JPS5918323B2 - Glass continuous melting furnace - Google Patents

Description

[Detailed description of the invention] The present invention relates to a continuous glass melting furnace.

Conventionally, melting furnaces with an inlet for glass raw materials on one side and a molten glass outlet on the other side have been used for continuous melting of glass, but a single-tank melting furnace is difficult to melt raw materials and remove bubbles. Because of this, many melting furnaces consist of two types: a melting tank and a subsequent clarification tank.

In this case, the bottoms of conventional two-tank melting furnaces are both flat, so when manufacturing another type of glass after manufacturing one type of glass, there is a large amount of the previous type of glass remaining. Therefore, when manufacturing the following types of glass,
The disadvantage is that the quality of the glass deteriorates, or else a large amount of glass must be produced in vain for cleaning in the first place, and that metal lead, which is produced when a part of the raw material is reduced, stagnates at the bottom. This has the disadvantage that it corrodes the furnace material and shortens the life of the furnace.

On the other hand, a melting tank and a clarification tank are installed one above the other in the same furnace,
A melting furnace has also been proposed in which the bottom is funnel-shaped, foreign matter heavier than the molten glass in the furnace is excreted from the tip, and the molten glass is taken out from an outlet provided at the top of the tip. (Refer to Special Publication No. 49-25170)
.

However, in this type of one-piece melting furnace, melting and clarification are carried out in the same tank while flowing continuously from top to bottom in the vertical direction, so the melt tends to leave residue and bubbles and the clarification effect is not sufficient. The drawback is that high quality glass cannot be obtained.

Therefore, an object of the present invention is to provide a continuous glass melting furnace that has a sufficient fining effect, can produce high quality glass, and has an extended service life by reducing erosion at the bottom of the melting furnace. .

In the present invention, in a continuous glass melting furnace, which is composed of a melting tank and a clarification tank that are adjacent to each other across a partition wall, and the melting tank and the clarification tank are in communication through a throat opened at the center of the lower end of the partition wall, the melting process is performed. The above object is achieved by the tank having a funnel-shaped bottom having a foreign matter discharge port at the tip, and the clarification tank having a funnel-shaped bottom having the throat as the tip.

Next, the present invention will be specifically explained by examples with reference to the drawings.

FIG. 1 is a sectional side view of a melting furnace showing one embodiment of the present invention.

The melting tank 1 is adjacent to the clarification tank 2 with a partition wall 3 in between, and a throat 4 is opened at the center of the lower end of the partition wall 3, and the melting tank 1 and the clarification tank 2 communicate with each other through the throat 4. .

According to the present invention, the dissolution tank 1 has a funnel-shaped bottom 6 having a foreign matter discharge port 5 at its tip, and the clarification tank 2 has a funnel-shaped bottom 7 having the throat 4 as its tip.

When an appropriate amount of the prepared lead-based glass raw material is put into the raw material input port 8 of the melting furnace having the above structure, and the resistance heating element 9 is energized and heated to about 800 to 900°C, the molten glass becomes a good conductor. Next, electricity is applied between the electrodes 10a and 10b to further heat the electrodes.

The temperature of the dissolution tank 1 is usually 850 to 1450°C.

Since the molten glass is in a liquid state, it passes through the throat 4 to the clarification tank 2, and on the other hand, reaction products of the furnace material and glass generated in the melting tank 1, melted furnace material, metal lumps produced by reduction, etc. Heavy foreign matter gathers near the excretion port 5 due to the slope of the bottom 6.

Therefore, the foreign matter is occasionally removed by opening the discharge port 5 and heating it with a burner to fluidize it.

The molten glass that has proceeded to the clarification tank 2 is heated and clarified by a heating burner 11a and/or an rtiib such as a gas, kerosene, or heavy oil burner.

Heavy foreign matter generated during this clarification process collects in the throat 4 due to the inclination of the funnel-shaped bottom 7, and further passes through the throat 4 due to the inclination of the bottom of the throat 4 and the inclination of the dissolution tank bottom 6, and collects near the discharge port 5.

The temperature of clarification tank 2 is usually higher than that of melting tank 1,
The temperature is usually about 1000 to 1500°C.

The slope of the bottom 6 of the dissolution tank 1 and the bottom 7 of the clarification tank 2 is 15
The angle is preferably about 45 degrees, and the bottom surface of the throat 4 is also preferably inclined.

In particular, as shown in FIG.
It is preferred that the bottom surface of the fining tank 2 and the bottom 7 of the clarification tank 2 have the same slope.

The clarified molten glass naturally flows out from the outlet 12 under its own weight due to the height difference between the raw material input port 8 and the outlet 12.

Therefore, the outlet 12 should be provided at a lower position than the raw material input port 8.

When the glass raw material is continuously or intermittently introduced into the inlet 8, the glass raw material is melted, and the clarified molten glass continuously flows out from the outlet 12.

The molten glass flowing out from the outlet 12 is then transferred to a working tank, a platinum tank, or a storage tank (none of which are shown) depending on the purpose and type of use, and then shaped or stored.

Note that FIG. 1 shows a resistance heating element 9 and a directly energized heating electrode 10a.
Although the heating burner 11a is shown, the heating means in the melting furnace of the present invention is not limited to these, and any known means or a combination thereof can be employed.

For example, in heating the clarification tank 2, a direct current heating method and a burner heating method may be combined.

FIG. 2 is a cross-sectional view of the melting furnace shown in FIG. 1 taken along a plane perpendicular to the paper plane passing through line A--A in FIG. 1, viewed from above.

The resistive heating element 9 and the heating burners 11a and 11b are shown as imaginary drawings.

The tank on the left is the dissolution tank 1, and the tank on the right is the clarification tank.

In FIG. 2, the dissolution tank bottom 6 has an inverted quadrangular pyramid shape, but the present invention is not limited to this, and it is sufficient that it simply has a continuous slope from the bottom periphery toward the discharge port 5, so that it has an inverted conical shape. The bottom may have a shape similar to that of the bottom.

In Fig. 2, the bottom part 7 of the clarification tank is also drawn in the shape of an upside-down smaller shape obtained by dividing a truncated quadrangular pyramid along one side of the upper quadrangle along a perpendicular plane. In the present invention, the present invention is not limited to this.
Any bottom part may be used as long as it has a continuous slope toward the bottom surface.

Further, in FIG. 2, the shapes of the dissolution tank and the clarification tank are square, but the present invention is not limited to this, and may be, for example, hexagonal or substantially circular.

According to the present invention, the fining effect is sufficient, so high quality glass is produced, and the bottom of the melting furnace is less eroded, so the life of the melting furnace is extended, and when the production of one type of glass is stopped, Since almost all of the molten glass that cannot flow out from the outlet and remains in the furnace can be taken out from the foreign matter discharge port, the amount of remaining glass is extremely small, and the advantage is that the type of glass to be melted can be easily changed.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a melting furnace showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG. Explanation of symbols of main parts, 1...Dissolution tank, 2...
... Clarification tank, 3 ... Partition wall, 4 ...
Throat, 5... Foreign body excretion port, 6...
Dissolution tank reach limit 7...- Bottom of clarification tank, 8...
- Glass raw material inlet, 9...Resistance heating element, 10
a, 10b... a pair of directly energized heating electrodes, 11
a, 11b... Heating burner, 12...
- Molten glass outlet.

Claims (1)

[Claims] 1 Consists of a dissolving tank and a clarifying tank that are adjacent to each other across a partition wall,
In a continuous glass melting furnace in which a melting tank and a clarification tank are connected through a throat opened at the center of the lower end of a partition wall, the melting tank has a funnel-shaped bottom having a foreign matter discharge port at the tip, The continuous glass melting furnace is characterized in that the clarification tank has a funnel-shaped bottom with the throat as the tip.