Apparatus for loading heating element for vitrification melting furnace

Abstract

Disclosed is an apparatus for loading a heating element for heating molten glass, in order to restart a vitrification melting furnace, for vitrifying radioactive waste, when the vitrification melting furnace has an emergency shutdown. The apparatus for loading a heating element for a vitrification melting furnace, according to one embodiment of the present invention, is for loading a heating element into a glass melting furnace for vitrifying radioactive waste, and may comprise: a main frame; a universal joint positioned on one end of the main frame; at least one heating element coupling part rotatably connected to the universal joint; and a gripper positioned on an end of the heating element coupling part so as to grab a heating element.

Description

Glass melting furnace heating element charging device

[0001] The present invention relates to a device for loading a heating element for heating molten glass in order to restart a vitrification furnace for vitrifying radioactive waste in the event of an emergency stop of the furnace.

[0002] Radioactive waste generated from nuclear power plants and facilities utilizing radioactive isotopes must be disposed of safely. Radioactive waste is classified into low- and intermediate-level waste (LILW) and high-level waste (HILW) based on its radioactivity. Low- and intermediate-level waste primarily consists of waste generated during nuclear power plant operation, such as filter media, ion exchange resins, condensed residue from waste liquid evaporators, and miscellaneous items such as work clothes, tools, and tissues used by radiation workers.

[0003] Low- and intermediate-level radioactive wastes such as this are mixed with a solidifying agent such as cement or paraffin, sealed in a waste drum, and then solidified or compressed and sealed in a waste drum, and stored in a safe place such as a waste management facility. However, the installation and maintenance of waste management facilities not only require a considerable amount of manpower and cost, but also face many difficulties in installing the facilities due to social avoidance, and this is emerging as a serious social problem.

[0004] Meanwhile, technologies for processing low- and intermediate-level radioactive waste include combustion and pyrolysis, followed by vitrification, which melts the waste together with glass at high temperatures to create a solidified glass. This vitrification technology for low- and intermediate-level radioactive waste not only dramatically reduces the amount of waste but also permanently prevents radioactive leakage.

[0005] In the early days of vitrification in a vitrification furnace for vitrification of radioactive waste, workers directly loaded the heating element without a separate device, but it was difficult for workers to work closely in an environment with radioactive waste in an emergency.

[0006] In the event of an emergency stop of the glass melting furnace, the glass inside the glass melt was completely removed and the vitrification process was restarted, so there was a risk of radiation exposure or accidents to workers during glass removal.

[0007] During the vitrification process, a heating element (Ti-ring) is inserted into the furnace to generate heat and oxidize the molten glass. During the radioactive waste treatment process, if an emergency shutdown occurs, the internal molten glass cools, requiring the addition of additional heating elements to restart the furnace.

[0008] Accordingly, the present invention is intended to solve the above-described problem, and provides a device for heating a glass melt, which can perform a restart operation in a state where the internal glass is solidified without glass removal operation in the event of an abnormal stop, by utilizing a device for loading a heating element.

[0009] The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

[0010] A heating element loading device for a glass melting furnace according to an embodiment of the present invention for achieving the above task is configured to load a heating element into a glass melting furnace for vitrifying radioactive waste, and may include a main frame, a universal joint positioned at one end of the main frame, at least one heating element fastening part that is connected to and rotates with the universal joint, and a gripper positioned at an end of the heating element fastening part for holding the heating element.

[0011] The above gripper may include a support portion and a grip portion connected to the support portion.

[0012] The gripping portion may include a first finger portion, a second finger portion coupled to the first finger portion, a first joint coupling the first finger portion and the second finger portion, and a second joint coupling each of the first finger portion and the second finger portion to the support portion.

[0013] The device may further include a control wire connected to the first joint and controlling the movement of the first finger portion and the second finger portion so that the first finger portion and the second finger portion grip the heating element or release the grip of the heating element.

[0014] The above control wire may further include a control unit positioned at the other end of the main frame to control the release and fixation of the control wire.

[0015] It may further include a reference part that is positioned to slide on the main frame and controls the behavior of the heating body fastening part.

[0016] When the above reference part slides in the direction of the above one end of the main frame, the heating body fastening part can be rotated away from the main frame.

[0017] When the above reference part slides in a direction opposite to the above end of the main frame, the heating body fastening part can be rotated to approach the main frame.

[0018] Specific details of other embodiments are included in the detailed description and drawings.

[0019] According to the present invention, a device for loading a heating element for heating a glass molten metal is provided, which can perform a restart operation in a state where the internal glass is solidified without a glass removal operation in the event of an abnormal stop by utilizing a device for loading a heating element.

[0020] Figure 1 illustrates a glass melting furnace heating element loading device according to an embodiment of the present invention.

[0021] Figure 2 illustrates a gripper of a glass melting furnace heating element loading device according to an embodiment of the present invention.

[0022] Figure 3 illustrates the operation of the reference part of the glass melting furnace heating element loading device according to an embodiment of the present invention.

[0023] Figure 4 illustrates loading a heating element into a glass melting furnace using a heating element loading device according to an embodiment of the present invention.

[0024] The present invention relates to a device for loading a heating element into a glass melting furnace for vitrifying radioactive waste, comprising: a main frame; a universal joint positioned at one end of the main frame; at least one heating element fastening member that is connected to and rotates with the universal joint; and a gripper positioned at an end of the heating element fastening member and that grips the heating element.

[0025] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. The advantages and features of the present invention, and methods for achieving them, will become clear with reference to the embodiments described in detail below together with the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

[0026] Hereinafter, a glass melting furnace heating element loading device according to an embodiment of the present invention will be described.

[0027] FIG. 1 illustrates a heating element loading device for a glass melting furnace according to an embodiment of the present invention, FIG. 2 illustrates a gripper of a heating element loading device for a glass melting furnace according to an embodiment of the present invention, FIG. 3 illustrates the operation of a reference part of a heating element loading device for a glass melting furnace according to an embodiment of the present invention, and FIG. 4 illustrates loading a heating element into a glass melting furnace using a heating element loading device for a glass melting furnace according to an embodiment of the present invention.

[0028] Meanwhile, the vitrification treatment system for radioactive waste is a facility that processes radioactive waste more safely. Not only can it drastically reduce the volume of low- and intermediate-level radioactive waste, but it can also minimize the leakage of radioactive materials into the surroundings in any environment, thereby significantly improving the safety of radioactive waste treatment.

[0029] Vitrification systems for radioactive waste not only fundamentally prevent the release of radioactive materials into the environment by binding radioactive waste to a glass structure, but also dramatically reduce the volume of radioactive waste. Vitrification technology can reduce the initial volume of all combustible and non-combustible low- and intermediate-level radioactive waste generated from nuclear power plants by more than 1 / 20th. This will significantly contribute to ensuring the safety of radioactive waste disposal and to the stable implementation of disposal projects for management facilities.

[0030] The radioactive waste vitrification treatment system can vitrify radioactive waste through the following process.

[0031] Glass raw materials are placed in an induction-heated vitrification furnace, and the heat induced by an electromagnetic field melts the glass. Once molten glass is produced at approximately 1,100°C, finely crushed waste stored in the radioactive waste storage facility is fed into the molten glass through a radioactive waste feeder. This causes the waste to decompose, and the radioactive materials are firmly bonded to the glass components. Combustible waste that can be processed in an induction-heated vitrification furnace includes clothing, gloves, shoes, and tissues used by workers, as well as low-radioactive waste resins used for water purification at nuclear power plants.

[0032] Radionuclides formed within the glass structure are unable to escape under any environmental conditions. This robustness of the bond between the glass structure and radionuclides is confirmed through internationally recognized leaching tests.

[0033] The glass molten metal in the vitrification furnace can be produced as follows. That is, the initial ignition method of glass for vitrification in a low-temperature melting furnace for the treatment of low- and intermediate-level radioactive waste is performed as follows. In order to produce the glass molten metal before the waste is fed, a certain amount (for example, approximately 60 kg) of glass raw material (glass frit) is first filled into the inner space (for example, 55 cm in diameter) of the vitrification furnace, and a titanium metal ring with a certain diameter (for example, 36 cm in inner diameter and 38 cm in outer diameter) is inserted into the solid glass raw material at a certain height (for example, 16 or 18 cm) from the bottom of the vitrification furnace.

[0034] In this state, by gradually increasing the output of the high frequency generator and generating an electromagnetic wave from an inductor surrounding the vitrification furnace and concentrating it on the titanium metal ring (5), an induced current is generated in the titanium metal ring (5), and the induced current is ignited at a certain point of the titanium metal ring (5) where the highly concentrated electromagnetic wave is concentrated.

[0035] In this way, the thermal and electrical energy generated from the titanium metal ring (5) is transferred to the glass to ignite and melt the glass. The situation at the time of ignition can be known through visual observation, but it can also be easily known through the changes in the input voltage and current flowing into the low-temperature vitrification furnace. Before the titanium metal ring (5) ignites, the voltage and current increase in a gentle upward curve, but at the moment of ignition, the voltage drops sharply and the current, conversely, rises sharply as the physical properties of the glass change. Through this process, molten glass can be formed by the heating element (5) loaded into the vitrification furnace. The heating element (5) is oxidized and cannot be reused.

[0036] Meanwhile, during the process of processing radioactive waste, a situation may arise where a vitrification furnace or the like suddenly stops. If a vitrification furnace suddenly stops, the molten metal inside the vitrification furnace cools down, requiring the installation of an additional heating element to melt the molten metal before restarting. The present invention relates to a device for installing a heating element inside a vitrification furnace so that the molten metal inside the vitrification furnace can be reheated when the vitrification treatment system suddenly stops during the vitrification process.

[0037] Referring to FIG. 1, a heating element loading device (10) for a glass melting furnace according to an embodiment of the present invention is for loading a heating element into a glass melting furnace for vitrifying radioactive waste, and may include a main frame (100), a universal joint (110) located at one end of the main frame (100), at least one heating element fastening part (120) that is connected to and rotates with the universal joint (110), and a gripper (130) located at an end of the heating element fastening part (120) and that grips the heating element (5).

[0038] The main frame (100) forms the main body of the glass melting furnace heating element loading device (10) and may be in the form of a bar extending from one end to the other.

[0039] A universal joint (110) is positioned at one end of the main frame (100). A heating member (120) is connected to the universal joint (110). The heating member (120) can rotate at one end of the main frame (100) by the universal joint (110). In addition, the universal joint (110) can be connected while rotating at one end of the main frame (100). Accordingly, the main frame (100) can also rotate by the universal joint (110).

[0040] The heating body attachment part (120) can be positioned at one end of the main frame (100) by a universal joint (110).

[0041] The heating body fastening member (120) may be a bar type in the shape of a rod. A plurality of heating body fastening members (120) may be connected to the universal joint (110). Since the heating body fastening members (120) are configured in multiple pieces, the load of the heating element (5) held at the end of the heating body fastening members (120) can be distributed to each of the multiple heating body fastening members (120).

[0042] One end of the heating body fastening member (120) is connected to the universal joint (110) and can be rotated and joined at the universal joint (110). For example, the heating body fastening member (120) can be rotated at an angle of less than 90° by the universal joint (110). The heating body fastening member (120) can be rotated away from the main frame (100) or rotated closer to the main frame (100).

[0043] The gripper (130) is located at the end of the heating body fastening portion (120) and can hold the heating body (5). The gripper (130) can be located at the end of each heating body fastening portion (120). If the number of heating body fastening portions (120) is plural, the gripper (130) can also be provided plural times. In FIG. 1, for example, four heating body fastening portions (120) are illustrated, and the gripper (130) can be provided at the end of each heating body fastening portion (120).

[0044] Referring to FIG. 2, the gripper (130) may include a support portion (210) and a grip portion (220) connected to the support portion (210).

[0045] The support member (210) is coupled to the heating body fastening member (120) and may include a hole (not shown) through which an adjustment wire (150) that can adjust the first finger member (221) and the second finger member (222) of the grip member (220) passes. The support member (210) may support the grip member (220) so that the first and second fingers (221, 222) of the grip member (220) can grip the heating body (5).

[0046] The gripping portion (220) of the gripper (130) may include a first finger portion (221), a second finger portion (222) coupled with the first finger portion (221), a first joint (231) coupled with the first finger portion (221) and the second finger portion (222), and a second joint (232) coupled with the first finger portion (221) and the second finger portion (222) to the support portion (210).

[0047] The first finger portion (221) and the second finger portion (222) are connected by the first joint (231) and the second joint (232) and can move to grip the heating element (5). That is, when the first finger portion (221) and the second finger portion (222) of the grip portion (220) grip the heating element (5), the first finger portion (221) and the second finger portion (222) can move so that the gap between the first finger portion (221) and the second finger portion (222) becomes closer.

[0048] On the other hand, when the first finger part (221) and the second finger part (222) of the grip part (220) release the grip of the heating element (5) by charging the heating element (5) into the glass melting furnace, the first finger part (221) and the second finger part (222) can move so that the gap between the first finger part (221) and the second finger part (222) increases.

[0049] As described above, in order to control the movement of the first finger portion (221) and the second finger portion (222), a control wire (150) may be included. That is, the glass melting furnace heating element loading device (10) according to the embodiment of the present invention may include a control wire (150) that is connected to the first joint (231) and controls the movement of the first finger portion (221) and the second finger portion (222) so that the first finger portion (221) and the second finger portion (222) grip the heating element (5) or release the grip of the heating element (5).

[0050] The control wire (150) can control the movement of the first finger portion (221) and the second finger portion (222) by applying tension to the first joint (231) or not applying tension.

[0051] The control wire (150) can be connected to the first joint (231) through the hole of the support member (210). In addition, the control wire (150) can pass through the interior of the heating body fastening member (120) by means of a control wire through hole (not shown) formed inside the heating body fastening member (120). That is, the control wire (150) can be positioned by penetrating the support member (210) of the gripper (130) and the interior of the heating body fastening member (120). Meanwhile, the control wire (150) can pass through a part of the heating body fastening member (120) and then be pulled out from the middle part of the heating body fastening member (120). The pulled out control wire (150) can be connected to the control member (180) described later.

[0052] The control unit (180) controls the release and fixation of the control wire (150) and can be located at the other end of the main frame (100). For example, when the control wire (150) is fixed by the operation of the control unit (180), tension is applied to the first finger unit (221) and the second finger unit (222), and the first finger unit (221) and the second finger unit (222) can grip the heating element (5). In addition, when the control wire (150) is released by the operation of the control unit (180), tension is not applied to the first finger unit (221) and the second finger unit (222), and the first finger unit (221) and the second finger unit (222) can release the grip of the heating element (5).

[0053] Meanwhile, the glass melting furnace heating element loading device (10) according to the embodiment of the present invention may include a reference part (170) that is positioned to slide on the main frame (100) and controls the behavior of the heating element fastening part (120).

[0054] Referring to FIGS. 1 and 3, when the reference part (170) slides in one direction of the main frame (100), the heating body fastening part (120) can be rotated away from the main frame (100). The heating body fastening part (120) can be rotated to form a 90° angle with the main frame (100).

[0055] Meanwhile, when the reference part (170) slides in a direction opposite to one end of the main frame (100), the heating body fastening part (120) can be rotated to approach the main frame (100). By rotating the heating body fastening part (120) to approach the main frame (100), the glass melting furnace heating body loading device (10) can be easily withdrawn to the outside of the glass melting furnace.

[0056] Referring to FIG. 4, the method of loading a heating element (5) into a glass melting furnace using a heating element loading device (10) according to an embodiment of the present invention is described.

[0057] In the early days of vitrification, workers loaded the heating element directly, without any separate equipment. However, in an emergency, the presence of radioactive waste makes it difficult for workers to work in close proximity. In the event of an emergency shutdown of the vitrification furnace, the glass inside the molten glass is completely removed to restart the vitrification process. This poses a risk of radiation exposure or accidents to workers during glass removal.

[0058] During the vitrification process, a heating element (Ti-ring) is inserted into the furnace to generate heat and oxidize the molten glass. During the radioactive waste treatment process, if an emergency shutdown occurs, the internal molten glass cools, requiring the addition of additional heating elements to restart the furnace.

[0059] To this end, the trap door (2) in the upper chamber of the glass melting furnace (1) is opened to secure space for additional charging of the heating element (5).

[0060] Thereafter, a worker (or robot) loads a circular heating element (5) into the glass melting furnace using a heating element loading device (10). More specifically, the heating element (5) at the end of the heating element attachment part (120) is gripped by a gripper (130). To this end, tension is applied to the first finger (221) and the second finger (222) of the gripper (130) using a control wire (150), and the control wire (150) is fixed to the control part (180).

[0061] The heating element loading device (10) of the glass melting furnace, which has the heating element (5) gripped, is introduced into the glass melting furnace (1) through the trap door (2). Thereafter, the tension applied to the gripper (130) is released through the control wire (150), and the heating element (5) gripped by the first and second fingers (221, 222) is loaded onto the glass melt. Thereafter, the reference part (170) on the main frame (100) is slid in the other direction, and the heating element fastening part (120) is rotated to approach the main frame (100) (see FIG. 3), and then the heating element loading device (10) of the glass melting furnace is withdrawn from the glass melting furnace (1).

[0062] Using the glass melting furnace heating element loading device (10) according to the embodiment of the present invention, the heating element (5) is loaded into the glass melting furnace (1) through the above process.

[0063] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical concept or essential features thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

Claims

1. In a device for loading a heating element into a glass melting furnace for vitrifying radioactive waste, mainframe; A universal joint located at one end of the above main frame; At least one heating member that is connected to and rotates with the universal joint; and A glass melting furnace heating element loading device including a gripper located at the end of the heating element attachment part and holding the heating element.

2. In paragraph 1, The above gripper is a glass melting furnace heating element loading device including a support portion and a grip portion connected to the support portion.

3. In paragraph 2, A glass melting furnace heating element loading device including a first finger portion, a second finger portion coupled to the first finger portion, a first joint coupling the first finger portion and the second finger portion, and a second joint coupling the first finger portion and the second finger portion to the support portion, respectively.

4. In paragraph 3, A glass melting furnace heating element loading device further comprising a control wire connected to the first joint and controlling the movement of the first finger portion and the second finger portion so that the first finger portion and the second finger portion grip the heating element or release the grip of the heating element.

5. In paragraph 4, A glass melting furnace heating element loading device further comprising a control unit positioned at the other end of the main frame and controlling the release and fixation of the above control wire.

6. In paragraph 1, A glass melting furnace heating element loading device further comprising a reference part that is positioned to slide on the main frame and controls the behavior of the heating element fastening part.

7. In paragraph 6, When the above reference part slides in the direction of the above main frame, A glass melting furnace heating element loading device in which the above heating element attachment part rotates away from the main frame.

8. In paragraph 6, When the above reference part slides in the opposite direction to the above end of the main frame, A glass melting furnace heating element loading device in which the above heating element attachment part rotates so as to be close to the above main frame.

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