DD216710A1 - GLASS MELTING PAN - Google Patents

Abstract

The invention relates to a glass melting tank with opposing aggregate insert and glass removal, which is heated with fuel and additionally with electrical energy, are introduced in the stabfoermige electrodes, in particular through the tub bottom. The melting performance and the glass quality is to be increased by transverse convection currents. In addition to the per se known arrangement of source area electrodes, heating electrodes or groups are arranged one behind the other along or near d. Schmelzwannenlaengsachse arranged between the source region and the insert-side end wall. Source area and heater electrode groups are connected to separate electrical energy feed systems. Within the groups, the electrodes are arranged at different distances and / or immersion depths. The invention is applicable to electrically additionally heated melting tanks for glass or similar substances.

Description

Title of the invention

'. 'it

Glass melting tank

Field of application of the invention

The invention relates to a continuous glass melting tank, in which the mixture is placed on 'one end and the melt is withdrawn at the opposite end, the heating combined with fuel and electric energy, but predominantly with, fuel takes place and the electrical energy over, in particular vertically through the Bottom led into the melt, preferably rod-shaped electrodes or electrode groups is unbound.

Characteristic of the known technical solution

The desire to increase the melting performance and the quality of the melt fuel-heated glass melting tanks, among other things has led to solutions in the source area - ie in that area that separates the melting and ι lauter zone - to arrange electrodes. , χ The conversion of electric energy in Joule heat in the melt is particularly effective for the formation of an intensive, directed in the tub longitudinal axis Konyektionsströmung, the glass of higher temperature transported to the melted mixture and a Durch-,.

mixture of the glass causes. ..

, . »« R% .--- ι r »

Such an arrangement is for example in DE-AS 1 069th

set forth ,. '. -

However, the intensive longitudinal convection flow suppresses the cross-flow of the glass, which is important for the homogenization. All the more so in modern, thermally well-insulated melting furnaces, where the cross flows are already low anyway «

Additional electrodes in the fusing zone, such as disclosed in U.S. Patent Nos. 3,108,149 and J) DW 69,673, enhance and assist the thermal barrier. Melting of the mixture, however, is not sufficient to overcome the above-mentioned problem. -

It is also known from DE-AS 1 471 992, in addition to the electrodes in the source region to arrange electrodes along the tub axis in the refining zone between the source area and the passage wall. Their use is intended to prevent insufficiently purified glass from leaving the molten bath through the passage.

In the case of this solution, too, there is a strong suppression of the transverse convection in the area between the batch deposit and the source area, whereby the necessary intensive mixing of the glass, which has been freshly melted in different areas, is not ensured.

Aim of the invention.

The invention pursues the object of increasing the melting performance when melting glass or similar silicate substances and improving the quality of the melt.

Presentation of the WeSeHS ₁ the invention

It is the object of the invention to provide means for continuously working, combined heated glass melting furnaces, which influence the transverse convection currents in the melting part, whereby in addition to the increase in melting efficiency, an intensive mixture of the melt and thus a better quality is effected «

According to the invention the object is achieved if in addition to a known arrangement of electrodes or groups in the source region transverse to the longitudinal axis of the glass melting tank for influencing the Querkonvektionsströmungen in 'molten pool heating electrodes or groups behind one another along or near the longitudinal axis of the GI as melting trough between the source area and the insert-side end wall are arranged _o

According to a further feature of the invention, the source region electrodes or electrode groups and the heating electrodes or electrode groups are connected to separate electrical energy supply systems » ^. In order to be able to vary the energy distribution in the electrode groups, it has proven expedient to arrange the electrodes in different, distances and / or different immersion depths. By these measures it is achieved that according to the tub geometry and the technological conditions the most expedient relationship between longitudinal and transverse convection flow can be adjusted and thus a significantly improved homogenization of the melt is ensured.

embodiment

_; With reference to schematic drawings embodiments will be explained in more detail.

- 4

ι show it; ,

Pig »1 a horizontal section through a glass melting tank in the upper third of the glass bath with convection flow path shown;

Pig "2 is a schematic representation of the power supply, for two separately controllable electrode groups of the glass melting tank j

Pig · 3 is a schematic representation of the power supply for three separately controllable electrode groups modified arrangement. ,

The glass melting tank consists of. the Schmelzbassin init the side walls 1, the passage wall 2 and the end wall 3 »on which the insertion stem 4 is located over which the Einlegegut is abandoned '.

The molten pool is filled with the melt 5. In the melt 5, the source area electrodes 6, which form a heating group transverse to the Sehmelzbassinlängsachse and the heating electrodes 7, which form at least one further heating group along Sehmelzbassinlängsachse, the »with the help of the source area electrodes 6 and the heating electrodes in the melt 5 introduced electrical energy is converted by the Jouleeffekt in heat ' energy. The heat energy released around the source area electrodes serves to stabilize the longitudinal convection flow 8 which is directed from the source area electrodes 6 to the passage wall 2 in the upper area of the melt 5 and from the passage wall 2 to the source area electrodes 6 in the lower area of the melt 5 upper region of the melt 5, a Längskonvektionsströmung 8 'influenced, which runs from the source area electrodes 6 to the end wall 3 and in the lower region of the melt 5 from the end wall to the source area electrodes 6 «

The Längskonvektionsströmung 8 'and 9 Querkonvektionsströmung add up vectorially to the resulting flow 10 _e in the lower region of the melt 5, the resulting flow 10 a opposite to the illustrated flow 10 opposite direction thereby almost closed flow cycles are achieved. By removing the melt 5 in the region of the passage wall 2, there is an exchange of the melt 5 between • resulting from the resulting flow 10; Flow cycles, The melt 5 has when .Leverlassen the molten pool, due to the described flow. , running, traveled a relatively long distance, thereby providing improved quality of Schmelze'erzielt is _{0 / s} Moreover, the flow pattern described allows a ^ increase in the melting capacity of the glass melting furnace ,, The separate controllability of the electrode groups showing the embodiment in Pigβ 2 "The source area electrodes 6 , introduced vertically and horizontally in the source region, are connected to the three-phase network 11 via the adjusting device 12 and the matching transformer .13. The outer source region electrodes 6 are connected in parallel. The heating electrodes 7 are connected to the three-phase system 11 via the adjusting device 12 'and the matching transformer 13 * connected and connected analogously to the source area electrodes 6 ».

The explained solution makes it possible with the adjusting devices 12; 12 ^{1 to set} the supplied powers of the electrode group of the source area electrodes 6 and the heating electrodes 7 independently of each other and thus longitudinal and Querkonvektionsströmung 8 'or 9 (Figo 1) the tub geometry and the technological conditions adapt «-,.

Another exemplary embodiment of the glass melting tank is shown in FIG. 3. The different energy distribution within the electrode group formed by the source area electrodes 6 is determined by different distances. '' '' ·. -.-. 6-

This can also be achieved by different immersion depth of the source region electrodes 6 and also of the heating electrodes.

The two electrode groups forming heating electrodes 7 are arranged one behind the other in the triangle near the molten pool longitudinal axis. Between the two Heizelektrodengruppen the different energy distribution is ensured by the connection of the heating electrodes 7 to the three-phase network via the adjusting devices 12 '$ 12 "and the matching, transformers 13'j 13".

The glass melting tank according to the invention can also be equipped with further additional heating electrodes, for example to assist the melting of the insert material. The arrangement of the additional heating electrodes and the fed power may only serve to assist melting and not affect the described Konvektionsströmungen in their effect on the melt 5.

The glass melting tank according to the invention is also suitable for melting other silicate substances without any restrictions. A shape of the glass melting tank deviating from the illustrated embodiment likewise does not affect the inventive solution.

Claims (3)

invention claim 1, Continuous working glass melting tank, in which the mixture is inserted at one end face and the. Melt is drawn off at the opposite end, the heating combined with fuel and electric energy, but predominantly with fuel and the electric energy, especially vertically discharged through the bottom of the molten pool, preferably bar-shaped electrodes or electrode groups is released, characterized in that in addition to per se known arrangement of source region electrodes (6) or Quellbereichelektroektrodengruppen transverse to the longitudinal axis of the glass melting tank for influencing a transverse, convection (9) in the molten pool in heating electrodes (7) 'or Heizelektrodengruppen behind one another along or near the longitudinal axis of the glass melting tank between the source region and the insert-side end wall (3) reasonable \ are arranged. 2 "Continuous working glass melting tank according to item 1, characterized in that the source area electrodes (6) or source area electrode groups and the heating electrodes (7) or heating electrode groups are connected to separate electric power feeding systems ''. ' - 8th ·* 3 · Continuous working glass melting tank according to items 1 and 2, characterized in that the source area and heating electrodes (6; 7) of an electrode group are arranged at different distances from one another and / or at different immersion depths »,. .. ' For this 3 pages drawing