WO2016024408A1

WO2016024408A1 - Iron supplying member for environmental water, iron supplying member maintenance method and method for supplying iron to environmental water

Info

Publication number: WO2016024408A1
Application number: PCT/JP2015/004054
Authority: WO
Inventors: 小島　昭; 昌生藤重; 敏明石井
Original assignee: 石井商事株式会社; 独立行政法人国立高等専門学校機構
Priority date: 2014-08-14
Filing date: 2015-08-14
Publication date: 2016-02-18
Also published as: JPWO2016024408A1

Abstract

The present invention comprises an iron member, a carbon member and a conduction member, wherein the iron member and the carbon member are arranged without constraining each other; the conduction member has a volume resistivity of 10^-4 Ω·m or less; and the conduction member connects the iron member and the carbon member and continually keeps the carbon member and the iron member in a good state of contact, thereby allowing iron to be efficiently supplied to environmental water.

Description

Iron supply material to environmental water, maintenance method of iron supply material, and iron supply method to environmental water

The present invention relates to an iron supply material to environmental water that can always maintain a good contact state between a carbon material and an iron material, a maintenance method thereof, and an iron supply method to environmental water using the same.

There is a word "forest is a lover of the sea". This is a word that expresses the fact that the sea is activated by the iron flowing from the forest. However, the actual Japanese sea has the sixth largest sea area in the world, but it has been burned in anemia, making it difficult to produce kombu, and seafood. These factors vary, but the lack of iron flowing from the forest is one of them.

On the other hand, there are areas on the earth where plants do not grow in the sea. Although the sea area is rich in nitrogen and phosphorus, phytoplankton does not increase and chlorophyll concentration tends to be low. This is due to the lack of iron in micronutrients.
Therefore, supplying iron can increase the plant plank, grow shrimp, oysters and shellfish that feed on it, and also make it possible to breed kombu and seaweed.

And various things are proposed as an iron melt | dissolution technique to seawater.
They are loaded with iron sulfate for drug administration. However, this is also limited and continuous administration is difficult.
There is also a technology for throwing a disposable body warmer solidified with water or the like into the sea as a charcoal dumpling or a charcoal dumpling. However, iron turns into iron oxide and has little effect, and iron and charcoal are in point contact, and the reaction is deactivated instantly.
There is also a technique for melting iron by embedding steel slag in seawater. Slag itself is an industrial waste and may contain harmful heavy metals, and there are many problems.

As described above, no method has been proposed for supplying safe iron ions in seawater continuously and at an arbitrary concentration other than a method for introducing a drug.
Furthermore, supplying high-concentration iron ions can be achieved by applying voltage to the carbon material and the iron material to perform electrolysis, but considering the power supply equipment and the work to maintain it, it can be supplied over a long period of time. Not suitable for.

Further, Patent Document 1 discloses a water reforming apparatus that adds a predetermined function to water by being placed in a water pipe or a water tank or the like in a state of being submerged in water. Corrosion of the higher-potential metal plate 42 having a smaller ionization tendency among the two different-type metal plates is made by providing the two different types of different metals 41 and 42 in a state of being in close contact with each other. The lower potential of the higher potential of ionization due to the sacrificial corrosion action of the lower potential of the metal plate 41 that moves electrons from the lower potential metal plate 41 to the higher metal plate 42 to prevent. A technique is described in which metal ions are permanently eluted from the metal plate 41 and the functions of the metal ions are applied to water and / or water piping, water storage tanks and the like in contact with the water.
This technique is described as “a configuration in which two different kinds of different metals having different ionization tendencies (potentials) are provided in close contact with each other”, and it is necessary that the different kinds of metals are in close contact.

Furthermore, in Patent Document 2, as provision of a water treatment tool capable of sustaining efficient elution of metal ions over a long period of time, a predetermined water treatment is performed by metal ions eluted by immersing in water to be treated. It is a water treatment tool to be performed, and a metal sheet containing carbon and a metal plate having a lower potential (high ionization tendency) than carbon one by one, or in a state where a plurality of sheets are alternately stacked so that the metal becomes an outer surface And a fiber sheet containing carbon on both end faces by being pressed and rolled into a stacking direction by pressing or rolling so that the fiber sheet containing carbon and the metal plate are kept in close contact with each other. The structure by which the contact boundary part with a metal plate is exposed and formed in the state which contacts water is disclosed. This technology is also said to have a structure in which the steel sheet is pressed or rolled in the stacking direction so that the fiber sheet containing carbon and the metal plate are kept in close contact with each other. Is essential.

On the other hand, in Patent Document 3, a metal ion water production method or water treatment method and metal ion water production tool or water treatment apparatus capable of efficiently performing water treatment for various treatments at low cost. Is disclosed.
That is, a local battery is formed by immersing a water treatment apparatus having a structure in which two kinds of metals having different ionization tendencies are in close contact with each other in water to be treated, and metal ions eluted from a metal having a large ionization tendency It is said that water treatment (sterilization, algae killing) is performed.
This technique is also “a water treatment apparatus having a structure in which two types of metals having different ionization tendencies are in close contact with each other” and is a direct contact type of two types of metals.

Further, in Patent Document 4, it is important to remove phosphorus in water or to make it insoluble in water in order to prevent the occurrence of aquatic or acacio by phosphorus, and this is insoluble in water by chemical reaction with phosphorus. Flocculants (iron compounds, aluminum compounds, etc.) that make phosphorus compounds are required, but the anion component added at the same time accelerates environmental pollution. To solve this point, only iron is put into water. It is described that a method of supplying was found.
It provides a phosphorus removal apparatus and a phosphorus removal method that can quickly remove phosphorus in water without adding unnecessary ions and components therein.

Patent Document 5 is an apparatus for removing phosphorus dissolved in water to be treated containing phosphorus and selected from the group consisting of magnesium, aluminum, zinc and iron. An anode member made of one or more metals and a high standard electrode potential material having a higher standard electrode potential than the metal, or a cathode member made of a carbon material having electrical conductivity, and at least A phosphorus removal apparatus is disclosed, wherein a part of the anode member and a part of the cathode member are in contact with each other. Also disclosed is a phosphorus removal method in which a part of an anode member and a part of a cathode member are brought into contact with each other in water to be treated to precipitate a phosphorus compound.

JP 2006-116527 A JP 2006-88085 A WO2005019116 A1 Japanese Patent No. 4556038 Japanese Patent No. 5540434

However, even with the technique described in the above-mentioned patent document, the following problems still remain.
(1) When processing a high concentration and a large amount of wastewater such as factory wastewater and livestock wastewater in a short time, it cannot be applied because the amount of dissolved iron is small.
(2) The carbon material and the iron material must always be in contact with each other. Although it is possible to maintain this state immediately after the start of purification, since the iron material is dissolved, a space and a gap are formed between them, and the dissolution rate of iron is reduced.
(3) Iron oxide and iron phosphate are generated by dissolution of iron. These substances are insulators, and when they are present at the contact point between the carbon material and the iron material, the dissolution rate of iron decreases. It needs to be removed quickly and requires water flow, aeration, agitation, vibration and the like.
(4) The carbon material needs to have high electrical conductivity. The optimal carbon material is a graphite material, but it cannot be used from an economic viewpoint. The carbon fiber is preferably graphitized carbon fiber, but is difficult to use from the viewpoint of cost. Carbon fiber is an artificial material and cannot be decomposed in nature. Therefore, it is indispensable to collect, but it is often difficult with environmental water.
(5) It is impossible to recover iron phosphate and iron oxide generated from iron. In ponds that emphasize landscapes, red matter is not allowed to be generated and deposited on the bottom of the pond.
(6) When there is a flow in the installed environmental water, the product is easily removed, but in the case of static water, it exists at the interface between iron and charcoal and inhibits the reaction.
(7) Since a large amount of iron and carbon materials must be used to generate high-concentration iron ions, the apparatus becomes large and costs increase.

In addition, the inventors have heretofore carried out direct adhesion between a carbon material and an iron material in order to generate iron ions that remove phosphorus in water. However, it could not be processed in the following cases. The present invention has solved such problems. The problems so far are listed.
(1) Since iron melt | dissolved, the adhesiveness fell and the production | generation condition of iron ion fell.
(2) The iron oxide produced | generated in the contact part of a carbon material and an iron material precipitated, and the production | generation condition of the iron ion was reduced.
(3) The landscape of environmental water was damaged by red precipitates.
(4) When wastewater containing high-concentration phosphorus is treated in a large amount in a short time, the amount of iron produced is insufficient.
(5) When processing a high concentration phosphorus containing wastewater in a short time, the amount of iron to produce was insufficient.
(6) When a large amount of low-concentration phosphorus-containing wastewater is treated in a short time, the amount of iron produced is insufficient.

Furthermore, when direct contact is made such that a steel bar and a charcoal bar are bound with a rubber band, there are the following problems as actual problems.
(1) Contact failure due to precipitates generated at the interface (2) Contact failure due to dissolution of iron material In addition, when carbon elution is performed for a long time with a carbon fiber fabric, iron plate, and iron bar, the performance is low. The phenomenon of becoming has been recognized. This is also for the same reason.

Describing the above phenomenon as a specific example, in order to suppress the occurrence of water pups in a certain pond, one piece of iron net (45 cm × 45 cm) was inserted into a bag (50 cm × 50 cm) made of carbon fiber fabric. During the two months of installation, phosphorus in the pond water was removed, and no water was generated. However, phosphorus began to be detected in the water three months after the installation.

However, the iron material in the carbon fiber fabric was not completely dissolved, and most of it remained. Then, when we pulled out the iron net from the carbon fiber fabric, a large amount of red matter was attached. Moreover, the peeled red thing was storing in the lower part of the carbon fiber bag. From such a situation, it is considered that the contact between iron and carbon fibers is hindered by the red material, the dissolution of iron is stopped, and the decrease in the phosphorus concentration in water disappears. The red matter adhered to the iron net and the red matter stored at the bottom of the carbon fiber fabric were oxides formed by oxidation of iron or iron phosphate.

In another experiment, we wrap a carbon fiber fabric around an iron pipe (diameter: 6 cm, length: 50 cm) and fix it with a binding band from its upper surface. Used for wastewater purification.
During the first week of the experiment, the phosphorus concentration in the livestock effluent decreased, but thereafter the decrease in the total phosphorus concentration decreased. That is, wastewater purification could not be performed. Therefore, the carbon fiber fabric wound around the iron pipe was peeled off and the surface of the iron pipe was observed. On the surface of the iron pipe, a red object adhered to the surface of the iron pipe, and the contact between the iron and the carbon fiber fabric was obstructed.

The present invention has been developed in view of the above-described situation, and a maintenance method for an iron supply material to environmental water that can always maintain a good contact state between a carbon material and an iron material, and an environment using the same. It aims at providing with the iron supply method to water.
That is, in the present invention, the carbon material and the iron material are not brought into close contact with each other, but are brought into contact with each other through a conducting wire, or the carbon material having a large surface area is brought into contact with each other through the iron material and the conducting wire. The above-mentioned problems were successfully eliminated by a method in which the carbon material was brought into contact with each other via a conductive wire.

In order to solve the above problems, the inventors repeated trials and created an indirect contact type iron melting material in which an iron material and a carbon material are brought into contact with each other through a lead wire.
Instead of making direct contact between the iron material and the carbon material, we examined whether it is possible to make contact through a conductor having electrical conductivity.

First, seawater was put into a beaker, and a carbon bar and a steel bar were separated from each other, and each end was connected by a single wire fixed with an alligator clip. One day later, there was a reddish brown precipitate at the bottom of the beaker. This indicates that the iron has dissolved. Since the carbon material and the iron material are connected by a conductive wire, it was confirmed that the iron can be dissolved without direct contact.

Next, when it was tried not with seawater but with fresh environmental water, dissolution of iron was observed. In this case, the amount of iron dissolved was less than that of seawater.
Assuming that there is water movement such as river flow and wave effects, it was found that the amount of iron dissolved increased when the contents of the beaker were stirred with a stirrer.
Furthermore, using the pond water in the zoo's monkey breeding house, we examined whether there was a phosphorus removal action by iron. Due to the dissolution of iron, the phosphorus concentration in the water was below the detection limit.

In order to remove the phosphorus component dissolved in water, the phenomenon described above is caused by indirect contact between a carbon material and an iron material in water to generate iron ions, which react with phosphate ions, resulting in insoluble phosphorus. It is explained by making it into a compound. In addition, the iron ions supplied into the water are generated by generating a chemical cell by indirectly contacting the carbon material and the iron material in the water, generating an electromotive force.

Furthermore, the magnitude of the electromotive force can be determined by measuring the voltage and current. If the electromotive force is large, the generated current is large and the amount of iron dissolved is large. The electromotive force varies depending on the surface area of the iron material and carbon material used. In order to increase the amount of iron dissolved, it is necessary to make the surface area of the carbon material larger than that of the iron material. In addition, when evaluating the performance of activated carbon normally, it represents with a specific surface area, However, The surface area in this invention is the surface area calculated | required from the magnitude | size of the external shape to the last, and is an apparent surface area.

And the following things became clear from various experimental results including the examples shown below.
(1) Although iron can be dissolved alone, the dissolution rate of iron is increased by contact with a carbon material or connection with a conductive wire.
(2) The dissolution rate of iron was larger in the stirring and mixing state than in the stationary state.
(3) By connecting carbon and iron with a conducting wire, the iron dissolution rate was increased.
(4) The amount of iron dissolved was increased by using a plurality of irons for one carbon material.
(5) By connecting one iron bar and a plurality of carbon materials, the dissolution rate of iron became large.
(6) Increasing the surface area of the carbon material increased the dissolution rate of iron.
(7) When a large amount of iron is dissolved in a short time, it is effective to use a carbon material having a large surface area. Furthermore, in order to increase the amount of iron dissolved, it is effective to increase the surface area of the iron material.
The inventors have further studied based on the above-described findings and completed the present invention.

That is, the gist configuration of the present invention is as follows.
1. An iron material, a carbon material, and a conductive material, wherein the iron material and the carbon material are arranged without being bound to each other, and the volume resistivity of the conductive material is 10 ⁻⁴ Ω · m or less, and the conductive material Is an iron supply material to the environmental water connecting the iron material and the carbon material.

2. 2. The iron supply material to environmental water as described in 1 above, wherein the volume resistivity of the conducting material is 10 ⁻⁷ Ω · m or less.

3. The iron supply material for environmental water according to 1 or 2, wherein the conductive material is made of metal or carbon fiber is covered with an insulating material.

4). 4. The iron supply material to environmental water according to any one of 1 to 3, wherein the iron material is an iron material having a purity of 90% or more.

5. 5. The iron supply material to environmental water according to any one of 1 to 4, wherein the iron material is at least one selected from a plate, a rod, a net, a cylinder, a sheet, or a lump.

6). 6. The iron supply material for environmental water according to any one of 1 to 5, wherein the carbon material has a volume resistivity of 10 ⁰ Ω · m or less, preferably 10 ⁻⁴ Ω · m or less.

7). 7. The iron supply material for environmental water according to any one of 1 to 6, wherein the carbon material is plate-shaped.

8). 8. The iron supply material to environmental water according to any one of 1 to 7, wherein two or more carbon materials are connected to the iron material by a conductive material.

9. 9. The iron supply material to environmental water according to any one of 1 to 8, wherein two or more iron materials are connected to the carbon material by a conductive material.

10. 10. The iron supply material to environmental water according to any one of 1 to 9, wherein the iron supply material to the environmental water is further in contact with at least a part of the iron material.

11. The iron supply material to the environmental water as described in 10 above, wherein the humus is disposed on the outer periphery of the iron material.

12 The iron supply material to the environmental water according to 10 or 11 above, which is wrapped with a self-shrinking binding material from the outside of the humus.

13. The environmental water that causes the iron supply material to be supplied to the environmental water according to any one of the above 1 to 9 to be installed in at least one environmental water selected from among rivers, lakes, and seas, and to elute iron into the environmental water Iron supply method

14 The iron supply material for environmental water described in any one of 10 to 12 above is installed in at least one environmental water selected from among rivers, lakes and seas, and iron is eluted into the environmental water as an iron complex. To supply iron to environmental water.

15. The method for supplying iron to the environmental water according to the above 13 or 14, wherein the surface area of the carbon material and / or the iron material in the environmental water is adjusted, and the elution amount of iron as an iron content or iron complex is adjusted. .

16. A maintenance method for an iron supply material to environmental water, in which only the iron material is taken out and replaced from the iron supply material to the environmental water described in any one of 1 to 12 above.

17. 13. A method for maintaining an iron supply material to environmental water by measuring the amount of conduction of the conducting material of the iron supply material to the environmental water according to any one of 1 to 12 above, and determining a replacement time of the iron material.

Since the iron supply material according to the present invention can arbitrarily control the amount of iron dissolved, it is possible to effectively supply iron and iron complexes to the environmental water.

It is a figure which shows an example of the iron content supply material to the environmental water of this invention. It is a figure which shows an example of the structure which two or more carbon materials are connected with the electrically conductive material with respect to the iron material. It is a figure which shows an example of the structure to which the iron material is connected with the carbon material by 2 or more with the electroconductive material. It is a figure which shows an example which made the iron content supply material to the environmental water of this invention the communication pipe type. It is a figure which shows an example which has arrange | positioned humus soil further to the iron content supply material to the environmental water of this invention. It is a figure which shows another example which has arrange | positioned humus soil further to the iron supply material to the environmental water of this invention. It is a figure which shows an example of the collection | recovery container of the red product in the iron supply material to the environmental water of this invention. It is a photograph which shows the carbon plate and iron plate, carbon rod, and iron rod which were used for the Example of this invention. It is another photograph which shows the carbon plate and iron plate, carbon rod, and iron rod which were used for the Example of this invention.

Hereinafter, the present invention will be specifically described.
As shown in FIG. 1, the iron supply material to the environmental water of the present invention comprises an iron material, a carbon material, and a conductive material, and the iron material and the carbon material are arranged without being bound to each other, that is, separated from each other. ing. The iron material and the carbon material are connected (indirectly contacted) by a conductive material having a volume resistivity of 10 ⁻⁴ Ω · m or less, preferably 10 ⁻⁷ Ω · m or less.

The conductive material is not particularly limited as long as the volume resistivity is 10 ⁻⁴ Ω · m or less, but it needs to be able to withstand use in an environment with environmental water. Specific examples include lead wires, electric wires, enamel wires, vinyl wires, cable wires, tin-plated wires, etc., which have a configuration in which a conductive material such as metal or carbon fiber is covered with an insulating material. is there. It is preferable to set the volume resistivity of the conductive material to 10 ⁻⁷ Ω · m or less because sensitivity at the time of current measurement described below is increased and life (replacement time limit) can be managed more accurately.

A connector can be used when connecting a conducting wire from a plurality of carbon materials (or iron materials) and one iron material (or carbon material). Carbon fiber can also be used.
When not used in water, the metal may be exposed. However, when used in a natural environment exposed to wind and rain, particularly underwater or in the sea, it is necessary to be covered with an insulating material.

The iron material is basically free of harmful impurities. As a specific example, an iron material having a purity of 99% or more is preferable. However, the country defines a component having a purity of 90% or more and high biotoxicity determined by the country. Any iron material that does not contain more than the standard may be used. In addition, depending on a use, what contains iron content partially can also be used, In this case, the elution part of an iron ion may be called an iron material.

The shape of the iron material is appropriately selected according to the installation environment, but is preferably at least one selected from a plate, a bar, a net, a cylinder, a sheet, a lump, and the like.

The carbon material is preferably one that has high electrical conductivity, low electrical specific resistance, high mechanical strength, and is not easily broken. Specifically, there are graphite for crucible, graphite material, electrode material, carbon material for motor brush, charcoal, bamboo charcoal and the like. Further, in order to increase the durability and strength of the graphite material, it can be protected by covering the outer periphery with a net or mesh.

Furthermore, in the present invention, since there is no direct contact with the iron material, a high conductivity and high quality graphite material can be selected, and its electrical conductivity is 10 ⁰ Ω · m or less in volume resistivity, preferably 10 ⁻⁴ Ω. -It is preferable that it is m or less. In addition, depending on a use, what partially contains carbon can also be used, and in this case, the part containing carbon may be called a carbon material.

In the present invention, since the carbon material and the iron material do not bind each other, the shape of the carbon material is not particularly limited, but is preferably a plate shape. In the present invention, it is important that the iron material and the carbon material are not constantly in direct contact (restrained) in the environmental water, and the carbon material and the iron material are inadvertently in contact with each other by a water flow or the like. There is no problem.

In the present invention, as shown in FIG. 2, it is possible to adopt a configuration in which two (two) or more carbon materials are connected by a conductive material to an iron material.

The above configuration is particularly effective for the treatment of industrial wastewater containing a large amount and high concentration of phosphorus. In the treatment of industrial wastewater containing a large amount of phosphorus and a high concentration, a large amount of iron ions is required. By using multiple iron materials for one carbon material, a large amount of iron ions can be generated and processed. Become.

Moreover, in this invention, as shown in FIG. 3, the structure which the iron material has connected with the carbon material by 2 or more can be taken.
This is because by adopting this configuration, it becomes possible to supply stable iron in a wide range.

In addition, even in the case of running water such as rivers, purification can be achieved by installing a number of purification units that connect multiple iron materials to one carbon material, and one iron material and multiple carbon materials, from upstream to downstream. Processing is possible.
In addition, oysters and shellfish farms under seawater flow require high-concentration iron supply, but one carbon material and several iron materials, one iron material and several iron materials on the squid. By connecting carbon materials, high concentration iron can be supplied.

When the iron supply material of the present invention is used to proliferate seaweed and aquatic plants, a carbon material and a plurality of iron materials are connected, that is, an iron supply in which one carbon material and a plurality of iron materials are connected by lead wires. Create a unit and float it on the surface of the water. And the iron supply material of this invention can be used in order to proliferate seaweed and aquatic plants by hold | maintaining the lower part of an iron dissolution apparatus in water and the upper part on water.
In addition, as a structure of this invention, as shown in FIG. 4, it is good also as a communication pipe type.

Furthermore, the iron supply material of the present invention is effective for use in lakes and the like having a large area. It is a combination of one carbon material and a plurality of iron materials, covering a wide area, especially in places where a large amount of iron ions are required, using one iron material and a plurality of carbon materials. This is because the environmental water can be efficiently purified.

Here, the connection between the iron material and the conductive material, and the carbon material and the conductive material is performed by using a method of sandwiching with a crocodile clip, a clamp, an edge, etc., using a conductive adhesive (or paste, tape, sheet, paint, etc.). Such as a method of bonding, a method of fixing with a bolt via a metal plate on both sides of a carbon material, a method of drilling a hole in the upper surface or side surface of a carbon material, and inserting (screwing) a metal rod into the conductive material, A publicly known connection method and means for connecting the electrodes can be used.

Also, among the above methods, for example, a method used for a carbon brush can be cited as a suitable example for the connection between the carbon material and the conductive material. It is also possible to insert it into a connecting jig (a jig having an insertion hole) made of the same material as the conducting wire. When there is a possibility that local battery action will occur at the connection point with the iron material, such as when carbon fiber is used as the conductive material, a connection method that does not cause local battery action at the connection point with the iron material should be adopted. Is required. This is because the connection location may be lost.

In addition, in the present invention, as shown in FIGS. 5 and 6, the above-described iron supply material to the environmental water can be configured such that humus is in contact with at least a part of the iron material, and the arrangement thereof It is preferable to arrange humus on the outer periphery of the iron material.

Furthermore, in the present invention, in order to effectively elute the iron complex, as shown in FIGS. 5 and 6, the iron material and the carbon material may be a basic configuration of the iron supply material, and humus may be disposed on the outer periphery of the iron material. preferable.

The humus in the present invention is not particularly limited as long as it is a known humus, but specifically, organic matter produced by the above-ground plants in the forest ecosystem becomes deciduous trees, deciduous leaves, and twigs, and accumulates on the surface. Because it is decomposed by biochemical metabolic action by microorganisms such as bacteria and earthworms such as earthworms (deciduous leaf decomposition) and becomes soil, strictly speaking, it is not soil, but generally Use what is called humus or humus.

Naturally humus is often biased towards nitrogen, but phosphoric acid and potassium may be supplemented by earthworms, other animal feces and microorganisms. In addition, although the humus produced artificially has the component adjusted artificially, there is no problem in the use to this invention.

Here, leaves that tend to become humus are deciduous trees and broad-leaved trees, such as deciduous trees and broad-leaved trees, that are easy to ferment, and leaves that are rich in oil such as cedar and pine are less likely to become humus.
Naturally made humus takes more than a year or two to ferment, but when it is made artificially, it uses rice bran to create an environment that is easy to ferment. Therefore, the period until completion is shortened to about two months.

As described above, the properties of humus vary depending on the raw materials and the production method, but it is important to select the most suitable humus.
Specifically, the mulch is preferably one that has thick leaf flesh such as cypress, sardine, arakashi, beech, kunugi, konara, chestnut, and deposits fallen leaves of broad-leaved trees and is appropriately fermented. The condition to be used should be fermented to the extent that it can be easily broken by hand, and the ones that use fallen leaves of the beech family such as Japanese oak and chestnut are especially best. Furthermore, what contains iron, potassium, calcium, magnesium etc. which are essential elements for the growth of seaweed as a mineral component is preferable.
In humic soil with insufficient fermentation, the content of fulvic acid is small and the effect is small. On the other hand, when it reaches a fully matured state, it becomes difficult to produce an oxygen-free state, and the effect may be reduced.

In addition, the present invention can be wrapped from the outside of the mulch with a self-shrinking lashing material. This is because, with such a configuration, the iron material and the humus can always come into contact stably. The lashing material in the present invention is preferably a mesh-shaped rubber material or a nylon net, but for example, it is simply fastened with a rubber string or tyed with a nylon thread or the like. To include.

The iron supply material according to the present invention is installed in any place (environmental water) that requires supply of iron, that is, in a river, a lake, or the sea, so that iron can be effectively converted into ions or iron complexes in environmental water. Can be eluted.

In the above-described method for supplying iron to the environmental water, the surface area and number of carbon materials and / or iron materials in the environmental water are adjusted, and the elution amount of iron as iron or iron complex is adjusted.

In the present invention, since the iron material and the carbon material are not in direct contact, it is possible to take out and replace only the iron material from the iron supply material to the environmental water.
Moreover, recovery of iron oxide and iron hydroxide produced by dissolving iron has not been easy. This is because the iron supply material is plate-like and bulky, and it is difficult to install the collection container. However, in the iron supply material in the present invention, since the carbon material and the iron material are separately arranged, the product from the iron material is only the lower part of the iron material, and the lower part of the iron material is covered with a cloth bag or the like. Thus, recovery can be performed easily.
Specifically, as shown in FIG. 7, by arranging a container around the iron material, the red product can be collected and the diffusion to the natural environment is prevented.

Furthermore, the iron supply material to the environmental water according to the present invention can accurately determine the replacement time of the iron material by measuring the amount of conduction of the conductive material. It is important to create a management standard beforehand, for example, when the initial energization amount is reduced to 80% or 50%. This eliminates the need to go to land many times to check the actual iron content. The energization amount may be at least one selected from current, voltage, and power.

[Example 1]
In salt water, iron and charcoal were in close contact, and iron and charcoal were contacted with a conductive material.
The two photographs shown in FIGS. 8 and 9 are the carbon plate and iron plate, carbon rod and iron rod used in the examples. There are carbon plates with and without connection terminals, and the carbon plates in FIG. 9 have metal copper terminals. In addition, when using it in actual environmental water, it is desirable that the terminal portion is also covered with an insulating film.

100 mL each of 3% -sodium chloride aqueous solution was added to two 100 mL beakers. The iron bar used in the experiment had a diameter of 2 mm and a length of about 10 cm, and the carbon bar (volume resistivity: 10 ⁻⁴ Ω · m) had a diameter of 5 mm and a length of about 10 cm. Both were set to soak in 4.5 cm in an aqueous sodium chloride solution.
In each beaker, the following experiment was conducted.
Experiment 1-1 (Comparative Example): An iron bar and a carbon bar were fixed with a rubber band, and only the lower part of about 4.4 cm was used in the solution. The aqueous sodium chloride solution was stirred with a stirrer. The rotation speed was 180 rpm.
Experiment 1-2 (Invention example): A steel bar and a carbon bar were connected with a lead wire, and only the lower part of 4.4 cm was attached to the solution. The aqueous sodium chloride solution was stirred with a stirrer. The rotation speed was 180 rpm. Moreover, the volume resistivity of the lead wire as the conductive material was 2 × 10 ⁻⁷ Ω · m.
After elapse of a predetermined time, the iron bar was taken out, washed with water and dried, and the mass was measured. At that time, the sodium chloride aqueous solution was replaced with a new aqueous solution. Table 1 shows the mass of the iron bar after a predetermined time.

When a steel bar and a carbon bar were directly contacted and the periphery thereof was fixed with a rubber band (Experiment 1-1), the dissolution rate was 0.528 mg per hour (hereinafter, the unit is described as (mg / H)). . Further, per unit area, it was 0.129 mg / H (hereinafter, the unit is described as (mg / cm ² · H)).
When both were connected by lead wires (Experiment 1-2), the dissolution rate of iron was 0.744 mg / H (0.181 mg / cm ² · H), and the dissolution rate further increased. This shows that when both were connected with lead wires, the contents of the beaker were stirred with a stirrer, so that the precipitated product was removed and good contact between iron and charcoal was maintained. Yes.

[Example 2]
In salt water, iron, iron, and charcoal were contacted with a conductive material, and the dissolution state of iron was examined when one iron was contacted with two irons with a conductive material.
A 3% aqueous sodium chloride solution was added to a 2 L beaker. The iron bar used in the experiment was 2 mm in diameter and about 10 cm in length. The carbon rod (volume resistivity: 10 ⁻⁴ Ω · m) had a diameter of 5 mm and a length of about 10 cm. Both were set to soak in 3.7 cm in an aqueous sodium chloride solution. The surface area of the iron bar immersed in sodium chloride is 0.2 cm × 3.14 × 3.7 cm = 2.3 cm ² .
Experiment 2-1 (Comparative Example): One iron bar was set up vertically in a beaker.
Experiment 2-2 (Invention Example): An iron bar and a carbon bar were each set up vertically in a beaker. The distance between the carbon bar and the iron bar was about 3.7 cm. The iron bar and the carbon bar were connected by a lead wire which is a conductive material. The length of the lead wire itself was about 34 cm. The volume resistivity of the lead wire was 2 × 10 ⁻⁷ Ω · m.
Experiment 2-3 (Invention Example): Two iron bars (iron bar 1 and iron bar 2) and one carbon bar were set up vertically in a beaker. The distance between the carbon bar and the iron bar 1 was about 3.7 cm, and the distance between the carbon bar and the iron bar 2 was 7.1 cm. The two iron bars and the carbon bar were connected by lead wires.
All salt water was stirred with a stirrer. In addition, the volume resistivity of each of the lead wires as the conductive material was 2 × 10 ⁻⁷ Ω · m.
After a predetermined time elapsed, the iron bar was pulled up, washed with pure water, dried, and then weighed.
Over time, the beaker containing the iron bar became reddish brown and became opaque due to the formation of precipitates. Table 2 shows the mass of the iron bar over time.

In Experiment 2-1, when the iron bar was immersed in salt water for 76 hours, the dissolution rate was 0.213 mg / H (0.093 mg / cm ² · H).
In Experiment 2-2, when the iron bar and carbon bar are connected with lead wires, the dissolution rate becomes 1.19 mg / H (0.517 mg / cm ² · H), and the iron bar is immersed in salt water for 76 hours alone. Increased by a factor of 5.5.
In Experiment 2-3, when two steel bars were connected to one carbon bar with two lead wires, the dissolution rates were 0.928 mg / H (0.403 mg / cm ² · H) and 0. It was 771 mg / H (0.335 mg / cm ² · H). The dissolution rate of the two iron bars combined was 1.699 mg / H (0.738 mg / cm ² · H), which was higher than when only one iron bar was used.
In order to dissolve a large amount of iron from individual iron bars, it is more effective to use a pair of iron bars and carbon bars. On the other hand, the method of connecting a plurality of iron bars to one carbon bar has the advantage of reducing the number of carbon bars used.

Example 3
When one iron was put in salt water alone, the dissolution state of iron when one charcoal was contacted with three irons with a conductive material was examined.
A 3% sodium chloride aqueous solution was added to a 1 L beaker.
The iron bar used in the experiment was 2 mm in diameter and about 10 cm in length. The carbon rod (volume resistivity: 10 ⁻⁴ Ω · m) had a diameter of 5 mm and a length of about 10 cm. Both were set to soak in 4.5 cm in an aqueous sodium chloride solution. The surface area of the iron bar immersed in the salt water is 0.2 cm × 3.14 × 4.5 cm = 2.83 cm ² .
Experiment 3-1 (Comparative Example): One iron bar was set up vertically in a beaker.
Experiment 3-2 (Invention): Three iron bars (iron bar 1, iron bar 2, and iron bar 3) and one carbon bar were set up vertically in a beaker. The distance between the carbon rod and the iron rod 1 was about 4.0 cm, the distance between the carbon rod and the iron rod 2 was 3.9 cm, and the distance between the iron rod 3 and the carbon rod was 3.9 cm.
Each iron bar and carbon bar were connected by lead wires. The brine was stirred with a stirrer. After a predetermined time had elapsed, each iron bar was pulled up, washed with pure water, dried, and then weighed.
In addition, the volume resistivity of each of the lead wires as the conductive material was 2 × 10 ⁻⁷ Ω · m.
Over time, the beaker containing the iron bar became reddish brown and became opaque due to the formation of precipitates. Table 3 shows the mass of the iron bar over time.

When the iron bar in Experiment 3-1 was immersed in salt water for 119 hours, the dissolution rate was 0.23 mg / H (0.081 mg / cm ² · H).
In Experiment 3-2, when three iron rods were connected to a carbon rod with three lead wires, the dissolution rates were 0.78 mg / H, 0.80 mg / H, and 0.81 mg / H. The dissolution rate of the three iron bars was as high as 2.39 mg / H (0.286 mg / cm ² · H). The amount of iron dissolved by using three iron bars increased.

Example 4
When one iron was put in salt water alone, one iron and one charcoal were contacted with a conductive material, and the dissolution situation of iron was examined when three charcoal were contacted with one iron with a conductive material. .
A 3% aqueous sodium chloride solution was added to a 3 L beaker. The iron bar used in the experiment was 2 mm in diameter and about 10 cm in length. The carbon rod (volume resistivity: 10 ⁻⁴ Ω · m) had a diameter of 5 mm and a length of about 10 cm. Both were set to soak in 4.5 cm in an aqueous sodium chloride solution. The surface area of the iron bar immersed in the salt water was 0.2 cm × 3.14 × 4.5 cm = 2.83 cm ² .
Experiment 4-1 (Comparative Example): One pure iron bar was set up vertically in a beaker.
Experiment 4-2 (Invention Example): One iron bar and one carbon bar were set up vertically in a beaker and connected with lead wires. The distance between the carbon bar and the iron bar was about 3.9 cm. The volume resistivity of the lead wire as the conductive material was 2 × 10 ⁻⁷ Ω · m.
Experiment 4-3 (Invention Example): One iron rod and three carbon rods (carbon rod 1, carbon rod 2, and carbon rod 3) were set up vertically in a beaker. The distance between the iron bar and the carbon bar was about 3.9 cm.
The iron bar and each carbon bar were connected with lead wires. The brine was stirred with a stirrer.
In addition, the volume resistivity of each of the lead wires as the conductive material was 2 × 10 ⁻⁷ Ω · m.
After a predetermined time elapsed, the iron bar was pulled up, washed with pure water, dried, and then weighed. Over time, the beaker containing the iron bar became reddish brown and became opaque due to the formation of precipitates. Table 4 shows the mass of the iron bar over time.

In Experiment 4-1, when the iron rod was immersed in salt water for 96 hours, the dissolution rate of iron was 0.24 mg / H (0.085 mg / cm ² · H).
When the carbon rod and the iron rod in Experiment 4-2 were connected with lead wires, the dissolution rate was 1.20 mg / H (0.424 mg / cm ² · H).
The dissolution rate of iron increased by 2.95 mg / H (1.04 mg / cm ² · H) when three carbon rods were connected to one iron bar in Experiment 4-3 with three lead wires. did.
When a large amount of iron is dissolved, it is effective to connect a plurality of carbon bars to one iron bar. In addition, when collect | recovering the melt | dissolution from iron, there exists an advantage which can reduce the quantity of a collection | recovery container in the direction where the number of iron bars used is small.

Example 5
We examined how the dissolution of iron was affected by the difference in size and area of iron and charcoal in salt water.
There were two types of carbon materials (volume resistivity: 10 ⁻⁴ Ω · m), rod-shaped (φ5 mm × 10 cm) and plate-shaped (12 cm × 4.2 cm × 8 mm: with terminal). There were two types of iron materials, rod-shaped (φ2 mm × 10 cm) and plate-shaped (12 cm × 4.5 cm × 0.5 mm). The upper end of the iron bar / iron plate and the engaging part of the alligator clip were polished with No. 2000 sandpaper and used.
The surface area of each material used was a carbon plate (82.62cm ^2), iron (68.7cm ^2), carbon rod (10.21cm ^2), were iron bar (4.1 cm ^2),
The carbon plate had a surface area of 82.62 cm ² , the iron plate had a surface area of 68.7 cm ² , the carbon rod had a surface area of 10.21 cm ² , and the iron rod had a surface area of 4.1 cm ² .
A 3% aqueous sodium chloride solution was added to a 2 L beaker. The length of the steel bar and the carbon bar immersed in the salt water was 6.5 cm, and the length of the steel plate and the carbon plate immersed in the liquid was 7.3 cm.
Further, the surface area of the horizontal bar that is immersed in the brine, 0.2cm × 3.14 × 6.5cm = 4.08cm 2, the surface area of the iron plate was a 66.9cm ^2.
Experiment 5-1 (Comparative Example): One iron bar was vertically set in salt water.
Experiment 5-2 (Invention Example): One iron bar and one carbon bar were connected by a lead wire. Their spacing was 1 cm.
Experiment 5-3 (Invention): One iron bar and one carbon plate were connected by a lead wire. Their spacing was 1 cm.
Experiment 5-4 (Comparative Example): One iron plate was placed vertically in salt water.
Experiment 5-5 (Invention): One iron plate and one carbon plate were connected by a lead wire. Their spacing was 1 cm.
Experiment 5-6 (Invention): One iron plate and one carbon rod were connected by a lead wire. Their spacing was 1 cm.
The salt water in the beaker was stirred at a rotation speed of 200 rpm using a stirrer.
In addition, the volume resistivity of each of the lead wires as the conductive material was 2 × 10 ⁻⁷ Ω · m.
After a predetermined time has elapsed, the iron material is pulled up and the mass is measured, and the mass of the iron bar or iron plate for each elapsed time is shown in Table 5-1.

The amount of iron dissolved varied depending on the combination of carbon and iron used. It was in Experiment 5-5 with a carbon plate and an iron plate that iron was dissolved most. The dissolution rate of iron was 16.3 mg / H (0.244 mg / cm ² · H). Then, in Experiment 5-3 for a carbon plate and a steel bar, the dissolution rate was 6.18 mg / H (1.51 mg / cm ² · H). Although the dissolution of iron was slight when the carbon rod was used, the use of the carbon plate significantly promoted the dissolution of iron. When a large amount of iron is dissolved in a short time, a carbon material having a large surface area is used. Further, when iron is dissolved, it is effective to increase the surface area of the iron material.
The current and voltage generated between the carbon plate and the iron plate were measured with a tester (Digital Tester M-04, Custom Co., Ltd.), and the results are shown in Table 5-2.

When a carbon plate was used (Experiments 5-3 and 5-5), a current of the order of mA was generated, and the carbon rod was of the order of μA. In all cases, the voltage was several hundred mV. The generation of a large amount of current promoted the dissolution of iron.
In the case where the iron material is melted intensively in a short time, it is effective to use a carbon plate.

Example 6
In fresh water, the state of dissolution of iron was examined when one carbon rod was brought into contact with three steel rods with a conducting material.
The aqueous solution used was a solution obtained by adding 6 mL of phosphorus standard solution (phosphorus concentration: 1000 mg / L) to 3 L of pond water. About 100 mL of pond water was added to a 100 mL beaker, and an iron bar and a carbon bar were inserted therein.
The iron bar used had a diameter of 2 mm and a length of about 10 cm, and the carbon bar (volume resistivity: 10 ⁻⁴ Ω · m) had a diameter of 5 mm and a length of about 10 cm. As for the used pond water, the solution was exchanged after measuring the mass of the iron bar after a predetermined time.
The following experiment was performed using this aqueous solution. Each beaker was stirred (200 rpm) with a magnetic stirrer.
Experiment 6: About 100 mL of pond water was added to a 100 mL beaker, and three iron bars and one carbon bar were set therein, and each was connected with a lead wire. The length of the steel bar in the water was 3.8 cm. The surface area of the iron bar immersed in water was 0.2 cm × 3.14 × 3.8 cm = 2.39 cm ² .
The distance between the carbon bar and the three steel bars was 3.4 cm (iron bar 1), 5.3 cm (iron bar 2), and 3.6 cm (iron bar 3), respectively.
In addition, the volume resistivity of each of the lead wires as the conductive material was 2 × 10 ⁻⁷ Ω · m.
After elapse of a predetermined time, the iron bar was pulled up, washed with water, dried and measured for mass. Table 6 shows the mass change of the iron bar.

The dissolution rates of the three iron bars were 0.14 mg / H, 0.13 mg / H and 0.15 mg / H. The total of the three was 0.42 mg / H (0.144 mg / cm ² · H). The distance between the carbon bar and the steel bar does not significantly affect the dissolution rate of the steel bar.

Example 7
When fresh steel was contacted with an iron rod, an iron rod and a carbon rod with a conductive material, and three carbon rods were contacted with one iron rod with a conductive material, the dissolution state of each iron was examined.
Pond water was added to a 3L beaker. The iron bar used in the experiment was 2 mm in diameter and about 10 cm in length. The carbon rod had a diameter of 5 mm and a length of about 10 cm. Both were set to soak in 4.5 cm in an aqueous sodium chloride solution. The surface area of the iron bar immersed in water was 0.2 cm × 3.14 × 4.5 cm = 2.83 cm ² .
Experiment 7-1 (Comparative Example): One pure iron bar was set up vertically in a beaker.
Experiment 7-2 (Invention Example): One iron bar and one carbon bar were set up vertically in a beaker and connected with lead wires. The distance between the carbon bar and the iron bar was about 3.9 cm. The volume resistivity of the lead wire as the conductive material was 2 × 10 ⁻⁷ Ω · m.
Experiment 7-3 (Invention): One iron rod and three carbon rods (carbon rod 1, carbon rod 2, and carbon rod 3) were set up vertically in a beaker. The distance between the iron bar and the carbon bar was about 3.9 cm.
The iron bar and each carbon bar were connected with lead wires. The volume resistivity of the lead wire as the conductive material was 2 × 10 ⁻⁷ Ω · m.
The pond water was stirred with a stirrer. After a predetermined time elapsed, the iron bar was pulled up, washed with pure water, dried, and then weighed. Over time, the beaker containing the iron bar became reddish brown and became opaque due to the formation of precipitates. Table 7-1 shows the mass of the iron bar over time.

Experiment 7-1: The dissolution rate of iron when the iron rod was immersed in pond water for 136 hours was 0.082 mg / H.
Experiment 7-2: The dissolution rate when the carbon rod and the iron rod were connected by the lead wire was 0.332 mg / H. It was about 4 times larger than the case of only a horizontal bar.
Experiment 7-3: When three carbon rods are connected to one iron rod with three lead wires, the dissolution rate of iron is 0.543 mg / H, which is about 6.6 times that of the case of only an iron rod. Increased.
When a large amount of iron is dissolved, it is effective to connect a plurality of carbon bars to one iron bar. Moreover, when collect | recovering the melt | dissolution from iron, there exists an advantage which can reduce the quantity of a collection | recovery container in the direction where the number of iron bars used is small.
The current and voltage generated between the iron bar and the carbon bar were measured with a tester. The results are shown in Table 7-2.

The current generated in Experiment 7-2 in which a steel bar and a carbon bar were connected by a lead wire was 156 μA, and the voltage was 598 mV. On the other hand, the current and voltage in Experiment 7-3 in which three carbon rods were connected to the iron rod with lead wires were (85 μA, 345 mV), (75 μA, 331 mV), and (110 μA, 404 mV), respectively. When the three carbon rods were combined, the current was 270 μA and the voltage was 1080 mV. The current was 1.7 times and the voltage was 1.8 times that of Experiment 7-2 using one carbon rod. In addition, when the steel material and the carbon material were directly stopped with a rubber band, the above current and voltage could not be measured.

Example 8
The present invention can also be used as a countermeasure against burning. In other words, by installing in sea areas where seaweed and seaweed such as kelp and seaweed are depleted, it is possible to supply iron to proliferate plants and to regenerate seaweed beds. Here, iron fulvic acid is necessary for promoting the growth of plants, but fulvic acid is indispensable together with iron ions to produce iron fulvic acid. And in this invention, in order to generate | occur | produce fulvic acid, the production | generation of fulvic acid iron is attained by arrange | positioning humus around an iron material.

In order to confirm this, an experiment was conducted on the dissolution state of iron when iron and charcoal were contacted with a conductive material in salt water.
A 3% aqueous sodium chloride solution was added to a 2 L beaker. The iron bar used in the experiment had a diameter (φ): 2 mm and a length: about 10 cm. The carbon rod (volume resistivity: 10 ⁻⁴ Ω · m) had a diameter (φ): 5 mm and a length: about 10 cm. Both were set so as to be immersed in an aqueous sodium chloride solution by 6.0 cm, and were set up vertically in a beaker. The distance between the carbon bar and the iron bar was about 8 cm. The iron bar and the carbon bar were connected by a lead wire which is a conductive material. The length of the lead wire itself was about 34 cm. The volume resistivity of the lead wire was 2 × 10 ⁻⁷ Ω · m.
A humus was placed around the horizontal bar. 500 ml of humus (made by Akagi Horticulture) was placed in a cylindrical nylon mesh and formed into a mat having a width of 10 cm, a length of 10 cm, and a thickness of 3 cm. This was wound around a steel bar in a cylindrical shape and fixed from the outside.

Over time, the beaker became brown due to elution from humus and reddish brown due to dissolution of iron. The degree of reddish brown became stronger with time after 1 day and 2 days.

The weight of the horizontal bar was measured periodically. The initial weight of the iron bar was 2.44 g. After 1 day, it was 2.20 g, after 2 days it was 2.00 g, and after 4 days it was 1.62 g. This indicates that iron fulvic acid is produced.
The reason why the dissolution rate of iron is slightly low is that the stirring is not performed using a stirrer.

From the above results, it is possible to dissolve iron even if humus is placed around the iron, and the iron supply material according to the present invention effectively generates iron fulvic acid and develops it in the formation of seaweed beds in the sea. It was confirmed that it was possible.

Claims

An iron material, a carbon material, and a conductive material, wherein the iron material and the carbon material are arranged without being bound to each other, and the volume resistivity of the conductive material is 10 −4 Ω · m or less, and the conductive material Is an iron supply material to the environmental water connecting the iron material and the carbon material.
2. The iron supply material for environmental water according to claim 1, wherein the conductive material has a volume resistivity of 10 −7 Ω · m or less.
The iron supply material for environmental water according to claim 1 or 2, wherein the conductive material is made of metal or carbon fiber is covered with an insulating material.
The iron supply material for environmental water according to any one of claims 1 to 3, wherein the iron material is an iron material having a purity of 90% or more.
The iron supply material for environmental water according to any one of claims 1 to 4, wherein the iron material is at least one selected from a plate, a rod, a net, a tube, a sheet, or a lump.
The iron supply material for environmental water according to any one of claims 1 to 5, wherein the carbon material has a volume resistivity of 10 0 Ω · m or less, preferably 10 -4 Ω · m or less.
The iron supply material for environmental water according to any one of claims 1 to 6, wherein the carbon material is plate-shaped.
The iron supply material for environmental water according to any one of claims 1 to 7, wherein two or more carbon materials are connected to the iron material by a conductive material.
The iron supply material for environmental water according to any one of claims 1 to 8, wherein two or more iron materials are connected to the carbon material by a conductive material.
The iron supply material for environmental water according to any one of claims 1 to 9, wherein humus is in contact with at least a part of the iron material in addition to the iron supply material for the environmental water.
The iron supply material for environmental water according to claim 10, wherein the humus is disposed on the outer periphery of the iron material.
The iron supply material to the environmental water according to claim 10 or 11, which is wrapped with a self-shrinking lashing material from the outside of the mulch.
An environment in which the iron supply material for environmental water according to any one of claims 1 to 9 is installed in at least one environmental water selected from among rivers, lakes and seas, and iron is eluted into the environmental water. Supplying iron to water.
The iron supply material for environmental water according to any one of claims 10 to 12 is installed in at least one environmental water selected from among rivers, lakes, and seas, and iron is contained in the environmental water as an iron complex. A method of supplying iron to the environmental water to be eluted.
The iron supply method to the environmental water according to claim 13 or 14, wherein the surface area of the carbon material and / or the iron material in the environmental water is adjusted, and the elution amount of the iron content is adjusted as iron content or iron complex. Method.
A method for maintaining an iron supply material for environmental water in which only the iron material is taken out and replaced from the iron supply material for environmental water according to any one of claims 1 to 12.
A method for maintaining an iron supply material to environmental water by measuring the amount of electricity supplied to the conductive material of the iron supply material to the environmental water according to any one of claims 1 to 12, and determining a replacement time of the iron material.