JPH0712996A - Glass melting furnace - Google Patents

Abstract

PURPOSE:To prevent the generation of cold top and improve the operating efficiency by supplying heat from an assisting melting tank to the vicinity of the liquid level and a part of low temperatures where the glass material is supplied. CONSTITUTION:A main electrode 3, an assisting electrode 3B and a bottom electrode 5 are arranged in a main melting tank 11. A current is fed to each electrode 3, 3B, 5 to generate a resistance heat. At this time, the resistance heat is also transmitted inside an auxiliary melting tank 13 via a diaphragm wall 12. Accordingly, a liquid surface of the molten substance is formed in the melting tanks 11, 13 via a communication port 14. When a glass material is supplied into the main melting tank 11 through an upper opening 7 in this state, a part of low temperatures is generated in the vicinity of the liquid surface of the molten substance. In contrast, the molten substance of high temperatures remains in the auxiliary melting tank 13, the heat of which is transmitted via the communication port 14. As a result, the part at low temperatures is turned into the melting state, whereby the cold top is solved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass melting furnace,
In particular, the effective use of heat reduces the generation of cold tops.

[0002]

2. Description of the Related Art In a glass melting furnace, a material to be heated is charged between electrodes facing each other, and the fact that the material to be heated or the material to be melted has electrical conductivity is utilized. An electric current is passed to generate resistance heat and melt an object to be heated. Examples of the object to be heated include glass used for solidifying high-level radioactive waste (waste liquid).

4 and 5 are shown in Japanese Unexamined Patent Publication No. 4-161896.
1 shows an example of a conventional structure of a melting furnace disclosed in Japanese Patent Laid-Open No. 4-161897. In each drawing, reference numeral 1 is a main melting tank, 2 is a side wall, 3 is an electrode, 4 is a bottom wall, 5 is a bottom electrode, 6 is a ceiling wall, 7 is a raw material supply port, 8 is a discharge port,
9 is a downflow nozzle, 10 is an inclined inner wall surface, and X is a melt.

In such a melting furnace, an electric current is caused to flow through the molten material X which is a conductor interposed between the pair of electrodes 3 or between the electrode 3 and the bottom electrode 5 to generate a high temperature state by resistance heating. I try to keep it.

[0005]

However, since the glass raw material is intensively dropped in the vicinity of just below the raw material supply port 7, the cold top near the surface of the melt X or the cold top which remains unmelted. Occurs, the current distribution becomes non-uniform, and the operating efficiency of the glass melting furnace may be reduced.

The present invention effectively solves such a problem. That is, the purpose is to improve the operating efficiency by adding heat supply from the upper side and the side to the low temperature portion and the vicinity of the liquid level where the glass raw material is dropped.

[0007]

[Means for Solving the Problems] Several means for solving the problems are proposed. A first means is a main electrode that causes a melt contained in the main melting tank to generate heat by applying electricity, an auxiliary melting tank that is arranged on a side portion of the main melting tank and is isolated by a partition wall, and the auxiliary melting tank The glass melting furnace is configured to have a plurality of communication ports that are arranged on the isolation walls at the bottom position and the position near the liquid level of the melt and that connect the insides of both tanks. In addition to the first means, the second means employs a configuration in which an upper opening connecting the internal spaces of both tanks is opened in the isolation wall located above the liquid level of the melt. The third means employs a configuration in which, in addition to the first means and the second means, a side electrode is disposed in the auxiliary melting tank for heating the melt by resistance heating. The fourth means adopts a configuration in which, in addition to the first means, the second means and the third means, a liquid level meter for measuring the liquid level of the melt is arranged in the auxiliary melting tank. There is.

[0008]

In the first means, a current is caused to flow between the main electrodes to generate resistance heat in the melt to raise the temperature,
At this time, heat is also transferred to the inside of the auxiliary melting tank, and a liquid level of the melt is formed in both tanks. When a glass material is introduced into the main melting tank while passing an electric current between the main electrodes, a low temperature part is generated near the liquid surface of the melt, but the auxiliary melting tank part contains the melt in a high temperature state. Left untouched. From the melt inside the auxiliary melting tank, heat is transferred from the side to the low temperature part through the communication port of the isolation wall, and the low temperature part becomes in a molten state, leading to the cold top in the extinguished state. Get burned. In the second means, in addition to the action of the first means, the heat of the melt inside the auxiliary melting tank is
Heat is transferred from above to the low temperature portion of the main melting tank via the upper opening, and the low temperature portion is also heated from the surface. In the third means, in addition to the functions of the first means and the second means, the melted material in the auxiliary melting tank is resistance-heated by the energization of the side electrodes, thereby melting the inside of the auxiliary melting tank. By raising the temperature of the material, the cold part of the main melting tank is heated. In the fourth means, in addition to the actions of the first means, the second means, and the third means, by measuring the liquid level of the melt in the auxiliary melting tank, the low temperature part is added to the main melting tank. The liquid level in the main melting tank is measured even in the case where the water is formed.

[0009]

EXAMPLES A first example of the glass melting furnace according to the present invention will be described below with reference to FIGS. 1 and 2. In FIGS. 1 and 2, reference numeral 3B is an auxiliary electrode, 11 is a main melting tank, 12 is an isolation wall, 13 is an auxiliary melting tank, 14 is a communication port, 15 and 16
Is an internal space, 17 is an upper opening, 18 is a side electrode, and 19 is a liquid level meter.

In the main melting tank 11, the main electrode 3 is arranged on the side wall 2 and the main electrode 3 is formed on the inclined inner wall surface 10.
The auxiliary electrode 3B having a 90 degree relationship with the facing direction, the bottom electrode 4 on the bottom wall 4, the raw material supply port 7 on the ceiling wall 6, and the bottom wall 4
A discharge port 8 and a flow-down nozzle 9 are provided in each.

The partition wall 12 divides the main melting tank 11 and the auxiliary melting tank 13 into each other, and a plurality of communication ports 14 are opened so as to connect the main melting tank 11 and the auxiliary melting tank 13.

The auxiliary melting tank 13 is provided side by side with the main melting tank 11 in an isolated state by an isolation wall 12, and the auxiliary electrode 3B is provided on the side wall 2 at the time of starting.
A side electrode 18 for energizing (or the main electrode 3) and a liquid level meter 19 for measuring the liquid level of the melt X are arranged.

The communication port 14 is located at a bottom position of the auxiliary melting tank 13, a position near the liquid level (liquid level) RL of the melt X, a position near upper portions of the main melting tank 11 and the auxiliary melting tank 13, and an intermediate position. It is arranged in each position.

On the other hand, FIG. 3 shows a second embodiment of the glass melting furnace according to the present invention, in which both internal spaces 15 are provided in the part of the isolation wall 12 which is located above the liquid level RL of the melt X. ，
An upper opening 17 is formed with 16 connected and wide open.

In the glass melting furnace having the above structure, the pair of main electrodes 3 is used as in the example of FIGS. 4 and 5.
The melt X is resistance-heated by energizing it, and the temperature is maintained thereafter.

At this time, the heat of the melt X is transferred to the inside of the auxiliary melting tank 13 by convection and diffusion, and the main melting tank 1
When the liquid level RL of the melt X is formed in both 1 and the auxiliary melting tank 13 and the temperatures of the melt X in the main melting tank 11 and the auxiliary melting tank 13 are the same, both liquid levels RL are the same. It becomes a level.

When a glass material is introduced from the raw material supply port 7 into the inside of the main melting tank 11 while applying a current between the main electrodes 3, the low temperature portion Y and the cold portion Y near the liquid level RL of the melt X are cold. Top Z is temporarily generated. At this time, since the temperature of the melt X hardly changes inside the auxiliary melting tank 13, the high temperature state is maintained.

More than the melt X inside the auxiliary melting tank 13,
When the low temperature portion Y and the cold top Z of the main melting tank 11 become relatively low in temperature, in addition to the heating action by the upward flow and convection of the melt X due to resistance heating between the main electrodes 3, Circulation and heat transfer of the melt X via the communication port 14 of the isolation wall 12 are performed. As shown by the arrows in FIGS. 1 and 3, between the main melting tank 11 and the auxiliary melting tank 13, the melt X is passed through the plurality of communication ports 14 of the isolation wall 12.
As a result of the circulation, the low temperature portion Y and the cold top Z are heated and gradually led to the extinguished state. The heat transfer to the cold portion Y and the cold top Z in this case is performed not only by the heat transfer from the lower side to the upper side but also by the heat transfer to the side.

In the example of FIG. 3, since the large upper opening 17 is opened in the isolation wall 12, in addition to the heat transfer due to the circulation of the melt X, the melt X inside the auxiliary melting tank 13 is also added.
Heat is radiated to the upper ceiling wall 6 to raise the temperature,
Further, by radiating downward from the ceiling wall 6, the low temperature portion Y is also heated from the surface. In this case, the heat transfer to the low temperature portion Y is performed not only from the lower side and the lateral side but also from the upper side, and the low temperature portion Y and the cold top Z are brought to the extinguished state.

When the glass material is charged into the main melting tank 11, the auxiliary electrode 3B (or the main electrode 3) and the side electrode 18 are energized so that the auxiliary melting tank 13 is charged. Auxiliary melting tank 1 is generated by resistance heating of melt X inside
It is also effective to form a relationship in which the inside of 3 has a higher temperature than the inside of the main melting tank 11. In this case, the above-mentioned heating of the low temperature portion Y and the cold top Z from the side and the above is effectively performed.

[0021]

As described above, the glass melting furnace according to the present invention has the following effects. (1) A main electrode that causes the melt to generate resistance heat by energization,
Auxiliary melting tank arranged on the side of the main melting tank and separated by a separating wall, and a plurality of auxiliary walls arranged on the separating wall at the bottom position of the auxiliary melting tank and near the liquid level of the melt to connect the insides of both tanks By adopting a configuration including a communication port of, the molten material in a high temperature state is circulated and supplied from the auxiliary melting tank to a low temperature portion or the like generated when the glass raw material is dropped into the molten material,
The operation efficiency can be improved by adding the heat supply from the side. (2) By adopting a configuration in which an upper opening that connects the internal spaces of both tanks is opened in the isolation wall above the liquid level of the melt, it is possible to protect the low temperature part from both above and lateral directions. It is possible to add heat supply to shorten the generation time of the cold top, reduce the non-uniform phenomenon of the current distribution, enhance the stability during operation of the glass melting furnace, and increase the operation efficiency. (3) By adopting a configuration in which a side electrode for heating the melt by heating the melt by heating is provided in the auxiliary melting tank, resistance heating of the melt in the auxiliary melting tank is added to melt inside the auxiliary melting tank. By increasing the temperature of the material, it is possible to frequently supply heat to the low temperature portion and quickly bring the glass material into a molten state. (4) By adopting a configuration in which a liquid level meter for measuring the liquid level of the melt is arranged in the auxiliary melting tank, even if a low temperature part is formed in the main melting tank, the liquid in the auxiliary melting tank The total liquid level can be detected by measuring the level.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a first embodiment of a glass melting furnace according to the present invention.

FIG. 2 is a plan sectional view showing a first embodiment of a glass melting furnace according to the present invention.

FIG. 3 is a side sectional view showing a second embodiment of the glass melting furnace according to the present invention.

FIG. 4 is a front sectional view showing a conventional example of a glass melting furnace.

FIG. 5 is a plan sectional view showing a conventional example of a glass melting furnace.

[Explanation of symbols]

 2 Side wall 3 Main electrode (electrode) 3B Auxiliary electrode 4 Bottom wall 5 Bottom electrode 6 Ceiling wall 7 Raw material supply port 8 Discharge port 9 Downflow nozzle 10 Inclined inner wall surface 11 Main melting tank 12 Isolation wall 13 Auxiliary melting tank 14 Communication port 15, 16 Internal Space 17 Upper Opening 18 Side Electrode 19 Liquid Level Meter X Melt RL Liquid Level (Liquid Level) Y Low Temperature Part Z Cold Top

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C03B 5/02

Claims (4)

[Claims] 1. A main electrode for causing a melt contained in the main melting tank to generate resistance heat by energization, an auxiliary melting tank disposed on a side portion of the main melting tank and separated by a partition wall, and a bottom portion of the auxiliary melting tank. A glass melting furnace, comprising: a plurality of communication ports, which are arranged on a partition wall at a position and a position near the liquid level of the melt and connect the insides of both tanks. 2. The glass melting furnace according to claim 1, wherein an upper opening connecting the internal spaces of the two tanks is opened in the isolation wall above the liquid level of the melt. 3. The glass melting furnace according to claim 1, wherein the auxiliary melting tank is provided with a side electrode for heating the melt by resistance heating. 4. A glass melting furnace according to claim 1, 2 or 3, wherein a liquid level meter for measuring the liquid level of the melt is arranged in the auxiliary melting tank.