JPH0929237A - Water purifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively remove chlorine, dissolving ionic toxic substance, etc., by providing the first water purifying tank in which a mixture of a cation exchange resin and an active carbon is used as a filter medium and the second water purifying tank in which a hollow fiber membrane is used as a filter medium, in a water purifier in which the active carbon, the cation exchange resin and the hollow fiber membrance are used as the filter medium. SOLUTION: The first water purifying tank 2 and the second water purifying tank 7 are arranged in the main body container 1 of a water purifier and a flow rate sensor 9 and a controlling and displaying part 10 are provided between both the water purifying tanks 2 and 7. In addition, a mixture of a cation exchange resin and an active carbon is stored in the first water purifying tank 2 and a hollow fiber membrane is stored in the second water purifying tank 7 located on the downstream of the first water purifying tank, respectively as filter medium, and chlorine, trihalomethane, dissolving ionic toxic substances, agrochemicals, etc., are eliminated in the first water purifying tank 2 and bacteria and micro toxic substances, etc., are eliminated in the second water purifying tank 7. In this instance, a calcium salt type is used as the cation exchange resin, and a natural stone wherein calcium carbonate and/or soluble silicic acid are main components is filled in the first water purifying tank and/or the second water purifying tank.

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 removing substances that impair the safety and taste of water.

[0002]

2. Description of the Related Art Activated carbon is used as a filtering material in a water purifier for the purpose of purifying tap water because activated carbon adsorbs and removes residual chlorine contained in tap water.
In a water purifier that uses activated carbon as a filter medium, when the water flow is stopped for a long time after use, various bacteria propagate in the activated carbon layer,
There is a problem that miscellaneous bacteria will flow out when water is restarted.

Further, since the porous hollow fiber membrane can capture bacteria by membrane filtration, there is also known a water purifier using activated carbon in combination with the porous hollow fiber membrane as a filter material and having no problem of outflow of various bacteria. However, even in a water purifier using such a porous hollow fiber membrane as a filtering material, dissolved ionicity such as cations of heavy metals such as lead and anions such as nitrate nitrogen and nitrite nitrogen, which are eluted from water pipes At present, it is not very effective in removing harmful substances.

Regarding the removal of dissolved ionic harmful substances,
A water purifier that combines an activated carbon storage unit, a separation filtration membrane storage unit, and an ion exchange resin storage unit (No. Kaikai 3-7989), a filter stored in a container, a water purifier that sequentially passes tap water through the activated carbon and ion exchange resin ( JP-A 61-257282) is proposed, and it is known that chlorine, trihalomethane, pesticides and dissolved ionic toxic substances are removed by activated carbon, and dissolved ionic toxic substances are removed by an ion exchange resin. There is.

However, in the above proposed water purifier, when the ion exchange resin is arranged on the upstream side of the activated carbon, the ion exchange resin is oxidatively decomposed by the effect of chlorine contained in tap water and cannot be completely removed by the activated carbon. The decomposed product may flow out and cause odor in the filtered water. Further, when the ion exchange resin is arranged on the downstream side of the activated carbon, decomposed products and low molecular weight substances contained in the ion exchange resin flow out to generate odor in the filtered water.

[0006]

The object of the present invention is to use chlorine, trihalomethane, pesticides, dissolved ionic toxic substances and bacteria contained in tap water by using activated carbon, hollow fiber membranes and cation exchange resins as filter media. It is intended to provide a water purifier that obtains safe and delicious water from which water etc. has been effectively removed.

[0007]

The present invention provides a water purifier using activated carbon, a cation exchange resin and a hollow fiber membrane as a filtering material, and a first water purification tank using a mixture of the cation exchange resin and activated carbon as a filtering material. And a second water purification tank having a hollow fiber membrane arranged downstream thereof as a filtering material.

The water purifier of the present invention comprises a first water purification tank and a second water purification tank arranged downstream of the first water purification tank. The first water purification tank filters a mixture of a cation exchange resin and activated carbon. The hollow fiber membrane is stored as a filtering material in the second water purification tank.

In the first water tank of the water purifier of the present invention, chlorine, trihalomethane, dissolved ionic toxic substances, pesticides, etc. are removed by a mixture of cation exchange resin and activated carbon, and the second water tank is hollow. Bacteria, fine harmful substances, etc. are removed by a thread film.

In the first water purification tank, the activated carbon removes chlorine contained in the tap water of the raw water which oxidizes and decomposes the cation exchange resin, and at the same time, adsorbs and removes decomposition products and low-molecular substances contained in the cation exchange resin. Then, the cation exchange resin can be effectively functioned to sufficiently remove the dissolved ionic toxic substance, and filtered water having no odor and the like due to coloring by the oxidative decomposition product of the cation exchange resin can be obtained.

The cation exchange resin used in the water purifier of the present invention may be either a strongly acidic cation exchange resin or a weakly acidic cation exchange resin. In tap water, for example, lead pipes used in water pipes, lead, etc. Since the heavy metal cations are dissolved and most of them are dissolved as neutral salts, it is preferable to use a strong acid cation exchange resin that decomposes and adsorbs the neutral salts.

The cation exchange resin preferably has an ionic type of a calcium salt type. By using the calcium salt type cation exchange resin, the calcium ions released into the filtered water by ion exchange can be filtered. It is said to give an odor, and since it is replenished to the human body by drinking, it is possible to obtain filtered water which is preferable from a health standpoint.

The activated carbon used in the water purifier of the present invention is
It is not particularly limited as long as it is an activated carbon that can be usually used in a water purifier, coconut husk, bone, natural activated carbon such as wood,
Pitch-based, petroleum coke-based, resin or rubber-based synthetic activated carbon and the like can be mentioned, and activated carbon may be activated by any method such as steam activation or chemical activation. Further, it may be in any form such as powder, granules and fibres. Further, the activated carbon may be one in which an antibacterial metal such as silver is attached by plating or the like.

As the activated carbon used in the water purifier of the present invention, 2
It is also possible to mix and use more than one kind, and the fact that the activated carbon is a mixture of two or more types of activated carbon broadens the range of adsorption capacity and expands the range of correspondence to various substances contained in tap water to improve the adsorption life. However, it is preferable to balance with other activated carbon or cation exchange resin to be mixed.

In the water purifier of the present invention, it is necessary that the filter material of the first water purification tank is a mixture of cation exchange resin and activated carbon, and the mixture of cation exchange resin and activated carbon has the following formula. It is preferable that the mixture has a satisfactory mixing ratio C / R. 1 ≦ C / R ≦ 8 where C is the activated carbon weight (g) and R is the cation exchange resin volume (ml).

When the mixture of cation exchange resin and activated carbon is a mixture having a mixing ratio C / R satisfying the above formula,
Since the adsorption capacities of the cation exchange resin and the activated carbon are almost the same and there is no significant difference in the adsorption life, it is possible to avoid incomplete adsorption due to the reduction of the adsorption capacity of only one of the mixtures.

In the water purifier of the present invention, a hollow fiber membrane is used as a filtering material in the second water purifying tank, but the hollow fiber membrane used in the water purifier of the present invention is a porous hollow that can be used in ordinary water purifiers. The fiber membrane is not particularly limited as long as it is a polyolefin-based hollow fiber membrane such as polyethylene or polysulfone-based, and is hydrophilized with an ethylene-vinyl alcohol copolymer or polyvinyl alcohol. It is also preferable that the hollow fiber membrane is hydrophilized in order to improve water permeability.

Also, in the water purifier of the present invention, calcium carbonate and / or
Alternatively, natural stone mainly composed of soluble silicic acid can be filled, and a small amount of calcium carbonate and / or soluble silicic acid which is eluted in the filtered water gives the taste of natural water.

The water purifier of the present invention is provided with the above-mentioned first water purification tank and second water purification tank, but between the first water purification tank and the second water purification tank, there is a flow sensor or a constant flow valve and a pressure switch. It is preferable to provide detection means, and by providing these means at positions where the influence of the pressure loss of the filtration media of both the first water purification tank and the second water purification tank is small, the flow rate is integrated by the flow rate sensor or at a constant flow rate. It is possible to grasp the life of the filter medium in the first water purification tank and the second water purification tank from the cumulative operating time of the pressure switch that can detect that the water is being discharged. The signal from the flow sensor of the detection means or the pressure switch is converted into light or sound and displayed on the control and display unit to indicate the life state of the filter medium.

[0020]

[Function] By using the mixture of the cation exchange resin and the activated carbon as the filter material of the first water purification tank in the water purifier of the present invention, the cation exchange resin and the activated carbon exert their functions without being hindered, Chlorine, trihalomethane, dissolved ionic toxic substances, pesticides, etc. are removed, and filtered water with no coloring or odor is removed, and bacteria and fine toxic substances are removed by the hollow fiber membrane of the filter material of the second water purification tank. Get safe, delicious water.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings.

(Embodiment 1) FIG. 1 is a sectional view of an example of a water purifier according to the present invention.

In the water purifier, the first water purification tank 2 and the second water purification tank 7 are arranged in the main body container 1, and the first water purification tank 2 and the second water purification tank 2 are arranged.
A flow rate sensor 9 and a control and display unit 10 between the water purification tanks 7.
Are provided and communicate with each other through water pipes. At the bottom of the first water purification tank 2, a tap water inlet 6 for raw water is provided.
The filtered water flowing out from the upper part of the water purification tank 2 passes through the flow rate sensor 9 and flows in from the bottom part of the second water purification tank 7 into the second water purification tank 7
Out of the upper part of the water and is discharged from the discharge water outlet 11 as purified water. Signal control and display unit 1 by the flow sensor 9
0 is provided so that it can be seen from the outside of the main body container 1.

As the calcium salt type cation exchange resin for the filter material of the first water purification tank 2, Amberlite IR-120 is used.
B (a cation exchange resin manufactured by Organo Corporation) in the form of calcium salt was used by the following method.

Amberlite IR-120B was placed in a 1-liter glass funnel and 1.5 liters of 4N hydrochloric acid aqueous solution (about 3 times equivalent amount of ion-exchange resin exchange capacity, the number of equivalents in parentheses below is the exchange capacity of counter-ion exchange resin). Was passed at a water flow rate of 200 ml / min. Then deionized water 1
After washing 0 liter of water with a water flow rate of 200 ml / min and washing, 2 liter of a 3N sodium hydroxide aqueous solution (about 3 times equivalent) was passed at a water flow rate of 200 ml / min to obtain an ion exchange resin. The ionic form of was changed to the sodium salt form.

Further, 10 liters of ion-exchanged water is added to 20
After washing by passing water at a water flow rate of 0 ml / min,
After passing 4 liters of a 4N hydrochloric acid aqueous solution (about 3 times equivalent), 10 liters of ion-exchanged water was passed for washing. Then, 1 liter of a 3 mol / liter calcium chloride aqueous solution (about 3 times equivalent) was passed at a water flow rate of 100 ml / min, and 10 liters of ion-exchanged water was passed at a water flow rate of 200 ml / min. Washed. The ion type of the obtained ion exchange resin was converted to a calcium salt type of 1.92 equivalents / liter by the measurement of the calcium ion concentration by the chelate titration method of the aqueous solution of calcium chloride and the flowing solution of the ion exchanged water. It was

As the activated carbon of the filter material of the first water purification tank 2, Kuraray Coal T-SB48 / 100 (activated carbon manufactured by Kuraray Chemical Co., Ltd.) was used.

The first water purification tank 2 is provided with a support 3 below which a nylon mesh of 150 mesh is attached to a resin frame, and a filtration material comprising a mixture of 300 ml of the calcium salt type cation exchange resin and 450 g of activated carbon. 5, a support 4 having the same structure as the support 3 was provided above so that the filtering material 5 would not flow out.

As the hollow fiber membrane 8 of the filter material of the second water purification tank 7, a porous hollow fiber membrane made of hydrophilic polyethylene is used, and the end of the hollow fiber membrane is fixed with a two-component polyurethane resin in an open state. And stored in the second water purification tank 7.

An impeller type flow rate sensor 9 is provided in the middle of the water pipe connecting the first water purification tank 2 and the second water purification tank 7, and the flow rate is controlled by the output signal of the flow rate sensor 9 and the control unit of the display unit 10 controls the flow rate. The life of the filter material is indicated by adding up.

The water purifier thus constructed was subjected to a water flow test at a water flow rate of 4 liters / minute, and the following measurements were carried out.

(1) Residual Chlorine Removal Ability The residual chlorine concentration of discharge water when 8000 liters of water containing 2.0 ± 0.2 ppm of chlorine was passed was measured by the o-tolidine method.

(2) Sterilizing ability Pseudomonas diminuta IFO1
The number of bacteria in the discharged water was measured when 6 liters of water containing 4213 1.7 × 10 ⁷ cells / ml was passed.

(3) Lead removal capacity The lead concentration in discharge water was measured when 8000 liters of a lead chloride aqueous solution of 150 ppb was passed.

(4) Removal capacity of trihalomethane: An aqueous solution prepared by adjusting chloroform to 60 ppb is used as 8000.
The chloroform concentration of the discharged water when liter was passed was measured.

(5) Filtration Material Life Display The signal of the flow rate sensor was displayed by setting the life of the filtration material at the time when the cumulative flow rate was 8000 liters, and the cumulative flow rate at the end of life was measured by a commercially available cumulative flow meter. .

The results of the water flow test of the water purifier are shown in Table 1. The water purifier of this example showed a high removal ability for residual chlorine, bacteria, lead and trihalomethane.
Further, as can be seen from the results of the filter medium life display, the flow rate measured by the flow rate sensor and the flow rate actually measured by the commercially available integrating flowmeter were almost the same, and accurate measurement was possible by the flow rate sensor.

(Embodiment 2) The activated carbon of the filter medium 5 of the first water purification tank 2 in the water purifier of Embodiment 1 was replaced with Kuraray Coal TS.
A water purifier prepared in the same manner as in Example 1 was used, except that B48 / 100 (activated carbon manufactured by Kuraray Chemical Co., Ltd.) and low-activated carbon were mixed in a weight ratio of 1: 1. A water test was conducted and the results are shown in Table 1.

The water purifier of this example showed a high removal ability for both residual chlorine and bacteria, and a slight reduction in lead removal ability, but a high removal ability for trihalomethanes.

[0040]

[Table 1]

(Example 3) A water purifier manufactured in the same manner as in Example 1 except that 200 g of limestone was added to the mixture of the filter media 5 in the first water purification tank 2 in the water purifier of Example 1 was used by Nagoya City Waterworks. The same water flow test as in Example 1 was performed using water,
The results are shown in Table 2.

The water purifier of this example showed a high removal ability for residual chlorine, bacteria, lead and trihalomethane. The calcium ion concentration measured by the titration method was 6.7 mg / liter in the tap water of the raw water, but the calcium ion concentration increased in the discharged water.

[0043]

[Table 2]

[0044]

EFFECTS OF THE INVENTION The water purifier of the present invention is a combination of a filter material composed of a mixture of a cation exchange resin and activated carbon and a filter material composed of a hollow fiber membrane. , It is possible to effectively remove dissolved ionic harmful substances, bacteria, etc. Also, it is possible to increase calcium ions by adding natural stones containing calcium carbonate and / or soluble silicic acid as a main component, which is safe and delicious. Allows you to get water. Further, by making it possible to detect the life of the filter medium, it is possible to further enhance safety and efficiently exhibit the removal ability.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example of a water purifier of the present invention.

[Explanation of symbols]

 1 Main Container 2 First Water Purification Tank 3 Support 4 Support 5 Filter Material 6 Raw Water Inlet 7 Second Water Purification Tank 8 Hollow Fiber Membrane 9 Flow Sensor 10 Control and Display 11 Discharge Water Outlet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication C02F 1/68 520 C02F 1/68 520K 530 530B 540 540A 540C 540D (72) Inventor Masahiko Taneike Tokyo 2-3-19 Kyobashi, Chuo-ku Mitsubishi Rayon Co., Ltd.

Claims (6)

[Claims] 1. A water purifier using activated carbon, a cation exchange resin and a hollow fiber membrane as a filter medium, wherein a first water tank using a mixture of a cation exchange resin and activated carbon as a filter medium and a hollow arranged downstream thereof. A water purifier characterized by comprising a second water purification tank using a fiber membrane as a filtering material. 2. The water purifier according to claim 1, wherein the cation exchange resin is a calcium salt type. 3. The water purifier according to claim 1, wherein the activated carbon is a mixture of two or more types of activated carbon. 4. A mixture of a cation exchange resin and activated carbon is a mixture having a mixing ratio C / R satisfying the following formula.
Water purifier as described. 1 ≦ C / R ≦ 8 where C is the activated carbon weight (g) and R is the cation exchange resin volume (ml). 5. The water purifier according to claim 1, wherein the first water purification tank and / or the second water purification tank is filled with natural stone containing calcium carbonate and / or soluble silicic acid as a main component. 6. The water purifier according to claim 1, wherein a flow sensor, or a constant flow valve and a pressure switch are provided between the first water purification tank and the second water purification tank.