JP2001027407A - Waste melting furnace and method for volume-reducing waste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent fire spreading of a thermite agent by providing a furnace chamber inclined down at a hearth toward a forward direction, and a waste reservoir formed at a rear side of the chamber, penetrating a thermite agent charging tube at an upper portion of the chamber, and providing a waste charging pusher at a ear portion of the reservoir. SOLUTION: In the case of volume-reducing a waste, when the waste is charged from a waste inlet 6 in a waste reservoir 4, the waste is formed as a deposit D1 on a waste shelf 5. This deposit D is pushed into a furnace chamber 3 by a waste charging pusher 7, and a deposit D2 is formed on a hearth 2a' of the chamber 3. Then, after a thermite agent is charged on the deposit D from a thermite agent charging tube 13, the deposit D2 of the agent and the waste is heated by a heating burner 15, and a termite reaction takes place. The waste molten and volume-reduced by the reaction and becoming a molten slag flows down on an oblique surface of the hearth 2a' from the oblique surface of the deposit D2, and discharged out of a molten slag discharge port 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a waste melting furnace. More specifically, a thermite reaction is caused using aluminum slag and metal oxides such as iron oxide discharged during iron making and steel making and copper oxide discharged during copper refining, and a large amount of reaction heat generated at this time is generated. Waste melting that reduces the volume of ash generated in garbage incinerators, sludge from various treatment plants, non-combustible waste, asbestos, etc. by reducing the volume and generates solidified materials that can be reused It relates to a furnace and a method for reducing waste volume.

[0002]

2. Description of the Related Art In recent years, toxic substances such as heavy metals and dioxins contained in wastes such as ash remaining after incineration of garbage discharged from households and factories, dust and soot collected by removing dust from combustion gas, and so on Substances are released into the environment and pose a problem.

[0003] Further, in a sewage treatment plant, sewage sludge discharged as dewatered cake and the like and asbestos discharged as waste when an old building is demolished require a large cost, or a treatment means. Without a problem.

[0004] In the above-mentioned current situation, melting treatment with a waste melting furnace has been attracting attention as a treatment means capable of reducing the volume of these wastes and making them reusable solidified materials. Have been.

Various types of melting furnaces such as a surface melting furnace, an internal melting furnace, a coke head melting furnace, an electric arc melting furnace, and an electric resistance furnace have been researched and developed as waste melting furnaces. From the standpoint of processing, maintainability,
There are many problems in practical use in terms of economy and the like.

On the other hand, a waste melting furnace whose operation cost is extremely low and which can melt the waste at an extremely high temperature, uses a large amount of heat generated during the reaction of thermite reaction between aluminum and a metal oxide. BACKGROUND ART A waste melting furnace utilizing a thermite reaction (a thermite melting furnace) has been developed in which a waste is melted by utilizing the same.

A conventional waste melting furnace is disclosed in
JP-A-169819 (hereinafter referred to as "A") contains "a mixture prepared by adding a thermite (reaction) agent to incinerated ash and heating the mixture to a thermite reaction temperature to cause a thermite reaction inside the mixture. In the thermite reaction furnace for melting and slag, treatment of incineration ash using thermit reaction in which the thermit reaction furnace is provided with a burner for directly heating and melting the preparation even after the start of the thermite reaction of the preparation during the reaction Apparatus "is disclosed.

Further, Japanese Patent Application Laid-Open No. Hei 10-277520,
Japanese Patent Application Laid-Open No. 10-277519 discloses that an ash and a thermite agent are supplied and kneaded at a fixed ratio into an extrusion kneader equipped with a screw feeder, and the kneaded material is crucible from the outlet of the tapered extruder. Waste melting furnace (hereinafter referred to as a thermite-mixed melt storage type waste melting furnace) which extrudes and throws into a reaction vessel in which a molten material such as is stored and melts the kneaded material stored in the reaction vessel by a thermite reaction. ) Are disclosed.

Further, Japanese Patent Application Laid-Open Nos. Hei 10-47640, Hei 10-43717, Hei 9-101014
In the publication, ash and a thermite agent are supplied and kneaded at a fixed ratio to an extrusion kneader provided with a screw feeder, and the kneaded material is horizontally expanded from a discharge port of the tapered extrusion kneader. A waste melting furnace (hereinafter referred to as a thermistor kneading / melting logistics) that extrudes into a flow-type reaction vessel such as a crucible and melts the kneaded material by a thermite reaction in the reaction vessel and discharges the melt down. This is referred to as a melting furnace.

[0010]

However, the above-mentioned conventional waste melting furnace has the following problems. (1) When the mixture of the thermite agent and waste (hereinafter referred to as the thermite agent mixture) spreads at the input port side due to thermite reaction heat, the operation of the melting furnace is performed in the case of an earthquake or fire. In case of an emergency stop,
The operation cannot be stopped until the thermite agent mixture charged into the melting furnace has reacted. Since the thermite agent mixture is bulky because the thermite agent and the waste are mixed, a long time is required from when the introduction of the thermite agent mixture is stopped to when the reaction is completed, and a long time is required until the emergency stop. (2) The melting temperature is controlled by the mixing ratio between the thermite and the waste because the components of the waste vary widely and the amount of water contained in the waste and the ratio of other evaporable components also vary. Is practically impossible, and it is difficult to perform an effective melting treatment with a minimum thermite agent. (3) The waste to be charged varies in particle diameter, specific gravity, angle of repose, spatula angle, and the like, and it is difficult to uniformly mix the thermite and the waste. When the distribution of the thermite agent in the thermite agent mixture is not uniform, it is difficult to keep the melting temperature constant, and it is also difficult to maintain the thermite reaction in a chain.

Further, the waste melting furnace disclosed in Japanese Patent Publication No. A has the following problems. (4) In order to continuously maintain the melting of the waste, heating by a burner is always required, so that the cost required for melting the waste is high, and a large amount of energy is required for the melting.

[0012] The waste melting furnaces of the thermite agent kneading melt storage type and the thermit agent kneading melt flow type have the following problems. (5) Since the thermite reaction is caused to occur while the thermite agent mixture is charged into the furnace, the inter-particle distance of the thermite agent in the thermite agent mixture necessarily increases.
The thermite agent is a mixture of a metal oxide powder and an aluminum powder at a fixed ratio.The thermite reaction is an oxidation-reduction reaction that occurs when the metal oxide powder and the aluminum powder are in contact with each other. When the distance between the particles increases, the rate of contact between the metal oxide powder and the aluminum powder decreases, and the reaction efficiency rapidly decreases. When the reaction efficiency is low, it is difficult to maintain the thermite reaction in a chain, and it is necessary to constantly heat from the outside, resulting in poor energy efficiency. (6) In order to improve the reaction efficiency of the thermite reaction, when the compounding ratio of the thermite agent in the thermite agent mixture is increased,
A large amount of thermite agent required for melting the waste is required, which wastes resources and increases running costs. The thermite reaction is an exothermic reaction that generates an extremely large amount of heat, and the temperature inside the furnace becomes extremely high due to the heat of the reaction. Therefore, in order to suppress the reaction amount up to the heat resistance limit of the furnace wall, it is necessary to suppress the input amount of the thermite mixture,
Limits on waste disposal efficiency. In addition, there is a possibility that the spark which has been ignited may cause the thermite reaction to spread to the input port side of the thermite agent mixture, and there is a problem in safety. As a countermeasure, it is said that the spread of fire is prevented by detecting the spread of fire with a detection sensor and injecting nitrogen.However, the thermite reaction is a reaction that occurs without oxygen and generates a large amount of heat. It is practically difficult to prevent the spread of the fire only by the cooling effect of the gas. (7) In the thermite reaction, sparks are scattered and the reaction occurs violently. Therefore, the impact during the thermite reaction causes the aluminum pieces to be repelled, and the aluminum does not sufficiently react. (8) The furnace body is complicated and lacks productivity, and lacks maintainability. (9) Lack of effective utilization of the thermite reaction, and lack of resource saving and energy saving.

The present invention solves the above-mentioned conventional problems, and can prevent the spread of a thermite agent, is excellent in safety, can control the melting temperature by a thermite reaction, and lowers the furnace temperature. It is possible to stably maintain the thermite reaction in a chain,
High thermal efficiency of waste melting processing, low running cost required for melting processing, and excellent waste processing capacity,
An object of the present invention is to provide a waste melting furnace having excellent durability.

Further, the present invention solves the above-mentioned conventional problems, in which the melting temperature can be controlled by a thermite reaction, the thermite reaction can be stably maintained in a chain, and the heating air can be used. An object of the present invention is to provide a waste volume reducing method which burns while drying, has high thermal efficiency of waste melting treatment, has excellent waste treatment performance, and has low running cost for melting treatment.

[0015]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a waste melting furnace according to the present invention has a furnace body, and a furnace floor formed inside the furnace body and having a hearth inclined downward toward the front. A furnace chamber formed, a waste reservoir formed at the rear of the furnace chamber, a waste inlet opening to the waste reservoir, a molten slag outlet opening to the front of the hearth, A configuration comprising: a thermite agent supply pipe penetrating the upper part of the chamber; and a waste input pusher disposed behind the waste storage part and for pushing waste stored in the waste storage part to the furnace chamber. Consisting of

With this structure, it is possible to prevent the spread of the thermite agent and to provide excellent safety, to control the melting temperature by the thermite reaction, to lower the furnace temperature, and to reduce the thermite reaction. It is possible to maintain a stable and continuous chain, high thermal efficiency of waste melting treatment, low running cost required for melting treatment, and excellent waste treatment capacity and excellent durability. A furnace can be provided.

Further, in order to solve the above-mentioned problems, a waste volume reducing method of the present invention is characterized in that waste is deposited in an inclined manner on an inclined surface, and a thermite is dropped and supplied on the inclined surface of the waste.
The thermite agent is heated to cause a thermite reaction, the waste deposited on the lower portion of the thermite agent by the thermite reaction is melted, and the molten waste flows down to the lower portion of the inclined surface and is discharged.

With this configuration, the melting temperature can be controlled by the thermite reaction, the thermite reaction can be stably maintained in a chain, and the waste is burned while being dried with heated air. High thermal efficiency,
In addition, it is possible to provide a waste volume reducing method which has excellent waste treatment capacity and low running cost required for melting treatment.

[0019]

In order to achieve the above object, a waste melting furnace according to claim 1 of the present invention comprises a furnace body, and a furnace floor formed inside the furnace body and having a hearth portion facing forward. A furnace chamber inclined downward, a waste storage section formed at the rear of the furnace chamber, a waste inlet opening to the waste storage section, and a molten slag opening to the front of the hearth section. A discharge port, a thermite injection pipe penetrating the upper part of the furnace chamber, and a waste input pusher disposed at the rear of the waste storage section and for pushing waste stored in the waste storage section to the furnace chamber. , Is provided.

With this configuration, the following operation can be obtained. (1) The waste to be melted and reduced in volume is thrown into the waste storage from the waste inlet. The waste put into the waste storage unit is pushed into the furnace chamber by the waste input pusher, and the waste accumulated in the furnace room from the waste storage unit at the rear is inclined forward (toward the molten slag discharge port). create.
A thermite is dropped from the thermite injection pipe onto the inclined surface of the waste accumulation, and the dropped thermite is heated and ignited by a heating means such as a burner to start a thermite reaction. The waste is melted by a large amount of high-temperature heat generated by the thermite reaction of the thermite agent, flows down the hearth, and is discharged from the molten slag discharge port. Once the thermite reaction occurs, if the thermite agent is successively supplied, the thermite reaction continues in a chain by a large amount of heat generated by the thermite reaction, and the continuous melting of the waste is performed. When the waste melts out from the bottom of the waste accumulation, the bottom of the waste accumulation is removed, and the waste and thermite fall from the back of the waste accumulation to the front, and fall into the melting area. Is supplied with waste and thermite sequentially. In addition, the waste input pusher sequentially pushes and supplies the waste from the waste storage unit. (2) Since the thermite agent is sequentially dropped and supplied on the inclined surface of the waste accumulation, the supply rate of the thermite agent can be adjusted while monitoring the state of the melting of the waste by a monitoring camera or the like, so that the melting is performed. The temperature can be easily adjusted. (3) In an emergency, by stopping the supply of the thermite agent, it is possible to immediately stop the melting of the melting furnace. Further, since the waste storage chamber is formed at the rear part of the furnace body and one step higher, it is possible to prevent the burning of the hearth by the heat of the furnace floor part and to facilitate the combustion control. (4) Since the thermite agent is not mixed very much with the waste material and is deposited on the waste material, the compounding ratio of the thermite agent can always be maintained at the optimum compounding ratio for the thermite reaction. The reaction can be performed efficiently. Since the amount of heat generated by the thermite reaction is extremely large and the temperature is high, the ash at the lower part of the thermite agent is 2,500-2650 by the heat generated by the thermite reaction.
Heated to ° C and melted. At this time, the thermite agent is also melted, and melts and erodes the lower waste while causing a thermite reaction. Therefore, the melting of the waste is also efficiently performed. In addition, even when the amount of water and other volatile components contained in the waste is large, an effective melting treatment can be performed with a minimum thermite agent. In other words, in the thermit melting furnace, improving the contact ratio between the aluminum and the metal oxide of the thermite agent is an important point in performing the reaction with high efficiency, and thereby performing efficient melting treatment. Thermit agent is dropped on the waste, and the thermit agent mixed in the optimal ratio is reacted on the waste, and the heat of the reaction or the heat of the melt melted by the heat of the reaction causes the waste in the lower part of the waste. , It is possible to perform an efficient melting process. (5) Since the thermite agent is dropped and supplied from the upper part of the furnace chamber, it is possible to prevent the thermite reaction from being chained to the upper thermite agent. If the thermite agent spreads, if the supply of the thermite agent is stopped, the spread of the thermite reaction can be prevented and the safety is high. (6) Since the waste input pusher is used to input the waste from the waste storage unit to the furnace chamber, it is possible to increase the speed of inputting the waste into the furnace chamber, and to perform a large amount of waste in a short time. The material can be melted. Further, even fibrous waste and low-fluid waste such as asbestos are pushed by the waste input pusher, so that the waste can be smoothly input into the furnace chamber.

Here, the waste storage section is configured to have a horizontal floor with a step relative to the furnace chamber, or a floor with a step inclined downward in the furnace chamber direction relative to the furnace chamber. You.

The thermite injection pipe is disposed vertically or inclined, but is preferably disposed vertically. This is because the supply of the thermite agent becomes smooth, and it is easy to increase the supply speed of the thermite agent. In addition, by arranging the thermite agent supply pipe vertically, the thermit agent is prevented from adhering to the thermite agent supply pipe,
It is also possible to prevent the thermite reaction from being linked to the thermite injection tube.

It is preferable that the thermite agent is charged into the thermite agent supply tube using a rotary feeder. This is because even if sparks due to the thermite reaction scatter in the thermite injection tube, the rotary feeder can prevent the spread of the thermit reaction to the upper portion.

As the thermite agent, a product obtained by pulverizing aluminum and a metal oxide into a granular form is used. A mixture of aluminum and iron oxide or copper oxide or slaked lime or the like so as to form a thermite compound is used. A material compacted with a compacting agent is preferably used.

As the aluminum, not only high-purity aluminum but also aluminum slag which is generated in a large amount in the step of re-melting aluminum in an aluminum manufacturing plant, aluminum cans for canned beverages and the like can be used.

As iron oxide and copper oxide, not only high-purity iron oxide (Fe ₂ O ₃ , Fe ₃ O _4, etc.) and copper oxide, but also a steel mill or a steel mill continuously casts molten steel and draws it out. It is also possible to use an iron scale, a copper piece or a copper scale of a copper mill, which is generated in a large amount when cooling or rolling or forging a steel ingot or a steel slab.

The average particle size of the thermite agent is 0.00
04 mm to 5 mm or less, preferably 0.004 mm to 2
mm. As the average particle size exceeds 2 mm, only the aluminum particles are repelled during the reaction, so that the reactivity of the thermite reaction tends to deteriorate, and the particle size becomes 0.004.
When the diameter is smaller than mm, the ignitability and reactivity tend to be deteriorated due to moisture absorption, which is not preferable.

The waste is not limited to incineration ash remaining after incineration of garbage, but is not limited to residue, crushed green tape which is waste containing hexavalent chromium, asbestos,
It may be a waste such as a dried sewage sludge. As for the waste, a powdery material such as ash is initially charged as it is, but a lumpy waste has an average particle diameter of 0.001 mm to 50 mm, preferably 0.01 m before being charged.
It is preferable to grind to a size of m to 8 mm. This is because melting becomes difficult as the particle size exceeds 8 mm, and handling becomes difficult if the particle size is 0.01 mm or less.

According to a second aspect of the present invention, there is provided the waste melting furnace according to the first aspect, further comprising a partition plate extending from the upper part of the furnace chamber into the furnace chamber in front of the thermite agent charging pipe. And a heating burner disposed above the furnace chamber in front of the partition plate.

According to this configuration, the following operation can be obtained in addition to the operation of the first aspect. (1) After dropping a thermite agent on the slope of the pile of waste put in the furnace chamber, the heating burner is ignited, and the thermite agent and the thermite agent on the pile of the waste are heated by the flame injected from the heating burner. I do. The heat of the flame ignites the thermite agent, causing a thermite reaction. Once the thermite reaction occurs, if the thermite agent is supplied sequentially, a large amount of high-temperature heat generated by the thermite reaction causes the thermite reaction to continue in a chain. When the melting of the waste proceeds, the melting zone expands and heat is stored to some extent in the waste and furnace around the melting zone, and the thermite reaction becomes stable and continues in a chain. To stop. Once the thermite reaction becomes stable and sustained in a chain, the heating burner is used as a backup when the thermit reaction is interrupted, and when the thermite reaction is interrupted, the heating burner is ignited, The thermite agent is ignited by heating with a flame to maintain a state in which the waste is continuously melted. (2) The airflow generated by the flame from the heating burner is shielded by the partition plate, so that the airflow to the rear part of the partition plate in the furnace chamber is prevented. Thereby, the thermite agent is scattered in the furnace chamber and the floating of the thermite agent in the furnace chamber is suppressed, and the thermite agent supplied to the furnace chamber can efficiently contribute to the thermite reaction. (3) The thermite reaction is originally a chain reaction caused by heat generated by the reaction, but the supply of the thermite agent is not continuously maintained in the melting region where the thermite reaction occurs due to collapse of waste. In some cases, the reaction may be terminated and may not last. In such a case, the melting region is always heated by the flame of the heating burner, and the thermite agent is re-ignited, whereby the thermite reaction can be continuously generated. (4) Since the heating burner is provided, the waste accumulated in the furnace chamber can be dried. (5) The partition plate can prevent the flame of the heating burner from directly hitting the thermite injection tube and prevent the thermite injection tube from being heated, thereby preventing a sudden thermite reaction in the thermite injection tube. Can increase safety.

Here, as the heating burner, an oil burner, a gas burner or the like is used.

The third aspect of the present invention is the first or second aspect.
The furnace according to claim 1, wherein the furnace body cooling jacket disposed on an outer wall from the bottom to the side of the furnace body, a cooling air inlet pipe communicating with the furnace body cooling jacket, and a furnace body cooling jacket. And a cooling air discharge pipe communicating with the cooling air discharge pipe.

According to this configuration, the following operation can be obtained in addition to the operation of the first or second aspect. (1) Since the hearth is externally cooled by cooling air in the furnace body cooling jacket, the underflow portion of the molten slag solidifies on the hearth to form a solidified layer. It flows above and is discharged outside the furnace chamber from the molten slag discharge port. Since there is a very large temperature gradient between the hearth and the molten slag, this solidified layer does not adhere to the hearth and can be easily peeled and removed later. (2) Since the molten slag does not flow directly on the hearth due to the solidified layer formed on the hearth, the hearth is protected by the solidified layer and deterioration due to the molten slag flow is prevented.

The invention according to claim 4 is the invention according to claim 2 or 3
The waste melting furnace according to the above, a configuration provided with a fumarole disposed in the upper part of the furnace chamber in front of the partition plate, a combustion air supply pipe communicating with the cooling air discharge pipe and the fumarole, It was done.

According to this configuration, the following operation can be obtained in addition to the operation of the second or third aspect. (1) The cooling air in the furnace body cooling jacket is heated by exchanging heat with the furnace bottom wall. The heated air is injected from a fuze section through a combustion air supply pipe as combustion air toward a melting region on a stack of waste in the furnace chamber. In the flame from the heating burner injected into the melting area,
Since the heated combustion air injected from the blowing section is supplied, the thermal efficiency is remarkably improved, the waste is efficiently melted, and the energy saving property is excellent. (2) The air supplied from the fumarole promotes the combustion reaction by supplying oxygen to the flame from the heating burner, thereby increasing the temperature of the flame from the heating burner. Heating is performed.

In the waste volume reducing method according to the fifth aspect of the present invention, waste is deposited in an inclined manner on an inclined surface, a thermite agent is dropped and supplied on the inclined surface of the waste, and the thermite agent is supplied. Heat to cause a thermite reaction, melt the waste deposited at the bottom of the thermite agent by the thermite reaction,
This is a configuration in which the molten waste flows down to the lower part of the inclined surface and is discharged.

With this configuration, the following operation is obtained. (1) Since the thermite agent is sequentially dropped and supplied onto the inclined surface of the waste accumulation, the supply rate of the thermite agent can be adjusted while monitoring the state of the melting of the waste, and the adjustment of the melting temperature is easy. Can be done. (2) In an emergency, by stopping the supply of the thermite agent, it is possible to immediately stop the melting of the melting furnace. (3) Since the thermite agent is not mixed very much with the waste material and is deposited on the waste material, it is possible to always maintain the compounding ratio of the thermite agent at the optimum compounding ratio for the thermite reaction. The reaction can be performed efficiently. The amount of heat generated by the thermite reaction is extremely large, and the ash below the thermite agent is heated to 2500 to 2650 ° C. and melted by the heat generated by the thermite reaction. At this time, the thermite agent is also melted, and melts and erodes the lower waste while causing a thermite reaction.
Therefore, the melting of the waste is also efficiently performed. Further, even when the amount of water and other volatile components contained in the waste is large, an effective melting treatment can be performed with a minimum thermite agent. (4) Since the thermite agent is dropped and supplied from the upper part of the furnace chamber, it is possible to prevent the thermite reaction from spreading to the upper thermite agent. If the thermite reaction spreads, if the supply of the thermite agent is stopped, the spread of the thermite reaction can be prevented, and the safety is high.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a sectional side view of a main part of a waste melting furnace according to Embodiment 1 of the present invention, and FIG.
FIG. 4 is a cross-sectional view taken along line -A.

1 and 2, reference numeral 1 denotes a waste melting furnace, 2 denotes a furnace body of the waste melting furnace 1 made of a refractory castable such as SiC or an adiabatic castable, and 2a denotes a bottom of the furnace body 2. A furnace bottom wall 2 a ′ is formed by being inclined downward at a predetermined angle toward the front of the furnace body 2,
2b is a furnace ceiling constituting the upper part of the furnace body 2 and 2c is a furnace body 2
The front furnace wall 2d constitutes the left and right side walls of the furnace body 2, 2d is the furnace side wall constituting the left and right side walls of the furnace body 2, 3 is formed inside the furnace body 2 and the hearth 2a 'is directed forward by a predetermined angle. A furnace chamber 4 inclined downward is formed at a rear part of the furnace body 2, a waste storage part for temporarily storing waste to be put into the furnace body 2, and 5 is a waste storage part 4. A waste loading shelf 6 which constitutes a floor and is formed in a horizontal plane that is higher than the furnace floor 2 a ′ of the furnace chamber 3 by a predetermined height in a stepped manner, 6 is directed forward toward the rear upper surface of the furnace body 2. A waste input port 7 formed to be inclined and provided for inputting waste into the waste storage section 4 is disposed at the rear of the waste storage section 4 and deposited on the waste input shelf 5. Waste pusher for pushing waste waste into the furnace chamber 3, a pusher support stand 8 for supporting a lower portion of the waste input pusher 7 on the furnace body 2, and a front part 9 of the furnace body 2. Rosokokabe 2a in a molten slag discharge port for discharging the molten slag into furnace chamber 3 out of vertically penetrated by furnace chamber 3.

The hearth 2a 'is preferably formed to be inclined forward at an angle of 3 to 10 degrees, more preferably 5 to 8 degrees. This is an angle that has been found empirically to make it easier for the molten product (molten slag) of the reaction product of the thermite agent and the waste to flow smoothly when the waste is melted by thermite reaction. It is. Needless to say, this angle needs to be large in the case where the waste having a high viscosity of the molten slag, such as asbestos, is exclusively melted. As the inclination angle of the hearth 2a 'becomes smaller than 5 degrees, when the flow rate of the molten slag is small, the residence time becomes longer and the molten material is intermittently discharged as a lump, which hinders the post-treatment process. When the inclination angle exceeds 8 degrees, unmelted substances tend to accompany unmelted molten slag with high viscosity, which is not preferable. In particular, when the inclination angle is less than 3 degrees or 10 degrees or more, this tendency becomes remarkable, and neither is preferable.

The inclination angle of the waste inlet 6 varies depending on the type, dryness, and properties of the waste to be introduced.
In general, it is preferable to form them at an angle of 55 to 85 degrees. This angle is also a value found by experiment.

Reference numeral 10 denotes a working opening which is provided through the front furnace wall 2c and is provided for performing maintenance work, etc., 11 denotes a working cover which is disposed in the working opening 10 so as to be able to freely discard money, and 12 denotes a furnace cover. Furnace bottom wall 2a
This is a furnace body cooling jacket that is disposed along the outer wall from the furnace bottom wall 2d (see FIG. 2) to the left and right furnace side walls 2d from the furnace bottom wall 2a.

The cooling efficiency is improved by forming a zigzag ventilation passage with a buffer plate or the like so that cooling air circulates uniformly inside the furnace cooling jacket 12 inside the furnace body cooling jacket 12. Such a structure is preferable.

Reference numeral 13 denotes a thermite injection pipe made of a tubular body vertically penetrating the furnace ceiling 2b and having a lower end extending into the furnace chamber 3 and opening. Reference numeral 14 denotes a front of the thermite injection pipe 13 in the furnace ceiling 2b. A burner injection port 15 having a conical opening extending toward the furnace chamber 3 and extending inward toward the furnace chamber 15 has a flame injection port arranged toward the burner injection port 14 to supply a flame into the furnace chamber 3. A heating burner that injects and heats the inside of the furnace chamber 3, 16 is a combustion air supply pipe that is disposed above a front part in the furnace chamber 3 and introduces combustion air into the furnace chamber 3, and 16 a is a front side in the furnace chamber 3. A hollow cylinder having a large number of holes and communicating with the combustion air supply pipe 16 and having a plurality of holes, the combustion air 16b having a plurality of holes opened to the combustion cylinder 16a and fed into the combustion cylinder 16a. A blowing port for injecting the gas into the furnace chamber 3, and a furnace 17 is provided in front of the thermite injection pipe 13 in the furnace chamber 3. The tip is formed to extend downward from the well portion 2b, and the tip portion extends slightly below the thermite injection tube 13 to prevent scattering of waste and to prevent the heating of the thermite injection tube 13. A flat partition plate, D ₁ is a stack of waste put into the waste storage unit 4,
D ₂ is the accumulation of the waste put into the furnace chamber 3, R ₁ is the melting region of the waste, L ₁ is the heating burner 15 and the burner injection port 14
Center axis of the, L ₂ is the center axis of the jet ports 16b.

The partition plate 17 prevents the flame injected by the heating burner 15 and the combustion air injected from the blast tube 16a from flowing to the rear part of the furnace chamber 3, and prevents the thermite agent from scattering into the furnace chamber 3. I do.

The center axis L ₁ of the heating burner 15 and the burner injection port 14 is aligned with the hearth 2 in front of immediately below the partition plate 17.
It is formed toward a '. This is because the waste input shelf 5 is formed stepwise higher than the hearth portion 2a 'of the furnace chamber 3 by a predetermined height, and the waste is supplied from the waste storage section 4 at the rear of the furnace chamber 3. Therefore, the accumulation D ₂ of the waste put into the furnace chamber 3 that accumulates on the hearth 2 a ′ is forward (the molten slag discharge port 9).
Inclined downward toward the side) was deposited on the hearth unit 2a ', thermite agent was dropped on the top surface of the deposition D ₂ of the waste collapsed on slope deposition D ₂ waste forward Therefore, a large amount of thermite reaction mainly occurs in the front (on the side of the molten slag discharge port 9) than immediately below the partition plate 17.
Therefore, in order to direct the flame of the heating burner 15 to a point where the thermite reaction occurs most, the central axis L ₁ is directed to the hearth 2 a ′ in front of (below the molten slag discharge port 9) immediately below the partition plate 17. ing.

Similarly, since the combustion air is supplied into the furnace chamber 3 to promote the heating of the thermite and the waste by the heating burner 15, the center axis L ₂ of the blast port 16b is It is formed toward the hearth 2a 'in front of the partition plate 17 (on the side of the molten slag discharge port 9).

Numeral 12a denotes a cooling air inlet pipe formed on the side of the furnace body cooling jacket 12 for feeding air into the furnace body cooling jacket 12, and reference numeral 12b denotes a side opposite to the air inlet 12a of the furnace body cooling jacket 12. A cooling air discharge pipe formed on the side to discharge air from the furnace body cooling jacket 12, a buffer plate 12c disposed inside the furnace body cooling jacket 12 to increase cooling efficiency, and a cooling air discharge pipe 18 A combustion air supply pipe which communicates with the combustion air supply pipe 12b and cools the furnace body 2 in the furnace body cooling jacket 12 and supplies heated air to the combustion air supply pipe 16 as combustion air. A cooling air exhaust valve composed of an on-off valve connected to the discharge pipe 12b and the other end connected to an external exhaust pipe (not shown), and a circulating air valve 18b composed of an on-off valve disposed on the combustion air supply pipe 18 , Reference numeral 8c denotes a combustion air pressure detector which is disposed on the combustion air supply pipe 18 and detects the air pressure inside the combustion air supply pipe 18, and 19 denotes a monitor camera which is provided at the front of the furnace ceiling 2b. The monitoring camera attachment port 20 is a monitoring camera disposed outside the furnace body 2 toward the monitoring camera attachment port 19.

The waste melting furnace configured as described above will be described below with reference to a method for reducing the volume of the waste.

First, the waste to be melted is introduced into the waste storage unit 4 from the waste inlet 6. At this time, the waste is preferably dried in advance by a drying device in order to reduce the angle of repose and spatula angle, increase the fluidity index of Carr, and prevent the waste inlet 6 from being blocked. Further, in the case of powder waste, it is better to improve the uniformity of the particle size of the waste particles by a sieve or the like in order to further increase the fluidity index of Carr.

The waste put into the waste storage 4 is
A stack D _{1 of} waste as shown in FIG. ₁ is formed on the waste input shelf 5 of the waste storage unit 4, and a part of the waste D ₁ falls into the furnace chamber 3. The waste deposit D ₁ is pushed into the furnace chamber 3 by the waste input pusher 7 to form a waste deposit D ₂ on the hearth 2 a ′ of the furnace chamber 3. Since waste is turned shelf 5 which are formed higher by a predetermined height stepwise to the hearth 2a of the furnace chamber 3 ', deposited D ₂ of the waste, the front (molten slag discharge port 9 side) It inclines downward and accumulates on the hearth 2a '.

In this state, the thermite injection tube 1
Than 3, to drop thermite agent from above onto the deposition of waste D _2. Thermite agent which is introduced onto the deposition D ₂ of the waste, to collapse the upper slope of the deposit D ₂ waste forward.

Next, the heating burner 15 is ignited, and the deposition D ₂ of the thermite and the waste is heated by the flame injected from the heating burner 15.

The heat of the flame ignites the thermite agent, causing a thermite reaction. Once the thermite reaction occurs, if the thermite agent is sequentially supplied, the thermite reaction continues in a chain due to the high heat generated by the thermite reaction.

At this time, simultaneously, the cooling air exhaust valve 18a
Is closed, the cooling air is supplied from the cooling air inlet 12a with the circulation air valve 18b opened, the air is circulated through the furnace body cooling jacket 12, and the air discharged from the cooling air discharge pipe 12b is discharged. Is supplied into the furnace chamber from a blast port 18b through a combustion air supply pipe 18, an air purge pipe 16 and a blast cylinder 16a. This combustion air promotes the combustion reaction by supplying oxygen to the flame from the heating burner 15, whereby the temperature of the flame from the heating burner 15 increases and heating is performed more efficiently. Will be

The waste is heated to a high temperature of 2500 to 2650 ° C. by the heat generated by the thermite reaction and melted. Thermite reaction occurs in molten region R ₁ shown mainly in FIG. 1, deposited D ₂ of the waste is melted from the front of the skirt portion, waste became molten slag is melted, volume reduction is waste It flows down the slope of the hearth 2 a ′ from the slope of the stack D _{2 and} is discharged from the molten slag discharge port 9 to the outside of the furnace chamber 3.

Since the hearth portion 2a 'is inclined toward the molten slag discharge port 9, the molten slag is discharged from the molten slag discharge port 9 to the outside of the furnace chamber 3 without staying in the hearth.

When the waste melts and flows out from the bottom of the waste stack D ₂ , the bottom of the waste stack D ₂ is removed, and the waste and the waste are arranged from the rear to the front of the waste stack D _2. thermite agent collapsed, the melting region R ₁ waste and thermite agent is supplied sequentially. Also, the waste input pusher 7
Thus, the waste is sequentially pushed and supplied from the waste storage unit 4.

Since the thermite agent is sequentially dropped and supplied onto the waste accumulation D ₂ , the supply rate of the thermite agent can be adjusted while monitoring the state of melting of the waste with the monitoring camera 20. The temperature can be easily adjusted.

In an emergency, by stopping the supply of the thermite agent, it is possible to immediately stop the melting of the melting furnace.

Since the thermite agent is not much mixed with the waste material and is deposited on the waste material, it is possible to always maintain the compounding ratio of the thermite agent at the optimum compounding ratio for the thermite reaction. The reaction can be performed efficiently. The amount of heat generated by the thermite reaction is extremely large, and the ash below the thermite agent is heated to 2500 to 2650 ° C. and melted by the heat generated by the thermite reaction. At this time, the thermite itself is also melted, and melts and erodes the lower waste while generating a thermite reaction. Therefore, the melting of the waste is also efficiently performed.

Since the hearth 2a 'is cooled from the outside by cooling air in the furnace cooling jacket 12, a part of the molten slag solidifies on the hearth 2a' to form a solidified layer.
The molten slag flows on the solidified layer and the molten slag outlet 9
It is discharged outside the furnace chamber 3. Since there is an extremely large temperature gradient between the hearth 2a 'and the molten slag, this solidified layer does not fuse to the hearth 2a' and is easily peeled later during maintenance work or the like. And can be removed.

Since the solidified layer prevents the molten slag from flowing directly on the hearth 2a ', the hearth 2a'
Is protected by the solidification layer and the furnace bottom wall 2 by the molten slag flow.
a is prevented from deteriorating.

The cooling air in the furnace body cooling jacket 12 is heated to 250 to 300 ° C. by exchanging heat with the furnace bottom wall 2a. The heated air is injected toward the melting region R ₁ on deposition D ₂ of the waste furnace chamber 3 as air for combustion from the jet ports 16b. The flame from the heating burner 15 to be injected into the melting region R _1, since the heated air for combustion ejected from the jet ports 16b are supplied, improves thermal efficiency, efficiently rows melt the waste Will be

The state of the melting of the waste in the melting region R ₁ is monitored by the monitoring camera 20.

[0066] thermite reaction is essentially the reaction is a chain occurring reaction due to the heat generated by, and the like collapse of waste, such as when the supply of the thermite agent melting region R ₁ is not last continuously Sometimes, the reaction ends and does not last. In such a case, the flame of the heating burner 15 to heat the continuously melting region R _1, causes continuously produce thermite reaction.

The flame from the heating burner 15 and the fumarole 16a
The airflow generated by the combustion air from the fumes 16b of
It is shielded by the partition plate 17 to prevent the airflow from flowing around the rear portion of the partition plate 17 in the furnace chamber 3. Thereby, the furnace chamber 3
The thermite agent is scattered in the inside, the floating of the thermite agent in the furnace chamber 3 is suppressed, and the thermite agent supplied to the furnace chamber 3 can efficiently contribute to the thermite reaction.

When the melting of the waste proceeds and the melting region R ₁ expands and heat is stored to some extent in the waste and furnace around the melting region R ₁ , the thermite reaction becomes stable and continues in a chain. , Stop the injection of the flame of the heating burner 15,
The cooling air exhaust valve 18a is opened, the circulation air valve 18b is closed, and the supply of combustion air is also stopped.

Once the thermite reaction has stably continued in a chain, the heating burner 15 is used as a backup when the thermite reaction is interrupted,
When the thermite reaction is interrupted, the heating burner 15 is ignited, and the thermite agent is ignited by heating with a flame to maintain a state in which the waste is continuously melted.

As described above, the heating burner 15 is used for igniting the thermite agent to assist the thermite reaction stably and sustainably.
It is also possible to set the temperature to 00 to 1000 ° C. and use it for applications such as drying the waste accumulated in the furnace chamber 3.

[0071]

As described above, according to the waste melting furnace of the present invention, the following advantageous effects can be obtained.

According to the first aspect of the present invention, (1) Since the thermite agent is sequentially dropped and supplied onto the inclined surface of the waste accumulation, the supply of the thermite agent is monitored while monitoring the state of the melting of the waste material. It is possible to provide a waste melting furnace in which the speed can be adjusted and the melting temperature can be easily adjusted. (2) In an emergency, by stopping the supply of the thermite agent, it is possible to immediately stop the melting of the melting furnace, thereby providing a highly safe waste melting furnace. (3) Since the thermite agent is not mixed very much with the waste material and is deposited on the waste material, it is possible to always maintain the compounding ratio of the thermite agent at the optimum compounding ratio for the thermite reaction. A waste melting furnace with high reaction efficiency can be provided. (4) The heat generated by the thermite reaction also melts the thermite agent and melts and erodes the lower waste while generating the thermite reaction, so that the waste can be efficiently melted. (5) Even if the amount of water and other volatile components contained in the waste is large, it is possible to perform an effective melting treatment with a minimum thermite agent. (6) Since the thermite agent is dropped and supplied from the upper part of the furnace chamber, the thermit reaction is prevented from spreading to the upper thermite agent, and if the thermit reaction spreads, the supply of the thermite agent is stopped. Then, the spread of the thermite reaction can be prevented, so that a highly safe waste melting furnace can be provided.

According to the invention described in claim 2, according to claim 1
In addition to the effects (1), it is possible to provide a waste melting furnace in which ignition of the thermite agent can be easily performed on the slope of the waste accumulated in the furnace chamber. (2) When the thermite reaction is interrupted, the heating burner is ignited, and the thermite agent can be ignited by heating with a flame, so that the melting of the waste can be performed stably and continuously. A furnace can be provided. (3) The air flow generated by the flame from the heating burner is shielded by the partition plate, and the air flow to the rear of the partition plate in the furnace chamber is prevented, so that the thermite agent scatters into the furnace chamber and thermit into the furnace chamber. The floating of the agent is suppressed, and the thermite agent supplied to the furnace chamber can efficiently contribute to the thermite reaction even during heating by the heating burner. (4) When the moisture content of the waste accumulated in the furnace chamber is high, a waste melting furnace capable of drying the waste accumulated in the furnace chamber by the heating burner can be provided.

According to the invention described in claim 3, according to claim 1
In addition to the effects of (2), (1) Since the hearth is cooled from the outside by cooling air in the furnace cooling jacket, a part of the molten slag solidifies on the hearth to form a solidified layer. The molten slag flows on the solidified layer and is discharged from the molten slag discharge port to the outside of the furnace chamber.The molten slag does not flow directly on the hearth, so the hearth is protected by the solidified layer and the molten slag is protected by the solidified layer. Deterioration due to slag flow is prevented. (2) Since there is an extremely large temperature gradient between the hearth and the molten slag, the solidified layer of the molten slag does not adhere to the hearth, and the solidified layer is easily separated and removed later. It is possible to provide a waste melting furnace which is easy to perform and excellent in maintainability.

According to the invention described in claim 4, according to claim 2,
In addition to the effects of (3), (1) the cooling air in the furnace body cooling jacket is heated by exchanging heat with the furnace bottom wall, and the heated air is
Since it is supplied to the flame from the heating burner injected into the melting zone, a waste melting furnace with high thermal efficiency can be provided. (2) The air supplied from the fumarolic portion promotes the combustion reaction by supplying oxygen to the flame from the heating burner, whereby the temperature of the flame from the heating burner rises and the waste having high heating efficiency A melting furnace can be provided.

According to the waste volume reducing method of the present invention, the following advantageous effects can be obtained.

According to the fifth aspect of the present invention, (1) Since the thermite agent is sequentially dropped and supplied onto the inclined surface of the waste accumulation, the supply of the thermite agent is monitored while monitoring the state of the melting of the waste material. It is possible to provide a waste volume reducing method capable of adjusting the speed and easily adjusting the melting temperature. (2) In an emergency, by stopping the supply of the thermite agent, it is possible to immediately stop the melting of the melting furnace, and it is possible to provide a highly safe waste volume reduction method. (3) Since the thermite agent is not mixed very much with the waste material and is deposited on the waste material, it is possible to always maintain the compounding ratio of the thermite agent at the optimum compounding ratio for the thermite reaction. A waste volume reducing method with high reaction efficiency can be provided. (4) Thermit agent is also melted by the heat generated by the thermit reaction, and the lower waste is melted and eroded while generating the thermit reaction, so that the waste volume can be efficiently reduced. Can be provided. (5) To provide a waste volume reducing method capable of performing an effective melting treatment with a minimum thermite agent even when the amount of water and other volatile components contained in the waste is large. be able to. (6) Since the thermite agent is dropped and supplied from the upper part of the furnace chamber, the thermit reaction is prevented from spreading to the upper thermite agent, and if the thermit reaction spreads, the supply of the thermite agent is stopped. If this is the case, the spread of the thermite reaction can be prevented, so that a highly safe waste volume reduction method can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional side view of a main part of a waste melting furnace according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

[Description of Signs] 1 Waste melting furnace 2 Furnace body 2a Furnace bottom wall 2a 'Furnace floor 2b Furnace ceiling 2c Front furnace wall 2d Furnace side wall 3 Furnace room 4 Waste storage unit 5 Waste input shelf 6 Waste Input port 7 Waste input pusher 8 Pusher support base 9 Melt slag discharge port 10 Work port 11 Work cover 12 Furnace body cooling jacket 12a Air inlet 12b Cooling air discharge pipe 12c Buffer plate 13 Thermite agent supply pipe 14 Burner injection port 15 Heating burner 16 combustion air feed pipe 16a squirting tube 16b jet ports 17 deposited R ₁ melting region L ₁ the center axis of the deposit D ₂ waste partition plates D ₁ waste L ₂ central axis

Claims (5)

[Claims] 1. A furnace body, a furnace chamber formed inside the furnace body and having a hearth portion inclined downward and forward, and a waste storage formed at a rear portion of the furnace chamber. Part, a waste inlet opening to the waste storage part, a molten slag outlet opening to the front of the hearth, a thermite agent inlet pipe penetrating the upper part of the furnace chamber, A waste input pusher disposed at a rear portion of the waste storage unit and for pushing waste stored in the waste storage unit into the furnace chamber; 2. A partition plate protruding from the upper part of the furnace chamber into the furnace chamber in front of the thermit agent charging pipe, and a heating burner disposed in the upper part of the furnace chamber in front of the partition plate. The waste melting furnace according to claim 1, comprising: 3. A furnace body cooling jacket disposed on an outer wall from the bottom to the side of the furnace body, a cooling air inlet pipe communicating with the furnace body cooling jacket, and communicating with the furnace body cooling jacket. The waste melting furnace according to claim 1, further comprising a cooling air discharge pipe. 4. A fuel supply system comprising: a fuze disposed at an upper part of the furnace chamber in front of the partition plate; and a combustion air supply pipe communicating with the cooling air discharge pipe and the fuze. The waste melting furnace according to claim 2 or 3, wherein: 5. A waste material is deposited in an inclined manner on an inclined surface, a thermite agent is dropped and supplied on the inclined surface of the waste material, and the thermite agent is heated to cause a thermite reaction. A method for melting waste, comprising: melting waste deposited on a lower part of a thermite agent; flowing the molten waste down a slope; and discharging the waste.