JPH08132026A - Water purifier - Google Patents

Abstract

PURPOSE: To surely remove heavy metal consisting of trace lead and the like contained in raw water to obtain safe and delicious purified water by arranging a water purifying tank packed with an aluminosilicate base inorganic ion exchanger as an adsorbent. CONSTITUTION: Raw water is forcibly fed into the 1st water purifying tank 2 housed in an outer vessel 1 of a water purifier from an inlet 6. At this time, in the 1st water purifying tank 2, a prescribed aluminosilicate base inorganic ion exchanger bed is arranged, and also if necessary, the tank 2 is packed with an adsorbent bed 4 consisting of an active carbon bed which is by plural resin frames 3, 5. After purified water from which heavy metal has been adsorbed in the 1st water purifying tank 2 is passed through the 2nd purifying tank 7 consisting of a porous hollow yarn membrane to filter out a fine floating material such as fungi, it is taken out from a discharge port 11 as purified water. In a water distributing pipe 12 in the outer vessel 1, a flow rate sensor 9 and a flow rate indication part and control part 10 are arranged between both the water purifying tanks 2, 7. In this way, heavy metal consisting of trace lead and the like, and miscellaneous bacteria and the like contained in raw water are surely removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purifier for obtaining safe and delicious water, and more particularly to a water purifier capable of removing a substance which causes a loss of safety and taste by specifying an adsorbent.

[0002]

2. Description of the Related Art Activated carbon water purifiers whose main purpose is to remove residual chlorine contained in tap water were introduced and used several years ago, but this type of water purifier is used when it is not used for a long time. It was revealed that undesired bacteria were generated inside. Therefore, a water purifier using membrane filtration such as a porous hollow fiber membrane has been developed to suppress the outflow of various bacteria generated in activated carbon, and this type has recently become the mainstream.

Recently, there has been proposed a cassette type water purifier in which an activated carbon storage unit, a separation filtration membrane storage unit, and an ion exchange resin storage unit are combined (actually, Kaikaihei 3-7).
989). In addition, though not so large in quantity, water purifiers using reverse osmosis membranes and water purifiers using natural stone, ceramics, etc. as filter media are also on the market.

[0004]

In the existing water purifier as described above, which is not subjected to membrane filtration such as a porous hollow fiber membrane, miscellaneous bacteria will proliferate if it is not used for a long time, and the initial flow of tap water There was a problem that it was leaked to.

In order to solve such problems, a water purifier for performing microfiltration with a porous hollow fiber membrane or a flat membrane, and a water purifier having an antibacterial property by attaching silver to activated carbon have been developed. It has been put on the market. Activated carbon impregnated with silver has different antibacterial properties depending on the amount of eluted silver, and there is a risk that a large amount of silver will flow out, and there is concern that its performance will be somewhat unstable.

On the other hand, the membrane filtration method is free from such a concern, and has a great feature in that it has sufficient performance for removing contaminants and the like. An adsorption mechanism using activated carbon can be further added to the membrane filtration method. In this case, by properly selecting the amount of activated carbon used and the type of activated carbon, it is possible to remove trihalomethane, harmful organic substances such as pesticides, which are dissolved in a trace amount, and a highly functional water purifier can be obtained. .

However, even with such a high-performance water purifier that combines membrane filtration and activated carbon adsorption, heavy metals such as lead, which are currently considered to be dissolved in tap water in trace amounts, are completely eliminated. Currently, it cannot be removed. To remove these heavy metals, a water purifier using a reverse osmosis membrane has been developed and shows extremely high removal ability.
There is a problem in terms of efficiency in terms of economy, and because it has a high removal performance, it also removes the mineral components required for drinking water, which has a negative effect on the taste of drinking water. There is a problem.

As a water purifier applied to a water source having various kinds of impurities, a water purifier in which a filter, activated carbon and ion exchange resin are housed in a pressure vessel has been proposed (Japanese Patent Laid-Open No. 61-257282). Gazette). However, the ion exchange resin may contain side reaction products and impurities in the manufacturing process, and these are eluted during use.

Further, when this water purifier is used for water purification of tap water, it is oxidized by a chlorine-containing oxidizing substance which is put into the tap water as a sterilizing agent, and the coloring substance produced therefor is eluted. There is a problem.

In view of the above situation, the present inventors have made intensive studies on a water purifier that solves the above-mentioned problems and can obtain safe and delicious water without containing heavy metals in the purified water. completed.

[0011]

The present invention provides a water purifier characterized by comprising a water purifying tank filled with an aluminosilicate inorganic ion exchanger and, if necessary, activated carbon as an adsorbent. is there.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The aluminosilicate-based inorganic ion exchanger used in the present invention does not contain a water-soluble organic substance unlike the conventionally used ion exchange resins, and is susceptible to oxidation by a chlorine-containing oxidizing substance. No colored substance is produced or eluted. Examples of the aluminosilicate-based inorganic ion exchanger that can be used include zeolite and celite.

The aluminosilicate type inorganic ion exchanger is
It is particularly preferable to use an acidic oxide complex having a molar ratio composition represented by the following formula from the saturated adsorption amount as a performance of removing heavy metals, particularly lead, which is the purpose of use.

Na ₂ O / K ₂ O / CaO / Al ₂ O ₃ /
SiO ₂ = 0.4~1.0 / 0.0~0.4 / 0.0~
0.5 / 1.0 / 1.5-3.0

This molar ratio composition is a composition ratio when Al ₂ O ₃ is 1.0, and when the composition deviates from this range, the adsorption amount of heavy metals such as lead is remarkably reduced.

Examples of such an aluminosilicate inorganic ion exchanger include molecular sieve 3A, molecular sieve 4A, molecular sieve 5A, and molecular sieve 13X.

The aluminosilicate type inorganic ion exchanger is
The initial adsorption performance may be inferior, but the adsorption performance will be restored if water flow is continued. According to a detailed study by the inventors,
For this phenomenon, it has been found that it is effective to subject the aluminosilicate inorganic ion exchanger to some pretreatment. That is, in particular, in the case of contacting with water at a high volume rate like a water purifier, in the initial stage of use, water may sufficiently penetrate into the inside of the aluminosilicate-based inorganic ion exchanger particles, and the dissolved substance may diffuse. There is a cause for not being able to.

To suppress such a phenomenon, 1 to 3 k
Activation by exposing to pressurized steam of g / cm ² for 5 minutes to 5 hours is effective. By such activation treatment, water sufficiently penetrates into the fine pores of the aluminosilicate inorganic ion exchanger, and the exchange groups present therein can be adsorbed from the initial stage of use. Therefore, the adsorption performance of the aluminosilicate-based inorganic ion exchanger is exhibited from the beginning of water flow.

As a method of activation, 1 to 3 kg / cm ²
Exposure to pressurized steam. To expose to such pressurized steam, an aluminosilicate-based inorganic ion exchanger may be placed in a pressure vessel, pressurized steam may be press-fitted, and after a predetermined time, it may be taken out. In this case, if the pressure is lower than the above pressure range, the activation is insufficient. On the contrary, if it is too high, no further effect is obtained and it is not economical.

The exposure time for activation may be 5 minutes to 5 hours, and may be appropriately selected within this range depending on the type of aluminosilicate inorganic ion exchanger. For example, in the case of the molecular sieve 5A, the condition of 1.5 kg / cm ² of pressurized steam for 1 hour is selected.

The particle size of the aluminosilicate inorganic ion exchanger used is preferably as small as possible from the viewpoint of adsorption ability.
If it is too small, pressure loss increases, which is not preferable.
Considering these points, the particle size is appropriately selected from the range of 0.1 to 0.5 mm.

In addition to the removal of heavy metals, it is necessary to effectively remove chlorine-containing oxidizing substances that remain in tap water and cause so-called chlorine odors, trihalomethanes that are harmful substances, and pesticides. Is preferably used in combination with activated carbon. The activated carbon is not particularly limited as long as it has performance that meets such purposes. For example, activated carbon is in the form of powder, fibrous, particulate, etc., from the raw material, natural activated carbon such as coconut shell activated carbon, bone charcoal, charcoal and pitch type, petroleum coke type, firing activated carbon such as resin and rubber, etc. The synthetic activated carbon of No. 1 is further classified into steam activation, chemical activation and the like depending on the activation method, but any of these activated carbons may be used.

However, when the activated carbon is used in a water purifier, the passing speed of the water passing through the activated carbon is very large and the pressure loss is a big problem as compared with the conditions of use of general activated carbon other than the water purifier. Become. Therefore, when it is used for a water purifier, a material having a small pressure loss, that is, a particle having relatively large particles is practically suitable. Further, many substances to be removed have relatively small molecular weights, and steam-activated coconut husk activated carbon is most practically most suitable in consideration of economical efficiency.

Silver or the like may be attached to the activated carbon in order to impart antibacterial properties.

In the water purifier of the present invention, the aluminosilicate inorganic ion exchanger or water adsorbed in a water purification tank filled with activated carbon is further filtered using a porous hollow fiber membrane. You may arrange the water purification tank of. Second
In the water purification tank, the purpose of using the porous hollow fiber membrane is to filter out microscopic suspended matters including miscellaneous bacteria contained in water. For this purpose, the larger the effective filtration area per unit volume, the better, and in this respect, the hollow fiber membrane is more efficient than the flat membrane.

The material of the porous hollow fiber membrane is not particularly limited. Examples thereof include olefin polymers such as polyethylene and polypropylene, and polysulfone.

It is particularly desirable that these porous hollow fiber membranes are hydrophilized with, for example, an ethylene-vinyl acetate-vinyl alcohol copolymer or the like in order to improve water permeability.

The water purifier may be provided with a flow meter for knowing the amount of water passing between the adsorbent treatment consisting of the aluminosilicate inorganic ion exchanger and activated carbon and the filtration treatment with the hollow fiber membrane.

Next, an example of an embodiment of the water purifier of the present invention will be described with reference to the attached FIG. The water to be purified is press-fitted from the inlet 6 into the first water purification tank 2 contained in the outer container 1 of the water purifier. The first water purification tank 2 is filled with a predetermined aluminosilicate-based inorganic ion exchanger layer and, if necessary, an adsorbent layer composed of an activated carbon layer. The water in which the heavy metals have been adsorbed in the first water purification tank is also stored in the outer container 1 via the water distribution pipe 12, and in the second water purification tank 7 made of the porous hollow fiber membranes 8, microbes and other microscopic floating. The substance is filtered and taken out from the discharge port 11 as purified water. The water pipe 12 in the outer container 1 is provided with a flow rate sensor 9 between the first and second water purification tanks.

In FIG. 1, reference numerals 3 and 5 indicate a resin frame having a mesh structure for preventing the filled adsorbent from flowing out, and reference numeral 10 indicates a display of the water purifier and a control section.

[0031]

EXAMPLES The present invention will be described in more detail below with reference to examples. [Example 1] In the water purifier shown in Fig. 1, a resin frame 5 having a nylon mesh of 150 mesh attached from the primary side was installed in the first water purification tank 2, and the adsorbent laminate 4 was made of activated carbon 450.
A resin frame 3 made of g and 100 ml of an aluminosilicate-based inorganic ion exchanger and manufactured in the same manner as the resin frame 5 was inserted so that the adsorbent did not flow out.

In the second water purification tank 7, the polyethylene porous hollow fiber membrane 8 which has been subjected to the hydrophilization treatment is fixed with a two-component polyurethane resin and one end thereof is cut and opened. The impeller-type flow rate sensor 9 is installed in the middle of the water pipe 12 that connects the water purification tanks 7 and 2.

As the aluminosilicate inorganic ion exchanger, molecular sieve 5A having the following composition was used. Na ₂ O / CaO / Al ₂ O ₃ / SiO ₂ = 0.5 /
0.5 / 1.0 / 1.85

An aqueous solution of lead chloride adjusted to have a lead concentration of 150 ppb was passed through the inlet 6 at a water flow rate of 4 l / min. The lead concentration in the outflow water was 8 ppb from the beginning of water flow to 200 liters of water, but it was 1 to 5 ppb when water was continuously flowed and 500 liters of water were flowing, and the adsorption performance was completely recovered. Further, when the water flow was continued and the lead concentration in the outflow water at the time of 7 m ³ water flow was measured, it was 1 to 5 ppb.

[Example 2] A water purifier was prepared in the same manner as in Example 1 to prepare an aluminosilicate inorganic ion exchanger.
The same molecular sieve 5A as used in Example 1
Was used after being activated with 1.8 kg / cm ² of pressurized steam for 3 hours.

A lead chloride solution adjusted to have a lead concentration of 150 ppb was passed through the inlet 6 at a water flow rate of 4 l / min. The lead concentration in the effluent when passing 200 liters is 1 to
It was 5 ppb.

[0037]

The water purifier of the present invention is composed of an aluminosilicate-based inorganic ion exchanger and an adsorbent in which activated carbon is optionally used in combination. The water purifier provided with a second water purification tank made of a hollow fiber membrane is an epoch-making water purifier in which bacteria in the water and microscopic suspended matter are removed and safe and delicious water is obtained.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a water purifier of the present invention in a partial cross section.

[Explanation of symbols]

 1 Outer Container 2 First Water Purification Tank 3,5 Resin Frame 4 Adsorbent 6 Inlet 7 Second Water Purification Tank 8 Porous Hollow Fiber Membrane 9 Flow Rate Sensor 10 Flow Rate Display and Control Unit 11 Discharge Port 12 Water Pipe

Claims (5)

[Claims] 1. A water purifier comprising a water purification tank filled with an aluminosilicate inorganic ion exchanger as an adsorbent. 2. The water purifier according to claim 1, wherein the aluminosilicate inorganic ion exchanger is an acidic oxide complex having a molar ratio composition represented by the following formula. Na ₂ O / K ₂ O / CaO / Al ₂ O ₃ / SiO ₂ =
0.4-1.0 / 0.0-0.4 / 0.0-0.5 /
1.0 / 1.5-3.0 3. The water purifier according to claim 1, which is filled with an activated aluminosilicate inorganic ion exchanger exposed to a pressurized steam of 1 to 3 kg / cm ² for 5 minutes to 5 hours as an adsorbent. 4. The water purifier according to claim 1, 2 or 3, wherein activated carbon is also used as an adsorbent. 5. The water purifier according to claim 1, wherein a second water purification tank using a porous hollow fiber membrane is arranged on the water outlet side of the water purification tank.