JPS61278392A - Method for improving water quality - Google Patents

Abstract

PURPOSE:To eliminate the elution of iron components and to remove ammonia, amines and free chlorine by depositing a stabilized ferrous ion composition on a porous body and bringing the obtained material covered with a waterproof moisture-permeable film into contact with water. CONSTITUTION:A composition contg. active and stabilized ferrous ions (e.g., a combination of ferrous sulfate and ascorbic acid) is deposited on a porous body 1 such as activated carbon or the body is impregnated with the composition. The porous bodies 1 are held in a waterproof moisture-permeable film 2 consisting of a hydrophobic porous film of fluorinated polyolefin, etc. The obtained bag-shaped material 3 which is liquidtightly sealed is immersed in water to be treated or brought into contact with the water. Consequently, the elution of iron components is eliminated, ammonia, amines, mercaptans, free chlorine and other contaminants can be adsorbed and removed. Moreover, the proliferation of bacteria can be prevented.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for improving the quality of drinking water, swimming pools, fish tanks, etc., and achieves the purpose with simple means without adverse effects due to side effects. This paper relates to a method for improving water quality.

(Prior Art) It is known that compounds containing divalent iron ions increase the oxygen solubility of coexisting water and have the effect of preventing water spoilage (Japanese Patent Application Laid-Open No. 135012/1983).

However, divalent iron ions are easily oxidized and unstable, which has been a problem in practical use. However, recent research has revealed that it is possible to increase the activity and stabilize it by adding an appropriate reducing agent to the iron(II) compound in an amount of 3 to 10% (Japanese Unexamined Patent Publication No. 58-15
6539).

Composition 1 containing active and stabilized divalent iron ions, for example, a ferrous sulfate/ascorbic acid aqueous solution, is supported on a porous body such as paper, fiber, activated carbon eolide, silica gel, sponge, etc. It has been recognized that the impregnated and dried product selectively adsorbs ammonia, methyl mercaptan, trimethylamine, hydrogen sulfide, etc., and functions as a deodorizing agent or an air purifying agent (Japanese Patent Application Laid-Open No. 132,937/1983).

(Problems to be Solved by the Invention) Although it has been found that compositions containing divalent iron ions are effective in removing various substances in the atmosphere by adsorption or reaction, as described in Kitagi, the effect in water is , for example, the effects on trace substances inside and the effects on water are not well understood.
The only examples in which compositions containing divalent iron ions have been used as water treatment agents are those that utilize the aggregation effect of polluting organic matter such as industrial wastewater and urban sewage, and the effect of increasing dissolved oxygen. No. 3849).

On the other hand, it goes without saying that the chemicals used in conventional household deodorizers cannot be used directly in drinking water. This is because the active substance elutes into the treated water and contaminates the water, adversely affecting the human body and imparting odor and taste.

The present inventors investigated the effect of a composition containing divalent iron ions on ammonia and amines dissolved in water, and found that the compositions reacted with ammonia and amines.

It was recognized that it has the effect of lowering the content.

Ammonia and amines are generated from human excrement such as sweat and urine, fish excrement, and uningested portions of fish food, and are dissolved in water. For example, if the water in a fish tank is not refreshed, the quality of ice will deteriorate rapidly. Well, fish farming 1! The cause of this is said to be the accumulation of ammonia and amines as well as a decrease in dissolved oxygen. It was discovered that in addition to the removal function of

Free chlorine is contained in tap water at a concentration of about 0.5 to 1 ppm, and this makes tap water taste bad! Chlorine release is added for the purpose of sterilization, and when it is removed by conventionally known methods such as activated carbon adsorption, the sterilization effect is also lost.
Treated water has poor storability. In the case of a composition containing stabilized divalent iron ions, it itself has an antibacterial effect, so if it is allowed to coexist, the treated water will have good storage properties.

However, since the active ingredients of the stabilized divalent iron ion composition are water-soluble, they will be eluted when brought into contact with water.

In particular, the elution of iron ions makes the water taste bad,
It gets worse if you add tea.

Free chlorine is 0.0% as a condition for delicious water. It is said that the iron content is 1 ppm or less and the iron content is 0.2 ppm or less, but even if chlorine is reduced, the iron content will increase.

(Means for solving the problem) As a result of intensive research, the inventors found that by supporting or impregnating the stable iron ion composition on a porous body, covering the porous body with a waterproof and moisture-permeable film, and bringing it into contact with water. It was discovered that ammonia, amines and free chlorine can be removed without elution of iron, and the present invention was completed based on this knowledge.・In other words, the present invention provides a bag-like article in which a porous body supported or impregnated with a composition containing active and stabilized divalent iron ions is held within a waterproof and moisture-permeable film and sealed fluid-tightly. The present invention provides a wood modification method characterized by immersion in or contact with water to be treated.

The waterproof and moisture-permeable film used in the present invention is a film that does not permeate wood-loving liquids such as water and aqueous liquids, but permeates air, water vapor, and other gases. Mainly microporous films of hydrophobic substances such as fluorinated polyolefins and polyolefins, or papers that do not impair their gas permeability.
It is a film with a reinforced backing made of non-woven fabric, etc.

Examples include product names, Loufilm (Mitsui Toatsu), N
Examples include those commercially available as FR Sheet (Tokuyama Teitatsu), Cellboa (Shimizu Chemical), Voatex (Junkosha), Type, Ri (DuPont), and Duragard (Polyplastics).

In the present invention, when a porous body supported or impregnated with a composition covered with a waterproof and moisture-permeable film is brought into contact with water, ammonia, amines, and While free chlorine is adsorbed and removed, iron is prevented from leaching into water.

The active and stabilized 2 used in the present invention
Examples of compositions containing valence iron ions include those disclosed in Japanese Patent Application Laid-Open No. 1986-
There are those described in JP-A No. 132937 and JP-A-60-66753. This will be explained in detail below.

The composition containing divalent iron ions used in the present invention is, for example, a combination of an iron (n) compound and ascorbic acid and/or citric acid. The iron used in this composition (
Examples of r[) compounds include ferrous sulfate, ferrous chloride,
Iron (n) such as ferrous nitrate, ferrous bromide, and ferrous iodide
In addition to inorganic salts, iron (TI) organic salts such as ferrous gallate, ferrous malate, and ferrous fumarate can be mentioned. Iron (I
I) Compounds are not limited to those exemplified above,
Any material can be used as long as it dissolves in water and forms divalent iron ions.

Ascorbic acid, L-7scorbic acid, D
- Isoascorbic # (erythorbic acid) is used, but L-7 scorbic acid is preferred.

The ratio of compound (II) to ascorbic acid and/or citric acid in the composition containing divalent iron ions is l:
The range of 0.02 to 0.3 (weight ratio) is preferable, and the range of l:o, 03 to 0.1 is more preferable.

In the present invention, the porous body supported or impregnated with the composition containing stabilized divalent iron ions is preferably a granular or plate-like body 6 For example, paper, fiber molded body, woven fabric, ceramic porous body, wood, granular activated carbon , granular zeolite, porous plastic material, sponge, and composites thereof can be used, but those supported on or impregnated with activated carbon tend to have a relatively high rate of adsorption and removal of ammonia and amines.

The amount of the composition containing divalent iron ions impregnated into the porous body is not particularly limited, and is preferably up to 30% by weight per porous body, but it may be impregnated with more than this amount if necessary.

The shape of the porous body supported or impregnated with the composition containing divalent iron ions and covered with a waterproof and moisture permeable film is preferably relatively simple and has a large contact area with water. Therefore, a bag-like product obtained by sandwiching a porous body between two waterproof and moisture-permeable films and sealing the four sides in a fluid-tight manner is convenient for manufacturing and practical use.

An example of this bag-like material is shown in FIG.

In addition, a porous body supported or impregnated with the composition containing divalent iron ions is stored in a waterproof and moisture permeable film bag,
The storage opening may be sealed fluid-tightly.

(Effects of the Invention) According to the present invention, it is possible to treat tap water and remove free chlorine therein, thereby producing good water.

It can also be applied to pool water or fish tank wood to adsorb and remove ammonia amines, mercaptans and other pollutants derived from human excreta such as sweat and urine and excreta from cultured fish. Therefore, it is possible to purify water and significantly increase the survival rate of cultured fish and ornamental fish. Furthermore, according to this method, since the composition containing divalent iron ions exhibits bacteriostatic action, the proliferation of bacteria can be prevented and the water can be used for a long time.

In the present invention, one bag-like product can be used by placing it near the wall below the water surface of a pool or fish tank, or placing it in a tea pack in a water bottle in a refrigerator. Another feature of the present invention is that it can be easily updated after a certain period of use.

(Example) The present invention will be described below with reference to Examples, but the present invention is not limited thereto.

Example 1 25.7 g of ferrous sulfate heptahydrate (molecular weight 278.03) was dissolved in ion exchange water to create a roomM solution.

0.5 g of L-7 scorbic acid was added and dissolved in this solution to obtain an aqueous solution containing active and stabilized divalent iron ions. .

Activated carbon was impregnated into the above aqueous solution, taken up and dried to obtain supported activated carbon having a weight increase of 15%. Next, as shown in Fig. 1, the above-mentioned supported activated carbon (1) Ig was placed in a 2 cm x 4 cm bag (3) made by using hot melt adhesive on the edges 2a of two W films (2). The storage opening was also sealed using hot melt adhesive.

500cc of tap water in each 500cc glass beaker
Dip the bag into one of the bags, leave it at room temperature, and measure the amount of free chlorine over time.

The amount of dissolved iron was measured. The measurement method and results are shown below.

Amount of free chlorine: iron amount determined by residual chlorine measuring device (0-) lysine method (manufactured by Shibata Chemical Co., Ltd.); 1.5 mJL of 6NHCR and sample water were put into a 20mM volumetric flask to make a constant volume, and subjected to atomic absorption spectrometry.

From the results in the table above, it can be seen that free chlorine in the water that came into contact with the bag rapidly decreased, and no iron content was leached.

Example 2 Polyethylene container with lid (for barley tea refrigeration, IJI) 4
Two of the bags were filled with tap water, the same bags as those produced in Example 1 were placed in two of the bags, and after being allowed to stand for 5 hours, the water was subjected to a sensory test by 10 tasters. As a result, 9 out of 10 people reported that the water with a bag in it tasted better, and 1 person reported that there was no difference. 7 people said the reason why the water with 0 bags in it tastes better. 5 people cited the lack of a chlorine odor and the lack of a plastic odor.

Example 3 40 parts of clay and 40 parts of wood were added to 60 parts of the same supported activated carbon obtained in Example 1, kneaded, pressed and dried to give 8 c.
A mX4cmXO, 8cm (7) molded plate (2-9g) was obtained. This molded plate was sandwiched between two pot films, and the four sides were sealed using a hot melt adhesive to obtain a board-like product.

Two 5Jl aquariums without an air blowing device were each filled with tap water that had been stored in an open container for one day to remove chlorine.
The above-mentioned board-like material was immersed in one of the two, and 10 goldfish were placed in each.5 A breeding experiment was conducted by simply replenishing the evaporated water without renewing the water. In the case where the board-like material was not introduced, the water became dirty after one week and two animals died, so the experiment was discontinued. The aquarium into which the board-like material was placed did not emit any bad odor for three months, and there were no deaths.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a bag filled with activated carbon carrying a composition containing divalent iron ions used in the present invention. Patent applicant: Director of the Agency of Industrial Science and Technology, etc., Minato Sangyo Co., Ltd., Jo/7

Claims (1)

[Claims] 1. A bag-shaped bag formed by holding a porous body supported or impregnated with a composition containing active and stabilized divalent iron ions in a waterproof and moisture-permeable film and sealing the same in a fluid-tight manner. A water quality reforming method characterized by immersing or bringing objects into contact with water to be treated. 2. The water quality reforming method according to claim 1, wherein at least a part of the porous body contains activated carbon.