KR102003277B1 - Plasma melter for treatment of low- and intermediate-level radioactive waste - Google Patents

Abstract

The present invention relates to a plasma melting device having an inputting device capable of facilitating inputting and treating of drum type radioactive waste and preventing leakage of harmful substances from the outside while treating the radioactive waste. The present invention relates to a plasma melting device for treating intermediate/low level radioactive waste comprising a reactor (100) and the inputting device (200). The reactor (100) includes a thermal decomposition room (101) and a melting room (102) having a first plasma torch (110). The inputting device (200) inputs a waste drum to the thermal decomposition room (101). The inputting device (200) includes a slope inputting unit (210), a heat emitting body (220), a rotating gate (230), a second plasma torch (240), and a controlling unit (300). The slope inputting unit (210) includes an inputting channel (211) and a door (212), and inputs the waste drum (10). The inputting channel (211) is adjacent to the thermal decomposition room (101) and is provided in a side part of the reactor (101) with a slope having a predetermined angle. The door (212) is provided in an entrance of the inputting channel (211), and is opened and closed. The heat emitting body (220) is provided in the inputting channel (211) and emits heat. The rotating gate (230) is positioned in a front end of the inputting channel (211), rotates a plurality of wings to block the inputting channel (211), and inputs the waste drum (10) to the thermal decomposition room (101) by one waste drum (10) unit. The second plasma torch (240) is adjacent to the rotating gate (230) and crushes the waste drum (10). The controlling unit (300) controls temperature of the heat emitting body (220) and controls rotation driving of the rotating gate (230).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a plasma melting apparatus for low- and intermediate-level radioactive waste treatment,

The present invention relates to a plasma melting apparatus for the treatment of medium and low level radioactive waste, and more particularly, to a plasma melting apparatus for efficiently and efficiently controlling the introduction of drum type radial wastes while discharging harmful substances such as radioactive substances, The present invention relates to a plasma melting apparatus having a drum type radioactive waste input device capable of preventing a radioactive waste.

There are about 430 nuclear power stations in operation around the world, and there are 26 commercial nuclear power plants scheduled to be operated, constructed and built in Korea. The wastes generated during the operation and maintenance of these power plants are classified into high level and low level wastes depending on the intensity of radioactivity. Most of high level wastes are wastes which refer to spent fuel. In contrast, low-level wastes are low-level radioactive wastes, including waste filters used in ventilation systems in nuclear power plants, ion exchange resins in the treatment of contaminated water, concentrated wastes, work clothes or gloves used by workers, Such as dirt, dirt, and tools. Radioactive waste from industries, hospitals and research institutes using radioactive isotopes is also classified as low-level waste.

These wastes contain radioactive nuclides such as cesium-137 and cobalt-60, so after about 300 years, the radioactivity risk disappears. Therefore, it is usually subjected to compression incineration treatment, followed by solidification with concrete or concrete, etc., . However, since the storage capacity is limited, the method of stabilizing the radioactive waste to minimize the amount of stored waste is one of the main policies of the medium and low-level waste management policy. In addition, nuclear power plants that have reached the end of their life will be demolished for a long period of time. The wastes generated during dismantling are cement, concrete, contaminated soil and various kinds of metals. Therefore, they should be managed for a long time It is very important to treat wastes as soon as possible, environmentally friendly, stable and economically.

The low-level waste generated during the operation and dismantling of nuclear power plants in Korea is divided into combustible and non-combustible wastes. Non-combustible materials include concrete, steel, glass, filter, and soil. Flammable materials include protective clothing, gloves, mask, paper, Wastewater, PVC, and vinyl sheets. The wastes generated in the nuclear power plants are processed in such a way that they are put into a drum, compressed, cured with cement, or stored in a container after drying.

As one of the methods for solving the problems in the treatment of radioactive waste, there is proposed a plasma method in which wastes composed of various components of organic matter and inorganic matter are simply treated by using hot thermal energy. Plasma equipment for treating wastes includes a reactor consisting of a preheating or pyrolysis chamber, a melting chamber, a secondary combustion chamber and a waste input device attached to the reactor, a plasma torch, a slag and a metal outlet generated after the treatment, , Bag filter, heat exchanger, etc., it is important to operate smoothly and stable operation of these devices, and to consider the economical efficiency and efficiency of the process operation. Among them, the safety of the facility operator and the surrounding environment is the most important factor in the facility for treating radioactive waste.

Patent Registration No. 10-1379443 (Publication Date: April 4, 2014)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art, and it is an object of the present invention to provide an apparatus and a method for efficiently controlling the introduction of drum type radial waste into a reactor, Which can prevent leakage of the radioactive waste to the plasma processing apparatus.

In order to achieve the above object, there is provided a plasma melting apparatus for a low-level radioactive waste treatment (hereinafter abbreviated as "melting apparatus") according to the present invention comprises a pyrolysis chamber in which pyrolysis and preheating of radioactive waste are performed, and a first plasma torch, A reaction furnace including a melting chamber for melting the radioactive waste put into the chamber; And a charging device for introducing a waste drum into the pyrolysis chamber, wherein the charging device comprises a pyrolysis chamber having a pyrolysis chamber and a pyrolysis chamber, A slope input unit having a channel and a door capable of being opened and closed at an inlet of the input channel to input a waste drum; A heating element provided on the input channel to generate heat; A rotatable gate located at the tip of the charged channel and having a plurality of blades rotatable to block the charged channel, the waste drum being charged into the pyrolysis chamber in units of one waste drum; A second plasma torch provided adjacent to the rotatable gate for cutting the waste drum; And a controller for controlling the temperature of the heating element and controlling the rotational driving of the rotary gate.

Preferably, the apparatus further includes a rotation speed detection unit for detecting the rotation speed of the rotation type gate and transmitting the detection signal to the control unit.

More preferably, the rotational speed detecting portion includes a plurality of limit switches disposed on an outlet side of the closing channel and capable of detecting a rotational vane of the rotational gate.

Preferably, the heating element is divided into a plurality of sections so as to have a high temperature gradient in the inlet direction of the pyrolysis chamber.

The present invention includes a charging device having a slope at a predetermined angle on a sidewall of a reactor furnished with a thermal decomposition chamber and a melting chamber, and a waste drum is charged. The charging device has a door that can be opened and closed at the inlet of the charging channel. A rotary type gate which is capable of continuously injecting a waste drum into the outlet side while spatially blocking an input channel and a plasma torch which is adjacent to the rotary type gate to cut the waste drum, And the inside and the outside of the reaction furnace are blocked by the door and the rotation type gate so that harmful substances such as radioactive substances generated in the reaction furnace during the melting process of the waste can be prevented from being dispersed and released to the outside There is an effect.

Brief Description of Drawings Fig. 1 is an overall configuration diagram of a melting apparatus according to an embodiment of the present invention,
FIG. 2 and FIG. 3 are enlarged views of a charging apparatus in a melting apparatus according to an embodiment of the present invention;

The specific structure or functional description presented in the embodiment of the present invention is merely illustrative for the purpose of illustrating an embodiment according to the concept of the present invention, and embodiments according to the concept of the present invention can be implemented in various forms. And should not be construed as limited to the embodiments described herein, but should be understood to include all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Meanwhile, in the present invention, the terms first and / or second etc. may be used to describe various components, but the components are not limited to the terms. The terms may be referred to as a second element only for the purpose of distinguishing one element from another, for example, to the extent that it does not depart from the scope of the invention in accordance with the concept of the present invention, Similarly, the second component may also be referred to as the first component.

Whenever an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but it should be understood that other elements may be present in between something to do. On the other hand, when it is mentioned that an element is "directly connected" or "directly contacted" to another element, it should be understood that there are no other elements in between. Other expressions for describing the relationship between components, such as "between" and "between" or "adjacent to" and "directly adjacent to" should also be interpreted.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. It will be further understood that the terms " comprises ", or "having ", and the like in the specification are intended to specify the presence of stated features, integers, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is an overall configuration view of a plasma melting apparatus for the treatment of medium and low level radioactive waste according to an embodiment of the present invention. FIGS. 2 and 3 are enlarged views of a charging apparatus in a melting apparatus according to an embodiment of the present invention.

1 to 3, a plasma melting apparatus according to the present invention includes a thermal decomposition chamber 101 in which thermal decomposition and preheating of a radioactive waste is performed, a radioactive waste which is provided in the thermal decomposition chamber 101 and provided with a first plasma torch 110, And a melting furnace 102 in which a melting process is performed by the melting furnace 102. The reactor 100 includes a charging device 200 for charging the waste drum 10 into the pyrolysis chamber 101 do.

As the reactor 100, a material excellent in heat resistance and heat insulation such as heat-resistant bricks and adiabatic bricks is used, and a metal material for structural reinforcement can be used together.

Preferably, the reactor 100 includes a pyrolysis chamber 101 and a fusing chamber 102 having a vertical structure, the pyrolysis chamber 101 is preheated, and the fusing chamber 102 In the pyrolysis chamber (101), the preheated radioactive waste is subjected to a melting treatment. In the vertical reactor 100, the pyrolysis chamber 101 forms a vertical upper space of the fusing chamber 102, and the horizontal cross-sectional area of the pyrolysis chamber 101 is smaller than that of the fusing chamber 102.

The first plasma torch 110 is installed on top of the melting chamber 102 to provide melting heat for melting the waste. The first plasma torch 110 may be provided by a dual plasma torch capable of a transfer type or a non-transfer type operation. The first plasma torch 110 may be provided with a joule heat generated by the bottom electrode 111 provided under the melting chamber 102, And the torch frame temperature and arc heat can be used to maximize the melting efficiency.

The melting chamber 102 is provided with a hearth 111 in which melts are received and a bottom electrode 112 provided at the bottom of the furnace 111 to form a first plasma torch 110 and a bottom electrode 112, The waste is melted and separated into the slag layer 11 and the metal layer 12 by the specific gravity difference.

The reaction furnace 100 is provided with a slag outlet 120 through which the slag is discharged and a metal outlet 130 communicating with the bottom of the furnace 111 and discharging the metal.

The slag outlet 120 is provided on one side of the lower portion of the melting chamber 102 to overflow the side wall of the lower portion of the melting chamber 102 when the slag is generated above a certain level, 100). The waste is continuously melted and the slag is accumulated in the slag layer 11 and then continuously discharged through the slag outlet 120, which is loaded into the slag container. On the other hand, the molten metal flows into the metal layer 12, is concentrated to a certain level, is discharged to the outside through the metal outlet 130 intermittently, and is stored in a separate metal container.

Although not shown, an exhaust gas treatment facility may be added to the upper part of the reaction furnace 100 to connect the pyrolysis chamber 101 to secondary combustion of the exhaust gas generated in the reaction furnace 100 to collect dust. The flue gas treatment facility removes the harmful components by passing the flue gas through the washing tower after the flue gas is secondarily combusted, and after passing through the condenser, dryer, dust collector, etc., water and dust are removed and then discharged to the outside.

Reference numeral 140 denotes a surveillance camera to monitor the melting process of the reactor 100. The surveillance camera may be provided at a plurality of positions in the reactor 100 to observe the melting process from the outside. In addition to this surveillance camera, the reactor can be provided with a separate window for directly observing the inside of the reactor.

The low-level waste generated in nuclear power plants is stored in a 200L drum container and the waste stored in the drum is collected and stored in various forms such as flammable and inorganic wastes. Therefore, since the radioactive waste stored in the 200 L drum is likely to be contaminated by secondary pollution, it is difficult to separate and treat it separately. Therefore, a series of stabilization treatments such as injection, crushing, combustion and melting of waste are continuously performed in one reactor It is very important. Therefore, in the present invention, the waste drum moved from the reservoir is put into the reactor 100 as it is in a circular shape, and is melt-processed without further operation, and finally disposed.

Specifically, the charging device 200 includes a charging channel 211 provided adjacent to the thermal decomposition chamber 101 for charging the waste drum 10 and a door 212 provided at the inlet of the charging channel 211 to be openable and closable A heating body 220 provided in the charging channel 211 to heat the waste charging section and a rotatable gate 230 rotatable at the leading end of the charging channel 211, And a control unit 300 for controlling the driving of the heating element 220 and the rotation type gate 230.

The injector 200 can be detachably attached to the reactor 100 and can be replaced with an injection channel 211 having a different length depending on the type and content of the waste, Replacement can be made with the supplied dosing device.

The inclined charging unit 210 includes a charging channel 211 provided at the side of the reactor 100 with a predetermined angle of inclination and a door 212 provided at the entrance of the charging channel 211 to be openable / . The inlet channel 211 is provided at the side of the reactor 100 with a slope of 5 to 20 ° so that the charged waste drum 10 is smoothly moved to the pyrolysis chamber 101 along the inlet channel 211.

The door 212 is provided on the inlet side of the intake channel 211 and is preferably provided by a sliding type door that is opened and closed in the vertical direction for rapid opening and closing. The open / close portion of the door 212 may be provided with a known airtight member having excellent heat resistance that can prevent the gas generated inside the reaction furnace 100 from being discharged to the outside. Such a hermetic member may deteriorate cooling or jacket cooling cooling jacket may be added to prevent degradation of the cooling jacket.

The heating element 220 is arranged along the charging channel 211 to heat the moving section of the waste drum 10 and can be provided by a hot wire wound around the charging channel 211. The temperature of the heating element 220 is controlled by the controller 300.

The control unit 300 may include a first controller 311 for controlling the power applied to the heating element 220 and a PC 320 for controlling the first controller 311. In addition, the PC 320 is connected to the monitor 330, and the detected temperature of the input channel 211 can be output in real time through the monitor 330. [

Preferably, the heating element 220 is divided into three or more sections A, B, and C on the inlet channel 211, and the temperature rises as it approaches the inlet of the pyrolysis chamber 101. The internal temperature of the inlet channel 211 is preheated with a temperature gradient in the range of 200 ° C to 800 ° C, and temperature control is performed according to the type and condition of the waste.

The rotary gate 230 is disposed at the distal end of the charging channel 211 and is rotatably provided with a plurality of rotary vanes to block the charging channel 211. In this rotary type gate 230, one waste drum 10 is seated between rotary blades, and the waste drum 10 is put into the thermal decomposition chamber 101 in units of one waste drum 10, The typical gate 230 divides the space between the pyrolysis chamber 101 and the charging channel 211 so that the waste drum 10 is continuously introduced into the pyrolysis chamber 101 and is generated inside the reaction chamber 10 Thereby preventing the emitted substance or gas from being discharged to the outside.

A second plasma torch 240 is disposed within the reactor 100 adjacent to the rotatable gate 230 and a second plasma torch 240 is disposed within the pyrolysis chamber 101 while being rotated by the rotatable gate 230. [ The waste drum 10 cut by the second plasma torch 240 and the wastes in the waste drum 10 fall down toward the bottom of the melting chamber 102, And a melting process is performed.

Preferably, the rotatable gate 230 is actively rotationally driven by the controller 300, the controller 300 includes a drive unit (not shown) for driving the rotatable gate 230, And a second controller 312 is connected to the PC 320 and the monitor 330. The second controller 312 is connected to the PC 320 and the monitor 330. [

The reaction furnace 100 is provided with a plurality of limit switches 251 capable of detecting the rotary vane of the rotary gate 230 at the outlet side of the input channel 211. The limit switch 251 is connected to the rotary gate 230 and transmits the detection signal to the PC 320 via the third controller 313. The PC 320 counts the detection signals of the rotary blades and calculates the rotation speed of the rotary blades. The rotation speed of the rotatable gate 230 calculated in this manner is output through the monitor 330.

Although the rotation speed of the rotation type gate 230 is calculated by the control unit 300 using the detection signals of the plurality of limit switches in the present embodiment, the rotation speed is not limited to this, May be provided by a known sensor such as an encoder that is attached to the rotating shaft and detects the rotating speed of the rotating shaft.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be apparent to those of ordinary skill in the art.

100: reactor 101: pyrolysis chamber
102: melting chamber 110: first plasma torch
200: input device 210: inclined input part
211: input channel 212: door
220: heating element 230: rotatable gate
240: second plasma torch 251: limit switch
300: control unit 311: first controller
312: second controller 313: third controller
320: PC 330: Monitor

Claims (4)

A reaction furnace including a pyrolysis chamber in which pyrolysis and preheating of the radioactive waste is performed, and a melting chamber in which a first plasma torch is provided and the radioactive waste injected into the pyrolysis chamber is melted; And a charging device for charging a waste drum into the pyrolysis chamber, the plasma melting apparatus comprising:
The charging device includes:
An incinerator having an inlet channel provided at a side of the reaction chamber adjacent to the pyrolysis chamber and having an inclination at a predetermined angle and a door capable of being opened and closed at the inlet of the inlet channel to introduce the waste drum;
A heating element provided on the input channel to generate heat;
A rotatable gate located at the tip of the charged channel and having a plurality of blades rotatable to block the charged channel, the waste drum being charged into the pyrolysis chamber in units of one waste drum;
A second plasma torch provided adjacent to the rotatable gate for cutting the waste drum;
A control unit for controlling the temperature of the heating element and controlling the rotational driving of the rotary gate;
And a rotation speed detector for detecting a rotation speed of the rotary gate and transmitting a detection signal to the controller,
Wherein the rotation speed detecting unit includes a plurality of limit switches disposed on an outlet side of the closing channel and capable of detecting a rotating blade of the rotating type gate. delete delete The plasma melting apparatus according to claim 1, wherein the heating element is divided into a plurality of sections so as to have a high temperature gradient in the inlet direction of the thermal decomposition chamber.

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