Method of and apparatus for electrically heating molten glass

Claim 2

A CONTINUOUS GLASS MELTING FURNACE COMPRISING: A MELTING AND REFINING TANK HAVING A BATCH DELIVERY REGION, A GLASS REFINING REGION UNDIVIDED FROM SAID BATCH DELIVERY REGION AND SPACED ACROSS THE SURFACE OF THE GLASS CONSTITUENTS TO BE CONTAINED THEREIN FROM SAID BATCH DELIVERY REGION, AND A MOLTEN GLASS ISSUING REGION IN SAID GLASS REFINING REGION; SAID TANK HAVING A FIRST SIDE WALL REMOTE FROM SAID GLASS ISSUING REGION AND IN PART DEFINING SAID BATCH DELIVERY REGION, AND HAVING A SECOND AND THIRD SIDE WALLS EXTENDING FROM SAID FIRST SIDE WALL AND IN PART DEFINING SAID BATCH DELIVERY REGION; A PLURALITY OF BATCH DELIVERY MEANS LOCATED IN THE BATCH DELIVERY REGION FOR PROGRESSIVELY FEEDING AND DISTRIBUTING BATCH ALONG THE ENTIRE LENGTH OF SAID FIRST WALL INTO SAID BATCH DELIVERY REGION TO ADVANCE A COVER OF BATCH EXTENDING BETWEEN SAID SECOND AND THIRD WALLS ACROSS THE SURFACE OF THE MOLTEN GLASS CONSTITUENTS IN SAID TANK TOWARD SAID MOLTEN GLASS ISSUING REGION TO A LEADING EDGE INTERSECTING A FREE SURFACE OF EXPOSED MOLTEN GLASS, THE FREE SURFACE OF EXPOSED BATCH COVER COVERING A PREPONDERANCE OF THE MOLTEN GLASS WITHIN SAID TANK; AN ARRAY OF ELECTRODES EXTENDING INTO THE MOLTEN GLASS WITHIN SAID TANK AND DISTRIBUTED BETWEEN SAID BATCH DELIVERY AND GLASS ISSUING REGIONS OF SAID TANK TO PROVIDE THE PREPONDERANCE OF THE HEAT ENERGY FOR MLETING BATCH MATERIALS THEREIN;

Claim 3

A glass melting furnace according to claim 1 wherein said means for applying heat is a hydrocarbon fuel burner.

Claim 4

A continuous glass melting furnace comprising: a melting and refining tank which is generally rectangular in plan and has a width and a length substantially greater than said width; said tank having first and second batch delivery regions, a glass refining region undivided from said batch delivery regions and spaced across the surface of the glass constituents to be contained therein from said batch delivery regions, and a molten glass issuing region in said glass refining region; said batch delivery regions being at each of the opposed walls defining the ends of the length of said tank; said glass issuing region being in the vicinity of the center of the length of said tank and having a molten glass upper surface in the center of the length of the tank; a plurality of batch delivery means located in each batch delivery region for progressively feeding and distributing batch along the entire length of the respective opposed walls defining the ends of the length of said tank into said respective batch delivery regions to advance covers of batch extending across the surface of said tank and toward said molten glass issuing region between those side walls of said tank extending from said batch delivery regions to said glass issuing region, said batch surface extending to said glass issuing region and covering a preponderance of the molten glass within said tank, said batch having a leading edge between the center of the length of the tank and each of the opposed walls defining the ends of the length of the tank; an array of electrodes extending between said batch delivery and said glass issuing regions of said tank to provide the preponderance of the heat energy for melting batch material therein; a top on said tank extending between said batch delivery and glass issuing regions; said furnace having first and second flue ports in said respective first, and second batch, delivery regions above the level attained by batch and said top defining an open flow path from said glass issuing region to said flue ports; and active means for applying heat energy located above the glass constituents only in the region above said glass issuing region, said means being limited in its heating capacity to apply only sufficient heat to said exposed molten glass surface to promote the escape of gas evolved from the melted material through said exposed molten glass surface to the atmosphere beneath the top, whereby the evolved gas and atmosphere as it flows toward said flue ports applies heat energy to upper surface of the mass of batch to preheat the upper surface of the mass of batch to preheat The upper surface of said batch and to cool the evolved gas and atmosphere prior to its entry into said flue port.

Claim 5

A continuous glass melting furnace comprising: a melting and refining tank which is generally rectangular in plan and has a width and a length substantially greater than said width; said tank having first and second batch delivery regions, a glass refining region undivided from said batch delivery regions and spaced across the surface of the glass constituents to be contained therein from said batch delivery regions, and a molten glass issuing region in said glass refining region; said batch delivery regions being at each of the opposed walls defining the ends of the length of said tank; said glass issuing region being in the vicinity of the center of the length of said tank and having a molten glass upper surface in the center of the length of the tank; a plurality of batch delivery means located in each batch delivery region for progressively feeding and distributing batch along the entire length of the respective opposed walls defining the ends of the length of said tank into said respective batch delivery regions to advance covers of batch extending across the surface of said tank and toward said molten glass issuing region between those side walls of said tank extending from said batch delivery regions to said glass issuing region, said batch surface extending to said glass issuing region and covering a preponderance of the molten glass within said tank, said batch having a leading edge between the center of the length of the tank and each of the opposed walls defining the ends of the length of the tank; an array of electrodes extending between said batch delivery and said glass issuing regions of said tank to provide the preponderance of the heat energy for melting batch material therein; a top on said tank extending between said batch delivery and glass issuing regions; said furnace having first and second flue ports in said respective first, and second batch, delivery regions above the level attained by batch and said top defining an open flow path from said glass issuing region to said flue ports; and active means for applying heat energy located above the glass constituents only in the region above said glass issuing region, said means being limited in its heating capacity to apply only sufficient heat to said exposed molten glass surface to promote the escape of gas evolved from the melted material through said exposed molten glass surface to the atmosphere beneath the top, whereby the evolved gas and atmosphere as it flows toward said flue ports applies heat energy to upper surface of the mass of batch to preheat the upper surface of the mass of batch to preheat The upper surface of said batch and to cool the evolved gas and atmosphere prior to its entry into said flue port.

Claim 6

A glass melting furnace according to claim 3 wherein said means for applying heat energy is located in the central region of the length of the tank.

Claim 7

A glass melting furnace according to claim 4 wherein said means for applying heat energy is a plurality of gas burners adapted to distribute heat energy across the width of the tank centrally of the length of the tank.

Claim 10

The method according to claim 6 wherein said molten surface in the glass issuing region is heated to about 2000*F. and said hot gases are cooled in their flow across the glass batch surface to about 600*F., and including passing said cooled gases to a flue.

Claim 11

The method according to claim 6 wherein the heat from the localized source is applied by the combustion of hydrocarbon fuel.

Claim 12

The method according to claim 6 wherein the glass batch is fed to the surface of the molten glass from a side portion of the body.

Claim 13

The method according to claim 6 wherein the glass batch is fed to the surface of the molten glass from opposed side portions of the body and the molten glass is withdrawn from a region intermediate the opposed side portions from which batch is fed.

Claim 14

The method according to claim 6 including the step of maintaining a major portion of the glass batch on the surface of the molten glass free of the glaze.