JPS58131187A - Pasteurizing purifier for water - Google Patents

Abstract

PURPOSE:To obtain the pasteurizing purifier for water which enables to exude silver exhibiting the sufficient effect of pasteurization during the suspension of water supply but which substantially suppresses the exudation of silver during water supply, by arranging granular active carbon in a passage for the main current of water and the fibers of silver-inserted active carbon in a passage for the sub-current of water inside the water purifier. CONSTITUTION:A cartridge 2 is received in the vessel 1 of a water purifier so that granular active carbon 6 is arranged in a passage for the main current of water while the fibers 5 of silver-inserted active carbon is arranged in a passage for the sub-current of water. Foamed urethane bodies 7 or the like are provided at the upper and lower ends of the cartridge 2 to inhibit the outflow of the granular active carbon. Water is let mainly flow through the layer 6 of the granular active carbon and pasteurized by the exudation of silver from the passage for the sub-current. Accordingly, chloric ion, etc. only are adsorbed, and purified water into which silver is not substantially exuded is obtained. During the suspension of water supply, silver ion is exuded from the fibers 5 of silver-inserted active carbon and dispersed into the layer 6 of granular active carbon to perform the pasteurization of water throughout the interior of the water purifier.

Description

[Detailed description of the invention] The present invention relates to a sterile water purifier.

Simple water purifiers filled with activated carbon are widely used in households to remove chlorine, putrid odors, and carcinogenic substances from tap water. However, although the water purifiers currently available on the market eliminate the chlorine odor, they also remove the sterilizing effect of chlorine, allowing bacteria to grow inside the water purifier, and the number of bacteria can reach 10,000/cc. .

In order to improve these drawbacks, attempts have been made to sterilize bacteria in water purifiers using silver sterilization methods.

It has been proposed to impregnate activated carbon with silver or to plate the inside of the water purifier with silver.

Although those specific technologies are shown in numerous applications,
For example, Jitko 52-1745 and Special Publication 54-42180
As shown in Figure 2, activated carbon and a silver compound are used, and both are arranged in series with respect to the direction of water flow. That is, in the conventional technology, running water comes into contact with silver-impregnated activated carbon (2), so silver ions are eluted into drinking water as well. In particular, when water starts flowing after water stops, silver ions eluted during the water stop period flow out in high concentrations, and even during steady water flow, essentially unnecessary silver ions flow out. There is. However, silver ions are required in water purifiers to prevent the proliferation of bacteria, etc. in the water in which chlorine ions have been adsorbed by activated carbon when the water is stopped, and their presence in purified water collected for use is unnecessary. It is. Therefore, these problems cannot be fundamentally solved with the structures of water purifiers that have been proposed so far.

As a result of intensive research to solve this problem, the inventor has found that almost no silver is eluted in the flowing water (10 ppb or less).
Concentration (100 ppb) that shows sufficient sterilizing effect when water is still
We have come to invent an ideal water purifier in which silver (above) is eluted.

That is, the present invention is a sterilized water purifier characterized in that granular activated carbon is arranged in the main flow area of water, and silver-impregnated activated carbon fibers are arranged in the side flow area of water.

(3) To be more specific, in the above-mentioned sterilized water purifier, granular activated carbon is filled with the central axis area of the container as the main water flow area (-1 The outer peripheral area of the central axis area is used as the secondary water flow area). The central axis area of the water purifier and container is filled with silver-impregnated activated carbon fibers as a secondary water drainage area, and the outer peripheral area of the central axis area is the main flow area of water.] To provide a water purifier filled with granular activated carbon.

The main flow area of water in the present invention is the area where water mainly flows in the water purifier, and the side flow area is the area where a much smaller amount of water flows than the main flow area. . These flow areas can be easily formed by adjusting the openings in the distribution plate of the raw water supply port provided in the water purifier. Alternatively, it can be formed simply by adjusting the packing density of activated carbon fibers and granular activated carbon, which will be described later. Therefore, if granular activated carbon without silver impregnation is placed in the main flow area and silver-impregnated activated carbon fibers are placed in the side flow retreat area, water will mainly pass through the granular activated carbon layer without silver impregnation during water flow, and only chlorine ions, etc. will be removed. It is possible to obtain treated water with almost no (4) elution of adsorbed silver ions.

On the other hand, when the water is stopped, the snail ions are eluted from the silver-impregnated activated carbon fibers and diffused into the granular activated carbon layer, making it possible to sterilize the entire interior of the water purifier. When water flow is resumed, safety can be further increased by discharging an appropriate amount of water to discard the eluted silver ions. As described above, the present invention uses a novel structure in which activated carbon and silver-impregnated activated carbon are arranged in parallel in the water flow direction, and the above-mentioned problems are solved.

Various ways can be considered as to how to provide the main water flow area and the secondary flow drainage area in the water purifier depending on the needs, but the most practical way is to use a cylindrical or prismatic central axis area as shown in the figure. This is a structure in which the main flow area is the main flow area and its outer peripheral area is the secondary flow relief area, or a structure in which the central axis area is the secondary flow relief area and the outer peripheral area is the main flow area.

Any activated carbon fiber can be used as the activated carbon fiber used in the present invention, but in particular activated carbon fiber with a specific surface area of 1500"
7g or more is preferable. If the surface area is small, the silver supported in the micropores will be difficult to elute (5), and the concentration will decrease, resulting in a decrease in the bactericidal effect. Furthermore, if the specific surface area is small, the pore volume is also usually small, so it is not possible to increase the amount of silver attached. If it is 1500 trt/or more, the pore volume is large and the pore diameter is appropriate, so the amount of copper bathed out increases. Furthermore, since activated carbon fibers have an extremely large outer surface area of about 100 times that of granular carbon, they have the effect of increasing the amount of silver eluted compared to granular carbon.

Next, the amount of silver impregnated on the activated carbon fiber is 0.5~
10% by weight is good, but considering silver elution concentration, lifespan, etc., the most preferable is 2 to 5% by weight.Also, it is desirable that the silver compound to be impregnated is a sparingly soluble one, and silver chloride or silver oxide is convenient. It is preferable that it can be manufactured in Silver oxide is most preferable because the amount of copper released from the bath does not decrease due to the influence (solubility product) of chlorine ions in tap water. Silver is easily impregnated by simply immersing activated carbon fibers in an aqueous solution of silver nitrate, and the fibers are quickly adsorbed. This was mixed with NaCl, HC
I.

Activated carbon fibers impregnated with silver chloride or silver oxide can be obtained by treatment with H2O2 or the like. Silver oxide or silver chloride (6) The choice between silver oxide and silver chloride can be made depending on the water quality of the water supply. That is, the desired purpose can be achieved by impregnating silver oxide in water with a large amount of chlorine ions, and by using silver chloride in water with a small amount of chlorine ions.

It is not impossible to use silver-impregnated granular activated carbon instead of silver-impregnated activated carbon fibers, but the granular carbon mixes with each other due to vibration during water flow, making it difficult to arrange activated carbon layers with and without silver impregnation separately. I can't.

In addition, granular activated carbon has a limited outer surface area, and as silver
There is a limit to the amount of silver that can be attached by weight, and even if it is supported more than this, the silver compound will simply be attached to the surface and will easily peel off.

Activated carbon fibers can be used in the form of long fibers, short fibers, felt, or cloth, but cloth or felt is most desirable from a work standpoint. The density of activated carbon fibers affects water permeability, so it can be determined by considering the structure of the distribution plate, the packing density of granular activated carbon, etc.

The present invention will be explained below with reference to the drawings.

Figure 1 shows a structure of the water purifier of the present invention in which the central axis area of the container is the main water flow area (7) and the outer peripheral area is the secondary water flow area.
Give an example. The water purifier container 1 houses a cartridge 2 containing activated carbon, and also has an inlet 3 for raw water and an outlet 4 for purified water. In this example, the IJ edge 2 has silver-impregnated activated carbon fibers 5 in its central shaft region, and granular activated carbon in its outer peripheral region. Further, urethane foam 7 is provided at the upper and lower ends of the cartridge to prevent the granular activated carbon from flowing out, and especially the urethane foam at the lower end also has a function of a water distribution plate to some extent. Of course, it is free to provide another distribution plate in place of the urethane foam. Due to this structure, water mainly flows through the granular activated carbon layer in the central region, and the necessary silver ions are eluted from the outer peripheral region to perform a sterilizing effect.

FIG. 2 shows another example of the structure of the water purifier of the present invention, in which the central axis area of the container is used as a secondary water flow area, and the outer peripheral area is used as the main flow area. In the structure shown in FIG. 2, the cartridge container 2
A distribution plate 8 is provided at the lower end in order to make the outer peripheral area of the main flow area the main flow area. Various structures can be used for the distribution plate 8 and the filter 7.5 For example, the filter may be a cloth-like one in addition to the above-mentioned urethane foam (8) or Ohm.7 Parts not specifically explained are the same as in Fig. 1. be.

This will be explained below using examples.

Example 1, Comparative Examples 1 to 4 Specific surface $1 manufactured using phenolic resin fiber as raw material
After immersing activated carbon fiber felt of 2000"/cm in silver nitrate solution to support 3.0% by weight of metallic silver, H2O2
It was oxidized with water to obtain silver oxide-impregnated activated carbon fiber felt (A). 0) was placed on the peripheral wall of a water purifier cartridge with an internal volume of 100 m/cm, and the cartridge, in which the center core was filled with 21 f of coconut grain-like activated carbon, was loaded into the water purifier, and a water purification test was conducted. The Ag concentration during water flow, the silver concentration in the cartridge, and the number of bacteria were measured.

As a comparative example, the surface area was 1000 d using the same method as in (a).
Copper-added charcoal (b) was obtained in which 3.0% by weight of silver oxide was supported on granular activated carbon (1). (b) to the cartridge peripheral wall 3y
A water purification test was also carried out on a cartridge whose central core was filled with 249 particles of silver-impregnated activated carbon (9) Similarly, 3 g of polyester felt (C) impregnated with 3% by weight of silver oxide was applied to the peripheral wall and to the central core. A water purification test was also conducted on a cartridge filled with 21 g of granular activated carbon and a cartridge whose inner wall was plated with silver (metallic silver 1011i/cartridge) by silver mirror reaction.

The results are shown in Table 1.

Collection V: Margin (1,0) As shown in Experiment Report (1), in the cartridge of the present invention, almost no plate was eluted during water flow, and sufficient sterilization effect was obtained when water was stopped.

Example 2 Carbonizing and activating polynosic fiber to obtain a specific surface area of 1500'
/g of activated carbon fiber felt was obtained. 4. Adding silver oxide to this as a metal. A silver-impregnated activated carbon fiber felt (e) was obtained by supporting Q wt%. (e) After filling 3f in the same manner as in (a) of Example 1 to make a cartridge, add 517 ml of tap water.
Water was passed through the tube at a rate of 3,001 minutes per minute, and after being allowed to stand still for 16 hours, water flow was resumed at a slow flow rate of 100 L/minute.

Changes in copper elution concentration in the effluent water over time after restarting were measured. The water flow rate and silver concentration are shown in Figure 3.

Although the silver concentration was very high during the suspension as in Example 1, even when the water flow was restarted, the amount eluted was very small and was below the regulatory value.

Example 3 Specific surface area 1500? The phenolic activated carbon fiber felt of y1'/ was immersed in a silver nitrate solution, and then NaCl was added to obtain a 3.0nfit% trowel-added activated carbon fiber (he) with Afct as metallic silver. Further, in the same manner as in (b) of Comparative Example 1, 3. silver chloride was used as metallic silver. Qwt% silver-impregnated granular charcoal (T) was obtained.

A cartridge similar to that in Example 1 was made using silver-coated charcoal (a), (b), (f), and (g), and water with different salt accumulation ion concentrations in the tap water was passed through it, and while it was stopped. The silver concentration and number of bacteria were measured.

The results are shown in Table 2.

2nd Table 1 '600' Gf coal @A
yllo' 40 '1300 1/
/', 1000 activated carbon fiber e9.
AtcI j140 1 50'/7
11000 Granular Charcoal (o) Agg
O'30' 3000〃1000
1fi &'()) AfCI 20 1000
0(13) The cartridges using activated carbon fibers (a) and (f) achieved the desired effect, but the cartridges using granular carbon (b) and (g) had no effect.

[Brief explanation of drawings]

1 and 2 are longitudinal sectional side views showing an example of a water purifier according to the present invention. FIG. 3 is a graph showing the silver concentration in water flowing through the water purifier according to the present invention. Patent applicant: Kuraray Chemical Co., Ltd. Representative Patent attorney: Ken Honda (14)

Claims (1)

[Scope of Claims] 1. A sterile water purifier, characterized in that granular activated carbon is arranged in the main flow area of water, and activated carbon fibers impregnated with silver are arranged in the side flow area of water. 2. In the invention described in claim 1, the activated carbon fibers having a specific surface area of 1500"/f or more contain 0.5 to 0.5 to 100% silver as silver.
A water purifier using silver-impregnated activated carbon fibers impregnated with a water-soluble silver compound. 3. In the invention described in claims 1 and 2, the central axis area of the container is filled with granular activated carbon as a main water flow area, and the outer peripheral area of the central axis area is used as a secondary water flow retreat area. A water purifier filled with silver-impregnated activated carbon fibers. 4. In the invention described in claims 1 and 2, the central axis area of the container is filled with silver-impregnated activated carbon fibers as a secondary water flow retreat area, and the outer peripheral area of the central axis area is used as a main water flow area. A water purifier filled with granular activated carbon (1) as a flow area.