JP2009291668A - Water area environment improving material and its use - Google Patents

Abstract

A water environment improving material capable of efficiently decomposing bottom mud, a method for oxidizing bottom mud using the same, and a method for decomposing organic matter contained in the bottom mud.
[MEANS FOR SOLVING PROBLEMS] A water environment improving material according to the present invention includes at least one hydrogen peroxide adduct selected from an alkali metal salt hydrogen peroxide adduct and an alkaline earth metal salt hydrogen peroxide adduct, and steel. Slag and / or iron ore.
[Selection figure] None

Description

  The present invention relates to a water environment improving material and use thereof, and more specifically, one or more hydrogen peroxides selected from hydrogen peroxide adducts of alkali metal salts and hydrogen peroxide adducts of alkaline earth metal salts. The present invention relates to a bottom environment improving agent capable of decomposing bottom mud, including an adduct and steel slag and / or iron ore, and a bottom mud oxidation method and bottom mud decomposition method using the same.

  In recent years, bays, rivers, lakes, etc. throughout the country are said to have an increasing number of places where the water environment and sediment contamination are expanding. Contamination of the aquatic environment and sediment is due to an increase in the inflow of organic matter from domestic wastewater and livestock wastewater, and organic matter accumulates thickly on the bottom of the sea, riverbed, and lake as thicker than the natural circulation purification capacity. There are also many places. In places where pollution is conspicuous, such as in closed waters, oxygen in the water is consumed due to decomposition of bottom mud such as sludge accumulated on the seabed due to poor exchange of seawater, generating hydrogen sulfide that is toxic to living organisms and poor oxygen Phenomenon such as drowning of ecosystems due to commutation has occurred, causing great damage to fishery and living environment.

  One method for improving such an aquatic environment is to supply oxygen to the bottom layer. However, conventionally, a method of directly bubbling oxygen gas or air has been generally performed. However, since oxygen gas or air is supplied by a compressor or the like, not only energy is required but also several tens of oxygen supply points are used. It was only temporarily effective in a narrow area within meters. In addition, since the oxygen supply device is large and immersed in water, there are many problems such as high device installation costs, running costs, and maintenance costs.

As another method, a granule for improving sediment is known that contains slaked lime and an oxygen supply agent such as calcium peroxide and has self-disintegrating properties (Patent Document 1).
Patent No. 2719716 (registered on November 21, 1997)

  However, the invention described in Patent Document 1 is intended only for raising the pH of the sediment by slaked lime and supplying oxygen by the hydrogen peroxide adduct, and is not intended for the decomposition of the bottom mud. It is not possible to decompose the bottom mud and to prevent the hypoxia of the water area.

  The present invention has been made in view of the above problems, and its object is to improve a water environment that can efficiently decompose bottom mud, a method for oxidizing bottom mud and a method for decomposing bottom mud using the same. Is to provide.

  As a result of intensive investigations on a water environment improving material that can supply a sufficient amount of oxygen to a water area such as sediment in a short time and that can efficiently decompose bottom mud, hydrogen peroxide such as sodium percarbonate is obtained. The water area environment improving material containing the adduct and steel slag and / or iron ore can supply oxygen to the water area in a short time and can efficiently decompose the bottom mud, thereby completing the present invention. It came to do.

  The water environment improving material according to the present invention comprises at least one hydrogen peroxide adduct selected from hydrogen peroxide adducts of alkali metal salts and alkaline earth metal salts, steel slag and / or And iron ore.

  Steel slag is a by-product generated in large quantities from the steel industry, and is useful as an iron source, and can elute ferrous ions gently in water. In addition, the steel industry and steelmaking / rolling industry are designated as specific resource-saving industries by the Law for Promotion of Effective Utilization of Resources, and the promotion of the use of steel slag is strongly demanded. Also, iron ore can elute ferrous ions in water more slowly than steel slag.

  According to the above configuration, since ferrous ions are gently supplied by steel slag and / or iron ore, hydroxy radicals can be continuously generated from hydrogen peroxide derived from the hydrogen peroxide adduct by the Fenton reaction. it can. On the other hand, hydrogen peroxide, which is generated by decomposition of the hydrogen peroxide adduct and does not react with ferrous ions, is decomposed and oxygen is supplied. Therefore, the bottom mud can be oxidized in a short time and the bottom mud can be radically decomposed continuously. Moreover, since oxygen is supplied, even if the bottom mud is decomposed, an oxygen-poor state is not caused. Therefore, since it is possible to avoid an anoxic state while preventing drought of the water area, the water area environment including the sediment can be improved efficiently and continuously.

  In the water environment improving material according to the present invention, the hydrogen peroxide adduct is preferably sodium carbonate peroxide. Sodium carbonate peroxide generates hydrogen peroxide in the process of decomposition, and can generate hydroxy radicals by the catalytic action of ferrous ions. Therefore, according to the said structure, radical decomposition | disassembly of bottom mud can be advanced efficiently.

  In the water environment improving material according to the present invention, the hydrogen peroxide adduct is preferably a calcium carbonate peroxide.

  Calcium carbonate can stably hold hydrogen peroxide, and hydrogen peroxide is gradually released as calcium carbonate gradually dissolves in water. Therefore, according to the said structure, the water environment improvement material with sustained release and continuity can be provided.

  The bottom mud oxidation method according to the present invention is characterized in that the water environment improving material according to the present invention is added to the water area.

  According to the above configuration, the hydrogen peroxide adduct contained in the water environment improvement material is decomposed to generate hydrogen peroxide, which is derived from the steel slag and / or iron ore contained in the water environment improvement material. Reacts with the ferrous ion of this to produce hydroxy radicals. Further, hydrogen peroxide that has not reacted with ferrous ions is decomposed to generate oxygen.

  Therefore, even extremely reductive bottom mud can be promptly improved to an oxidative state. Therefore, the bottom mud can be easily decomposed and the bottom mud can be rapidly oxidized and decomposed. Moreover, the poor oxygen state of a water area can be improved.

  The method for decomposing bottom mud according to the present invention is characterized by including Step 1 for adding the water environment improving material according to the present invention to water and Step 2 for irradiating light to the reduced-type bottom mud.

  According to the said structure, the hydrogen peroxide produced | generated by step 1 decomposes | disassembles, generate | occur | produces oxygen, supplies oxygen to bottom sediment, and oxidizes bottom mud. In Step 2, hydroxy radicals are generated by the Fenton reaction, and the bottom mud is strongly decomposed. This decomposition process (photooxidation of the bottom mud) is coupled with a reaction of reducing ferric ions to ferrous ions, and can form a catalytic cycle of iron. Therefore, bottom mud can be decomposed without replenishing ferrous ions. As a result, the bottom mud can be decomposed very efficiently.

  As described above, the water environment improving material according to the present invention includes at least one or more alkali metal salt or alkaline earth metal salt hydrogen peroxide adduct and steel slag and / or iron ore. It is.

  Therefore, since an anoxic state can be avoided while preventing the eutrophication of the water area, there is an effect that the water area environment such as sediment can be improved continuously and efficiently.

  An embodiment of the present invention will be described as follows, but the present invention is not limited to this.

(1. Water environment improvement material)
In one embodiment, the water environment improving material according to the present invention includes at least one hydrogen peroxide adduct selected from a hydrogen peroxide adduct of an alkali metal salt and a hydrogen peroxide adduct of an alkaline earth metal salt, Steel slag and / or iron ore.

  The above-mentioned “hydrogen peroxide adduct of alkali metal salt” and “hydrogen peroxide adduct of alkaline earth metal salt” are substances in which hydrogen peroxide forms an adduct with an alkali metal salt or an alkaline earth metal salt. Any hydrogen peroxide adduct that can dissociate in water and release hydrogen peroxide may be used. Examples thereof include sodium carbonate peroxide, potassium carbonate peroxide, calcium carbonate peroxide, barium carbonate peroxide, magnesium carbonate peroxide, and calcium oxide peroxide. Since the hydrogen peroxide adduct dissociates in water and easily releases hydrogen peroxide, it can act as a hydrogen peroxide supply source.

  The hydrogen peroxide adduct may be one or more hydrogen peroxide adducts selected from hydrogen peroxide adducts of alkali metal salts and hydrogen peroxide adducts of alkaline earth metal salts. For example, a hydrogen peroxide adduct of an alkali metal salt or a hydrogen peroxide adduct of an alkaline earth metal salt may be used alone, or a hydrogen peroxide adduct of an alkali metal salt and / or an alkaline earth metal salt may be used. Two or more hydrogen peroxide adducts may be used in combination.

  In the present specification, the term “steel slag” is synonymous with iron ore and refers to an oxide melt discharged from a dry smelting process or a solidified body thereof (Rikagaku Dictionary 4th edition, page 669, Iwanami Shoten) . Iron and steel slag is mainly composed of gangue components in ore separated from the target metal in the furnace and ash in the fuel, but it may contain melting materials added to lower the melting point and improve fluidity. Good. Steel slag includes calcium-containing compounds such as calcium chloride, slaked lime, lime nitrogen, lime-lime, limestone, calcium carbonate, and shells, phosphorus-containing compounds such as phosphate, phosphoric acid, potassium chloride, potassium sulfate, potassium nitrate, etc. Potassium-containing compounds, urea, ammonium sulfate, ammonium nitrate, etc. may be added.

  The steel slag may be, for example, either blast furnace slag or steelmaking slag, and the blast furnace slag may be slowly cooled slag or granulated slag. The steelmaking slag may be converter slag or electric furnace slag, and the electric furnace slag may be oxidized slag or reduced slag. In addition, only one type of these steel slags may be used, or a plurality of types may be used in combination.

  Thus, although it does not specifically limit as steel slag, A blast furnace granulated slag can be used preferably especially. Blast furnace granulated slag is a kind of steel slag generated as a by-product in the steel manufacturing process, and is generated in the steel making process. Steelmaking slag is known to elute inorganic nutrient salts such as phosphorus and silicon. For this reason, in the place where bottom sediment pollution is remarkable and eutrophication progressed, use of granulated blast furnace slag is suitable. Blast furnace granulated slag is used to improve the environment of the water area (for example, Japanese Patent Application Laid-Open No. 2004-24204). It is different from the intended use.

  The particle size of the steel slag is not particularly limited. Moreover, although the composition and specific gravity of steel slag are not particularly limited, it is preferable that the steel slag is precipitated at the bottom of the water in order to increase the decomposition efficiency of the bottom mud.

  Since iron and steel slag can release ferrous ions gradually, it can continuously react with hydrogen peroxide supplied from the hydrogen peroxide adduct to generate hydroxy radicals. And the said hydroxyl radical can decompose | disassemble bottom mud by radical reaction. Thus, since the water environment improvement material which concerns on this invention can decompose | disassemble bottom mud continuously, not temporarily, it is very useful for the environmental improvement of sediment.

  Iron ore is also useful for the continuous decomposition of bottom mud, similar to steel slag. The iron ore is not particularly limited, and hematite, magnetite, pyrite, rhyolite or the like can be used. Only one type of the iron ore may be used, or two or more types may be used in combination. The form of the iron ore is not particularly limited, but since it is preferable to increase the surface area in order to facilitate the release of ferrous ions, it is preferably in a powder form.

  In the water environment improving material, steel slag and / or iron ore acts as a catalyst, so the mixing ratio is not particularly limited. Further, the ratio of the hydrogen peroxide adduct is preferably about 0.5 to 1% by weight with respect to 100% by weight of the water environment improving material, since foaming is gentle. However, since the proportion of hydrogen peroxide adduct in the water environment improving material depends on the degree of bottom mud reduction, the specific ratio is not limited, and is appropriately determined based on the degree of bottom mud reduction. Just decide.

  The method for producing the water environment improving material is not particularly limited. For example, it can be produced by appropriately mixing the hydrogen peroxide adduct and steel slag and / or iron ore using a conventionally known stirrer or the like. Moreover, the form of the said water area environment improvement material is not specifically limited, According to the intended purpose, it can change suitably. For example, it may be a powder or a pellet tablet.

  For example, when the purpose is to prevent or maintain the environmental degradation of the bottom sediment, granulate into pellets and make hydrogen peroxide and oxygen generated more slowly than the powdery water environment improver, What is necessary is just to be able to perform oxidative decomposition of bottom mud continuously.

  In addition, when it is desired to improve the environment immediately, a powdery water environment improving material may be mixed with the bottom mud. Thereby, the supply of oxygen and the increase of the oxidation-reduction potential are performed more quickly than when pellet-shaped tablets are used, and as a result, oxidative decomposition of the bottom mud can be promoted.

  The particle size of the powdery water environment improving material is not particularly limited. The method for preparing the powder is not particularly limited, and may be prepared using a conventionally known roll mill or the like, and the particle size may be prepared using a JIS standard sieve or the like as necessary.

  Moreover, the method for performing the granulation is not particularly limited. For example, the powdery water area environment improving material is subjected to pressure molding using a briquette machine, rolling granulation using a drum or pan, and an extrusion molding machine. It may be appropriately granulated by using a conventionally known granulation method such as granulation by the above. When granulating the water environment improving material, it is preferable that the volume expands when water is contained, and the granulated composition collapses itself to increase the specific surface area. Therefore, disintegrating agents such as quick lime, baked dolomite, and montmorillonite may be appropriately mixed before granulation. Thereby, even when it granulates, since the specific surface area of a water environment improvement material can be enlarged, Fenton reaction can be advanced rapidly and reaction efficiency can be improved.

  The specific gravity of the granulated aquatic environment improvement material is not particularly limited, but when it is intended to settle slowly, a specific gravity of 1.1 to 1.2 is preferable, and it sinks into the sediment. Is intended to have a specific gravity of 1.2 or more.

  The water environment improving material may contain the hydrogen peroxide adduct and other components other than steel slag and / or iron ore. Examples of the other components include a binder. Although it does not limit as a binder, For example, water glass, magnesium salt, sodium hydroxide etc. can be mentioned. Moreover, it is preferable that content in the said water area environment improving agent of the said other component is 35 weight% or less.

  In one embodiment, in the water environment improving material according to the present invention, the hydrogen peroxide adduct is preferably sodium carbonate peroxide. An aqueous solution of sodium carbonate peroxide is easily decomposed into sodium carbonate and hydrogen peroxide, and thus is useful as a supply material for hydrogen peroxide. The generated hydrogen peroxide generates hydroxy radicals by ferrous reaction with ferrous ions derived from steel slag and / or iron ore, and the hydroxy radicals are used for radical decomposition of bottom mud.

  Generation of hydrogen peroxide from sodium carbonate peroxide is represented by the following formula (1), and generation of hydroxy radicals is represented by the following formula (2).

2Na ₂ CO ₃ .3H ₂ O ₂ + 2H ₂ O → 4Na ⁺ + 2HCO ₃ ⁻ + 2OH ⁻ + 3H ₂ O ₂ (1)
Fe ²⁺ + H ₂ O ₂ → Fe ³⁺ + HO ^· + OH ⁻ (2)
In another embodiment, in the water environment improving material according to the present invention, the hydrogen peroxide adduct is preferably a calcium carbonate peroxide. As described above, calcium carbonate can stably hold hydrogen peroxide, and hydrogen peroxide is gradually released as calcium carbonate gradually dissolves in water. Therefore, it is particularly effective when continuous bottom mud decomposition is desired.

  The calcium carbonate peroxide may be a natural product, but may be artificially retained in calcium carbonate. The method for retaining the peroxide in calcium carbonate is not particularly limited, and for example, a method of spraying vapor of hydrogen peroxide on calcium carbonate can be mentioned. In this case, as shown in the following formula (3), hydrogen peroxide is held in calcium carbonate.

2CaCO ₃ + 3H ₂ O ₂ → 2CaCO ₃ · 3H ₂ O ₂ (3)
As the calcium carbonate, it is not always necessary to use a pure product. For example, a calcium carbonate-based material such as oyster shell or limestone may be used. In this case, oyster shells, limestone or the like in which hydrogen peroxide is held by a method such as spraying of hydrogen peroxide vapor may be used as the calcium carbonate peroxide. In this case, the form of oyster shells, limestone, etc. holding hydrogen peroxide is not particularly limited. For example, it may be in the form of powder or lump, and may be used as it is without crushing oyster shells or limestone. However, since more hydrogen peroxide can be retained by increasing the surface area of oyster shells or the like, it is preferably in the form of powder.

  In addition, said "main component" means containing 50 weight% or more of calcium carbonate when the weight of the thing which has calcium carbonate as a main component, such as oyster shell, is 100 weight%. Generation of hydrogen peroxide from calcium carbonate peroxide is represented by the following formula (4).

2CaCO ₃ .3H ₂ O ₂ + 2H ₂ O → 2Ca ²⁺ + 2HCO ₃ ⁻ + 2OH ⁻ + 3H ₂ O ₂ (4)
Hydrogen peroxide generated by the reaction represented by the formula (4) is used for generation of hydroxy radicals by the Fenton reaction as shown in the formula (2).

  Thus, the hydrogen peroxide derived from the water environment improving material according to the present invention generates hydroxy radicals by Fenton reaction with ferrous ions derived from steel slag and / or iron ore. On the other hand, hydrogen peroxide that has not reacted with ferrous ions is decomposed to generate oxygen. Therefore, due to the generation of the hydroxy radical and oxygen, the redox potential of the sediment is raised to an oxidative state. Therefore, oxidative decomposition of bottom mud can be promoted. Also, hydrogen sulfide can be removed by oxidation.

  When the hydrogen peroxide adduct is calcium carbonate peroxide, the calcium ions generated by the reaction shown in the formula (4) neutralize the bottom mud, so that the pH of the bottom mud can be raised. As a result, sulfate-reducing bacteria can be inactivated. In addition, calcium sulfide and hydrogen sulfide react to produce calcium sulfide, thereby reducing hydrogen sulfide. Furthermore, when oyster shells are used as the main component of calcium carbonate, there is a merit that oyster shells that are normally discarded can be effectively used to improve the bottom sediment. Can contribute.

  In this specification, the term “water area” includes water quality and bottom sediment (bottom mud), and also includes both seawater and fresh water areas. The term “sediment” is synonymous with the term “bottom mud” and refers to sediment containing organic matter and / or nutrients deposited at the bottom of the water area. For example, sludge can be mentioned. The specific component of the organic substance is infinite and is not particularly limited. Examples of the nutrient salts include salts formed by nitrogen and phosphorus.

  Although the usage method of the said water area environmental improvement material is not specifically limited, It is preferable to use by spraying in a water area. Sprinkling in the water area is basically based on a method in which the water environment improving material is introduced from the water or from the water, but may be a method of spraying the water environment improving material on the bottom mud. In order to surely reach the bottom mud and react with the bottom mud, it is preferable to use a granulated water environment improving material. Moreover, you may mix the said water area environment improving material directly into bottom mud. Although there are no particular limitations on the amount of application and the frequency of application, it is preferable to periodically investigate the bottom and water environment of the application area and adjust the application amount and application frequency as appropriate.

(2. Bottom mud oxidation method)
The method for oxidizing the bottom mud according to the present invention is to add the water environment improving material according to the present invention to the water area.

  By adding the water environment improving material according to the present invention to the water area, the hydrogen peroxide adduct contained in the water environment improving material is easily decomposed, and hydrogen peroxide as represented by the above formulas (1) and (4) is obtained. Is generated. The hydrogen peroxide adduct is as already described.

  The hydrogen peroxide reacts with ferrous ions contained in the steel slag and / or iron ore contained in the water environment improving material, and generates hydroxy radicals as shown in the above formula (2).

  Further, hydrogen peroxide that has not reacted with ferrous ions is decomposed to generate oxygen. By adding the water environment improving material according to the present invention to the water area, the hydroxy radicals and oxygen are generated, the redox potential of the sediment is increased, and the sediment is changed to an oxidative state. It can be in a state where it can be easily decomposed. Moreover, the poor oxygen state of a water area can be improved.

  The method for adding the water environment improving material to the water is not particularly limited. For example, the method of spraying in a water area, the method of mixing the said water area environment improvement material directly into bottom mud, etc. can be mentioned.

(3. Decomposition method of bottom mud)
The method for decomposing bottom mud according to the present invention includes Step 1 for adding the water environment improving material according to the present invention to the water area and Step 2 for irradiating the reduced bottom mud with light. FIG. 1 shows a conceptual diagram of a method for decomposing bottom mud according to the present invention.

  By adding the water environment improving material according to the present invention to the water area, the hydrogen peroxide adduct contained in the water environment improving material is easily decomposed, and hydrogen peroxide as represented by the above formulas (1) and (4) is obtained. Is generated. The hydrogen peroxide adduct is as already described.

  The hydrogen peroxide reacts with ferrous ions contained in the steel slag and / or iron ore contained in the water environment improving material, and generates hydroxy radicals as shown in the above formula (2).

  The hydroxy radical can oxidatively decompose the bottom mud by extracting hydrogen from the bottom mud by radical reaction. Thus, in the method according to the present invention, when the water environment improving material is added to the water area, hydrogen peroxide and / or oxygen is generated from the hydrogen peroxide adduct, and the generated hydrogen peroxide is converted into steel slag and / or Or it decomposes | disassembles by the Fenton reaction with the ferrous ion loosely supplied from an iron ore, a hydroxy radical produces | generates, and the said hydroxy radical decomposes | disassembles bottom mud oxidatively. Therefore, the eutrophic state of the sediment can be resolved continuously and efficiently.

  The above water area is not particularly limited, but in particular, if the bottom mud decomposition method according to the present invention is applied to closed water areas such as inner bays, inland seas and lakes where a large amount of bottom mud is accumulated in the sediment. The environment of the water area can be greatly improved. In particular, it is most effective to apply this method to water areas where a large amount of mud is accumulated in the sediment due to eutrophication.

  By adding the water environment improving material to the water area, ferrous ions derived from steel slag and / or iron ore are oxidized to ferric ions as shown in FIG. In combination with this reaction, a hydroxy radical is generated. On the other hand, ferric ions are reduced to ferrous ions by oxidation of reduced-type bottom mud under light irradiation. Since ferric ions are reduced again to ferrous ions in this way, iron can always be kept in a divalent dissolved state with high solubility. Moreover, since it is not necessary to supplement ferrous ion and it can be used repeatedly, the iron catalyst cycle (iron cycle) shown in FIG. 1 can be accelerated, and the decomposition efficiency of bottom mud can be improved. .

  The “reduced bottom mud” refers to bottom mud having a negative oxidation-reduction potential. The method for irradiating the reduced-type bottom mud with light is not particularly limited. For example, sunlight may be irradiated to the reduced bottom mud, or light may be irradiated using a conventionally known light source. Examples of the light source include a point light source such as a light emitting diode and a linear light source such as a fluorescent lamp. The wavelength of the irradiated light is not particularly limited, and the oxidation reaction can proceed if the light is in the visible to ultraviolet region.

  By oxidizing the reduced-type bottom mud with light, ferric ions are simultaneously reduced to ferrous ions, and the redox potential of the bottom mud turns positive.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the embodiments can be obtained by appropriately combining technical means disclosed in different embodiments. The form is also included in the technical scope of the present invention.

[Oxidation of bottom mud by water environment improvement material]
(1) Blast-furnace granulated slag (particle size 1-3 mm; JFE, PTC slag) 10% by weight with respect to 100% by weight of the bottom mud of the Okawa cove (Hiroshima City, Hiroshima Prefecture) from which bentos were removed (2) 0.5% by weight of sodium carbonate peroxide (sodium percarbonate PC-2; Matsuo Pharmaceutical Co., Ltd.) or (3) 0.5% by weight of sodium carbonate peroxide and blast furnace water Add and mix 10% by weight of crushed slag, fill it into 84.5ml sealed containers (3 test stands each), cover with a lid and leave under sunlight, abbreviated as "ORP" ) Was measured over time. Hereinafter, the above (1) is referred to as a blast furnace granulated slag zone, (2) as a sodium carbonate peroxide zone, and (3) as a combined zone. As a control, only bottom mud was used.

  FIG. 2 shows the temporal change of ORP in each test section. No increase in ORP was observed in the granulated blast furnace slag. When the sodium carbonate peroxide group and the combination group were compared, the combination group showed a significant increase in the initial ORP and showed a higher ORP tendency than the sodium carbonate peroxide group throughout the test period.

  Sodium carbonate peroxide alone is mainly oxidized only by oxygen originating from hydrogen peroxide, but when used in combination with granulated blast furnace slag, slag becomes an iron source and simultaneously generates hydroxy radicals by the Fenton reaction shown in Formula (2). It is considered that the ORP could be further increased due to progress. In this way, the extremely small amount of material (0.5 wt% sodium carbonate peroxide + 10 wt% blast furnace granulated slag) can be used to form extremely reductive bottom mud in an extremely short time (within 30 minutes). It can be said that it is very useful because it can be improved to an oxidative state.

  The water environment improving material according to the present invention comprises at least one hydrogen peroxide adduct selected from hydrogen peroxide adducts of alkali metal salts and alkaline earth metal salts, steel slag and / or Therefore, the bottom mud can be efficiently decomposed. Therefore, it can be widely used in industries such as fisheries, fisheries industry, environmental industry, and steel industry.

FIG. 1 shows a conceptual diagram of a method for decomposing bottom mud according to the present invention. FIG. 2 shows the temporal change of ORP in (1) blast furnace granulated slag section, (2) sodium carbonate peroxide section, and (3) combined use section in the examples.

Claims (5)

  One or more hydrogen peroxide adducts selected from hydrogen peroxide adducts of alkali metal salts and alkaline earth metal salts, and steel slag and / or iron ore, To improve water environment.   The water environment improving material according to claim 1, wherein the hydrogen peroxide adduct is sodium carbonate peroxide.   The water environment improving material according to claim 1, wherein the hydrogen peroxide adduct is calcium carbonate peroxide.   The method for oxidizing bottom mud, comprising adding the water environment improving material according to any one of claims 1 to 3 to the water area. Step 1 of adding the water environment improving material according to any one of claims 1 to 3 to the water area;
And a step 2 of irradiating the reduced-type bottom mud with light.

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