JP2008298306A - Portable deformed 12-phase ac plasma discharging device for waste disposal treatment and furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform detoxifying processing at an original generation point of a hazardous waste by efficiently utilizing generated heat energy by multi-phase multiple AC plasma discharge. <P>SOLUTION: With respect to a plasma furnace capable of performing a continuous operation for intensively heating a molten pool by combining two plasma discharge blocks one of which is a multi-phase plasma-jet flow and the other is a conventional plane plasma flow area, in a state of joining both plasmas to melt the waste to be melted by the molten pool disposed on a bottom portion of the furnace, incidental facilities are also loaded on a transporting vehicle with the furnace, so that the hazardous waste can be detoxified by a high temperature of plasma heat at the original generation point of the hazardous waste. The deformed 12-phase AC plasma discharge device and the furnace can be loaded on a moving medium. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a modified 12-phase AC plasma discharge apparatus and furnace for portable waste treatment. More specifically, the present invention efficiently concentrates the heat generated by the multi-phase plasma, melts glass, detoxifies and melts harmful difficult-to-treat artifacts such as asbestos, asbestos-containing materials, medical waste, and low-level radioactive waste. The present invention relates to a portable waste disposal apparatus and a furnace capable of volume reduction.

A plasma furnace that uses heat generated by plasma discharge generally uses a direct current as a power source, rectifies the alternating current, and employs a graphite electrode as an electrode. In recent years, the development of AC plasma furnaces has progressed, and attempts have been made to treat difficult-to-process artifacts. (For example, refer to Patent Document 1) An AC multiphase multi-plasma furnace for hazardous waste treatment can generate ultra-high temperatures with low-cost equipment, and the heat can be made harmless by melting and decomposition of difficult-to-process artifacts. Used. However, most of the heat generated by the plasma discharge is dissipated throughout the furnace by radiation and heat transfer, and when the difficult-to-process material is in the form of fine particles or mist, it melts within the transit time when falling from the top of the furnace to the bottom. It reaches the temperature and decomposition temperature and can be melted and decomposed. However, it is difficult to make such fine particles practically, and large particles cannot be completely melted.
The continuous operation is unknown.

Patent No. 3094217

In the present invention, in order to efficiently use the ultra-high temperature generated from the discharge plasma, the multi-phase vertical plasma jet flow from the upper part and the lower multi-phase planar plasma mass are orthogonal to each other, and the molten material containing the melt to be installed at the bottom is contained. To provide a modified 12-phase alternating current plasma discharge apparatus and a furnace for portable waste treatment, which heats a pond intensively, melts the melted material, discharges it over the weir, and discharges it outside the furnace. Objective.

In order to achieve this object, the invention according to claim 1 divides the 12-phase electrode into two blocks of 6 phases, and the upper 6-phase electrode is installed in the upper part of the furnace in a reverse truncated regular hexagonal pyramid shape. The 6-phase electrode is arranged horizontally or in a reverse slope from the apex of the regular hexagon toward the center of the regular hexagon, generating a 6-phase plasma jet flow downward from the upper electrode, and the lower electrode The multiphase planar plasma lump generated is combined, and plasma heat is concentrated in the molten pool of the invention according to claim 3, and the melted material is melted and discharged over the weir to the outside of the furnace.

The molten pool of the invention according to claim 3 is provided with a temperature sensor and is capable of temperature control, and has a cooling mechanism so that the temperature is not lower than the melting point of the melt and not higher than the softening point of the molten pool material. Has been.

When the electrode facing the center from the apex of the lower regular hexagon is placed horizontally, the gas density in the vicinity of the center of the discharge arc becomes low due to the high temperature and upwards. In order to prevent this state and efficiently concentrate heat in the molten pool, the electrodes are arranged so as to be inclined downward from the horizontal to the center as in the invention described in claim 4.

The electrode arranged on the upper portion as in the invention of claim 2 is a reverse melting regular hexagonal pyramid using a refractory metal or a graphite electrode, and the apex angle of the cone is preferably set at an acute angle of 5 to 40 degrees. An injection port is formed in an annular shape so that a gas for cooling is injected from the outer periphery in the vicinity of the electrode, and the injection port is further formed in a vortex shape as in the invention of claim 5. Add a twist angle. As a result, gas is injected while drawing a spiral and surrounding the plasma mass. When the cooling gas is mixed with an inert gas such as helium or argon and hydrogen, nitrogen, etc., the thermal pinch effect is enhanced. The inside of the furnace is sealed except for the cooling gas to prevent oxidation due to oxygen in the air, and to prevent excess gas from flowing in to increase thermal efficiency.

Since the electrode group arranged in the upper inverted truncated regular hexagonal pyramid shape as in the sixth aspect of the invention concentrates on one pole and reaches a high temperature, the electrode fixing device is provided with a cooling mechanism.

The multi-phase plasma jet ejected downward from the upper reverse-facing regular hexagonal pyramid-shaped electrode is cooled by the cooling gas, the multi-phase plasma jet contracts due to the thermal pinch effect, and the central portion is further heated. This multi-phase plasma jet and the multi-phase planar plasma mass generated by the lower discharge are combined, and the molten pool set at the bottom is heated intensively to melt the material to be melted efficiently. The molten slag is discharged outside the furnace over the weir of the molten pool.

As a method for exchanging the upper 6-phase electrode, each electrode is replaced with a collet as in the invention described in claim 7, the outer shell is a refractory sintered body having excellent electric resistance and heat resistance, and the multi-phase electrode is fixed. .

The plasma discharge apparatus and the furnace are portable so that the apparatus and the furnace can be loaded on a moving medium such as a vehicle. Therefore, the plasma discharge apparatus and the furnace are moved to a place where hazardous waste is generated as in the invention described in claim 8, and the detoxification process is performed. enable.

As in the ninth aspect of the present invention, the plasma discharge apparatus and the furnace have a structure in which the entire apparatus is sealed with a HEPA filter and is set at a negative pressure so that harmful substances are not discharged outside the apparatus.

As is apparent from the above description, the modified 12-phase AC plasma discharge apparatus and furnace for treating portable waste according to claim 1 is composed of two blocks of an upper 6-phase and a lower 6-phase, and the upper 6 phases are reversed. A multi-phase plasma jet flow is generated in a head-shaped hexagonal pyramid shape, and a multi-phase planar plasma mass generated by a lower discharge is united, and the molten material in the molten pool installed at the bottom of the furnace according to claim 3 It is possible to efficiently melt and discharge the melt outside the furnace.

Further, according to the deformable 12-phase alternating current plasma discharge apparatus and furnace for treating portable waste according to claim 4, since the lower electrode is inclined at the center, it is combined with the multiphase plasma jet from above, Thermal energy increases further and concentrates on the melt in the molten pool.

According to the modified 12-phase AC plasma discharge apparatus and furnace for treating portable waste according to claim 5, the multiphase plasma jet is concentrated downward by the cooling gas injected from the vicinity of the upper electrode.

According to the deformable 12-phase alternating current plasma discharge apparatus and furnace for treating portable waste according to claim 6, the upper electrode group becomes high temperature, and therefore the cooling mechanism is provided in the electrode fixing apparatus.

Further, according to the modified 12-phase alternating current plasma discharge apparatus and furnace for treating portable waste according to claim 7, each of the upper electrodes is a collet exchange system, and the exchange is easy and the outer shell is fixed by a refractory sintered body. .

Further, according to the modified 12-phase AC plasma discharge device and furnace for treating portable waste according to claim 9, the device and furnace are moved to a place where hazardous waste (asbestos, asbestos-containing material, etc.) is generated, and waste Processing is possible.

Further, according to the modified 12-phase alternating current plasma discharge apparatus and furnace for treating portable waste according to claim 10, the treatment apparatus is sealed and has a negative pressure while being equipped with a HEPA filter. Things are never discharged.

Further, according to the modified 12-phase alternating current plasma discharge apparatus and furnace for treating portable waste according to claim 11, organic substances, low-boiling substances, etc. are decomposed, vaporized, gasified, washed with a water scrubber, detoxified and put into the atmosphere. Discharged, washed water is stored, and it is processed at the final treatment plant, so no harmful substances are discharged.

Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

In the present invention, as a result of earnest examination on the problem of making slag and detoxifying hazardous waste (asbestos, etc.) using the high heat of the multi-phase multi-plasma generator, In order to enable melting, the multi-phase vertical plasma jet and the multi-phase planar plasma region are orthogonalized, and the resulting high heat has been successfully applied directly to the target material to be melted, thereby improving the thermal efficiency.

1 to 5 show an embodiment of the present invention. In the modified multi-phase multi-plasma discharge apparatus for waste treatment of this embodiment, the plasma mass generated from the multi-phase multi-plasma generator of FIG. 1 is as shown in FIG. Although explained, in actual arc generation, the atmospheric pressure drops due to high temperature, and the central part of the arc rises to the upper part. In such a situation, since it is arranged as multi-phase multiplex, the tendency further rises to the upper part. In actual measurement, the ratio of thermal energy between the upper part and the lower part is propagated at about 5: 1. In addition, it is considered possible to melt asbestos flying material in this multi-phase multi-plasma mass region. However, the actual waste appearance is more than 90% of the amount of cement and is made of paper and contains many solids. It has been found that a certain amount of heating time is required to melt them.

Therefore, it was devised to provide a molten pool as shown in Fig. 3-1. However, as described above, the plasma heat rises above the electrode, and only a few percent of heat energy is transmitted to the molten pool installed below the electrode. Furthermore, it has been found that the plasma heat is radiated at a high temperature of 4,500 k, so that it is also radiated to the side wall of the furnace. In order to solve these problems, we devised a multiphase plasma jet that uses the thermal pinch effect of the cooling gas, combined the jet flow with the lower multiphase planar plasma mass, and considered direct injection into the molten pool installed in the lower part. It was. Also, in the thermal pinch effect, the cooling gas is ejected in a spiral shape from the outer periphery of the multi-phase plasma, the plasma flows down in the vertical direction, and the outer envelope of the plasma is cooled, so that the plasma heat is compressed to the central part and to the inner wall of the furnace The amount of radiation is drastically reduced. As a result, the heat energy is concentrated in the lower molten pool and the thermal efficiency is improved.

FIG. 2 is a schematic diagram of a multiphase plasma jet mechanism, and an ejection hole through which inert gas, hydrogen gas, or the like is ejected on the outer periphery in the vicinity of the tip of an electrode 55 (refractory metal, graphite, or carbon electrode) disposed on a reverse truncated regular hexagonal cone 96 is provided in a spiral manner, and the electrode is held by a ceramic tube 56 having an inner diameter larger than the outer diameter of the electrode, and inert gas (nitrogen, argon, etc.) is ejected from the gap 99 to oxidize the electrode. To prevent. The electrode fixture 61 is made of stainless steel to hold the electrode on the inverted truncated regular hexagonal pyramid and for the purpose of cooling the tip, and a cooling water conducting tube 98 is formed in an annular shape in the vicinity of the tip of the electrode so that the cooling water is supplied. Pass water. These series of parts are fixed with a refractory sintered material in order to maintain the shape when the electrodes are replaced and to insulate with a high current. A 6-phase plasma jet nozzle having the specifications shown in FIG. The outer wall of the furnace is insulated with refractory bricks 83 and 75. When applied to the electrode of the upper multiphase plasma jet nozzle, a high frequency current is applied to one phase to generate plasma in six phases.

A multi-phase planar plasma electrode 72 is arranged in the lower stage, and planar plasma is generated by being applied together with one high-frequency power source. The generated flat plasma is caused to flow downward by combining the plasma lump that floats to the upper part due to the high-temperature plasma jet flow from the upper part. The combined upper and lower plasma energy directly hits the molten pool 85 disposed below the planar plasma electrode 72. The melting basin 85 is provided with a slag flow passage hole 86 for discharging slag, and is designed so that a molten pool temperature measuring element 84 is embedded in the vicinity thereof so that temperature control is possible at all times, and the slag outflow temperature is controlled. To do. When the temperature increases, the amount of melt input increases, and when the temperature decreases, the amount of melt input decreases. It is also possible to change the current applied to the electrode, and a constant melt (slag) can be obtained at all times.

Furthermore, there are flying objects in the micron level in the waste, and it is mixed with the material to be melted from the upper part and put into the furnace, but the plasma heat is concentrated in the lower molten pool 85 and the central part. However, the inert gas (nitrogen, argon, etc.) and the hydrogen gas, etc. that have flowed into the multi-phase plasma jet expand due to heat. The expanded gas is concentrated in the slag flow road hole 86, and the vicinity thereof also serves as a hot gas flow road. Therefore, the flying object that flows into the flowing gas completely melts. The relatively large melt of the molten material that has been thrown in is heated even when the plasma region falls, but most of the molten material is buried in the hot water pool of the molten pool 85 in an unmelted state and exceeds the melting point of the molten material. The unmelted solid is heated by the controlled heat of the molten pool to increase the melting efficiency. The molten material flows over the weir of the molten pool and flows out of the furnace.

Other plasma furnaces specially heat the current road, plasma melting furnaces using DC as the power source place a metal electrode at the bottom of the molten pool as the anode of the electrode, and soot graphite etc. at the bottom of the furnace when plasma is generated Without this treatment, it is difficult to ignite the plasma, and it takes a lot of labor when the plasma is extinguished when the melt is charged. The plasma generated by the high-frequency ignition of the multiphase electrode of the present invention is continuously generated without extinguishing the plasma, and the plasma heat is at the bottom by orthogonality of the multiphase plasma jet from the top and the planar multiphase plasma mass at the bottom. The energy will concentrate on the molten pool 85.

A small melting furnace having a mechanism for orthogonally crossing the multiphase plasma jet and the multiphase planar plasma mass is mounted on a truck as an example of a moving medium as shown in FIG. For the purpose of preventing secondary pollution from occurring, the generator 4 is permanently installed on the loading platform, moved to the place where hazardous waste is generated, and the hazardous waste is detoxified. In addition, the internal pressure is negative, and when the material to be melted is large, the crusher 29 loaded truck as shown in FIG. Is provided with a retractable passage 28, which is used as a security zone and does not discharge hazardous waste to the outside. In addition, a bellows passage 27 is installed at the rear of the truck loaded with the crusher 29 in FIG. 4 and is connected to the waste discharge site so that a negative pressure is sealed.

The lid 31 at the end of the crusher 29 is opened when the object to be crushed is charged, and a bumper 33 is opened at the top in conjunction with the crusher 29 and placed in the guide chute hopper 32. When the material to be crushed is charged, the damper 33 is closed, and the hopper 32 circulates to the upper part of the crusher, reaches the top of the crusher, the bottom plate 34 of the hopper 32 opens, and the material to be crushed falls inside the crusher. The material to be crushed is crushed by the cutter rotor 36 and the cutter fixed blade 37 and classified by the mesh 38. The classified material to be crushed is moved to the joint 40 by the lower screw conveyor 39 and further melted by the transfer pipe 41 in FIG. It is transferred to the melted material hopper 24 of the furnace loading truck. The melted material temporarily placed in the hopper 24 is transferred to the melted material charging device 1 (screw conveyor) 17 directly connected to the furnace by the molten material charging device 2 (screw conveyor) 18, measured, and charged into the furnace. . The crusher 29 is completely sealed from the charging of the crusher 29 to the melting furnace, and further, it is completely sealed by the folding outer wall 20 of the truck in which those facilities are installed to prevent secondary disasters. Each truck is provided with negative pressure dust removing devices 13 and 47, and HEPA filters are set in the passages to prevent discharge to the outside even when the filters are replaced.

Various gases are expected to be generated in the melting furnace 1, but the gas discharged from the processing chamber waste blower 13, the negative pressure dust removal device 13 and the negative pressure dust removal device 47 is washed with water by the booth 44 and discharged into the atmosphere. The The water used here is supplied from a treated water tank (water supply) 52, and the used wastewater is stored in the treated water tank 52 (drainage) and processed at a terminal treatment plant.
These series of processes are performed in a completely sealed negative pressure apparatus.

The present invention is used for the detoxification treatment of hazardous wastes that require a particularly high temperature treatment, and is used for glass solidification detoxification of asbestos, asbestos-containing slate, incinerator ash, medical waste, etc.
It is useful as a low energy and environmentally friendly treatment method.

Specification of Japanese Patent No. 3094217, description of the difference between the position of the double electrode in the high-temperature plasma region and the temperature distribution in the region when plasma is generated with multi-phase double. It is a figure which shows the three-phase alternating current multiphase plasma jet mechanism of this invention. It is a figure which shows the general view, front view, side view, and form figure which show the combination discharge mechanism of planar multiphase plasma and a vertical multiphase plasma jet. A schematic diagram of a portable waste disposal truck 2 (for pretreatment) is shown. Schematic of portable waste disposal truck 1 (for melting treatment) is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Melting furnace main body 2 Electrode feeder 3 Multiphase 6 phase plasma jet main body 4 Generator 5 Control panel 6 Transformer 7 Nitrogen gas cylinder 8 Hydrogen gas cylinder 23 Melting material inlet 29 Crusher 52 Treated water tank

Claims (11)

In a plasma melting furnace, a three-phase AC power source or a three-phase AC power source of a simple generator is used, and a transformer is combined so that it becomes 12 phases. Is arranged in the upper part of the furnace in a reverse truncated regular hexagonal pyramid shape, and the remaining one block of 6-phase electrodes is horizontally arranged in the lower stage, or arranged in a form inclined from the apex of the regular hexagon toward the center of the regular hexagon in the reverse direction, A six-phase plasma jet is generated downward from the upper truncated regular hexagonal pyramidal electrode, while a multiphase planar plasma is directed toward the center of the regular hexagon from the lower hexagonal apex toward the center. The two plasma lumps collide with each other, and the two plasma lumps are combined and the plasma arc heat is concentrated below the lower electrode position. 12 AC plasma discharge apparatus and furnace. In the plasma melting furnace, the electrode configuration at the top of the furnace is sealed except for the injection of cooling gas (inert gas, hydrogen gas, etc. alone or mixed gas) that is injected from the outer periphery near the tip of the inverted truncated regular hexagonal pyramid electrode. A modified 12-phase AC plasma discharge apparatus and furnace for portable waste treatment, wherein gas other than the gas mixed in the melted material does not enter or exit from the inlet of the melted material. In the plasma melting furnace, a molten pool is provided near the bottom of the electrode from the top of the lower regular hexagon toward the center, and the molten pool is equipped with a temperature sensor and a cooling mechanism, and temperature control is possible. The melted material is heated and insulated by the convection heat of the phase plasma jet, and the melted material is heated and kept warm, and the unmelted material dropped from the top is completely melted and slagged. A modified 12-phase AC plasma discharge apparatus and furnace for portable waste treatment, characterized in that it can be discharged to The electrode group from the apex of the lower regular hexagon toward the center is arranged horizontally, but the discharge arc is directed upward due to the high temperature particularly in the vicinity of the center of the regular hexagon. Therefore, a deformable 12-phase alternating current plasma discharge apparatus and furnace for treating portable waste, characterized in that hexapoles are arranged in advance so that the axis of the electrode is inclined in front of the center of the regular hexagon. An electrode in which one block of 6-phase electrodes is arranged in a reverse-facing regular hexagonal pyramid shape uses a refractory metal or graphite electrode, protrudes from the apex of the regular hexagon, and has a cooling gas (inert gas, hydrogen gas, etc.) around its periphery. (Single or mixed gas) The injection hole may be formed in an annular shape, and the shape of the injection hole may be a straight hole, but the twisted angle is set so that the injected gas becomes a vortex, and the injected gas draws a spiral while drawing a plasma. Siege and erupt. Also, this jet hole has a twisted angle in the same direction as the rotation direction of the multi-phase plasma ignition, and a deformed 12-phase plasma torch-like portable waste treatment drilled in a conducting ring formed in an annular shape. AC plasma discharge furnace. An electrode group in which one block of 6-phase electrodes are arranged in a reverse truncated regular hexagonal pyramid shape is concentrated in one pole, so high heat is accumulated, and a hole for cooling is connected to the electrode fixture in an annular shape. A modified 12-phase AC plasma discharge apparatus and furnace for portable waste treatment, characterized by opening a hole, passing cooling water, and cooling. An electrode group in which one block of six-phase electrodes is arranged in a reverse truncated regular hexagonal pyramid shape is concentrated in one pole, and a high current passes through the six-phase electrodes. As an easy method for electrode replacement, each electrode is a collet replacement system, and its outer shell is a refractory fired / sintered body, and a plasma torch shape that employs a multiphase electrode fixing method that contributes to electric resistance and heat resistance. Modified 12-phase AC plasma discharge apparatus and furnace for portable waste disposal. The plasma melting furnace moves to the place where hazardous waste (asbestos and asbestos-containing materials, etc.) is generated, and is a modified 12-phase AC plasma discharge device and furnace for portable waste treatment that enables detoxification treatment. Hazardous waste plasma melting furnace and processing equipment are sealed, and the inside of the equipment is set to negative pressure. The negative pressure equipment is equipped with High Efficiency Particulate Air Filter (commonly called HEPA filter). In addition, a modified 12-phase AC plasma discharge device and furnace for portable waste disposal, characterized in that no harmful substances are discharged outside the vehicle. The moving medium is limited in size and has a plurality of portable machines. The plurality of moving media are connected by a movable passage that can be expanded and contracted (for example, bellows, accordion, etc.), and the space is used as a security zone. . Hazardous gas generated in the treatment of hazardous waste is washed with a water scrubber, detoxified gas is discharged into the atmosphere, and the wash water is stored in a treatment tank and processed at a final treatment plant. A modified 12-phase AC plasma discharge apparatus and furnace for portable waste treatment.

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