JP2000005730A - Treatment for detoxifying/recycling of incinerate ash and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a recycled product of incinerate ash that no dioxin is detected by analysis and eluation of heavy metals can be prevented in hydrolyzing reaction by accelerated test under an strongly acidic environment by a method hardly causing environmental pollution. SOLUTION: In a treatment for detoxifying/recycling of incinerate ash, a stage in which raw ash is treated by keeping in a space in a low oxygen state insulated from the air at a fixed temp. for a fixed time and generated exhaust gas is catalytically heat treated is provided and the gas is heated in the presence of a transition metal catalyst. A method is composed of a reducing reaction stage and a stabilizing reaction stage. The exhaust gas is subjected to the detoxifying treatment at a reducing reaction stage. The incinerate ash to be treated is pulverized to particulates of 100-150 mesh before a stabilizing reaction stage and/or the reducing reaction stage. The reducing reaction stage is kept at about 400-600 deg.C for 20-40 min. The stabilizing reaction stage is kept at about 200-450 deg.C for 40-60 min. The device is composed of a reducing reaction device, a stabilizing reaction device and an exhaust gas treating device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an incineration ash for effectively utilizing general incineration ash (fly ash, main ash) in a safe form while detoxifying generated exhaust gas from the viewpoint of environmental pollution. The present invention relates to a processing method and an apparatus therefor.

[0002]

2. Description of the Related Art In the last decade, the problem of increasing, treating and disposing of garbage from homes and offices and industrial waste discharged from business establishments in Japan has been discussed in various places. In response to these issues, the "Waste Disposal and Public Cleansing Law" was amended, requiring each and every citizen to reduce and separate garbage, and the "Law Concerning the Promotion of Use of Recyclable Resources" was enacted. Was asked to make effective use of renewable resources in garbage. However, the amount of garbage in the whole country has continued to increase since then, and environmental pollution has emerged from illegally dumped garbage. Recently, the fact that dioxin, a carcinogenic substance, is contained in incinerated ash actually occurred, and urgent measures were urgently needed.

At a garbage incineration plant, a considerable amount of incineration ash after incineration and minute ash (fly ash) generated by cooling the combustion gas and dust collected by a dust collector installed to prevent air pollution. Also occurs. These ashes are called incineration residues, and are new garbage generated by incineration of garbage. 70 incineration residues generated at incineration plants nationwide during the year
It has reached 10,000 tons and will be landfilled at the final disposal site. The meaning of weight reduction by incineration is to throw it into the atmosphere. A substance exists in one of three forms: solid, liquid, and gas. When the solid material disappears,
Instead of disappearing, it turned into a gas. Before the residue is dust, which is 10 to 20 times the amount of the residue. If the landfill is filled as it is, it will fill the landfill in 5 to 10 years, and the whole of Japan will be turned into a hill of garbage. Therefore, in order to extend the life of the landfill even a little, it is necessary to recycle what can be recycled. However, incinerated ash cannot be used as it is.

[0004] Even incineration ash burned under the best conditions is oxidized by being burned, and the garbage contains a large amount of chlorine-containing plastics such as vinyl chloride. Therefore, incineration may result in compounds containing high concentrations of chlorine. This is the problem of dioxins. In 1983, poisonous dioxin 2.3.7 from incineration ash from waste incineration plants in 7 cities in Japan
・ 8TCDD has been detected. This type is by far the most toxic of dioxins, and 50
It is said to be 00 times. Although the mechanism of the generation of dioxin is not clear, the theory that organochlorine compounds (such as vinyl chloride) were generated by thermal decomposition as a result of incomplete combustion at a temperature of about 300 to 600 ° C, It is also thought to be the catalytic action of the generated hydrogen chloride. What is made of an incinerator that burns a myriad of organic chemicals together with plastics such as vinyl chloride, various dyes, and chlorobenzenes such as insect repellents in such municipal waste. It can be said that it is a chemical synthesis plant that you do not know. Substances change shape in various ways due to chemical reactions associated with combustion. That is, even if the combustion technology of garbage incineration processing that produces harmful chemical substances such as dioxin can be improved to suppress the generation of dioxin itself, the second and third problems cannot be prevented.

[0005] In order to solve these problems fundamentally, what is the composition of the garbage in the furnace,
One must know what is created as a reaction product. Another is to convert the generated incineration ash to a more stable substance. It is impossible to replace existing incinerators immediately or eliminate them. What is safe, stable and reassuring is that this residue is treated once more, the treated residue passes the dissolution test and the measured value of dioxin is zero. Landfilling this ash as it is will be a power to change the earth's environment as a result of carbon dioxide and exhaust heat 10 or 20 years later, and the remaining ash will dissolve in water, causing pollution.

[0006] The original form of the garbage that has been turned into ash is anything that is absolutely necessary for daily life, such as paper, wood, garbage, plastic and metal compounds. The raw materials used as the basis for these materials have been digged out of the earth's crust by human beings, refined to make metals, and made substances, so this raw material has existed on Earth for hundreds of thousands of years as a stable substance. It is. It should be returned to Earth in the state of the compound at that time. Burning it in an incinerator to fill it with metal oxides or metal chlorides is not possible because it imposes too much on nature. Bridging this is not just a matter of the direct destruction of crushing lush valleys. It is safe if the ash buried in the earth becomes a substance that does not dissolve in water. Most naturally occurring substances are poorly soluble in water, ie, poorly soluble compounds. I have to change to such a compound.

Most of the general incinerated ash (fly ash and main ash) of city garbage is ultimately landfilled. These are expected to undergo various changes due to wastes coexisting in the process of eroding rainwater and seawater, and that dioxins contained in heavy metals and fly ash flow out together with leaching water. For heavy metals, oxides are chlorides and relatively water-soluble metal compounds.Dioxin is not a water-soluble substance, but it is treated from the viewpoint of environmental pollution when it gradually dissolves in water. It is necessary to establish a method.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a safe cement-based material which does not pollute the environment with heavy metals and dioxins from municipal garbage incineration ash while detoxifying the generated exhaust gas. It is an object of the present invention to provide a method and an apparatus for treating incinerated ash for producing ash. The present invention relates to incinerated ash reclaimed material (cement-based material) that is not detected by dioxin analysis in incinerated ash recycle, and that can prevent elution of heavy metals by an accelerated test in a strongly acidic environment by a hydration reaction. ) Is to be provided by a method and an apparatus for producing the same without environmental pollution.

[0009]

DISCLOSURE OF THE INVENTION The present invention is intended to detoxify and recycle incinerated ash which maintains raw ash, which is incinerated ash, in a low-oxygen space insulated from the outside air at a constant temperature and for a fixed time. In the treatment, the raw ash is dried to reduce the water content, and a drying process for thermally decomposing dioxins in the exhaust gas, and a pulverizing process for expanding the dried ash to increase the surface area. The gist is a method for treating incinerated ash, which is provided. In the above-described process of maintaining a constant temperature and a constant time in a space in a low oxygen state insulated from the outside air, a smoke exhaust treatment process can be attached.

Further, the step of performing the treatment while maintaining a constant temperature and a constant time in the low-oxygen state space insulated from the outside air includes a reduction reaction treatment step and a stabilization reaction treatment step. That is, a reduction reaction treatment mainly comprising a decomposition reaction of dioxins and a reduction reaction of heavy metal oxides and a stabilization reaction treatment mainly comprising an insolubilization reaction of heavy metals (that is, the stabilization herein means the reaction treatment). The ash undergoes a hydration reaction to stabilize and solidify the ash, so that the elution of heavy metals is prevented.). The above-mentioned drying treatment step and the drying treatment step are preferably provided before the reduction reaction treatment step is started. In the drying process, the furnace is heated to a temperature of 800 to 900 ° C. while introducing nitrogen gas. Here, the raw ash (unburned incinerated ash) is completely burned,
In addition, the exhaust gas therefrom is detoxified. Nitrogen gas is mixed with the generated exhaust gas, and the mixed gas is heated, and preferably, the mixed gas is heated in the presence of a catalyst to detoxify the exhaust gas. . In the above pulverization process, 10
Pulverize into fine particles of 0 to 150 mesh. In the above reduction reaction treatment step, the incineration ash temperature is about 400 ° C. to 60 ° C.
Maintain at 0 ° C. for a time of 20-40 minutes. In the stabilization reaction treatment step, the treatment temperature is raised to 200 ° C. to 450 ° C. for 4 hours.
Hold for 0-60 minutes.

The present invention also relates to an apparatus for carrying out the above method, which comprises a drying apparatus, a pulverizing apparatus, a reducing reaction apparatus and a stabilizing apparatus. The device is the gist. A flue gas treatment device can be attached to each of the reduction reaction treatment device and the stabilization reaction treatment device. Further, the same apparatus can be used for the drying processing apparatus and the reduction reaction processing apparatus. Further, it is preferable to provide a means for mixing and circulating nitrogen gas.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method of the present invention, all incinerated ash generated after incineration of general waste, such as bottom ash or a mixed ash of bottom ash and fly ash, can be used as raw ash. Raw ash, such as the incineration ash of general waste, often contains unburned carbon, hydrocarbons, etc. due to the low temperature of incineration. Moreover, harmful dioxins such as polychlorinated dibenzoparadioxin and polychlorinated dibenzofuran of tetrachloride to octachloride are contained in the incineration fly ash collected by various dust collectors in the incineration facility. Furthermore, general waste incineration ash contains calcium carbonate and calcium silicate compounds,
Although it is known that the vitrification component is high, it has been reported that it sometimes contains harmful heavy metals. In the method of the present invention, incinerated ash containing harmful heavy metals and dioxins together with unburned carbon and hydrocarbons can be used as raw ash. Since raw ash contains many impurities, it is used after sieving by particle size and iron removal.

<< Necessity of Low-Temperature Treatment >> The present invention employs a treatment method in which heavy metals and dioxins in incinerated ash are treated at a low temperature. Environmental issues should be integrated with economic issues. In particular, incinerated ash and the like are burnt ash that is used in daily life and left as ash, which has emerged as new garbage. It is good to change to a property that does not dissolve, and it would be good if the environmental problem could be solved in an easy, safe, and stable manner. The fact that incinerated ash is melted at high temperature and vaporized at high equipment costs and high running costs
It is becoming more difficult to bury it in the basement, so it will be turned into a dumping site for the atmosphere. And these substances have their own properties, and it is inevitable that they will come up from the atmosphere as problems that cannot be solved again. It is important to make "incinerated ash" a "naturally compatible substance" with no dangerous substances by using a small amount of heat and a small amount of catalyst to cause a chemical reaction. In addition, the potential for air pollution is steadily increasing. Photochemical smog by atmospheric photochemical reactions causes various reactions and synthesizes many by-products. Radical reactions may occur one after another in the atmosphere, and highly toxic substances may be synthesized in the atmosphere. Burning at such a high temperature to vaporize the substance is not the only processing method. As much as the incinerated ash is reduced as a visible solid, only a small amount of material elements that are not visible as a gas are running around in the atmosphere. This should be the case if the chemical reaction is possible at low temperatures, and one should be interested in this. Environmental issues are an important requirement for the solution by adopting economically inexpensive means. In particular, incinerated ash etc. is the residue left as ash by burning what is used in everyday life and comes out as new garbage.
High costs are not worth it to make something valuable. For example, the melting method of melting incinerated ash and collecting it as slag,
It is necessary to raise the temperature to 1200 ° C. or higher, resulting in high energy costs and enormous capital investment. The processing method performed at a low temperature is firstly superior to the processing method performed at a high temperature in that no equipment cost is required. It should not be a solution that creates another unsolvable problem. Hazardous substances such as cadmium, lead and hexavalent chromium may be contained in raw ash and sewage sludge of general waste, but by incineration at around 900 ° C, preferably around 850 ° C, It can be changed to one with a safe property that does not dissolve in water (for example, trivalent chromium). Employing high temperature processing can create another unsolvable problem. In order to use incinerated ash effectively, harmful substances such as heavy metals have the property of dissolving into the environment, so it is only necessary to change it to a property that does not dissolve in water, and it can be solved by a treatment method performed at low temperature . For example, melting it at a high temperature and vaporizing it at a high facility cost and a high running cost means changing the dump site to the atmosphere, which causes another problem that cannot be solved. The same applies to the problem of dioxin, and it is important to decompose dioxin in raw ash and not to generate new ones.

<< Realization of Low-Temperature Treatment >> By the low-temperature treatment, the water-soluble substance of the incinerated ash is changed to a hardly soluble substance while suppressing the generation of dioxins. It is necessary to convert a water-soluble substance into a hardly soluble substance, but using high temperature and high pressure is not economical. In order to promote the metal reaction by the catalytic action and to facilitate the formation of the substance by the ionic reaction, the reaction surface area is increased by powdering, and the temperature is constant in the deoxygenated space insulated from the outside air such as the reaction atmosphere. And maintain for a certain time. There are a wide variety of substances that can be catalysts, whether gas, liquid, or solid. Since the metal catalyst has a small metal surface area and is inefficient as a catalyst, the metal is used as a fine powder with the surface area being as large as possible. That is, when the incinerated ash containing these catalyst components is pulverized to reduce the particle size and then treated, as a result, the catalyst components also have an increased surface area and a higher catalytic activity. To control the generation and emission reduction of dioxins, the combustion process in the incinerator, the heat recovery from the exhaust port to the exhaust gas treatment device, the gas cooling process, and the removal of air pollutants mainly dust in the exhaust gas treatment device, etc. Is suppressed.

The processing method performed at a low temperature in the present invention is as follows.
This is achieved by using the following principle by increasing the reactivity of the raw ash itself. Chemical analysis of elements existing on the earth up to a depth of 1.6 km in the earth's crust (lithosphere), seawater, inland water and continental ice (hydrosphere), and air (atmosphere) Based on this, the abundance of constituent elements near the surface of the earth is calculated.
Oxygen is the most common and about 4% of all elements
It accounts for 6.6%. Next is 27.7% silicon.
Next, 8.13% of aluminum, these are the main constituent elements of silicate, followed by iron, calcium, sodium, potassium, magnesium, etc. in order of 98.6% of silicate constituent elements. Occupy. Some of these elements are classified according to the periodic table, but other than the periodic table, some elements are classified from the viewpoint of what kind of compounds the elements easily form on the earth. Divided into elements. 1) Litholith elements Elements that collect on the silicate phase in the crust of the lithosphere on the earth (alkali metals such as silicon, aluminum, calcium, sodium, potassium, magnesium, fluorine, chlorine, alkaline earth metals, halogen elements, etc.) 2) Ferrophilic elements Elements that gather in the core of the earth (iron, nickel, cobalt, ruthenium, rhodium, palladium,
Osmium, iridium, platinum, etc. 3) Copper-friendly elements Elements that mainly gather in the sulfide phase on the earth (copper, silver, zinc, cadmium, mercury, lead, arsenic, sulfur, etc.) 4) Air-friendly elements Easily distributed to the atmosphere Element (hydrogen, nitrogen, carbon, oxygen, rare gas, etc.)

In general, a copper-philic element has a higher affinity (bonding force) for sulfur than oxygen in a reducing environment, and a lipophilic element has a higher affinity for oxygen than sulfur. In addition, ferrophilic elements are relatively hard to bond with sulfur and oxygen. These elements create various substances on the earth, but solid inorganic substances that occur naturally are called minerals, and constitute the lithosphere. Among them, simple gold (Au) and diamond (C) are generally rare and rare, but compounds are relatively widely produced on earth, and sulfides, oxides, hydroxides, and sulfuric acids are used. It exists stably in countless compounds such as chloride. In order to produce such stable compounds from incinerated ash, the present invention is carried out using a minimum of thermal power and a small amount of effective catalyst. The incineration ash is made into a fine powder and suspended, and the catalyst is oxidized by a catalytic oxidation reaction on the surface of the catalyst called "catalytic combustion", thereby enabling complete combustion and completing the reaction at a low temperature.

<< Drying by inert gas >> Incineration ash is a mixture of oxides of metal or nonmetal elements. In some cases, toxic substances may be generated. Drying with an inert gas. The treatment is 80 for the decomposition of dioxins.
Although the objective can be sufficiently achieved at a temperature of 0 ° C. or higher,
Considering complete decomposition of dioxins, the treatment temperature is preferably around 900 ° C. in ambient temperature. In the present invention, drying treatment is performed in advance in treating incineration ash. In this drying treatment step, by treating at a furnace temperature of 800 to 900 ° C., the moisture content of the incinerated ash is reduced (2% or less) and the dioxins in the exhaust gas are thermally decomposed. Nitrogen (N2) gas is used as the inert gas, and the gas is circulated. The block flow is as shown in FIG. When nitrogen (N2) gas is used as the inert gas, the molecular weight of nitrogen is 28, and its thermal characteristics (heat capacity, thermal conductivity, heat transfer coefficient, etc.) are almost the same as air having a molecular weight of 29. . Therefore, the drying characteristics remain unchanged. Since stable operation cannot be maintained unless the temperature and humidity of the gas sent from the heater to the drying device are always constant, a heat recovery unit that performs gas heat exchange so that the temperature conditions return to the heater is also constant. Put on.

<< Decomposition of Dioxins >> In the present invention, in the drying treatment step, the decomposition reaction of dioxins is performed by completely burning incinerated ash. For the decomposition of dioxins, the treatment can sufficiently achieve the purpose at a temperature of 800 ° C. or higher. However, in consideration of the complete decomposition of dioxins, the processing temperature is about 900 ° C. in ambient temperature, and the calcination ash temperature is about 600 ° C. C is preferred. Combustion ash discharged from incinerators at general incineration plants contains a large amount of unburned matter, and harmful dioxins are contained in incineration fly ash collected by various dust collectors at incineration facilities. The mechanism of dioxin production is
The reaction of unburned residual carbon, oxygen and chlorides (metal chlorides, etc.) generated from the reaction mechanism and processing equipment depending on the thermodynamics, reaction rate, and electronic state of molecules in the combustion process of incineration of municipal waste. To produce an organic chlorine compound. In the incinerator, incineration of vinyl chloride plastics, CO ₂ , SO ₂
Generation of hydrogen chloride due to the reaction with A large amount of hydrocarbon (C _n H _m) is generated, by contact with O _2, decomposed into CO ₂ and H ₂ O. However, incomplete combustion may produce dioxins and precursors. Compounds with 2 or 4 carbon atoms generated during combustion are chlorinated in a catalytic reaction with chlorine gas and metal chlorides generated from hydrochloric acid and oxygen at high temperatures, and then chlorobenzene through chloroethylene and chloroacetylene compounds. Is generated. Chlorobenzene reacts with hydroxyl radicals (OH.), Oxygen, and other combustion exhaust gases to form chlorophenols and chlorophenoxyl radicals, which combine with compounds having 2 or 4 carbon atoms to form polychloromonobenzdioxins and polychloromono. Benzofuran and even dioxin are produced. In controlling the generation and emission reduction of these dioxins, combustion processes in incinerators, heat recovery from exhaust ports to exhaust gas treatment equipment, gas cooling processes, and removal of air pollutants, mainly dust, in exhaust gas treatment equipment, etc. Is suppressed. The generation of dioxins can be suppressed by complete combustion, and there is no danger of generating dioxins unless incomplete combustion products are generated during the combustion and exhaust gas treatment processes.

In order to completely burn the incinerated ash discharged therefrom, the discharged incinerated ash is further burned to remove incombustible substances, and the temperature of the combustion gas from the combustion kiln is kept constant, and a sufficient gas residence time is maintained. It is necessary to reduce the amount of unburned carbon, hydrocarbons and other substances in the combustion gas by sufficiently stirring the gas in the kiln and mixing with the secondary air. Generally, these dioxins are not completely decomposed at a calcination temperature of 950 ° C. or lower. Firing temperature 9
Together it becomes equal to or larger than 50 ° C. dioxins harmless decomposed, most of the chlorine, calcium chloroaluminate _{(11CaO · 7Al 2 O 3 ·} CaCl 2) and calcium chlorosilicate (2CaO · SiO ₂ · CaCl ₂
3CaO.SiO ₂ .CaCl ₂ ) and the like, fixed as a hydraulic mineral. The present invention can decompose dioxins at an incineration ash temperature lower than the above temperature of about 400 ° C. to 600 ° C. by the action of a catalyst or the like in this reduction reaction treatment. However, the heat treatment of incinerated ash such as fly ash in a low oxygen atmosphere means that heating (250 to 400 ° C.) of fly ash in an oxidizing atmosphere generates dioxin by the catalytic action of various metal compounds. We must consider that they are two sides of the same coin. By heating incineration ash such as fly ash in a low oxygen atmosphere under oxygen deficiency, dioxins in the ash can be dechlorinated and decomposed, and dioxins in the treatment equipment can also be thermally decomposed. . In an oxidizing atmosphere, dioxins react with precursors, such as chlorides and carbon in fly ash, and are generated in large quantities at around 300 ° C. However, when heated to an atmosphere temperature of 450 ° C or more in a reducing atmosphere, the catalyst becomes a catalyst. Dioxins are decomposed by the action. In the present invention, in order to eliminate the generation of dioxins in the process of low-temperature treatment, the unburned substances are completely burned before the treatment, the contained dioxins are completely decomposed, and the exhaust gas is converted into nitrogen gas. Characterized in that it is completely decomposed so as not to generate dioxins by heat treatment in the presence of. By performing fly ash heating in a low oxygen atmosphere under oxygen deficiency, dechlorination / hydrogenation of dioxins can be achieved.

<< Adoption of reduction treatment reaction >> The incinerated ash is made into fine particles to increase the surface area, and then put into a combustion kiln in a reduced oxygen atmosphere. The chemical reaction in the kiln is a catalytic reaction, in which the free energy is reduced, the reaction rate is increased, radicals are generated, and the radicals are diffused into the gas phase by a chain mechanism to accelerate the reaction.
The reaction of radicals such as CaO, K ₂ O, Al ₂ O ₃ , and SiO _{2 with the} reaction gas due to adsorption on the solid surface and temperature change, and synthesis of a substance having a catalytic function on the surface enables the formation of a catalyst with a high active point. Become. The main reactions of the reduction treatment are dechlorination of organic chlorine compounds and decomposition of dioxins in ash,
Thermal decomposition of organic chlorine compounds, decomposition of dioxins in the furnace,
Reduction of heavy metal oxides and activation of heavy metals. In an oxidizing atmosphere, a large amount of dioxins are generated from precursor materials at around 300 ° C. using chlorides and carbon in fly ash as catalysts, but can be decomposed by a catalytic action when heated to 450 ° C. or more in a reducing atmosphere. First, a dehydrochlorination reaction occurs, followed by reduction, resulting in a dechlorination / hydrogenation process. Ammonia (NH ₃ ) is discharged from this dry distillation state, and NO _x can be suppressed by its reducing power. At the same time, a stabilization treatment for heavy metals is performed.

<< Utilization of Catalyst Function >> Although there is no particular limitation on the catalyst used in the present invention, the main component of the raw material of the catalyst (carrier) is a fine powder of treated combustion ash. Cement-like fine powder contains Na,
Mg, Al, Si, P, S, Cl, K, Ca, Ti,
V, Cr, Mn, Fe, Cu, Zn, Pb, etc. are present as oxides. A mixture of oxides of these elements in lime aluminate 3% to 5%, Portland cement 2
5% to 27% is added, dry-mixed first, water necessary for molding, an inorganic solidifying agent is added as a molding aid, and sufficiently wet-kneaded to form a desired shape (see a heat storage tower shown in FIG. 5). Perform curing and curing. Any shape such as a pellet, a plate, a cylinder, a lattice, and a honeycomb can be used. Further, the present catalyst is extremely excellent in mechanical properties and physical properties, and can stably withstand long-term use. A precious metal catalyst substance such as Pt and, if necessary, Mn, Cu, Cr, Fe, etc., are supported as a metal or an oxide thereof on the molded product obtained as described above to obtain a product catalyst. The features of the catalyst support described above are themselves active, so that a catalyst with the desired level of performance can be obtained with a minimal loading. In particular, when a large amount of catalyst is prepared, these advantages are advantageously exhibited. White metal treatment is 0.5 l / l
g to 1.0 g applied to the surface. The composition supporting the platinum compound is dried at 70 to 170 ° C. and then calcined in air at 400 to 600 ° C.
Reduction treatment is performed at 250 to 500 ° C. in hydrogen-nitrogen gas. In addition, instead of the air heating treatment, the hydrogen gas treatment, and the hydrogen-nitrogen gas treatment, a product can be obtained by treating and activating the exhaust gas to be treated. It goes without saying that the production method is not limited to these. The type of the reactor is not particularly limited, but a usual fixed bed, moving bed, fluidized bed, or other reactor can be used. The method of the present invention is an exhaust gas treatment method for removing polychlorinated dibenzodioxin or polychlorinated dibenzofuran contained in incinerator exhaust gas or the like by using the catalyst. Costs and equipment costs can be reduced. In the present invention, a reduction reaction treatment mainly comprising a decomposition reaction of dioxins and a reduction reaction of oxidized heavy metals is performed. The components of general waste incineration ash are:
It is mainly silicon and calcium, and also contains metal oxides such as aluminum and iron. And
As for the harmful heavy metals that have recently become a problem, lead is high,
Next is mercury and cadmium. Another characteristic is that it contains a lot of chlorine. The incorporation of these heavy metals hinders the promotion of effective utilization of incineration ash. It is difficult to theoretically elucidate the reaction mechanism of the reduction catalyst, and by using various additives and / or catalysts to evaluate the elution of heavy metals from the product by trial and error, the reduction reaction of oxidized heavy metals and the heavy metals A technology has been established for the use of phenol as a reduction catalyst and / or for chemically reacting it with a stable compound. Catalysts include metal catalysts and metal oxide catalysts. Among the metal elements, transition metals such as iron, cobalt, nickel, copper, and ruthenium, rhodium, palladium, osmium, iridium, and platinum, which dissociate hydrogen molecules, turn into hydrogen atoms to increase activation. Normally, the energy to dissociate hydrogen molecule is about 4
The hydrogen atoms are not dissociated without the energy of 50 kJ, but the hydrogen atoms are easily dissociated at room temperature on the surface of Ni, Pd, Pt, etc., and adsorb on Ni, Pd, Pt. The driving force for this dissociation is the chemical affinity for hydrogen atoms on the metal surface. The dissociated hydrogen atoms are highly reactive and are added to hydrocarbons (such as ethylene and propylene) approaching the metal surface or to organic compounds such as compounds of carbon and oxygen to form hydrogenation products. Also, white metal, Fe,
Co and Ni also dissociate the C—H bond of the hydrocarbon and also perform hydrocracking. Thus, the catalyst has the power to convert metal molecules into active metal atoms and to promote chemical reactions without relying on heat sources.

The incineration ash contains many typical elements,
Low in element, transition metals Ti, V, Cr, Mn, Fe,
Cu, Zn, etc. have too strong a bond with oxygen and
Therefore, the amount of oxygen is reduced to 6%. transition
Metal oxides are active in oxidation and active in dehydrogenation.
It is divided into what is shown. Fe_TwoO_Three, Cr_TwoO_ThreeIs a hydrogen molecule
Is not reduced to the metallic state even if
It is a good catalyst for it. Cr in incineration ash is CrO_ThreeThree
Since it is a compound that is easily dissolved in water with chromium oxide, it reacts with hydrogen
It becomes chromium hydroxide and is cheaper due to the combustion process of chromium hydroxide.
It becomes a constant insolubilized dichromium trioxide compound. Typical metal oxidation
The product interacts with the reaction molecule by acid-base,
Or the reactive molecule abstracts a proton by extracting a proton.
Activate. SiO_Two, Al_TwoO_Three, MgO and the like.
The metal catalyst contained in the incineration ash is used for the catalyst particles in the reactor.
The larger the outer surface area, the greater the activity.
The smaller the better. Reactant and catalyst are identical
The reactor type is a fluid type, and the reactants are continuously
And the product is continuously removed. Inside the reactor
Are well agitated and fully mixed streams. Generally, the catalyst
Include metal catalysts and metal oxide catalysts. With transition metal
Certain Fe, Co, Ni, Cu and white metal Ru,
Rh, Pd, Os, Ir and Pt dissociate hydrogen molecules,
Increase the activation by making it a hydrogen atom. Normally dissociates hydrogen molecules
About 450 kilojoules of energy
It is important to note that on surfaces of Ni, Pd, Pt, etc., room temperature
And easily adsorb on Ni, Pd and Pt. this
The driving force for dissociation is the chemistry of hydrogen atoms on metal surfaces
Affinity. Dissociated hydrogen atoms are highly reactive,
Add to hydrocarbons approaching the surface or add carbon and oxygen
Addition to organic compounds such as compounds to produce hydrogenated products
You. In addition, white metal, Fe, Co, and Ni are hydrocarbon C-
Hydrogenolysis is also performed by dissociating H bonds. Like this
The medium transforms metal molecules into active metal atoms, and performs chemical reactions.
It has the power to promote regardless of the heat source. Inside the incineration ash
Has many typical elements and few transition elements. Transition metal
Ti, V, Cr, Mn, Fe, Cu, Zn, etc.
Is too strong to form a metal oxide,
The (combustion) system is a low-oxygen space where the amount of oxygen has been reduced to 6%.
And Transition metal oxides are active in oxidation
And those exhibiting dehydrogenation activity. Fe_TwoO_Three,
Cr_TwoO_ThreeIs reduced to the metallic state even in the presence of hydrogen molecules.
It is a good catalyst for dehydrogenation. In incineration ash
Cr is CrO_ThreeIs a compound that is easily soluble in water.
Cr (OH)_ThreeAnd Cr (OH)_ThreeIn the combustion process
More stable insolubilized Cr_TwoO_ThreeBecomes SiO_Two, Al_TwoO
_ThreeTypical metal oxides, such as MgO and MgO, are reactive
Interact with each other to give a proton to the reactive molecule,
Activate molecules by extracting protons from the molecule. Touch
The medium contains iron oxide (Fe) as a main component._ThreeO_Four), As a co-catalyst
Potassium oxide (K _TwoO) (0.5-1.5%), Al
Mina (Al_TwoO_Three) (2-4%), calcium oxide (Ca
O) (1-3%), silica (SiO_Two) (0.2-1
%), Magnesium oxide (MgO) (0.2-4%)
Which is used. Forming poorly soluble compounds by the action of a catalyst
I do. The main reaction is a sulfidation reaction. Included in incineration ash
The metal catalyst has a large outer surface area of the catalyst particles in the reactor.
As the activity increases, the smaller the catalyst particles, the better.
Because the reactants and catalyst are identical, the reactor type is
The reactants are continuously supplied to the reactor in a fluidized manner, and the products are
It is taken out continuously. The inside of the reactor is sufficiently stirred and
It is a total mixed flow.

<< Enlargement of Surface Area >> The incineration ash subjected to the treatment can be pulverized into fine powder to increase its surface area, thereby increasing its reactivity. First, the grain size is reduced to 10 mesh or less by grain size sorting, iron sorting, or the like, and then charged into a burning kiln under a reduced oxygen atmosphere. Further, the raw ash subjected to the reduction reaction treatment is subjected to 100 to 150 before being subjected to the stabilization reaction treatment.
Make fine powder of mesh. The chemical reaction in the kiln is a catalytic reaction, and the larger the outer surface area of the catalyst particles in the reactor, the greater the activity. Therefore, the smaller the catalyst particles, the better. By pulverizing into a fine powder to increase the surface area, free energy is reduced, the reaction rate is increased, radicals are generated, and the radicals are diffused into the gas phase by a chain mechanism to promote the reaction.
The reaction of radicals such as CaO, K ₂ O, Al ₂ O ₃ , and SiO _{2 with the} reaction gas due to adsorption on the solid surface and temperature change, and synthesis of a substance having a catalytic function on the surface enables the formation of a catalyst with a high active point. Become. In an oxidizing atmosphere, a large amount of dioxins are generated from the precursor material at around 300 ° C. using chlorides and carbon in fly ash as catalysts, but 45
If heated to 0 ° C. or higher, it can be decomposed by catalytic action. First, a dehydrochlorination reaction occurs, followed by a reduction and dechlorination /
It is a process of hydrogenation. Ammonia (NH ₃ ) is discharged from this dry distillation state, and NO _x can be suppressed by its reducing power. At the same time, a stabilization treatment for heavy metals is performed.

<< Stabilization of incineration ash >> The incineration ash, which is a mixture of dissimilar metals containing heavy metals, is efficiently mutually decomposed, and the metal salts are eluted using heavy metal salts as a catalyst, and then crystallized at that time to stabilize. Become That is, the term "stabilization" as used herein means that the reaction-treated ash undergoes a hydration reaction so as to be stabilized and solidified, so that the elution of heavy metals is prevented. The incinerated ash is Na, Mg, Al, Si,
P, S. Cl, K, Ca, Ti, V, Cr, Mn, F
It contains unburned carbon C in addition to the seven elements e, Cu, Zn, P and B, and is a mixture of metals and non-metals. Metals are stabilized as compounds, and depending on the metal species, oxides,
Stabilized by metal compounds such as hydroxides, sulfates, sulfides, phosphorus oxides and phosphides. Hydroxides other than alkali metals and alkaline earth metals are compounds that are hardly soluble in water [C
u (OH) ₂ , Al (OH) ₂ , Zn (OH) ₂ , Pb
(OH) ₂ , Fe (OH) ₂ etc.], As, P, etc.
Reacts with O to become a stable compound. When a metal compound is buried underground, microorganisms in the soil gradually mineralize most of the constituent elements and reduce it to the atmosphere in the form of CO ₂ , H ₂ O, N _2, and the like. In addition, inorganic cations such as Ca ²⁺ , Mg ²⁺ , K ⁺ , and NH ⁴ are adsorbed on humus and clay. In the humus, the functional group as an organic acid adsorbs these cations in the clay due to the interlayer position of the clay mineral or the negative charge of the lattice break. NO
^3-, Cl ^-, anions such as SO ₄ ^2-also adsorbed by partial positive charge of the humus and clay. Most of the stable metal compounds will be present in the internal structure of primary minerals, clay minerals and humus, and will be adsorbed and retained in solution in the form of ions or ion exchange sites on the surface of clay or humus. You. Further, incinerated ash has a high basicity CaO / SiO _{2 and} has a property of being crystallized by slow cooling, and becomes vitreous when rapidly cooled. That is, a stable and safe substance is generated as a substance that is hardly soluble in water. As a reaction, some elements tend to be electrically positive and others tend to be negative, and a stable compound is produced by a combination of yin and yang. Many metal elements are positive elements, and non-metal elements are negative elements. Compounds (salts) produced by the combination are composed of positive and negative components, are single salts, double salts and complex salts. No metals other than precious metals are produced as a single substance. Alkali metals exist as ions in water. Many metals have a tendency to ionize and tend to dissolve in acid solutions. Elements are circulated through rocks, the atmosphere, seawater and metamorphism by solar energy and crustal energy inside the earth, and O, Si, Al,
Mostly made of silicate with Fe, Cu, Na, K, Mg. Other types of compounds, such as halide carbonate, arsenate and borate, all have properties as ionic compounds. For halides, sulfides, and oxides, the negative element alone becomes an anion and is formed by bonding with the cation, and in all other compounds, the negative element is combined with the enzyme to become an oxoacid ion, It is formed by combining with cations. Anion: chloride ion (Cl ^-), sulfide ions
(S ²⁻ ), oxide ion (O ²⁻ ) oxo acid ion: carbonate ion (CO ₃ ²⁻ ), phosphate ion
(PO ₄ ^3- ), hydroxide ion (OH), arsenate ion (ASO
₄ ^{3-), 2-} sulfate ions (SO _4), borate (BO ₃ ^2-),
Nitrate ion (NO ₃ ⁻ ), silicate ion (SIO ₄ ⁴⁻ ) These ions constitute a compound, and the solubility of the cation and anion of this ionic compound is determined by the solubility and Stipulated, S ²⁻ and SO ₄ ²⁻ ,
CO ₃ ^3- reacts with metal ions to form poorly soluble compounds. However, since water is a strong ligand, it is easy to coordinate with metal element ions, and many metal media are immediately converted to aqua media when dissolved in water. To change a water-soluble substance into a poorly soluble substance, the properties of the compound of the substance element are changed. Hazardous heavy metals, which are a hindrance to incineration ash recycling, are stably insolubilized in a low solubility and difficult to elute form. In the present invention, an additive for preventing elution of heavy metals can be added.
As an additive for preventing heavy metal elution, an additive is selected such that the elution thereof is below the detection limit simply by incineration. Incinerated ash is a mixture of metal and non-metal, and the metal is stabilized as a compound. The form of stabilization differs depending on the metal species, and the metal compound is stabilized as a metal compound such as an oxide, a hydroxide, a sulfate, a sulfide, a phosphate, and a phosphide.

<< Product of the Present Invention >> Since incinerated ash generally has a high water content and contains a lot of heavy metals and the like, it is most difficult to solidify it with hydraulic cement. In order to detoxify the metal having the solidification inhibiting factor and promote the hardening of the organic compound, the inhibiting factor is removed by dry distillation and combustion in a reduced oxygen atmosphere. Cement reacts with water to precipitate hydrate crystals, which are connected to each other and solidify, and the hydrate crystals are stable at room temperature. The major component is lime (CaO), followed by silicic acid (SiO ₂ ), whose content is 88% of the total. Then, alumina (Al ₂ O ₃ ), iron (Fe ₂ O ₃ ), sulfate (S
O ₃ ). These chemical components do not simply exist as oxides, but as compounds and react with water to form hydrates. It exists as a so-called hydraulic hard material. For ordinary Portland cement, the mineral that governs its hydration strength is 3Ca, commonly called Alite.
O, SiO ₂ , and 2Ca called Belite
O, SiO ₂ , Alite and Belite 7
Accounts for 6%. Each of these compounds is a compound of lime (CaO) and silicic acid (SiO ₂ ), and forms hydrate crystals by the following reaction upon contact with water. _{2Ca 3 SiO 5 + 6H 2 O} = Ca 3 Si 2 O 7 · 3H 2
_{O + 3Ca (OH) 2 2Ca} 2 Si 4 + 4H 2 O = C
a ₃ Si ₂ O ₇ .3H ₂ O + Ca (OH) ₂ These hydraulic lime silicates differ in the rate of hydration reaction and in the mechanism of crystallization, but they all result in 3Ca
O · 2SiO match with ₃ · 3H ₂ O points forming a calcium silicate hydrate of the form. On the other hand, as another main compound, 3Ca was added to the phase containing alumina (Al ₂ O ₃ ).
O.Al ₂ O ₃ (tricalcium aluminate) and 4CaO.
Al ₂ O ₃ .Fe ₂ O ₃ (tetracalcium aluminate), which reacts with water to form 3CaO.Al ₂ O ₃ .6H
Crystals of the form ₂ O precipitate. In this connection, when sulfate groups (SO ₃ ) are present, lime aluminate hydrate becomes SO ₃
And form an inorganic double salt. This is ettringite (3CaOA
l ₂ O ₃ .3CaSO ₄ .3H ₂ O). This ettringite is a crystal that encapsulates heavy metals in cement. Although owns 32 molecules also water in a molecule as a unit of the crystal structure, the supply of SO ₃ is eliminated when 3CaO
-Conversion to Al ₂ O ₃ .CaSO ₄ .12H ₂ O causes such a conversion to change the density of the structure and to reduce the bonding force due to generation of free water. The product of the present invention (hereinafter sometimes referred to as “new hard”) has latent hydraulic properties and exhibits hydraulic properties by stimulating action such as alkali or sulfate. The basicity value (CaO
+ Al ₂ O ₃ + MgO)% / SiO ₂ % is 1.35 to 1.
About 45. Compared with Portland cement, its basicity is about 1% lower and its hydration power is lower. For this reason, Portland cement and incineration ash are mixed and pulverized to enhance hydration and hardening properties. Portland cement is 10% cement
At about 30%, the properties of the new hard are different depending on the composition ratio and the fineness of the compounds contained in the incineration ash.
In addition, since New Hard does not react with water and carbon dioxide, it is not weathered and solidified like cement. Newhard contains a large amount of alumina and magnesium, which react strongly, compared to calcium.
The reaction rate is high and the expansion coefficient is high. Calcium hydroxide exerts a re-reaction due to the potential hydraulic property of New Hard around 28 days before the cement age, and hydration proceeds to help the hydration power of the cement. Newhard is strong against seawater, sewage and groundwater structures. The reason why the concrete structure is easily broken is that sulfate combines with Ca (OH) ₂ in the concrete to form calcium sulfate (CaSO ₄ ), and further, tricalcium aluminate hydrate (3CaO · Al ₂ O ₃₎ NH ₂ O) to form cement patilus. Newhard has a large expansion coefficient and the reaction starts early, so C
Since a (OH) ₂ is reduced and C ₃ A is also reduced, resistance is increased more. Because New Hard has a large surface activity, it has excellent foaming and dispersing ability required for solidification,
It is fluid and combines these aspects to promote the hydration of cement. Since the active energy of the foaming ability and the dispersing ability is high, the soil having a high viscosity is physically and chemically changed to sand in 24 hours. Further, there is a characteristic that the strength reinforcement such as ground improvement has water permeability and strength.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to embodiments. The present invention is not limited by these examples.

Example 1 As incineration ash samples, those collected from a stoker type incinerator and a fluidized bed type incinerator were used. With reference to FIG. 1, functions of a reduction reaction facility, a stabilization reaction facility, a flue gas treatment facility, and the like of the incineration ash recycling plant system will be described.

1) Receiving / supply equipment: Receiving: raw ash receiving pit 100 m ³ , supply: ash crane 13 ton / h, receiving hopper 10 m ³ , feeder 1
5 ton / h 2) Sorting equipment: Particle size sorting: Vibrating sieve (screen mesh 50)
mm, particle size 50 mm or less, particle size 50 mm or less, to the next step) iron separation: magnetic separator [excluding iron (relatively coarse iron)] 3) reduction reaction equipment: atmosphere temperature about 900 ° C, incineration ash temperature about 600 ° C, treatment Approximately 40 minutes, additives (reaction accelerator 2
~ 3% addition, hydrosodalite, metal catalyst, etc.), oxygen concentration about 6%, heating source (Heavy oil A) Main reaction (dechlorination of organic chlorine compounds; decomposition of dioxins in ash, thermal decomposition of organic chlorine compounds) Decomposition of dioxins in furnace, reduction of oxidized heavy metals; activation of heavy metals) 4) Crushing / crushing equipment: Crushing equipment: particle size of 10 to 20 mm or less, sorting of iron: excluding iron (relatively fine iron), grinding Treatment: Particle size 100 mesh (95%) 5) Stabilization reaction equipment: Treatment temperature about 180 to 200 ° C, treatment time about 60 minutes, additives (addition of 2 to 3% of reaction accelerator, catalyst, metal sulfide, etc.), oxygen Concentration about 6% Heating source (use of waste heat), main reaction (sulfurization of heavy metals; stabilized as sulfide) 6) Mixing and bagging equipment: tank: raw material tank 40m ³ , cement tank 40m ³ , quantitative feeder: Loss in weight, mixed : Rotary disk type continuous, bagging machines: capacity 8t
on / h, weighing 1000 kg / bag 7) Smoke exhaust treatment equipment: quenching cooling device (180 with heat exchanger)
℃), activated carbon adsorption (adsorption of dioxins, HCl, etc.), back filter (entrance temperature 180 ° C or less, prevention of regeneration of dioxins) 8) Electricity and instrumentation equipment: power receiving equipment, start-up panel, control panel, central Operation panel, on-site operation panel, measurement monitoring system, ITV monitoring device

When the concentration of dioxins in the fly ash raw ash was measured, the "toxic equivalent" was "0.000". In addition, an evaluation experiment for the elution of heavy metals from the product was conducted. A mixture of the generated incineration ash and cement at a weight ratio of 4: 1 was inspected for metals contained therein. A test solution (three types of pH 4, 7, and 9) in which the sample and the solvent were mixed at a weight ratio of 10% was continuously shaken at room temperature and normal pressure for 6 hours using a shaker. The test item "alkylmercury compound" was 0.1.
Less than 0005 mg / l, "mercury or its compound" is less than 0.0005 mg / l, "cadmium or its compound" is less than 0.01 mg / l, and "lead or its compound" is less than 0.1 mg / l , “Hexavalent chromium or its compound” was less than 0.01 mg / l, “arsenic or its compound” was less than 0.01 mg / l, and “selenium or its compound” was less than 0.01 mg / l. .

Example 2 As the incineration ash sample, one collected from a stoker type incineration plant was used. As in the first embodiment, the incineration ash recycling plant system includes a reduction reaction facility, a stabilization reaction facility, and a flue gas treatment facility (see FIG. 1). In this embodiment, as shown in FIGS. 3 and 4, a drying treatment facility is attached. In this embodiment, an electronic furnace is used in the secondary reaction processing step (second kiln). There is no emission of odors, smoke, harmful gases, or other substances that cause pollution. It is also possible to control the temperature constant or to control it remotely.
There is an advantage that safety and reliability are high and maintenance costs are low.
As a disadvantage, the cost increases when the heating capacity is large.
The heating element has a coil-shaped heating resistance wire in the center of the metal protection body, and is filled with special insulating powder with high electrical insulation and good thermal conductivity, and heat conduction between the metal protection tube and the heating resistance body Insulates electricity while enhancing its properties, and it is physically processed and solidified. This device is 180 ° to the whole surface
A constant temperature of (+ -10 °) must be maintained and uniform heating is required. The time during the carbonization is 30 minutes, and if the temperature exceeds 200 °, the reaction is decomposed and is not stabilized. The amount of oxygen is set to 3% to suppress the reaction by the oxygen medium. In a reducing atmosphere, there are many elements that react more easily with sulfur than with oxygen. Particularly harmful elements. Conversely, silicates are more likely to be oxygen-bonded than sulfur.

(1) Decomposition treatment of dioxins Dry treatment step Treatment Furnace temperature 800 to 900 ° C Effect Reduction of moisture content of incinerated ash (2% or less) Thermal decomposition of dioxins in exhaust gas Pulverization treatment step Treatment Particle size of dried incinerated ash Reduction effect to 100 mesh or less Effect Improvement and stabilization of reaction rate by increasing surface area of incinerated ash Primary reaction treatment process (reduction treatment process) Treatment Additive (main component: calcium oxide + catalyst) Oxygen concentration in furnace 6% Exhaust gas treatment Equipment: Exhaust gas quenching device + bag filter (slaked lime powder) Effect Dechlorination and thermal decomposition of dioxins in incineration ash Ca2 ⁺ suppresses generation of chlorine compounds in exhaust gas Thermal decomposition of dioxins in exhaust gas ( 2) Heavy metal elution prevention treatment Drying process As described in (1) above Pulverization process As above (1) Primary reaction treatment step (reduction treatment step) As described in (1) above, secondary reaction treatment step (stabilization treatment step) Treatment Mixing additives Additives: Main components (silicon dioxide, sodium carbonate, calcium carbonate, anhydrous borane, calcium silicate) + catalyst Furnace temperature 180 ~ 400 ° C Oxygen concentration in furnace: about 6% Smoke exhaust treatment equipment: Exhaust gas quenching device + bag filter (slaked ash powder) Effect Stable solidification by hydrating secondary treatment ash, preventing elution of heavy metals Occurs.

[0032]

The present invention can provide an economical treatment method for detoxifying and recycling general incinerated ash. It is possible to provide a method for producing safe cement-based materials from general incinerated ash that will not pollute the environment with heavy metals and dioxins in the future. It is possible to provide a safe cement-based material that does not pollute the environment with heavy metals and dioxins from municipal incineration ash in the future while detoxifying the generated exhaust gas. Environmentally polluted incinerated ash recycle (cement-based material) that is not detected by dioxin analysis in incinerated ash recycle and that can prevent elution of heavy metals by accelerated tests in a strongly acidic environment by hydration It can be manufactured with no manufacturing method.

[Brief description of the drawings]

FIG. 1 is a diagram showing a flow of an incineration ash recycling plant system for carrying out a method of the present invention.

FIG. 2 is an explanatory diagram of a drying treatment step using an inert gas.

FIG. 3 is an explanatory drawing of a primary reaction treatment facility to which a drying treatment facility and a flue gas treatment facility of the present invention are attached.

FIG. 4 is an explanatory drawing of a secondary reaction treatment facility to which a drying treatment facility and a flue gas treatment facility of the present invention are attached.

FIG. 5 is an explanatory view of another type of secondary incinerator (for exhaust gas) to which the present invention can be attached.

[Explanation of symbols]

 1 supply crane equipment 2 receiving hopper 3 transport device 4 vibrating sieve 5 1 Magnetic separator 6 Transfer device 7 Reduction reaction device 8 Transfer equipment 9 Crusher 10 No. 2 magnetic separator 11 transfer device 12 crusher 13 transfer device 14 stabilization reaction device 15 transfer device 16, 17 raw material, cement tank 18, 19 transfer device 20, 21 No. 1, No. 2 fixed-quantity feeding machine 22 mixing machine 23 transfer device 24 bagging machine

Claims (12)

[Claims] The raw ash is dried in a process for detoxifying and recycling the incinerated ash which is maintained at a constant temperature and for a predetermined time in a low oxygen space insulated from the outside air. Incineration characterized by a drying process to reduce the water content by thermal treatment and to thermally decompose dioxins in exhaust gas, and a crushing process to increase the surface area of the dried ash Ash treatment method. 2. A space in a low oxygen state insulated from outside air,
2. The method for treating incinerated ash according to claim 1, wherein the step of treating while maintaining a constant temperature and a constant time is accompanied by a flue gas treatment step. 3. A low oxygen space insulated from outside air,
The step of performing treatment while maintaining a constant temperature and a constant time comprises a reduction reaction treatment step and a stabilization reaction treatment step.
Or 2) a method for treating incinerated ash. 4. The method for treating incinerated ash according to claim 3, wherein a drying treatment step and a drying treatment step are provided before the reduction reaction treatment step is started. 5. The method according to claim 1, wherein nitrogen gas is introduced in the drying step.
The heating is performed to a furnace temperature of 800 to 900C.
Any of the incineration ash treatment methods. 6. In the above-mentioned pulverizing treatment step, 100 to 100
The method for treating incineration ash according to any one of claims 1 to 5, wherein the incineration ash is pulverized into fine particles of 150 mesh. 7. The method for treating incinerated ash according to claim 1, wherein in said reducing reaction treatment step, the incinerated ash temperature is maintained at about 400 ° C. to 600 ° C. for 20 to 40 minutes. 8. The method for treating incinerated ash according to claim 1, wherein in the stabilization reaction treatment step, the treatment temperature is maintained at 200 ° C. to 450 ° C. for a time of 40 minutes to 60 minutes. 9. An apparatus for carrying out the method according to claim 1, comprising a drying processing apparatus, a pulverizing processing apparatus, a reduction reaction processing apparatus, and a stabilization reaction processing apparatus. Incineration ash processing equipment. 10. The incineration ash treatment device according to claim 9, wherein a smoke exhaust treatment device is attached to each of the reduction reaction treatment device and the stabilization reaction treatment device. 11. The incineration ash treatment apparatus according to claim 9, wherein the drying treatment apparatus and the reduction reaction treatment apparatus use the same apparatus. 12. The incineration ash treatment apparatus according to claim 9, further comprising a nitrogen gas mixing and circulation means.