JP3751147B2 - Purification agent and water purification apparatus using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a purifier and a water purifier used for water purification treatment of drinking water, aquarium water for breeding fish, bath water, washing water, etc., and a purifier and a water purifier for the purpose of removing dissolved substances in water and maintaining water quality It is about.
[0002]
[Prior art]
Water may have dirt, sand, and other odors and tastes due to chlor and fungi, and needs to be purified before it can be used for domestic water. In addition, fish tanks for appreciation and aquaculture tend to cause turbidity of water, generation of algae, and high concentration of ammonia in water due to feeds given to domestic fish and aquatic plants and excretion from domestic fish. Therefore, it is necessary to purify the aquarium water in order to prevent adverse effects on the domestic fish.
[0003]
Conventionally, various methods such as filtration, adsorption / removal of harmful substances in water, ozone treatment, biological treatment, oxidative decomposition treatment using a photocatalyst, and regular water exchange have been used as water purification means. Replacing the aquarium water is a direct purification of water, but it is necessary to perform troublesome replacement work at a frequency of once every two weeks. The filtration filter must be replaced every time it is clogged, and it cannot cope with the removal of substances dissolved in water.
[0004]
There are two types of adsorption removal, one using physical adsorption using activated carbon and the other using chemical adsorption using ion-exchange resin or zeolite. If saturates, it must be replaced. In particular, activated carbon has a high ability to adsorb and remove organic matter and alkyds, but has a problem that the ability to adsorb inorganic substances such as ammonia is low, and zeolite has a problem that the adsorption ability varies depending on the production method, surface area, and crystal phase. . Furthermore, although it is possible to remove substances dissolved in water, it cannot be a direct means for maintaining the transparency of water and suppressing the generation of algae in the aquarium.
[0005]
Although the ozone treatment is used for sewage treatment and is a method having water purification and sterilization ability, it requires treatment of residual ozone and has a problem that the apparatus becomes large. Biological treatment uses microorganisms having nitrification ability and has high nitrification ability of ammonia, but there is a problem that several tens of days are required for culturing and starting up microorganisms. Moreover, it cannot be a means for maintaining the transparency of water or suppressing the generation of algae in the water tank.
[0006]
As the oxidative decomposition treatment using a photocatalyst, for example, in JP-A-8-228636, a purification agent is obtained by carrying a photocatalyst on an adsorbent composed of Si and O-containing inorganic substances such as zeolite. According to this cleaning agent, ammonia in water can be decomposed and removed.
[0007]
In addition, in the water purifier disclosed in Japanese Patent Application No. 8-339267, a water purifier is disclosed in which a purifying agent carrying a photocatalyst on an adsorbent mainly composed of a photocatalyst or silica and a filtration filter are used in combination. . This water purifier is not only capable of decomposing ammonia, but also capable of collecting large-size dust and decomposing organic matter, and can be a means for maintaining the transparency of water and suppressing the generation of algae in the water tank.
[0008]
[Problems to be solved by the invention]
However, the above Japanese Patent Application Laid-Open No. 8-228636 and Japanese Patent Application No. 8-339267 do not mention maintenance of water quality or decomposition of chalk. In addition, ammonia in water is decomposed into nitrous acid and nitric acid by microorganisms having a nitrifying action, but when the concentration of this chemical increases, the pH of water shifts to the acidic side and affects the survival of domestic fish. There is no consideration of means for this acidification.
[0009]
Moreover, in the water purifier of Japanese Patent Application No. 8-339267, the supplied water falls on the upper surface of the filtration filter so that the particles of the photocatalyst or the purifier on the upper surface of the filtration filter are not scattered by the momentum of the water supply. It is fixed. Therefore, a process for fixing the particles on the upper surface of the filtration filter is required to produce this water purifier.
[0010]
In view of the above problems, it is an object of the present invention to provide a purifying agent capable of decomposing chlorine and maintaining water quality in addition to more powerful decomposition of ammonia. Another object of the present invention is to provide a water purifier capable of adjusting the pH of water and having a simple configuration.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the purifier used in the water purifier of the present application is composed of an adsorbent mainly composed of SiO ₂ and Al ₂ O ₃ and a photocatalyst supported on the adsorbent. In this cleaning agent, ammonia is adsorbed on the adsorbent, and the ammonia is decomposed by photocatalysis. In addition, the photocatalyst also breaks down water and organic matter.
[0012]
In the purification agent having the above-described configuration , the adsorbent is a solid acid, and the chemical configuration is represented by H _n Al _n Si _96-n O ₁₉₂ . There are various porous materials such as activated carbon, alumina balls, artificial zeolite, and natural minerals as adsorbents. Each has adsorbing characteristics, and it is necessary to select an adsorbent according to the substance in water to be adsorbed and removed. As the adsorbent used in the present invention, it is necessary to select an adsorbent excellent in ammonia adsorption ability. Considering that ammonia exhibits alkalinity in water, the adsorbent used is a solid acid containing hydrogen ions as a component. Is preferred.
[0013]
Further, in the purifying agent of the above-described structure, the molar ratio of the absorbent comprising SiO ₂ and Al ₂ O ₃ Metropolitan the _{(SiO 2 / Al 2 O 3} ) may be 10 or more. This adsorbent has a high solid acid strength and easily adsorbs ammonia.
[0014]
Further, in the purifying agent of the above-described structure, the photocatalytic titanium dioxide, or when the titanium dioxide was deposited a noble metal on the surface. As for the photocatalyst, there are various metal oxides having different energy gaps and oxidation-reduction potentials, but titanium dioxide is preferable in consideration of photoactivity and oxidizing power. Titanium dioxide having a noble metal deposited on the surface is preferable because the decomposition ability is further improved.
[0015]
The water purifier of the present application is supplied from a water supply port for supplying water, a filtration filter provided with a photocatalyst or a purification agent on its upper surface, an ultraviolet irradiation means for irradiating ultraviolet light on the upper surface of the filtration filter, and the water supply port. A water flow buffer unit for buffering the momentum of water and allowing water to gently flow into the filter, and a water storage unit for storing water that has passed through the filter, the photocatalyst or the purifying agent being added to the filter. The adsorbent is composed of an adsorbent and a photocatalyst supported on the adsorbent, and the adsorbent is a solid acid mainly composed of SiO ₂ and Al ₂ O ₃ . The chemical composition is represented by H _n Al _n Si _96-n O ₁₉₂ , and the photocatalyst is titanium dioxide or titanium dioxide having a noble metal deposited on the surface.
Further, in the water purifier having the above-described configuration, a drain pipe that maintains a constant water level in the water reservoir is provided upright on the bottom surface of the water reservoir, and the entire filtration filter is immersed in the water in the water reservoir. It is good to do.
Moreover, the water purifier of the said structure WHEREIN: It is good to provide the holding tray with which the hole was formed in the bottom face, and this holding tray hold | maintains the said filtration filter.
Moreover, the water purifier of the said structure WHEREIN: It is good to set it as the structure which the upper end part of the said holding tray is located higher than the water level in the said water storage part.
[0016]
In this water purifier, the water whose momentum has been weakened by the water buffer is sent to the filter, and the dust having a large particle diameter is removed through the filter. At this time, in contact with the purifier or photocatalyst on the upper surface of the filter, the adsorbent adsorbs inorganic substances and organic substances dissolved in water. In addition, the photocatalyst is oxidatively decomposed by irradiation with ultraviolet rays, and inorganic substances and organic substances dissolved in water or adsorbed on the adsorbent are removed. The organic matter collected by the filter is also decomposed by the photocatalyst.
[0017]
In the water purification apparatus having the above-described configuration, a pH adjuster that maintains the pH of water in a neutral region is immersed in water in the water storage section. In the water purifier, the pH of the water to be treated shifts to the acidic side as ammonia is decomposed into nitrous acid and nitric acid. Therefore, the pH is adjusted to the neutral range by immersing the pH adjusting agent in the water of the water storage section.
[0018]
In the water purifier having the above-described configuration , the pH adjuster is coral stone, an alkali metal compound, or an alkaline earth metal compound. The pH is maintained in a neutral range by the mineral eluted from the pH adjuster.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described. The purifying agent according to the present invention is one in which a photocatalyst is supported on an adsorbent. As the adsorbent, a solid acid obtained from SiO ₂ and Al ₂ O ₃ and containing a hydrogen ion such that its chemical composition is represented by H _n Al _n Si _96-n O ₁₉₂ is used. This makes it suitable for adsorbing ammonia showing alkalinity in water. In addition, if the molar ratio of SiO ₂ to Al ₂ O ₃ (SiO ₂ / Al ₂ O ₃ ) is 10/1 or more, the solid acid strength is increased and it is preferable for adsorption of ammonia.
[0020]
As the photocatalyst, titanium dioxide or titanium dioxide having a surface deposited with a noble metal is used. Titanium dioxide has higher oxidative decomposition ability than other photocatalysts in terms of photoactivity and oxidizing power. Further, when noble metal is deposited on the surface of titanium dioxide, the decomposition ability is further improved.
[0021]
In order to support the photocatalyst on the adsorbent, for example, a sol-gel method may be used. First, an adsorbent molded in a granular form in a titania sol is dipped and pulled up, dried and dried with hot air to gel the surface titania sol. Then, if it bakes at the temperature of 150 degreeC or more, the purification agent of this invention will be obtained. The method for supporting the photocatalyst on the adsorbent is not limited to this.
[0022]
About the water purifier which concerns on this invention, the detailed structure is demonstrated in 2nd Example mentioned later.
[0023]
[First embodiment]
In the first embodiment, the ammonia decomposing ability when water is actually purified using the purifying agent according to the present invention is examined. Here, high-silica zeolite manufactured by Nissan Gardler Co., Ltd. having a molar ratio of SiO ₂ to Al ₂ O ₃ (SiO ₂ / Al ₂ O ₃ ) of 92/1 is used as the adsorbent, and a titanium chelating agent (Matsumoto Pharmaceutical) is used as the photocatalyst. TC-200 manufactured by KK) is used. High silica zeolite is immersed in TC-200, stirred well for 5 minutes, and then pulled up. After drying at room temperature for 5 minutes and hot-air drying at 100 ° C. for 1 hour, baking is performed at 500 ° C. for 2 hours to obtain a cleaning agent.
[0024]
FIG. 1 is a schematic side sectional view of a water purifier used in this experiment. A purifier holding tray 3 is provided in the water storage container 4. The holding tray 3 has a mesh bottom, and 12 holes 31 each having a diameter of 6 mm are formed on each side. Further, the purifying agent 2 is contained in the holding tray 3 and is immersed in the water to be treated 10.
[0025]
The water to be treated 10 is agitated by the agitating member 5 and efficiently comes into contact with the purifier 2 through the holes 31 and the mesh portion of the holding tray 3. Further, an ultraviolet lamp 1 (one sterilizing lamp GL-4 (4W) manufactured by NEC Corporation) is provided above the surface of the water to be treated 10 to irradiate the cleaning agent 2 in the holding tray 3. It is like that.
[0026]
To-be-treated water 10 has 25% ammonia water added to 3 L of distilled water to adjust the ammonia concentration to 20 ppm, and the water temperature is 25 ° C. Further, 5 g of the purifying agent 2 was used, and the ammonia concentration was measured while thoroughly stirring the water to be treated 10.
[0027]
FIG. 2 shows the measurement results of ammonia concentration over time in this water purifier. In addition, as a comparative experiment, a measured value when only 5 g of the adsorbent (high silica zeolite) is used is also recorded. At the start of the experiment, no ultraviolet rays were irradiated. When ammonia was adsorbed on the purifying agent (or high silica zeolite) and the ammonia concentration became constant (4 hours from the start of the experiment), ultraviolet irradiation was started and the ammonia concentration was measured for 28 hours from the start of the experiment. According to this figure, it can be seen that ammonia adsorbed on the adsorbent by the photocatalyst has been decomposed, and that the amount of adsorbent adsorbed is not saturated, and ammonia decomposition and removal in water has progressed.
[0028]
[Second Embodiment]
In the second embodiment, turbidity, COD, and pH when water is actually purified using the water purifier according to the present invention are examined. FIG. 3 is a schematic side sectional view of the water purifier used in this experiment. A filter holding tray 6 having a hole 61 formed in the bottom surface is provided in the water purifier main body 8. The holding tray 6 is provided with a filtration filter 11 parallel to the bottom surface, and granular photocatalysts 2 (ST-B11 manufactured by Ishihara Sangyo Co., Ltd.) are scattered on the upper surface of the filtration filter 11.
[0029]
Reference numeral 9 denotes a water buffer, which contains a buffer material 9a. The water to be treated pumped up by the pump is sent from the water supply port 13 to the water buffer 9 and gradually flows into the holding tray 6. Therefore, since the photocatalyst 2 on the filtration filter 11 does not fall off from the filtration filter 11, it is not necessary to fix the photocatalyst 2 to the upper surface of the filtration filter 11.
[0030]
The drain pipe 7 is provided upright on the bottom surface of the water storage container 4, whereby the water level of the treated water 10 in the water purifier main body 8 becomes constant. The filtration filter 11 of the holding tray 6 is entirely immersed in the water to be treated 10, and the upper end of the side surface of the holding tray 6 is configured to be higher than the water level of the water to be treated 10. Thus, since the filtration filter 11 is always immersed in the water to be treated 10 and a water flow is generated on the upper surface of the filtration filter 11, the water efficiently contacts the photocatalyst 2.
[0031]
An ultraviolet lamp 1 (one sterilization lamp GL-10 (10 W) manufactured by NEC Corporation) is provided above the surface of the water to be treated 10 and irradiates the photocatalyst 2 in the holding tray 6. ing. Further, coral stone 12 as a pH adjusting agent is immersed in the vicinity of the drain pipe 7 in the water purifier main body 8, and the water to be treated 10 comes into contact with the coral stone 12 and is drained from the drain outlet.
[0032]
As the pH adjuster, the following can be used in addition to coral stone. That is, an alkali metal compound such as potassium hydroxide is suitable for quickly adjusting the pH. Also, alkaline earth metal compounds such as magnesium carbonate and magnesium lactate are suitable for slowly dissolving in water and adjusting the pH appropriately.
[0033]
The water purification experiment of the tropical fish tank was performed using the said water purifier. Put 30 tropical fish, 10 shrimp, 6 kinds of aquatic plants in the tank, and adjust the water temperature to 25-30 ° C. Further, light irradiation was performed using two fluorescent lamps of 10 W for 10 hours a day, and feed was introduced twice a day. And 40 days after the start of the experiment, the coral stone 12 was put into the water purifier main body 8, and the water quality of the water tank was examined for 100 days.
[0034]
4 (a), (b), and (c) show the measurement results of turbidity, COD, and pH over time in a water tank using this water purifier. In addition, the measured value by a bio-type purified water tank is also recorded as a comparative experiment. According to this, water quality maintenance effects, such as transparency of aquarium water, are recognized by the above-mentioned water purifier. It can also be seen that the pH adjuster adjusts the pH of the water to a neutral range.
[0035]
[Example 3]
In the third embodiment, the ability of decomposing chlorine when water is actually purified by a photocatalyst using the water purifier used in the first embodiment is examined. Here, ST-B11 manufactured by Ishihara Sangyo Co., Ltd. is used as the photocatalyst. In addition, the water to be treated is adjusted to a chlorine concentration of 2 ppm by adding 0.3% chlorine water to 3 L of distilled water, and the water temperature is 25 ° C. The photocatalyst was irradiated with an ultraviolet lamp (one black light FL-4BL (4W) manufactured by NEC) and the residual chlorine concentration in the treated water was measured for 6 hours while thoroughly stirring the treated water.
[0036]
FIG. 5 shows measurement results of residual chlorine concentration with time in this water purifier. In addition, as a comparative experiment, when only ultraviolet rays are irradiated, when the photocatalyst alone is immersed and no light irradiation is performed, measured values are also recorded for the case where the water to be treated is only stirred (blank). According to this figure, it can be confirmed that chlorine is decomposed by the photocatalyst.
[0037]
【The invention's effect】
As described above, S i O ₂ and A l ₂ O ₃ adsorbent composed mainly of the adsorbent purifying agent composed of a supported photocatalyst adsorbs ammonia with an adsorbent, a photocatalyst is the Since the ammonia is oxidatively decomposed, the adsorbent adsorption amount is not saturated. Therefore, the purification agent of the present invention does not have a problem that the adsorption amount of the adsorbent is saturated and no further water purification action can be obtained. Furthermore, since chlorinated organic substances are oxidatively decomposed by a photocatalyst, they are also effective for decalcifying and maintaining water quality.
[0038]
Further, by using a solid acid as the adsorbent, outstanding ammonia adsorption performance among various adsorbents can be obtained, and the ammonia adsorption efficiency can be improved.
[0039]
Also, in the adsorbent, the solid acid strength of the adsorbent can be increased by further increasing the adsorption capacity for ammonia by increasing the molar ratio of SiO ₂ to Al ₂ O ₃ (SiO ₂ / Al ₂ O ₃ ) to 10 or more. Can do.
[0040]
Further, since titanium dioxide as a photocatalyst or titanium dioxide having a noble metal deposited on the surface thereof is supported, the oxidative decomposition ability is further improved.
[0041]
Moreover , the water purifier of this application provided the water buffer part, and to-be-processed water flows into a filtration filter gently. Therefore, it is not necessary to fix the purification agent or the photocatalyst to the filtration filter, and a simple configuration is required. Further, the purification agent or the photocatalyst and the water to be treated are efficiently brought into contact with each other, so that the dissolved substances in the water are easily adsorbed and oxidized and decomposed. Furthermore, since the photocatalyst decomposes inorganic and organic substances adsorbed on the adsorbent and organic substances collected by the filter, the adsorption amount of the adsorbent is not saturated and the filter is not clogged with organic substances, and maintenance-free. Become.
[0042]
Moreover, in the water purifier of the present application , only by immersing the pH adjusting agent without performing any special treatment, the pH shift of the water during the water purification treatment to the acidic side is prevented, and the water is always neutral. Can keep.
[0043]
Moreover, since the water purifier of this application uses the natural substance which elutes a mineral as a pH adjuster, it is safe and harmless to a human body or an animal.
[Brief description of the drawings]
FIG. 1 is a schematic side sectional view of a purification device according to a first embodiment.
FIG. 2 is a graph showing the change over time in the ammonia concentration in water in the first example.
FIG. 3 is a schematic side sectional view of the purification apparatus used in the second embodiment, which is an embodiment of the purification apparatus according to the present invention.
FIG. 4 is a graph showing changes over time in (a) turbidity, (b) COD, and (c) pH in the second example.
FIG. 5 is a graph showing the change over time in the residual chlorine concentration in the third example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ultraviolet lamp 2 Purifier or photocatalyst 3 Purifier holding tray 4 Water storage container 5 Stirring part 6 Filter holding tray 7 Drain pipe 8 Water purifier main body 9 Water buffer part 9a Buffer material 10 Water to be treated 11 Filtration filter 12 pH adjuster 13 Water supply mouth

Claims (6)

A water supply port for supplying water;
A filtration filter with a photocatalyst or purifier on the top surface;
Ultraviolet irradiation means for irradiating the upper surface of the filtration filter with ultraviolet rays;
Buffer the momentum of the water supplied from the water supply port, and a water flow buffer unit for gently flowing water into the filtration filter;
A water storage part for storing water that has passed through the filtration filter;
The photocatalyst or the purification agent is not fixed to the filtration filter,
The purifier comprises an adsorbent and a photocatalyst carried on the adsorbent,
The adsorbent is a solid acid mainly composed of SiO ₂ and Al ₂ O ₃ , and the chemical composition of the adsorbent is represented by H _n Al _n Si _96-n O ₁₉₂ ,
The water purification apparatus according to claim 1, wherein the photocatalyst is titanium dioxide or titanium dioxide having a surface deposited with a noble metal. A drainage pipe for keeping the water level in the water reservoir constant is provided upright on the bottom surface of the water reservoir,
The water purifier according to claim 1, wherein the entire filtration filter is immersed in water in the water storage section. A holding tray with holes on the bottom is provided,
The water purifier according to claim 1 or 2, wherein the holding tray holds the filtration filter.   The water purifier according to claim 3, wherein an upper end portion of the holding tray is positioned higher than a water level in the water storage portion. The water purifier according to any one of claims 1 to 4, wherein a pH adjuster that maintains the pH of water in a neutral region is immersed in water in the water storage section.   The water purifier according to claim 5, wherein the pH adjuster is coral stone, an alkali metal compound, or an alkaline earth metal compound.

Images