determined that there is a radioactive substance that has a harmful effect on the human body as a result of detection of radiation by the radiation detector 2 (NO), the shutoff valve 31 of the electromagnetic valve 3 is closed and the flow path of tap water Is blocked (step 106). Next, after the drain valve 32 is opened (step 107) and radiation detection is simultaneously displayed on the display device 4 (step 108), the tap water passes through the pipe 2a → the electromagnetic valve 3 (drain valve 32) → the pipe 3a. And drained (step 109). Thereby, before performing the purification process of the tap water by the water purifier A, it is possible to prevent the use of the tap water mixed with radioactive substances to the extent that it has a harmful effect on the human body.

FIG. 3 is a diagram for explaining an example of the purification filter 100 constituting the purification tank 5 (see FIG. 1) of the water purifier A to which the present embodiment is applied.
As shown in FIG. 3, the purification filter 100 includes a porous silicon carbide structural material 10 that carries a photocatalyst 30 and an ultraviolet light guide 20. The ultraviolet light guide 20 is disposed substantially parallel to the direction (B) of the water to be purified.
The porous silicon carbide structural material 10 has silicon carbide (SiC) as a skeleton, and has a three-dimensional porous structure through which a fluid to be purified can pass when used as a filter. The skeleton of silicon carbide (SiC) has an average cross-linking thickness of 1 mm or less and a porosity of 85% by volume or more.

  The ultraviolet light guide 20 is disposed inside the porous silicon carbide structural material 10 in order to irradiate the photocatalyst 30 carried inside the porous silicon carbide structural material 10 with ultraviolet energy having a wavelength of 200 nm to 400 nm. ing. Ultraviolet energy generated by the light emitting diode (LED) 200 is introduced into the ultraviolet light guide 20 using a power source (not shown) provided outside the purification filter 100. In the present embodiment, NS375L-5RLL (emission wavelength: 375 nm to 380 nm, emission output: 8.4 mW to 14.0 mW) manufactured by Nitride Semiconductor Co., Ltd. may be used as the light emitting diode (LED) 200.

  In the present embodiment, the ultraviolet light guide 20 is preferably formed from an ultraviolet light transmissive material having a light transmittance of ultraviolet light having a wavelength of 300 nm of 70% or more. Usually, it is known that the photocatalyst 30 exhibits a catalytic action when irradiated with ultraviolet energy having a wavelength of 400 nm or less. For this reason, the photocatalyst 30 carried inside the porous silicon carbide structural material 10 is efficiently activated by forming the ultraviolet light guide 20 using a material having a high ultraviolet light transmittance. Examples of the ultraviolet transmissive material include an ultraviolet transmissive acrylic resin. Examples of such acrylic resins include commercially available products such as methacrylic resin Paragrass (registered trademark) manufactured by Kuraray Co., Ltd., Sumipex 010 manufactured by Sumitomo Chemical Co., Ltd.

The photocatalyst 30 may be a metal oxide capable of performing a photocatalytic reaction by oxidative decomposition of harmful organic substances contained in a fluid such as sewage to be purified, and is not particularly limited. For example, titanium dioxide (particularly anatase-type titanium dioxide), rutile-type titanium dioxide, brookite-type titanium dioxide and the like can be mentioned. Furthermore, zinc oxide, tin oxide, lead oxide, ferric oxide and the like may be included. In the present embodiment, the photocatalyst 30 preferably contains 50 mass% or more of anatase type titanium dioxide. In addition, you may use these compounds in mixture of multiple types suitably. The photocatalyst 30 can be used in various forms such as powder, lump, granule, flat plate, and fiber. In the present embodiment, powdered titanium dioxide having an average particle diameter of 1 nm to 100 nm is used.
The amount of the photocatalyst 30 carried inside the porous silicon carbide structural material 10 is not particularly limited. In this Embodiment, it prepares in 0.01 to 99.9% of range.

The porous silicon carbide structural material 10 is manufactured by the following manufacturing method, for example.
First, a tangible skeleton of a sponge-like porous structure is impregnated with a slurry (Si slurry) in which a resin as a carbon source and silicon powder are mixed, and then dried at about 70 ° C. for about 12 hours. At this time, it is preferable to squeeze the slurry liquid to such an extent that the slurry liquid does not block the continuous pores.
Examples of the sponge-like porous structure include foamed polyurethane. Examples of the resin for the Si slurry include a phenol resin, a furan resin, and an organometallic polymer. If necessary, additives such as carbon powder, graphite powder, carbon black, aggregate, and antioxidant are added. The silicon powder is particularly preferably a fine powder having an average particle size of about 1 μm to 10 μm. Examples of the dispersion medium for the Si slurry include methyl alcohol and ethyl alcohol.

Next, the sponge-like porous structure impregnated in the slurry liquid and dried is carbonized at a temperature of about 900 ° C. to 1350 ° C. in an inert atmosphere such as vacuum or argon. As a result, a carbonized porous structure is obtained. This porous structure is a carbonized composite in which a carbon portion obtained by carbonization of a phenol resin and silicon powder are mixed. Subsequently, the carbonized porous structure is fired at a temperature of 1350 ° C. or higher in an inert atmosphere such as vacuum or argon, and carbon and silicon are reacted so that silicon carbide is a porous structure. A porous structure sintered body formed on the tangible skeleton portion is obtained. Furthermore, this porous structure sintered body is obtained by heating at a temperature of about 1300 ° C. to 1800 ° C. in a vacuum or an inert atmosphere to obtain a porous silicon carbide structural material 10 having a tangible skeleton melt-impregnated with silicon. .
In the present embodiment, the mixing ratio of silicon (Si) of silicon powder and carbon (C) such as phenol resin used in the production of porous silicon carbide structural material 10 is silicon (Si) and carbon ( It is desirable to select the atomic ratio with C) so that Si / C = 0.05-4.

In the present embodiment, the photocatalyst 30 is normally carried on the porous silicon carbide structural material 10 by the following procedure. That is, the porous silicon carbide structural material 10 prepared by the manufacturing method described above is immersed in a slurry (TiO ₂ slurry) containing a photocatalyst 30 such as titanium dioxide (TiO ₂ ), dried, and then 100 ° C. in the atmosphere. Baking at a temperature of about ~ 800 ° C. In addition, water is used as a dispersion medium for the TiO ₂ slurry.
In the present embodiment, for example, titanium dioxide (TiO ₂ ) or the like is added to the TiO ₂ slurry in an aqueous solution of polyvinyl alcohol, and adjusted to a predetermined viscosity. Polyvinyl alcohol is also useful as a binder for fixing TiO ₂ to the surface of the porous silicon carbide structural material 10.
The concentration of titanium dioxide (TiO ₂ ) in the TiO ₂ slurry is not particularly limited, but in the present embodiment, when supported on the porous silicon carbide structural material 10, the moles of titanium (Ti) and carbon (C). The ratio (Ti / C) is adjusted to be in the range of 0.1-2.

The water purifier A to which the present embodiment is applied has a radioactive substance that has a harmful effect on the human body by measuring radiation in advance before the tap water is purified by the septic tank 5. If it is determined that the tap water is discharged, it is prevented from being used as drinking water.
Moreover, the detection of the radiation by the water purifier A to which this Embodiment is applied is not limited to the tap water which flows out from a tap. For example, detection can be performed by injecting water used for washing vegetables or the like into the water purifier A.

Furthermore, although not illustrated, as a result of detection of radiation by the radiation detector 2, when it is determined that there is a radioactive substance that has a harmful effect on the human body, as an operation controlled by the control unit 6 of the water purifier A, For example, the following matters are mentioned.
(1) Close the tap water supply line supplied to the home. Thereby, use of the tap water contaminated with the radioactive substance from the other faucets etc. which are not connected with the water purifier A can be avoided.
(2) Transmit danger information to a mobile phone terminal, the Internet or a communication device. Thereby, automatic notification to related organizations is performed, and it becomes possible to share danger information and to collect information.
(3) Stop reuse of water purifier A. Thereby, the safety confirmation measure of the water purifier A can be performed.

DESCRIPTION OF SYMBOLS 1 ... Faucet, 2 ... Radiation detector, 3 ... Solenoid valve, 4 ... Display apparatus, 5 ... Septic tank, 6 ... Control part, 10 ... Porous silicon carbide structural material, 20 ... Ultraviolet light guide, 30 ... Photocatalyst, 31 ... Shut-off valve, 32 ... Drain valve, 100 ... Purification filter, 200 ... Light emitting diode (LED)

Claims (6)

Radiation detection means for detecting radiation from tap water;
A purification means provided on the downstream side of the radiation detection means, for purifying the tap water;
Provided downstream of the radiation detection means and upstream of the purification means, and when the radiation detection means detects radiation from the tap water, the flow path to the purification water is cut off. A channel blocking means;
The water purifier characterized by having.   The water purifier according to claim 1, further comprising a discharge unit that discharges the tap water when the radiation detection unit detects radiation from the tap water.   The water purifier according to claim 1 or 2, further comprising display means for displaying the detection of the radiation when the radiation detection means detects radiation from the tap water.   The water purifier according to any one of claims 1 to 3, wherein the purification means includes a porous silicon carbide structural material carrying a photocatalyst.   Furthermore, the said purification | cleaning means is equipped with the ultraviolet-ray light guide arrange | positioned so that an ultraviolet energy can be irradiated to the said photocatalyst carried inside the said porous silicon carbide structural material. Water purifier. The water purifier according to claim 5 , wherein the purification means further comprises a light emitting diode (LED) disposed in the ultraviolet light guide so that ultraviolet energy can be introduced.

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