JPS6022649B2 - How to add glass raw materials - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement in a method of charging glass raw materials.

Conventionally, various methods have been attempted in order to improve the melting ability and melting speed of glass melting furnaces.

For example, methods of forming glass raw materials into pellets or briquettes, adjusting the particle size of the raw materials, and using child heat of the raw materials have been proposed for a long time.

A method has also been proposed in which glass raw materials are compressed using rollers, etc. to increase their apparent specific gravity to about twice that of ordinary glass raw materials, and then charged into the furnace (Japanese Patent Application Laid-Open No. 48-30716, Akira Mochiseki). 51-41712). In addition, a method has also been proposed in which the glass raw material charged onto the molten glass is divided in the middle direction and separated into log shapes in the middle direction as the glass raw material layer advances (USP 2533826: Japanese Patent Application Laid-Open No. 50-940
No. 11).

However, these conventional methods have the disadvantage that either they are not sufficiently effective or require a huge amount of equipment investment, making it difficult to adopt them industrially. The present invention is a novel method that can improve melting capacity and melting speed and reduce dust (carry-over) in the furnace by processing the glass raw materials charged into the glass melting furnace using a relatively simple device. Provides a method for introducing glass raw materials. In the method of charging glass raw materials of the present invention, glass raw materials are continuously charged in layers onto molten glass in a glass melting furnace, and during melting, the glass raw materials are advanced over the molten glass in the vicinity of the input port of the glass melting furnace. The layer is successively pressed and compressed downward by a frit pressing member that has a pressing surface at the lower end and extends in the direction of the furnace, and periodically moves up and down, thereby compressing the frit layer. It is characterized in that a trout shearing force is applied between a compressed portion and a portion adjacent to the compressed portion to generate cracks in the glass raw material layer. As is well known, a batch which mainly consists of glass raw materials is a mixture of powder particles of various glass component raw materials, and the layers fed into a glass melting furnace in layers are loose aggregates containing a large amount of air. Due to the air contained in the raw material layer, it has high heat insulation properties, making it difficult for the temperature within the raw material layer to rise, and it takes a long time to melt. However, it is known that compressing glass feedstock improves heat transfer and reduces the time required to melt the same amount of feedstock.
On the other hand, one method for promoting the melting of the frit layer in a glass melting furnace is to provide peaks or valleys on the surface of the frit layer so that the melted glass is melted on the top surface of the layer by heat applied from the combustion space above the raw material layer. There is also a known method for preventing the phenomenon of blocking heat transfer by reflecting the heat stagnant in the air (USP 4).
030905).

According to this method, the molten glass flows down the sloped surface of the mountain-shaped portion of the raw material layer, exposing a new raw material surface, thereby promoting heat transfer from the combustion space. According to the present invention, the frit layer on the molten glass is sequentially pressed inward by a pressing member having a pressing surface at the lower end, and the frit layer is compressed using the buoyancy of the frit layer as a reaction force. Go.

As a result, a rock breaking force is applied between the compressed portion and the portion adjacent thereto, potentially causing cracks mainly in the middle direction inside the glass raw material layer. As a result, as time passes, the frit layer advances toward the center of the glass melting furnace.
As the melting process progresses, the above-mentioned cracks become apparent in the glass raw material layer, promoting the division of the glass raw material layer, resulting in a large number of log-shaped logs extending in the middle direction, or these are further divided in the vertical direction to form floating glass raw material layers in the form of small islands. This shortens the glass melting time. Thus, according to the present invention,
The effects of the two measures mentioned above are achieved simultaneously and organically.

Furthermore, according to the present invention, so-called carryover in a glass melting furnace can be significantly reduced.

In other words, in Siemens-type glass melting furnaces in which heat is recovered in a heat storage chamber, there are always problems such as clogging of the heat storage chamber due to scattering of powder raw materials and corrosion of refractory bricks in the heat storage chamber mainly due to alkali components of the powder raw materials. However, the lifespan of the heat storage chamber often determines the lifespan of the entire furnace. However, according to the present invention, the glass raw material layer is compressed near the inlet of the furnace, and the scattering of powder raw materials is reduced to about half or less, thereby extending the life of the glass melting furnace and reducing the load on the exhaust gas dust collector. became possible. In the present invention, the pressing member used to press and compress the glass raw material layer (which may be composed only of powdered raw materials, ie, batches, or may include glass cullet mixed therein) is The lower end surface constituting the pressing surface is preferably a flat surface or an upwardly convex or concave shape, and is an elongated rod-shaped body extending in the direction of the frit layer.

The pressing member may be made of a heat-resistant heavy object such as a refractory, a refractory concrete IJ block, or a metal body,
It may be a water-cooled box in which cooling water circulates inside. The pressing member is connected to an elevating mechanism that repeats a reciprocating movement of lowering and raising in order to sequentially press downward and compress the glass raw material layer introduced in layers from the raw material immersion machine onto the molten glass surface. Various types of mechanisms can be adopted as this mechanism. For example, the pressing member can be suspended from a piston rod of a hydraulic or pneumatic cylinder, and the pressing member can be lowered and raised by driving the cylinder. It is also possible to support the pressing member from above using a link mechanism such as a "magic hand" and to operate the link mechanism using a drive device provided at the upper end of the link mechanism to cause the pressing member to reciprocate up and down. FIG. 1 shows a plan view of the vicinity of the input port of the glass melting furnace, and FIG. 2 shows a cross-sectional view. In the figure,
Reference numeral 1 indicates the rear side of the melting side of the glass melting furnace, and reference numeral 2 indicates an inlet for glass raw materials provided at the rear end.

Reference numeral 3 denotes a feeder for glass feedstock, which feeds the glass feedstock onto the molten glass 4 at the feed port. 5 shows the frit layer thus formed, which is progressively advanced.

6 indicates a pressing member for the frit layer, which is a heavy object having an inside that is almost the same as the inside of the frit layer, and its thickness is:
For example, 10 to 100 skins.

In this example, the pressing section is made of a refractory block and is suspended from a piston rod of a hydraulic cylinder by a chain 8 via a pulley 9. The pressing member is lowered to press the frit layer 5 downward by its own weight, compressing it, and then making upward and downward reciprocating movements continuously or intermittently. In this way, the volume of the frit layer is reduced to about 40 to 90%, and a crack 10 is potentially generated in the middle direction as shown by the dotted line in the frit layer that has passed under the pressing part. is latent at the initial stage of melting, but as the melting progresses and the raw material layer becomes thinner as the frit layer advances, it becomes apparent, and the frit layer is finally divided into log-shaped or island-shaped lumps 11. When the method of the present invention was applied to a plate glass melting furnace with a glass capacity of 800 tons and a production rate of 200 tons/day (planar dimensions of the melting tank: medium 8 m x length 2 mm), the glass raw material layer melted and disappeared. The so-called mountain fall line has receded by about 3 hours, and the amount of soot and dust in the exhaust gas flue has decreased by about 44%.

Similarly, the glass capacity is 1200 tons and the production volume is 400 tons/
In the case of the day plate glass melting furnace (planar dimensions of the melting tank: Zhongxianh x length 3m), the drop line was moved back by 4m, and the amount of soot and dust in the exhaust gas was reduced by 53%.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the latter half of the melting tank of the glass melting furnace;
FIG. 2 shows a cross-sectional view. 1... Melting tank, 2... Inlet, 3... Inserting machine, 4... Molten glass, 5... Glass raw material layer,
6...Press member, 10...Crack, 11...
...A lump of glass raw material. Tsutomu'zu 2 illustrations

Claims (1)

[Claims] 1. When glass raw materials are continuously introduced and melted in layers onto molten glass in a glass melting furnace, the glass raw material layer that advances on the glass is shaped so that it has a pressing surface at the lower end and extends in the width direction of the furnace. A glass material pressing member having a glass material and periodically moving up and down sequentially presses and compresses it downward, so that there is substantially no uncompressed portion in the material layer, and the compressed portion of the glass material layer is compressed. A method for introducing glass raw material, characterized in that shearing force is applied between the compressed portion and an adjacent portion to generate potential cracks in the glass raw material layer.