JP2001337195A - Molten glass falling velocity control mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate operation control of a glass melting furnace. SOLUTION: This mechanism is equipped with a falling velocity computing unit 14 for obtaining the falling velocity of molten glass G falling from a falling nozzle 8 to a solidified body vessel 11 as a process value, a falling velocity setter 19 for setting the target value of the falling velocity of the molten glass G, a velocity difference computing unit 20 for obtaining deviation of the process value relative to the target value of the falling velocity, based on signals from the falling velocity computing unit 14 and the falling velocity setter 19, an input power computing unit 21 for obtaining input power energy to be supplied to an induction heating coil 9, based on a signal 20s from the velocity difference computing unit 20, and a heating device 16 for supplying power E1 to the induction heating coil 9, based on a signal 21s from the input power computing unit 21. In the mechanism, the input power energy into the induction heating coil 9 is increased or decreased, by using the deviation of the process value relative to the target value of the falling velocity as a control parameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten glass falling speed control mechanism.

[0002]

2. Description of the Related Art Radioactive liquid waste generated from nuclear facilities is:
After being vitrified by waste liquid treatment equipment, it is stored in a waste storage facility.

FIG. 2 shows an example of a glass melting furnace which constitutes a waste liquid treatment facility. This glass melting furnace has a melting space 1 whose horizontal opening cross section gradually decreases downward from an intermediate portion in the vertical direction. And a melting furnace main body 2 formed of a refractory material.

In the upper part of the melting furnace body 2, a raw material supply pipe 3,
The waste liquid supply pipe 4 and the exhaust pipe 5 are connected so as to communicate with the melting space 1.

[0005] In the melting furnace body 2, a pair of main electrodes 6 facing each other at an intermediate portion in the vertical direction of the melting space 1 and a bottom electrode 7 located near the bottom of the melting space 1 are stored in the melting space 1. It is provided so as to be immersed in the molten glass G.

[0006] At the lower part of the melting furnace body 2, a downflow nozzle 8 communicating with the melting space 1, an induction heating coil 9 surrounding the downflow nozzle 8, and an air injection pipe capable of blowing cooling air to the downflow nozzle 8. 10 are provided.

Below the melting furnace main body 2, there is provided a transport trolley 13 having a load detector 12 on which a solidified metal container 11 is placed and movable directly below the falling nozzle 8. I have.

Further, a load detector 12 is provided in the glass melting furnace.
Velocity calculator 1 for differentiating instantaneous gravity with time based on the load detection signal 12s output from the controller to obtain the velocity of the molten glass G flowing out of the flow-down nozzle 8 into the solidified container 11.
4, a molten glass current meter 15 for displaying the flowing speed of the molten glass G based on the flowing speed signal 14s output from the flowing speed calculator 14, and a first power supply E1 to the induction heating coil 9. Heating device 16 and both main electrodes 6, 6
Alternatively, a second heating device 17 for supplying electric power E2 to one of the main electrode 6 and the bottom electrode 7 is provided.

In the glass melting furnace shown in FIG. 2, the raw material glass fed from the raw material supply pipe 3 to the melting space 1 is melted by a heater (not shown) attached to the main body 2 of the melting furnace. Electric power E2 is supplied to 6, 6, or one of the main electrode 6 and the bottom electrode 7, and the molten glass G in the molten space 1 is kept warm so as not to be solidified by Joule heat.

At this time, the glass is solidified in the downflow nozzle 8 and the outflow of the molten glass G from the molten space 1 to the outside is suppressed.

In this state, the raw material supply pipe 3 and the melting space 1
When the glass raw material is supplied to the molten glass G, the raw glass melts into the molten glass G. When the waste liquid is supplied from the waste liquid supply pipe 4 to the melting space 1, the waste liquid is mixed into the molten glass G.

In the vitrification treatment of the waste liquid, the solidified container 11 is mounted on a carrier 13 and the solidified container 11
The transport carriage 13 is moved so that is located immediately below the downflow nozzle 8.

Further, by supplying electric power E1 to the induction heating coil 9, the downstream nozzle 8 is heated, and the downstream nozzle 8 is heated.
The glass solidified therein is melted, and the molten glass G mixed with the waste liquid flows out from the downflow nozzle 8 to the solidified container 11.

At this time, based on the load detection signal 12s from the load detector 12, the solidified container 11
The falling speed of the molten glass G flowing down is calculated by the falling speed calculator 14, and the falling speed of the molten glass G according to the falling speed signal 14s from the falling speed calculator 14 is displayed on the molten glass current meter 15. You.

When the supply of the electric power E1 to the induction heating coil 9 is interrupted, the temperature of the falling nozzle 8 gradually decreases, the glass solidifies in the falling nozzle 8, and the molten glass G from the melting space 1 to the outside is melted. The outflow is suppressed, and the molten glass G filled in the solidified container 11 is solidified by natural air cooling,
A vitrified body is formed.

At the time of filling the molten glass into the solidified container 11, the operator operates the display of the molten glass anemometer 15 and the temperature of the molten glass G while keeping the input power to one of the main electrode 6 and the bottom electrode 7 constant. While confirming the above, the amount of electric power supplied to the induction heating coil 9 is increased or decreased to control the flow rate of the molten glass G.

[0017]

However, when the molten glass G is caused to flow down from the downflow nozzle 8 to the solidified container 11, it is determined by the operator whether or not the amount of electric power supplied to the induction heating coil 9 should be increased or decreased. Also, since the response delay occurs after the amount of electric power supplied to the induction heating coil 9 is increased or decreased and before the flow rate of the molten glass G changes, the operation of the glass melting furnace requires skill. .

The present invention has been made in view of the above circumstances, and has as its object to facilitate operation of a glass melting furnace.

[0019]

In order to achieve the above object, a molten glass falling speed control mechanism according to the present invention comprises a load detecting device for detecting the weight of molten glass flowing from a melting furnace body into a solidified container via a falling nozzle. A flow rate calculating device for calculating the flow rate of the molten glass flowing down from the flow down nozzle to the solidified body container as a process value based on a signal from the load detector, and a flow down rate for setting a target value of the flow rate of the molten glass. A setting device, a speed difference calculator for calculating a deviation of a process value from a target value of the falling speed based on signals from the falling speed calculator and the falling speed setter, and a falling nozzle heating device based on a signal from the speed difference calculator. An input power calculator for calculating the input power to be supplied to the coil, and a heating device for supplying power to the downstream nozzle heating coil based on a signal from the input power calculator. To have.

In the molten glass falling speed control mechanism of the present invention, a signal is output from the input power calculator to the heating device based on the deviation of the process value from the target value of the flowing speed, and the input power to the falling nozzle heating coil is output. Adjust the volume.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an embodiment of a molten glass falling speed control mechanism according to the present invention. In FIG. 1, the same reference numerals as in FIG. 2 denote the same parts.

The molten glass falling speed control mechanism includes the load detector 12, the falling speed calculator 14, the molten glass flow meter 15, the first heating device 16, and the second heating device 1.
7, a falling speed setting device 19, a speed difference calculator 20,
An input power calculator 21 is provided.

The falling speed setting device 19 is adapted to set a target falling speed signal 1 according to a preset target falling speed of the molten glass G.
It is configured to output 9 s.

The speed difference calculator 20 is provided with a falling speed calculator 14.
Of the process value with respect to the target value of the flowing speed of the molten glass G at the present time based on the falling speed signal 14s from the controller and the target falling speed signal 19s from the falling speed setting device 19, and a speed difference signal corresponding to the difference. It has the function of outputting 20s.

The input power calculator 21 includes a speed difference calculator 20.
Based on the speed difference signal 20 s from the controller, an input power amount to be supplied to the induction heating coil 9 is obtained, and an input power amount signal 21 s is output to the first heating device 16.

The operation of the molten glass falling speed control mechanism shown in FIG. 1 will be described below.

A constant electric power E is generated by the second heating device 17.
When electric power E1 is supplied from the first heating device 16 to the induction heating coil 9 to heat the downflow nozzle 8 while supplying 2 to the main electrode 6 and the bottom electrode 7, the molten glass G in the melting furnace body 2 is solidified. At the beginning of flowing down into the body container 11, the flowing speed calculator 14 calculates the flowing speed of the molten glass G based on the load detection signal 12s from the load detector 12, and outputs a flowing speed signal 14s.

The speed difference calculator 20 is provided with a falling speed signal 14 s from the falling speed calculator 14 and a falling speed setting device 19.
The deviation of the process value from the target value of the flowing speed of the molten glass G at the current time is obtained based on the target flowing speed signal 19s from the target.

If there is a deviation between the target value and the process value, a speed difference signal 20
s is output, and the input power calculator 21 outputs the speed difference signal 20
s based on the input power amount signal to be supplied to the induction heating coil 9, and the input power amount signal 21 to the first heating device 16.
Output s.

When the viscosity of the molten glass G is high and the process value of the falling speed is lower than the target value, the molten glass G is supplied from the first heating device 16 to the induction heating coil 9 in accordance with the supplied electric energy signal 21s. The heating state of the flow-down nozzle 8 is adjusted so that the electric power E1 increases and the viscosity of the molten glass G decreases, and the flow-down speed of the molten glass G is improved.

When the viscosity of the molten glass G is relatively low and the process value of the falling speed is higher than the target value, the molten glass G is supplied from the first heating device 16 to the induction heating coil 9 in accordance with the supplied electric energy signal 21s. The heating state of the flow-down nozzle 8 is adjusted so that the electric power E1 decreases and the viscosity of the molten glass G increases, so that the flow-down speed of the molten glass G is suppressed.

As described above, in the molten glass falling speed control mechanism shown in FIG. 1, the deviation of the process value from the target value of the falling speed of the molten glass G is used as a control parameter.
Since the amount of electric power supplied to the induction heating coil 9 is increased or decreased, it is possible to cause the molten glass G to flow down at a flow rate according to the target value.

It should be noted that the molten glass falling speed control mechanism of the present invention is not limited to the above-described embodiment, but may be modified without departing from the scope of the present invention.

[0035]

As described above, in the molten glass falling speed control mechanism of the present invention, a signal is output from the input power calculator to the heating device based on the deviation of the process value from the target value of the falling speed of the molten glass. Since the amount of power supplied to the downflow nozzle heating coil is adjusted, the operation of the glass melting furnace is facilitated and the burden on the operator is reduced.
Excellent effects can be achieved.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a glass melting furnace provided with an example of an embodiment of a molten glass falling speed control mechanism of the present invention.

FIG. 2 is a conceptual diagram illustrating an example of a glass melting furnace.

[Explanation of symbols]

 2 Melting furnace body 8 Downflow nozzle 9 Induction heating coil (downflow nozzle heating coil) 11 Solidified container 12 Load detector 12s Load detection signal 14 Downflow speed calculator 14s Downflow speed signal 16 First heating device 19 Downflow speed setting device 19s Target falling speed signal 20 Speed difference calculator 20s Speed difference signal 21 Input power calculator 21s Input power signal E1 Power G Molten glass

Claims (1)

[Claims] 1. A load detector for detecting the weight of molten glass flowing from a melting furnace body into a solidified container via a flow-down nozzle, and a melt flowing down from the flow-down nozzle to the solidified container based on a signal from the load detector. A falling speed calculator for calculating the falling speed of the glass as a process value, a falling speed setter for setting a target value for the falling speed of the molten glass, and a target for the falling speed based on signals from the falling speed calculator and the falling speed setter. A speed difference calculator for determining the deviation of the process value from the value,
An input power calculator for calculating an input power to be supplied to the downstream nozzle heating coil based on a signal from the speed difference calculator; and supplying power to the downstream nozzle heating coil based on a signal from the input power calculator. A molten glass flow-down speed control mechanism comprising a heating device.