JP3861327B2 - Vitrification equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vitrification apparatus for vitrifying a high level radioactive liquid waste.
[0002]
[Prior art]
Conventionally, high-level radioactive liquid waste discharged from radioactive waste reprocessing factories is inconvenient to handle in the liquid state, so it is fused with glass raw materials in a glass melting furnace and then made into a solidified stainless steel called canister. By being poured into a container and solidified, it is made into a stable vitrified body, and then stored for a long time in a predetermined place such as a vitrified body storage facility.
[0003]
And the vitrification body of a high level radioactive waste liquid is made by the vitrification processing apparatus as shown in FIG. 2, for example.
[0004]
That is, as shown in the drawing, first, the high-level radioactive liquid waste 1 is put into the glass melting furnace 3 together with the glass raw material 2 and melted by Joule heating using the main electrode 4 and the furnace bottom auxiliary electrode 5 to be molten glass. After reaching 6, it reaches the falling nozzle 7 provided at the lower part of the glass melting furnace 3. At the lower part of the glass melting furnace 3, there is provided a coupler 9 for connecting the falling nozzle 7 and a glass solidified container 8 called a canister, and the molten glass 6 reaching the flowing nozzle 7 is composed of a high-frequency heating coil. After flowing down through a flow nozzle 7 heated at high frequency by 10, passing through a flow path 11 in the coupler 9 and being injected into the glass solidified body container 8 disposed below the flow path 11, the support carriage 12 performs a predetermined process. Then, it will be processed as a vitrified body.
[0005]
Further, as shown in the figure, a glass sampling device 13 for examining the composition of the molten glass 6 is provided between the coupler 9 and the vitrified container 8.
[0006]
[Problems to be solved by the invention]
However, in the above-mentioned vitrification apparatus, since the molten glass 6 flowing down from the flow nozzle 7 is viscous, the temperature of the molten glass 6 is low and the viscosity of the molten glass 6 is high. There are cases where the molten glass 6 does not flow straight down due to a cause such as the glass clogged in the nozzle 7 not falling off.
[0007]
Then, the molten glass 6 flows down obliquely and is caught on the coupler 9 or the like and deposited on the coupler 9.
[0008]
In view of the above circumstances, an object of the present invention is to provide a vitrified body treatment apparatus capable of automatically stopping the flow of molten glass when a flow abnormality occurs.
[0009]
[Means for Solving the Problems]
The present invention has a glass melting furnace for generating molten glass, a flowing nozzle for flowing down the molten glass in the glass melting furnace, and a control unit for controlling power supply to a high-frequency heating coil provided on the outer periphery of the flowing nozzle. In a vitrification apparatus in which molten glass in which a high-level radioactive waste liquid is melted is applied to a high-frequency heating coil to flow down from a flow-down nozzle and is poured into a glass-solidified container disposed below the molten glass. , provided with a load detector for detecting a load of the vitrified container, when the falling abnormality of the molten glass occurs, cut off the power supply signal under a load detection signal from the load detector, the melt from the falling nozzle The present invention relates to a vitrification apparatus characterized in that an interlock system for stopping the flow of glass is provided in the control unit .
[0010]
The interlock system calculates the molten glass flow velocity per unit time based on the load detection signal from the load detector, the reference flow velocity function set in the function generator, and the flow velocity calculated by the calculator A comparison calculator that generates an interlock signal when the falling velocity signal is out of a predetermined range based on the reference falling velocity function may be provided.
[0011]
According to the above means, the following operation can be obtained.
[0012]
The molten glass in which the high-level radioactive liquid waste has been melted flows down from a flow nozzle at the bottom of the glass melting furnace and is poured into a glass solidified container disposed below the molten glass.
[0013]
When an abnormal flow of the molten glass into the vitrified container occurs, an interlock system provided in the control unit is activated in response to a signal from the load detector, and the molten glass flows from the flow nozzle. Is automatically stopped.
[0014]
More specifically, a load detector that detects the load of the vitrified container sends a load detection signal indicating the load of the vitrified container to the computing unit provided in the interlock system, and the computing unit detects the load. The flow rate of molten glass per unit time is obtained based on the load detection signal from the vessel.
[0015]
The downstream velocity signal obtained by the computing unit is sent to the comparison computing unit, and the comparison computing unit compares the reference downstream velocity function set in the function generator with the downstream velocity signal obtained by the computing unit.
[0016]
Here, when the flow velocity signal is within a predetermined range based on the reference flow velocity function, the comparison calculator does not emit any signal, so the flow of molten glass from the flow nozzle is continued. .
[0017]
When the flow velocity signal deviates from a predetermined range based on the reference flow velocity function, it means that some flow abnormality has occurred, and therefore the comparison arithmetic unit generates an interlock signal.
[0018]
By this interlock signal, the interlock system is activated, and the flow of molten glass from the flow nozzle is automatically stopped.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Next, a preferred embodiment for carrying out the present invention will be described.
[0020]
FIG. 1 shows an embodiment of a vitrified body treatment apparatus according to the present invention.
[0021]
As shown in the drawing, the vitrified body processing apparatus includes a glass melting furnace 15 that generates molten glass 14, a flowing-down nozzle 16 that flows down the molten glass 14 in the glass melting furnace 15, a flowing-down nozzle 16, and a glass-solidified body container 17. , A glass sampling device 19 provided between the coupler 18 and the vitrified body container 17, and a control unit 21 that controls power supply to the high-frequency heating coil 20 provided on the outer periphery of the falling nozzle 16. And is composed mainly of.
[0022]
First, the glass melting furnace 15 includes a funnel-shaped furnace body 22 provided with a main electrode 23 and a furnace bottom auxiliary electrode 24, and a heat insulating layer 25 provided around the main electrode 23 and a furnace tube 22. The high-level radioactive liquid waste 27 and the glass raw material 28 charged from 26 are melted by Joule heating by the main electrode 23 and the furnace bottom auxiliary electrode 24 to form the molten glass 14. The exhaust gas in the furnace body 22 is discharged to the outside through an exhaust pipe 29 connected to the top of the furnace body 22.
[0023]
The flow-down nozzle 16 connected to the bottom of the furnace body 22 communicates with the interior of the furnace body 22, and the high-frequency heating coil 20 is wound around the pipe body 30 extending vertically downward therefrom. The pipe body 30 is heated by applying a high-frequency current to the high-frequency heating coil 20 from a control unit 21 to be described later, and the glass solidified in the pipe body 30 is melted and extracted, and the molten glass inside the furnace body 22 is extracted. 14 is made to flow down.
[0024]
Further, as described above, the coupler 18 couples the flow-down nozzle 16 and the stainless glass vitrified body container 17 disposed below, and the flow-down state is applied to the guide tube 32 forming the flow-down path 31. A viewing window 33 to be confirmed and a heating means 34 for preventing the flow path 31 from being blocked are provided.
[0025]
Furthermore, the vitrified container 17 disposed below the coupler 18 is supported and erected in a support carriage 36 that runs on the rail 35, and is sequentially fed to the lower part of the coupler 18 by the support carriage 36. It has become so.
[0026]
Next, as shown in FIG. 1, the control unit 21 is mainly composed of a down nozzle heating control unit 37 and a power source control unit 38, and power control is performed by a down switch 39 provided in the down nozzle heating control unit 37. The thyristor 40 of the unit 38 is controlled to supply power from the power supply unit 41.
[0027]
An interlock system 44 having a relay switch 43 for connecting / disconnecting a power feeding signal is provided on a signal line 42 connecting the downstream switch 39 in the downstream nozzle heating controller 37 and the thyristor 40 of the power controller 38. The power supply signal from the down switch 39 to the power supply control unit 38 can be cut off.
[0028]
The support carriage 36 is provided with a flow-down abnormality detector such as a load detector 45 for detecting the load of the vitrified container 17. The flow-down nozzle heating control unit 37 includes a flow-down abnormality detector. When the switch 39 is turned on, a calculator 47 that starts to determine the flow velocity of the molten glass 14 per unit time based on the load detection signal 46 from the load detector 45, and a reference flow velocity function set in the function generator 48 49 and the flow velocity signal 50 obtained by the computing unit 47 are compared, and when the flow velocity signal 50 is out of a predetermined range based on the reference flow velocity function 49, a warning signal is sent to the flow abnormality alarm 51. 52 and a comparator 54 that sends an interlock signal 53 to the relay switch 43.
[0029]
Next, the operation of the embodiment of the present invention will be described.
[0030]
First, the support carriage 36 that supports the vitrified glass container 17 is moved along the rail 35, and the vitrified glass container 17 is disposed below the flow-down nozzle 16 of the glass melting furnace 15. The container 17 is connected, the flow down switch 39 of the control unit 21 is turned on, a power supply signal is sent to the thyristor 40 of the power supply control unit 38 via the signal line 42, and the high frequency of the flow down nozzle 16 from the power supply unit 41 of the power supply control unit 38. A high frequency current is applied to the heating coil 20.
[0031]
Then, the falling nozzle 16 is heated at a high frequency by the high-frequency heating coil 20, and the glass that has closed the falling nozzle 16 is melted and falls off, and the flowing of the molten glass 14 in the glass melting furnace 15 from the falling nozzle 16 is started. The molten glass 14 is poured into the glass solidified body container 17 while flowing down the axial center portion of the flow path 31 of the coupler 18 and the glass sampling device 19 while flowing down in a filament shape.
[0032]
The support carriage 36 that supports the vitrified container 17 is provided with a load detector 45 that detects the load of the vitrified container 17. The load detector 45 is provided in the falling nozzle heating control unit 37. A load detection signal 46 indicating the load of the vitrified container 17 is sent to the computing unit 47. At the same time when the flow down switch 39 is turned on, the computing unit 47 uses the load detection signal 46 from the load detector 45 as a basis. Then, the flow rate of the molten glass 14 per unit time is determined.
[0033]
The downstream velocity signal 50 obtained by the computing unit 47 is sent to the comparison computing unit 54, which compares the reference downstream velocity function 49 set in the function generator 48 and the downstream velocity signal 50 obtained by the computing unit 47. And compare.
[0034]
Here, when the flow velocity signal 50 is within a predetermined range with the reference flow velocity function 49 as a reference, the comparison calculator 54 does not generate any signal, so the flow from the flow nozzle 16 of the molten glass 14. The flow continues.
[0035]
If the flow velocity signal 50 deviates from a predetermined range based on the reference flow velocity function 49, it means that some flow abnormality has occurred, so the comparison calculator 54 sends a warning signal to the flow abnormality alarm 51. 52 is sent to issue an alarm, and an interlock signal 53 is sent to the relay switch 43.
[0036]
Since the relay switch 43 is turned off by the interlock signal 53, the signal line 42 connecting the flow down switch 39 of the control unit 21 and the thyristor 40 of the power supply control unit 38 is cut off. The power supply signal is not transmitted to the 38 side. Therefore, the flow of the molten glass 14 from the flow nozzle 16 is automatically stopped, and the inconvenience that the molten glass 14 is deposited on the coupler 18 and the flow path 31 is blocked is prevented.
[0037]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain an excellent effect that the flow of molten glass can be automatically stopped when a flow abnormality occurs.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.
FIG. 2 is an overall view showing an example of a conventional vitrification apparatus.
[Explanation of symbols]
14 Molten glass 15 Glass melting furnace 16 Flowing nozzle 17 Vitrified container 21 Control unit 27 High-level radioactive liquid waste 44 Interlock system 45 Load detector (flowing abnormality detector)
46 Load detection signal 47 Calculator 48 Function generator 49 Reference flow velocity function 50 Flow velocity signal 53 Interlock signal 54 Comparison operator

Claims (1)

A glass melting furnace for generating molten glass, a falling nozzle at the bottom of the glass melting furnace for flowing down the molten glass in the glass melting furnace, and a control unit for controlling power supply to a high-frequency heating coil provided on the outer periphery of the flowing nozzle Vitrification by applying a high-frequency current to the high-frequency heating coil so that molten glass in which high-level radioactive waste liquid is dissolved flows down from the flow-down nozzle and is poured into a glass-solidified container disposed below it. In the processing apparatus, a load detector for detecting the load of the vitrified container is provided, and when an abnormal flow of the molten glass occurs, the load detection signal is received from the load detector and the power supply signal is cut off. an interlock system to stop stream of molten glass from provided in the control unit, the interlock system, the load detector The calculator that calculates the molten glass flow velocity per unit time based on the load detection signal and the reference flow velocity function set in the function generator and the flow velocity signal obtained by the calculator are used to compare the flow velocity signal. A vitrification processing apparatus comprising: a comparator for generating an interlock signal when a deviation from a predetermined range based on a reference flow velocity function is detected.

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