JPH10174968A - Water purifying apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove not only water-soluble toxic substances but also turbid components in the water to be purified by capturing even organic matter with large particle shape for fixing a photocatalyst on the upper face of micro- filtration filter and decomposing the organic matter while spending time. SOLUTION: A photocatalyst 2 so processed as to be a granular shape is fixed on the upper face of a micro-filtration filter 1 arranged in the horizontal direction, the filter 1 is made detachable from the apparatus main body, an ultraviolet lamp 2 is so installed as to radiate ultraviolet rays to the photocatalyst 2 on the upper face of the filter 1, and water to be treated is supplied from the upper part of the filter, filtered by gravity, and made to flow out under the filter 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purification device used for drinking water, bath water, washing water, water in a goldfish breeding aquarium, and the like.

[0002]

2. Description of the Related Art As a conventional method for purifying harmful substances dissolved in water, a method of adsorbing undesired odors, tastes, dirts, etc., such as lime, moldy odor, and trihalomethane, dissolved in water using activated carbon is generally used. It is.

[0003] In the water purification method using a photocatalyst, a method of suspending a powdery photocatalyst in treated water to recover powder irradiated with ultraviolet rays, a method of coating the inner surface of a glass water passage with the photocatalyst, and the like have been proposed. ing.

[0004]

In the method of adsorption using activated carbon as described above, the adsorption performance gradually deteriorates, and the amount of adsorption eventually becomes saturated.

On the other hand, in the water purification method using a photocatalyst, the purification performance is not lost unlike activated carbon. However, in the method of suspending the powdery photocatalyst, although the contact efficiency between the photocatalyst and water is good and the decomposition efficiency is good, a means for recovering the powdery photocatalyst is required.

Further, in the method of coating the water channel made of glass with a photocatalyst, a means for recovering the photocatalyst is unnecessary, but the contact efficiency between the photocatalyst and water is poor, and a sufficient decomposition efficiency cannot be obtained. Further, in such a method, the organic turbid component having a relatively large particle size cannot be sufficiently decomposed simply by passing through the purification section.

[0007] In particular, in the decomposition by the photocatalyst, the substance to be purified is surely caught, and unless sufficient decomposition time is given by the photocatalyst, the substance to be purified is changed to another harmful substance having a small molecular weight. It can cause secondary contamination. As a solution to this problem, a method of coating the filter with a photocatalyst is conceivable. However, if the filter is not made of an inorganic material such as a ceramic, there is a problem that the filter itself is decomposed by the photocatalyst.

[0008]

According to the present invention, in order to solve the above problems, a photocatalyst or a composite of a photocatalyst and an adsorbent is processed into a powder, granule, ball, or the like, and is processed only on the upstream surface of the filtration filter. It is fixed and disposed so that an ultraviolet lamp irradiates the photocatalyst. Therefore, even if an organic material other than an inorganic material is used for the filter, the contact between the photocatalyst and the filter is close to the point contact, so that the photocatalyst does not decompose the filter itself, and is also used for a flexible filter such as a non-woven cloth or sponge. The filter can be used repeatedly if the inorganic substance that has been taken out and is attached to the filter is washed away or the inorganic substance is washed out by performing an operation such as backwashing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a purifying apparatus according to the present invention will be described with reference to the drawings.

<First Embodiment> FIG. 1 is a sectional view of a water purification apparatus according to a first embodiment of the present invention. In FIG. 1, 1
Is a plate-shaped microfiltration filter, and the microfiltration filter 1 is a flexible sponge-like material made of a polymer material, and has an average pore diameter of 1 μm to 1 mm. Reference numeral 2 denotes a granular photocatalyst which is evenly distributed and fixed on the upper surface of the microfiltration filter 1. As the photocatalyst 2, ST-Bll of Ishihara Sangyo Co., Ltd. is used. However, the particle size of the photocatalyst 2 may be small, such as powder or granule, or may be a large ball, or a photocatalyst that has a photocatalyst carried on the surface of an adsorbent mainly composed of silica instead of the photocatalyst. May be used.

The microfiltration filter 1 is detachable from the water purification section main body 8 and has a photocatalyst 2 in a cartridge 11 having a large number of holes for allowing water to be treated to pass through the bottom surface thereof.
Arrange so that the surface on which is fixed faces upward. In addition, the overflow pipe 6 is erected in the water storage tank 7 to keep the water level in the water storage tank 7 constant, and the cartridge 11 is disposed in the water storage tank 7 so that the entire microfiltration filter 1 is immersed. In addition,
The side surface of the cartridge 11 has no hole, and the upper end of the side surface is formed to be higher than the water level in the water storage tank 7 defined by the overflow pipe 6. Further, the ultraviolet lamp 3 is installed at a position higher than the water surface of the water storage tank 7 so as to irradiate the photocatalyst 2 on the upper surface of the microfiltration filter 1.

The water to be treated sent from a pump or the like (not shown) is supplied to the upper surface of the microfiltration filter 1 in the cartridge 11 from the water inlet 4, and is subjected to gravity due to a water level difference between the cartridge 11 and the water storage tank 7. Go through photocatalyst and filter. At this time, the turbid component having a large particle size is collected on the upper surface of the microfiltration filter 1, the dirt component dissolved in the water to be treated is collected on the photocatalyst surface, and the organic matter among the collected substances is excited by an ultraviolet lamp. Photocatalyst decomposes water and harmless substances such as inorganic carbonic acid and purifies the water. On the other hand, non-decomposable inorganic substances such as sands and mineral components are originally harmless. Even if they are deposited on the microfiltration filter 1, if the cartridge 11 is taken out from the main body 8 and washed off,
The microfiltration filter 1 can be used repeatedly.

FIGS. 3 to 6 show the turbidity, the COD, the number of common bacteria and the water in the goldfish tank using the goldfish tank equipped with the purification apparatus shown in the first embodiment and a commercially available bio-type purification apparatus, respectively. It is a change with time of the nitrite nitrogen concentration. The experimental conditions were as follows: the water tank was 60 liters, and seven fish were raised in each tank, and the water temperature was maintained at 25 to 35 ° C. In the first embodiment, the ultraviolet lamp is always turned on. In the case of the bio-type, all of the purification items are bad, and unless the bio-filter is washed once a month, organic dirt is heavily deposited on the filter itself. In the purification device of the first embodiment, all the purification items are sufficiently purified,
There is almost no accumulation of dirt on the microfiltration filter 1 itself.

<Second Embodiment> FIG. 2 is a sectional view of a tap water drinking water purifying apparatus according to a second embodiment of the present invention. FIG.
In the figure, reference numeral 1 denotes a microfiltration filter made of a cylindrical inorganic material or a polymer material, and a particulate photocatalyst 2 is fixed on the outer peripheral surface of the microfiltration filter 1. The microfiltration filter 1 has a cylindrical glass 10
The hollow fiber filter 9 is disposed in a cylindrical space inside the microfiltration filter 1. Instead of the photocatalyst 2, a photocatalyst carried on an adsorbent containing silica as a main component may be used.

A ring-shaped ultraviolet lamp 3 is provided in the outer space of the cylindrical glass 10, and irradiates the photocatalyst 2 through the glass 10. Water supplied from the water inlet 4 by tap water pressure or a pump or the like passes through a water passage formed between the cylindrical glass 10 and the microfiltration filter 1 and passes through the photocatalyst and the microfiltration filter. At this time, dirt having a relatively large particle size is collected by the microfiltration filter 1, and water-soluble dirt is collected on the photocatalyst surface.

The excitation by the ring-shaped ultraviolet lamp 3 causes the photocatalyst 2 to oxidize and decompose the collected organic dirt such as residual chlorine and trihalomethane into water and inorganic carbonic acid and purify it without kiln. Sterilizes bacteria in water by antibacterial action. Iron rust and the like having a small particle size that cannot be collected by the microfiltration filter 1 are collected by a hollow fiber filter further downstream, and exit from the drain port 5 as drinking water.

As the amount of purified water increases, non-decomposable inorganic dirt gradually adheres to the microfiltration filter 1 and the hollow fiber filter 9 to cause a pressure loss and a decrease in the flow rate. By performing backwashing and removing the attached inorganic substance from the water injection port 4, the life can be extended.

[0018]

According to the first aspect of the present invention, since a photocatalyst is immobilized on the upper surface of the microfiltration filter, even large-sized organic substances can be collected and decomposed over time. In addition, turbid components in the water to be purified can be purified. In addition, since the photocatalyst is granular, the contact between the microfiltration filter and the photocatalyst is small, and even if an organic material such as non-woven cloth or sponge is used for the microfiltration filter, the risk of deterioration is reduced. It can be used for a filtration filter, and even if inorganic substances that do not decompose accumulate on the surface of the microfiltration filter, the microfiltration filter can be used repeatedly if it is taken out and rinsed out, eliminating the need to replace the microfiltration filter.

According to the second aspect, the overflow mechanism can maintain the water level at which the microfiltration filter covers the water at all times, and can provide a sufficient contact time between the microfiltration filter and the water to be purified. The efficiency is good. In addition, even if the water to be purified is retained, the bacteria can be prevented from growing due to the antibacterial action of the photocatalyst.

According to the third aspect, since the ultraviolet lamp can be installed in an independent space with little water vapor, dirt such as calcium contained in water adheres to the surface of the ultraviolet lamp and the intensity of the ultraviolet light is reduced. There is no.

According to the fourth aspect of the invention, the maintenance of the microfiltration filter can be reduced by backwashing the non-decomposable inorganic substance deposited on the microfiltration filter and discharging it from the apparatus.

According to the fifth aspect, the purification efficiency by the photocatalyst is improved by supporting the photocatalyst on the adsorbent mainly composed of silica, which easily transmits ultraviolet light, and the adsorbent adsorbs contaminants. The intermittent operation of the ultraviolet lamp becomes possible, and the life of the ultraviolet lamp is extended. Further, even if the water to be treated contains a pollutant having a high molecular weight and a secondary pollutant is generated by decomposition, the secondary pollutant is adsorbed by the adsorbent, so that the secondary pollutant is not discharged.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a water purification device of the present invention.

FIG. 2 is a cross-sectional view showing a second embodiment of the water purification device of the present invention.

FIG. 3 is an explanatory diagram showing a turbidity change in a goldfish tank of the water purification device of FIG. 1 and a commercially available bio-type water purification device.

FIG. 4 is an explanatory diagram showing a COD change in a goldfish water tank between the water purification device of FIG. 1 and a commercially available bio-type water purification device.

FIG. 5 is an explanatory diagram showing a change in the number of general bacteria in a goldfish tank of the water purification device of FIG. 1 and a commercially available bio-type water purification device.

FIG. 6 is an explanatory diagram showing a change in nitrite nitrogen concentration in a goldfish water tank of the water purification device of FIG. 1 and a commercially available bio-type water purification device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Precision filtration filter 2 Photocatalyst 3 Ultraviolet lamp 4 Injection port 5 Drainage port 6 Overflow pipe 7 Water storage tank 9 Hollow fiber membrane filter 10 Ultraviolet transmission glass

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 1/00 C02F 1/00 L 1/32 1/32

Claims (5)

[Claims] 1. A water treatment system comprising a microfiltration filter removably provided from an apparatus main body, a particulate photocatalyst fixed to an upper surface of the microfiltration filter, and an ultraviolet lamp for irradiating the photocatalyst with ultraviolet rays. Water is supplied from above the filter, and the water is purified by passing through the microfiltration filter by gravity. 2. A water storage tank for storing the water to be treated, an overflow mechanism for keeping the water level of the water storage tank constant, and a flow of the water to be treated into the water storage tank from the bottom covering the side surface of the microfiltration filter. The water purification device according to claim 1, further comprising a cartridge for causing the water purification device. 3. A microfiltration filter formed in a cylindrical shape, a particulate photocatalyst immobilized on the outer surface side of the microfiltration filter, an ultraviolet-transparent glass containing the microfiltration filter, and the ultraviolet-transparent glass And an ultraviolet lamp for irradiating the photocatalyst with ultraviolet rays through the filter, and purifying the water to be treated from between the microfiltration filter and the ultraviolet light transmitting glass so as to pass through the microfiltration filter for purification. A water purification device characterized by the following. 4. The water purification apparatus according to claim 1, wherein a water passage for backwashing the microfiltration filter is formed. 5. The water purifier according to claim 1, wherein the photocatalyst comprises a composite catalyst in which a photocatalyst is supported on the surface of an adsorbent containing silica as a main component.