JP2003329223A - Incineration method for suppressing production of dioxins and catalyst for incineration - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combustion incinerating method more effective for lowering dioxins. <P>SOLUTION: In this incineration method, organic waste is burnt interposing particles of iron-based microscopic metallic material coated with a metal oxide layer, where an average particle diameter is 0.01-5.0 μm and an average valence n+ of iron in the particles satisfies 0<n<2.5. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for incinerating organic waste that can suppress the production of dioxins even under combustion conditions where the combustion temperature is low. Specifically, the present invention relates to a method for incinerating an organic waste in which iron-based particles are interposed and the production of dioxins can be suppressed by its catalytic action, or a catalyst for incinerating an organic waste.

[0002]

2. Description of the Related Art In Japan, combustible waste is normally incinerated. Japan is a country with an extremely high rate of dependence on refuse incineration globally. For this reason, many municipalities and companies incinerate waste. The generation of dioxins associated with this incineration has become a major social problem. Here, dioxins are halogenated (chlorinated, brominated) dibenzo-p.
-Dioxins and dibenzofurans.
In the case of incineration of refuse, if it is possible to continue incineration at high temperature, it is possible to completely combust the refuse, so that chlorine compounds can also be decomposed by heat and chlorine gas and hydrogen chloride gas are generated. The occurrence of highly toxic dioxins is relatively low. However, it cannot be said that incineration is always carried out under good incineration conditions, and when the incineration conditions are not good, particularly when the combustion temperature is low, the dioxins may be produced. Dioxins are difficult to be decomposed in the natural world, enter the human body through water and food, accumulate in the body and show carcinogenicity, and their carcinogenicity is problematic. In response to this, local governments and companies are abolishing existing incomplete combustible incinerators and combustion methods and constructing new incinerators. Furthermore, a combustion technology that can reduce dioxins by utilizing the existing incinerator is being sought.

Heretofore, various reports have been made as prior art on absorption and decomposition of highly toxic dioxins. For example, in Japanese Unexamined Patent Publication No. 4-371714, after cooling exhaust gas generated from a refuse incinerator, harmful components such as dioxins are adsorbed by an adsorbent containing cement, and dust is separated and collected together with the adsorbent by dust collection, A method of kneading and solidifying and treating is disclosed, and Japanese Patent Publication No. 6-38863 discloses a polyhalogen having at least 5 carbon atoms by heating at 200 to 550 ° C. in the presence of a catalyst such as iron oxide. A method for decomposing a halogenated aromatic compound is disclosed in Japanese Patent Application Laid-Open No. 2-280816. Heat treatment is performed at a temperature of 300 to 700 ° C. in the presence of a catalyst containing iron oxide to produce a halogenated aromatic compound from exhaust gas. A method of removing or reducing the like is disclosed. In addition, JP-A-8-27
Japanese Patent No. 0924 discloses a method of burning combustible waste at a temperature of 850 ° C. or higher in the presence of a calcium compound and iron oxide particles. Further, in Japanese Patent Laid-Open No. 9-89228, it is disclosed that ferric oxide hydroxide particles or iron oxide particles having a sulfur and sodium content of a predetermined amount or less and incinerator are coexisted and burned in a combustion furnace. A characteristic incineration method is disclosed. Further, in Japanese Patent Laid-Open No. 11-267507, a method for incinerating refuse is characterized in that iron oxide powder or hydrous iron oxide powder having a predetermined activity is spray-added as a catalyst to a combustion chamber or the like and brought into contact with combustion gas. Is disclosed.

The methods disclosed in the above publications have not been sufficient as effective combustion techniques capable of reducing dioxins. That is, the above-mentioned JP-A-4
The method described in JP-A-371714 is a method of adsorbing dioxins and the like generated on the surface of cement that is porous in the bag filter portion, and the dioxins are basically transferred from the exhaust gas to the cement. It is necessary to detoxify the cement that has adsorbed dioxins instead of suppressing it. In the method described in Japanese Patent Publication No. 6-38863, a polyhalogenated cycloalkyl compound and a polyhalogenated aromatic compound are prepared by subjecting fly ash generated in an incinerator to a catalyst such as iron oxide, calcium carbonate and sodium carbonate in a fixed bed. However, it is practically impossible to construct such a detoxification facility for fly ash in the latter stage of the incinerator, because enormous capital investment is required. JP-A-8-270924, JP-A-9-
The iron compound catalysts disclosed in JP-A No. 89228 or JP-A No. 11-267507 have an effect of reducing dioxins, but there is room for further improvement particularly in suppressing the generation of dioxins at low temperature combustion. .

[0005]

DISCLOSURE OF THE INVENTION Technical Problem It is a technical object of the present invention to provide a more effective combustion incineration method capable of reducing dioxins, and a dioxin production suppression catalyst used when incinerating organic waste. And

[0006]

The above technical problems can be achieved by the present invention as described below. That is, the present invention is a particle in which a metal portion mainly composed of iron having an average particle diameter of 0.01 to 5.0 μm is coated with a metal oxide layer, and the average valence number n + of iron in the particle is 0 <n. Intervening particles that are <2.5,
This is an incineration method that incinerates organic waste. Further, the present invention is a particle in which a metal portion mainly composed of iron having an average particle diameter of 0.01 to 5.0 μm is coated with a metal oxide layer, and the average valence number n + of iron in the particle is 0 <n. Of particles that are <2.5,
It also provides use as a catalyst for suppressing the generation of dioxins used when incinerating organic waste.

More specifically, the present invention provides (1) particles having an average particle diameter of 0.01 to 5.0 μm, which is a fine metal material mainly composed of iron and coated with a metal oxide layer, An incineration method characterized by incinerating an organic waste by interposing particles having an average iron valence number n + of particles of 0 <n <2.5, (2) Composition of iron with respect to total metal elements in the particles (1) wherein the ratio is 60% by weight or more
(3) The specific surface area of the particles is 0.5
To 200 m ² / g, the incineration method according to (1) above, and (4) the particles are metallic magnetic particles contained in a magnetic recording medium or a magnetic paint. ) Incineration method described in.

The present invention also provides (5) an average particle size of 0.0
1 to 5.0 μm of particles in which a fine metal material mainly composed of iron is covered with a metal oxide layer, and the particles have an average valence n + of iron of 0 <n <2.5 An incineration method characterized by incinerating an organic waste by interposing a waste material of a magnetic recording medium or a magnetic coating material, or a treated material thereof, (6) The composition ratio of iron to total metal elements in particles is 60% by weight. The incineration method according to (5) above, wherein the specific surface area of the particles is
The incineration method according to (5) above, wherein the incineration method is 0.5 to ²⁰⁰ m ² / g.

Further, according to the present invention, (8) an average particle in which a fine metal material mainly containing iron is coated with a metal oxide layer, and the average valence number n + of iron is 0 <n <2.5. Diameter 0.0
1 to 5.0 μm particulate organic waste incineration catalyst,
(9) The organic waste incineration catalyst according to (8) above, wherein the composition ratio of iron to the total metal elements is 60% by weight or more, (10) the specific surface area is 0.5 to 20.
The organic waste incineration catalyst according to (8) above, which is 0 m ² / g, and (11) the above-mentioned metal magnetic particles contained in a magnetic recording medium or a magnetic paint. 8) A catalyst for incineration of organic waste according to 8).

Further, according to the present invention, (12) an average particle in which a fine metal material mainly composed of iron is coated with a metal oxide layer, and an average valence number n + of iron is 0 <n <2.5. Diameter 0.0
Waste material of a magnetic recording medium or magnetic paint containing particles of 1 to 5.0 μm, or an organic waste incineration catalyst containing a processed product thereof, (13) The composition ratio of iron to total metal elements in the particles is 60% by weight. % Or more, the organic waste incineration catalyst according to the above (12),
(14) The specific surface area of the particles is 0.5 to ²⁰⁰ m ² / g
The present invention relates to the organic waste incineration catalyst according to (12) above.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, particles in which a fine metal material mainly containing iron is coated with a metal oxide layer are used as a so-called catalyst when incinerating organic waste. In the present invention, the particles preferably have a composition ratio of iron to the total metal elements of the particles of about 60% by weight or more. And, as a constituent element other than iron, it is preferable that cobalt is contained at a ratio of about 30% by weight or less based on the total metal elements of the particles. Further, the particles used in the present invention, in addition to Fe and Co, have a weight ratio of about 20% by weight or less based on the total metal elements of the particles,
Al, Si, S, Ti, V, Cr, Cu, Y, Mo, R
h, Pd, Ag, Sn, Sb, Te, Ba, Sr, W,
Au, Pb, Bi, La, Ce, Pr, Nd, P, M
It is preferable to contain an element such as n, Zn, Sr, B or Ca. In addition to controlling the shape of the starting material, these elements are effective in preventing sintering between particles, promoting reduction, and controlling the shape and surface property of the reduced fine metal material.

The oxide film formed on the surface of the particles used in the present invention, that is, as the main oxide constituting the oxide layer coating the fine metal material mainly containing iron,
FeO _x (where x is 1.33 ≦ x ≦ 1.5, hematite, maghemite, magnetite, iron oxide in an intermediate oxidation state between maghemite and magnetite), Co _x Fe _(1-x) O
_y , (for example, CoFe ₂ O ₄ , CoFe ₃ O _4, etc.), in addition to which a small amount of the above elements such as Al, Mg, Si, Y,
Oxides in which a rare earth element, a metal such as Ca, Ba, Sr, or Ni is solid-solved, or a crystalline or amorphous metal oxide, oxyhydroxide, hydroxide, or hydrated oxide alone Or a composite is included. This oxide is mainly derived from the element added as a sintering inhibitor and the element added at the time of forming the fine metal material as a raw material.

The above-mentioned particles of the present invention are characterized in that the iron valence Fe ^{n +} as an average value of the entire particles is about 0 <n <2.5, preferably about 0 <n <2.0. And This value was calculated by dissolving the particles in a degassed water system with a non-oxidizing acid and determining the amount of hydrogen produced and the amount of Fe ²⁺ , Fe ³⁺ , Co ²⁺ eluted in the solution, and the particles in an oxidizing atmosphere. This can be done by weight gain associated with complete oxidation below. The change in charge due to the above-mentioned acid dissolution due to other components present in the particles can be ignored and is out of calculation. Regarding the above values, the range from magnetite to goethite or hematite, that is, the valence n of iron
Regarding the iron compound particles in which + is 2.66 ≦ n ≦ 3.0, JP-A-8-270924 and JP-A-9-8 are referred to.
No. 9228 and Japanese Patent Laid-Open No. 11-267507, and there are some effects (see Comparative Example). However, the region of the present invention is a region in which iron in the valence state of metal is involved, and this valence state is involved in improving the catalytic activity. The catalyst effect here is an incineration promoting effect, a dioxins production suppressing effect, and is exhibited by the particles in the incineration process. In this process, the particles composed of a fine metal material mainly composed of iron and a metal oxide layer covering the iron are oxidized as a whole by heating in an oxidizing atmosphere, and the metal in the fine metal material is However, it diffuses into the oxide layer, and the composition of the entire particle is made uniform. The chemical activity of the surface of the particles in this process promotes the oxidative incineration of organic waste, particularly organic waste containing halogen (chlorine, bromine) elements, and Suppresses the formation of organic cyclic compounds, so-called dioxins.

The shape of the particles of the present invention is granular, spherical,
It may be spindle-shaped or needle-shaped. And said
The average particle size of the particles is preferably about 0.01 to 5.0 μm.
Degree, more preferably about 0.02 to 3.0 μm,
Furthermore, it is preferably about 0.02 to 1.0 μm. grain
The oxidative stability of the child itself is provided, and it can be taken safely in air.
In order to be able to handle, the average of the particles
The particle size is preferably about 0.01 μm or more, and
To secure a specific surface area and to fully exert the catalytic effect
Has an average particle diameter of about 5.0 μm or less.
It is preferable. The average particle size of the particles is
By calculating the average value of the values measured from the microscopic photograph
Can be easily obtained. Also, the ratio of the particles of the present invention
Surface area is preferably about 0.5-200 m^Two/ G,
More preferably about 1.0 to 200 m^Two/ G, further
Preferably about 2.0 to 100 m^Two/ G. particle
It has its own oxidative stability and can be handled safely in air.
In order to be able to
Product is about 0.5m ^Two/ G or more is preferable,
To secure the number of active sites and to fully exert the catalytic effect
The specific surface area of the particles is about 200 m^Two/ G or less
Is preferred. The specific surface area of the particles is
Easy to obtain by measuring according to the BET method
You can

The particles of the present invention can be easily obtained by a known method. For example, iron-based oxides containing the above-mentioned elements (for example, hematite, maghemite, magnetite, iron oxide in an intermediate oxidation state between maghemite and magnetite), and hydrous oxides (for example, goethite, akagenite, lepite). Fine metal materials by a method such as docrosite), an inorganic salt or an organic acid salt (for example, hydrochloride, sulfate, acetate, oxalate, etc.) in the gas phase with a reducing gas or a wet reduction method. Can be obtained. In the production of the fine metal material, a compound of a specific element may be added so as to segregate in the vicinity of the surface for the purpose of preventing sintering during reduction or maintaining the shape. Then, after the reduction, a method of impregnating with an organic solvent such as toluene and drying, a method of immersing in an organic solvent such as toluene and blowing an oxidizing gas to dry it, and blowing an oxidizing gas with a partial pressure adjusted without using an organic solvent By the method, a thin oxide film is formed on the surface to impart oxidative stability. Examples of the oxidizing gas at this time include oxygen gas or a mixed gas of oxygen gas such as air and an inert gas (nitrogen, argon, helium, etc.).

One embodiment of the method for producing the above particles of the present invention will be described in detail below, but the method for producing the above particles used in the present invention is not limited thereto. First, as a method for producing a goethite powder which is a hydrous oxide mainly containing iron containing the above-mentioned elements, for example, a ferrous salt and one kind selected from alkali hydroxide, alkali carbonate and ammonia, or An oxygen-containing gas such as air is passed through a suspension containing a ferrous hydroxide-containing precipitate such as iron hydroxide or iron carbonate, which is obtained by reacting with two or more types, to produce goethite particles. Can be obtained. As the ferrous salt, ferrous acetate,
Ferrous oxalate, ferrous sulfate, etc. can be used. It is preferable to use one that does not contain phosphorus, sulfur or the like that can be a catalyst poison such as ferrous acetate and ferrous oxalate. As the alkali hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide or the like can be used. As the alkali carbonate, sodium carbonate, potassium carbonate or the like can be used.

The hematite powder, which is an oxide containing iron as a main component and containing the elements obtained as described above, is
For example, the goethite powder is about 200 to 800 in air.
It can be obtained by performing heat dehydration and heat treatment in a temperature range of ° C, and the magnetite powder is obtained, for example, by heating and reducing the hematite powder at about 300 to 600 ° C in a reducing atmosphere. Furthermore, the maghemite powder can be obtained, for example, by heating and oxidizing the above magnate powder in air at about 200 to 600 ° C.

The above-mentioned iron-based oxide, hydrous oxide, inorganic salt or organic acid salt is heated and reduced.
As the reduction method, a known method may be used, and a method of reducing in a gas phase with a reducing gas, a method of wet reduction and the like can be mentioned, and a method of wet reduction is preferable. As the reducing gas used in the method of reducing in the gas phase,
Examples of the gas include hydrogen gas or a mixed gas of hydrogen gas and an inert gas (nitrogen, argon, helium, etc.). Also,
The heat reduction device used for heat reduction is a fluidized bed reduction device that heats and reduces the starting material while flowing it in powder form, and a fixed bed reduction that granulates the starting material into granules to form a fixed bed and heat reduces. An apparatus, a moving bed reducing apparatus for moving a layer having a fixed bed formed thereon, and the like are known, and any of them may be used in the present invention, but a fixed bed reducing apparatus or a moving bed reducing apparatus is preferably used.

Before the heat reduction treatment, a compound of a specific element may be added in advance so as to segregate near the surface for the purpose of preventing sintering during reduction or maintaining the shape. Specifically, a transition metal element other than iron, preferably Co or N
It is preferable to add i so that it is segregated near the surface. As a method of adding a transition metal element, preferably Co or Ni so as to segregate near the surface, for example,
A solution of a water-soluble salt of a transition metal element to be deposited on the alkaline slurry of the raw material metal powder before the heat reduction treatment is added, and after the hydroxide is precipitated, an appropriate post-treatment (for example,
A method of performing reflux of slurry or heat treatment of dry powder) can be mentioned. Further, examples of the compound added so as to segregate near the surface include compounds containing Si, Al, Zr, or the like, or phenol resin, furan resin, and the like.

The method of forming an oxide film on the surface of the fine metal material obtained by heat reduction may be a known method. A method of suspending a fine metal material in a solution and blowing an oxygen-containing gas (for example, JP-A-60-128202, JP-A-59-16904, JP-A-55-164001).
No.), a fine metal material is gradually oxidized by a diluted oxygen gas to gradually increase the oxygen concentration as the oxide film is formed (for example, JP-A-61-216306 and JP-A-46-46306).
7153) and the like. Further, a method of contacting a fine metal material with carbon dioxide gas at about 250 to 450 ° C. (JP-A-2-303006) and the like can also be mentioned. At this time, the carbon dioxide gas may be mixed with an inert gas, but the carbon dioxide gas concentration is preferably about 10% by volume or more. The contact time between the fine metal material and carbon dioxide is about 3
It is about 0 minutes to 20 hours.

The particles used in the present invention described above may be metallic magnetic particles contained in the magnetic recording medium or the magnetic coating material. As a method of verifying the effect, there is a method of incinerating an actual waste material of the magnetic recording medium. Furthermore, it can be carried out by adding the waste material of the magnetic recording medium containing the above-mentioned metal magnetic particles to an organic waste containing a halogen (chlorine, bromine) element and incinerating it. Then, as a concrete implementation method, a cut piece obtained by finely cutting a waste material of a magnetic recording medium using the above-mentioned sheet-shaped metal magnetic particles is used as an organic waste containing the above halogen (chlorine, bromine) element. It can be carried out by adding it to a product and incinerating it. A more specific method for implementing the above method is to use the waste material of the magnetic paint produced in the manufacturing process of the magnetic recording medium using the metal magnetic particles. That is, it can be carried out by adding the paint to be discarded to the organic waste containing the above halogen (chlorine, bromine) element and incinerating it. In this case, the magnetic coating material can be added to the organic waste as it is and incinerated. Further, it can be carried out by adding the dried product of the magnetic coating material to the organic waste, preferably by crushing the dried product and adding the dried product. Furthermore, it can be carried out by impregnating and drying the above magnetic coating material in organic waste, adding it, and incinerating it.

By the above verification, the present inventors have
(A) The average particle size is about 0.01 to 5.0 μm, (b) the fine metal material mainly containing iron is coated with a metal oxide layer, and (c) the average iron content of the particles. Valence n + is 0
It has been found that a waste material of a magnetic recording medium or a magnetic coating material containing particles with <n <2.5 or a processed material thereof can suppress the production of dioquincins when incinerating an organic waste. That is, the present invention also provides an organic waste incineration catalyst characterized by containing a waste material of a magnetic recording medium or a magnetic coating material containing particles satisfying the requirements (a) to (c) or a treated product thereof. provide.

The magnetic recording medium or magnetic coating material used in the present invention has (a) an average particle size of about 0.01 to 5.0 μm.
And (b) a fine metal material mainly composed of iron is coated with a metal oxide layer, and (c) particles having an average valence n + of iron of about 0 <n <2.5. The shape, structure, composition or the like is not limited as long as it contains. It may be in the form of a product such as an audio tape or a video tape, or may be in a state before it is made into a product. Particularly in the present invention, it is preferable to use a waste material of a magnetic recording medium or a magnetic paint from the viewpoint of effective use of resources. As the waste material, not only used products, but also scraps, scraps, and the like discharged in the manufacturing plant may be used.

Examples of the magnetic recording medium or magnetic coating material used in the present invention include those obtained by subjecting the magnetic recording medium or magnetic coating material to any treatment. Examples thereof include finely cut magnetic recording media, dried magnetic paints, and pulverized dried magnetic paints.

Further, since the magnetic recording medium basically has a structure including a magnetic layer composed of magnetic particles for carrying out magnetic recording and a base material for mechanically holding the magnetic layer, the above-mentioned book is used. The processed product of the magnetic recording medium used in the present invention may be a magnetic layer separated from the substrate or a dried product or a pulverized product thereof. As a method for separating the magnetic layer and the base material in the magnetic recording medium, a conventionally known technique can be used. As a method of separating the base material and the magnetic layer of the magnetic recording medium, specifically, the magnetic recording medium is cut,
Immerse in alkali, swell, separate by stirring at high speed,
A method of separating the base material and the magnetic layer by washing with water, drying and magnetically sorting can be mentioned. More specifically, JP-A-53-70404 and JP-A-59-52433.
The methods described in JP-A No. 59-91028 and JP-A No. 59-91028 may be used. Further, for example, Japanese Patent Laid-Open No. 11-167716
Modifications of the above methods, such as those described in the publication, may be used. In addition, a method of separating the base material and the magnetic layer by using a special organic solvent instead of the alkali can be mentioned. More specifically, a method of peeling a substrate with a pyrrolidone or γ-butyrolactone solution (JP-A-6-18).
No. 0842). Furthermore, for a magnetic recording medium in which an undercoat layer is provided between the base material and the magnetic layer, the material forming the undercoat layer should be dispersed using an organic solvent that dissolves or swells and a dispersion medium. The base material and the magnetic layer can be separated by the method (Japanese Patent Laid-Open No. 5-27).
4666). Examples of the organic solvent that dissolves or swells the material forming the undercoat layer include, for example, a ketone solvent, an ester solvent, an ether solvent, an aromatic hydrocarbon solvent,
Examples thereof include chlorinated hydrocarbons, and among them, a ketone-based organic solvent, particularly methyl ethyl ketone (MEK) or cyclohexanone is preferable. Examples of the dispersion medium include glass beads, zirconia, steel balls and the like. The above method, more specifically, the organic solvent,
There is a method of dispersing a dispersion medium and a cut product of a magnetic recording medium by using a disperser known per se.

The organic waste incineration method according to the present invention has the above-mentioned (i) average particle size of about 0.01 to 5.0.
a particle of about μm, in which a fine metal material mainly containing iron is coated with a metal oxide layer, and the average valence number n + of iron in the particle is 0 <n <2.5, or ( ii) The present invention is characterized in that a magnetic recording medium containing the particles of the above (i) or a waste material of a magnetic paint, or a processed material thereof is interposed. Hereinafter, the above (i) and (ii) are collectively referred to as "organic waste incineration catalyst". There is no particular limitation on the method of incinerating the organic waste through the catalyst for incinerating the organic waste, and a known method may be used. For example, in a gas phase in an incinerator, an organic waste incineration catalyst is spray-added in a powder or slurry state, or a synthetic resin composition prepared by kneading an organic waste incineration catalyst in a synthetic resin in advance is used. The method of putting it in an incinerator can be mentioned. In particular, direct spray addition in the form of powder or slurry to the gas phase in the incinerator is preferable because the combustion catalyst activity can be exhibited more effectively.

When the synthetic resin composition is put into an incinerator, a thermoplastic resin such as polyethylene, polypropylene, vinyl chloride resin, polyester resin, polystyrene, nylon, polyurethane or acrylic resin; phenol resin, urea resin, Synthetic resin such as thermosetting resin such as epoxy resin or unsaturated polyester resin, preferably thermoplastic resin, particularly preferably low density polyethylene, linear low density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, etc. Use a mixture of a polyethylene resin, a polyolefin resin such as polypropylene, etc., with an organic waste incineration catalyst in advance using a mixing roll, Banbury mixer, kneader, twin-screw kneading extruder, etc. You can At this time, the organic waste incineration catalyst can be used by surface-treating the particle surface with various surface treating agents for the purpose of improving dispersibility in the synthetic resin.

In the incineration method according to the present invention, the addition amount of the organic waste incineration catalyst is not particularly limited, but the addition amount of the particles of (i) (the above-mentioned (ii) as the organic waste incineration catalyst is When used, the addition amount of the particles of (i) contained therein is preferably about 0.01 to 5.0 with respect to the organic waste (dry weight) to be incinerated.
% By weight, more preferably about 0.05-3.0% by weight
%, More preferably about 0.1 to 1.0% by weight. In order to obtain a sufficient catalytic effect and to prevent the amount of the residue from becoming excessive due to the large amount of addition, and also from the viewpoint of economy, the amount added is preferably within the above range.

In the incineration method according to the present invention, it is preferable to use a new organic waste incineration catalyst for each incineration. That is, the organic waste incineration catalyst is preferably used once and then discarded together with the incineration residue, rather than repeatedly used. This is because the excellent incineration promoting effect and dioxin formation suppressing effect of the organic waste incineration catalyst as described above become maximum in the first incineration process.

The organic waste to be incinerated in the incineration method according to the present invention is not particularly limited, and even if it is municipal waste,
It may be industrial waste such as waste plastic. In particular, it is preferable to use the method according to the present invention when incinerating an organic waste containing a halogen (among others, chlorine or bromine) element, since the effect of the present invention that the production of dioxins can be suppressed can be exhibited.

The incinerator used in the incineration method according to the present invention is not particularly limited and may be any of a mechanized batch furnace, a fixed batch furnace, a quasi-continuous furnace and a fully continuous furnace. In particular,
In intermittent operation type incinerators such as mechanized batch furnaces and quasi-continuous furnaces, generation of dioxins during low temperature combustion at startup and shutdown is considered a problem, but incineration using such incinerators is also a problem. The present invention can be applied.

By the incineration method according to the present invention, dioxins in the combustion exhaust gas can be treated with about 10 ngTEQ / Nm ³ or less, preferably about 8.0 ngTEQ / Nm ³ or less, more preferably about 6.0 ngTEQ / Nm ³ or less. It can be about 4.0 ng TEQ / Nm ³ or less. In addition, the analysis of dioxins in combustion exhaust gas is measured by the method approved by the Waste Research Foundation.

[0033]

EXAMPLES Next, examples of the present invention and comparative examples will be given, but the present invention is not limited thereto. In the examples and the comparative examples, the incineration method and the analysis method of the samples were the following samples in accordance with JIS K7217B and JIS K0311.

Example 1 An examination was carried out using a magnetic recording medium of metal magnetic particles produced as described below. First, a magnetic paint having the following composition was prepared.

[Table 1]

In the table, the specific surface area was measured according to the BET method. The average major axis length and the average particle size were obtained by calculating the average value of the numerical values measured from electron micrographs. The coercive force and the saturation magnetization were measured with a VSM (sample vibration type magnetometer). The n value is obtained by dissolving the particles in a degassed water system with a non-oxidizing acid,
Amount of hydrogen produced and Fe ²⁺ , F eluted in the solution
It was calculated from the quantification of e ^{3 +} and Co ²⁺ , and the weight increase accompanying complete oxidation of the particles in an oxidizing atmosphere.

This composition was mixed in a ball mill for 48 hours, 3.5 parts by weight of a polyisocyanate curing agent was added, and the mixture was further mixed for 30 minutes, and this was dried on a polyethylene terephthalate film having a thickness of 7 μm to give a thickness of 2 μm.
Was applied and dried. On the other hand, a paint for the back coat having the following composition was prepared.

[0037]

[Table 2]

This composition was mixed in a ball mill for 10 hours, and then 30 parts by weight of a polyisocyanate curing agent was added,
After mixing for another 30 minutes, this is coated and dried on the back surface of the film on which the magnetic layer has been formed so that the thickness after drying is 0.8 μm, and the mixture is placed in an oven at 60 ° C. to accelerate curing.
It was left for 0 hours. Then, calendering was performed, and the film was left in an oven at 60 ° C. for 20 hours to accelerate curing. This was cut into a width of 8 mm and incorporated into a cassette shell for 8 mm to complete a cartridge. This sample was incinerated according to the method described above, and the produced dioxins were analyzed. The total chlorine content of the sample was 0.84% by weight.
The amount of dioxins produced was below the detection limit, the amount of dibenzofurans produced was 0.55 ng / g, and the toxicity equivalent was below the calculation.

[Comparative Example 1] An examination was carried out using a magnetic recording medium of metal oxide magnetic particles produced as follows. First,
A magnetic paint having the following composition was prepared.

[Table 3] The values in the table were measured exactly as in the above table.

This composition was mixed in a ball mill for 48 hours, 3.5 parts by weight of a polyisocyanate curing agent was added, and the mixture was further mixed for 30 minutes. This was dried on a polyethylene terephthalate film having a thickness of 7 μm and a thickness after drying of 2 μm.
Was applied and dried. Then, a back coat layer was formed under the same conditions as in Example 1 by using the same paint as in Example 1. Then, calendering was performed, and the film was left in an oven at 60 ° C. for 20 hours to accelerate curing. this,
It was cut to a 1/2 inch width and assembled into a VHS cassette shell to complete a cartridge. This sample was incinerated according to the method described above, and the produced dioxins were analyzed. The total chlorine content of the sample was 0.35% by weight. The amount of dioxins produced was 0.4 ng / g, the amount of dibenzofurans produced was 0.18 ng / g, and the toxicity equivalent was 0.002 ng-TEQ / g.

Example 2 A waste material of a magnetic recording medium using the magnetic metal particles of Example 1 and a waste material of a magnetic recording medium using the magnetic metal oxide particles of Comparative Example 1 were sampled at the same weight, and Were mixed, incinerated and analyzed. This sample was incinerated according to the method described above, and the produced dioxins were analyzed. The total chlorine content of the sample was 0.60% by weight. The amount of dioxins produced was 0.1 ng / g, the amount of dibenzofurans produced was 0.22 ng / g, and the toxicity equivalent was 0.001 ng-TEQ / g.

Comparative Example 2 The cast film of the vinyl chloride copolymer used in Example 1 and Comparative Example 1 was analyzed. This sample was incinerated according to the method described above, and the produced dioxins were analyzed. The total chlorine content of the sample is
It was 49% by weight. The amount of dioxins produced is 8.8.
ng / g, the production amount of dibenzofurans is 1600
ng / g, and the toxicity equivalent was 20 ng-TEQ / g.

Example 3 The same amount of polyvinyl chloride as the waste material of the magnetic recording medium using the magnetic metal particles of Example 1 was sampled, mixed and incinerated for analysis. This sample was incinerated according to the method described above, and the produced dioxins were analyzed. The total chlorine content of the sample is 24% by weight
Met. The amount of dioxins produced was 2.6 ng / g, the amount of dibenzofurans produced was 37 ng / g, and the toxicity equivalent was 0.51 ng-TEQ / g.

[0044]

EFFECTS OF THE INVENTION The present invention provides a more effective combustion technique for reducing dioxins, in which fine metal materials composed mainly of iron are coated with a metal oxide layer,
By adding to the organic waste containing the halogen element to be incinerated, it is possible to accelerate the oxidative incineration and suppress the production of the organic cyclic compound having the halogen element. Thereby, generation of dioxins due to incineration can be suppressed.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B09B 3/00 303Z (72) Inventor Haruo Watanabe 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony stock In-house F-term (reference) 3K065 AA24 AB01 AC01 BA04 CA04 4D004 AA21 BA06 CA28 DA03 DA10 DA20 4G069 AA03 BA36A BB02A BB02B BC66A BC66B BC67A BC67B CA04 CA07 EA01X EA01Y EB18X EB18Y EC02 EC03Y FC03 EC03Y EC03 FC02

Claims (14)

[Claims] 1. An iron-based fine metal material having an average particle diameter of 0.01 to 5.0 μm coated with a metal oxide layer, wherein the iron has an average valence n + of 0 <. n <2.
An incineration method, characterized in that the organic waste is incinerated through the interposition of particles (5). 2. The composition ratio of iron to the total metal elements in the particles is 60% by weight or more.
Incineration method described in. 3. The specific surface area of the particles is 0.5 to ²⁰⁰ m ^2.
It is / g, The incineration method of Claim 1 characterized by the above-mentioned. 4. The particles are metallic magnetic particles contained in a magnetic recording medium or a magnetic paint.
Incineration method described in. 5. An iron-based fine metal material having an average particle diameter of 0.01 to 5.0 μm and coated with a metal oxide layer, wherein the average iron valence number n + of the particles is 0 <. n <2.
An incineration method comprising incinerating an organic waste by interposing a waste material of a magnetic recording medium or a magnetic coating material containing particles of 5, or a processed material thereof. 6. The composition ratio of iron to the total metal elements in the particles is 60% by weight or more.
Incineration method described in. 7. The specific surface area of the particles is 0.5 to ²⁰⁰ m ^2.
It is / g, The incineration method of Claim 5 characterized by the above-mentioned. 8. A fine metal material mainly composed of iron is coated with a metal oxide layer, and the average valence n + of iron is 0 <n.
A particulate organic waste incineration catalyst having an average particle size of 0.01 to 5.0 μm, which is <2.5. 9. The catalyst for incinerating organic waste according to claim 8, wherein the composition ratio of iron to the total metal elements is 60% by weight or more. 10. A specific surface area of 0.5 to ²⁰⁰ m ² / g
The catalyst for incineration of organic waste according to claim 8, wherein 11. The catalyst for incineration of organic waste according to claim 8, which is metal magnetic particles contained in a magnetic recording medium or a magnetic paint. 12. A fine metal material composed mainly of iron is coated with a metal oxide layer, and the average valence n + of iron is 0 <.
An organic waste incineration catalyst containing a waste material of a magnetic recording medium or a magnetic paint containing particles having an average particle diameter of 0.01 to 5.0 μm with n <2.5, or a treated product thereof. 13. The catalyst for incinerating organic waste according to claim 12, wherein the composition ratio of iron to the total metal elements in the particles is 60% by weight or more. 14. The specific surface area of the particles is 0.5 to 200 m.
^The catalyst for incinerating organic waste according to claim 12, wherein the catalyst is ² / g.