Abstract: A method useful with oxy-fuel combustion and in a furnace which contains molten material, wherein either substoichiometric or superstoichiometric combustion and low velocity injection of fuel and primary and secondary oxidant in an oxy-fuel burner are carried out in an orientation which forms either a reducing or oxidizing atmosphere proximate the molten surface.

Abstract: A method of forming high strength glass fibers in a refractory lined glass melter is disclosed. The refractory lined melter is suited to the batch compositions disclosed for the formation high modulus, and high-strength glass fibers. The glass composition for use in the method of the present invention is up to about 70.5 Weight % SiO2, 24.5 weight % Al2O3, 22 weight % alkaline earth oxides and may include small amounts of alkali metal oxides and ZrO2. Oxide based refractories included alumina, chromic oxide, silica, alumina-silica, zircon, zirconia-alumina-silica and combinations thereof. By using oxide based refractory lined furnaces the cost of production of glass fibers is substantially reduced in comparison with the cost of fibers using a platinum lined melting furnace. Fibers formed by the present invention are also disclosed.

Abstract: Provided are an apparatus and method for manufacturing a solidified salt that is easy to treat in size and shape by using a vacuum transfer and a dual vessel. In the apparatus for quantitative solidification of a molten salt, a molten salt is introduced into a first vessel, and a second vessel is disposed inside the first vessel and quantitatively supplied with the molten salt. A molten-salt transferring unit quantitatively transfers the molten salt from the first vessel to the second vessel by vacuum pressure. A valve controls a discharge of the molten salt from the second vessel. A mold receives the molten salt from the second vessel and solidifies the molten salt. Accordingly, the molten salt can be stably discharged to the mold by quantitatively transferring the molten salt at vacuum pressure within the dual vessel, and a predetermined size and shape of the solidified salt can be manufactured, thereby processing and collecting the solidified salt safely.

Abstract: A glass melting furnace has a gas inlet positioned proximate to a charging section oxy-fuel combustion region to introduce gas into the region and to at least partially displace gas having a partial pressure of alkali vapor from the region, and optionally a gas outlet is adapted to provide an exit for a volume of furnace atmosphere. A method for reducing alkali vapor corrosion of glass furnace refractory structures includes providing a gas inlet proximate to the oxy-fuel combustion region; introducing a volume of gas from the inlet into the region, displacing a volume of gas having a partial pressure of alkali vapor from the region; and, optionally providing a gas outlet adapted to provide an exit for a volume of furnace atmosphere.

Abstract: A vacuum degassing apparatus for molten glass includes a vacuum housing which is evacuated to be depressurized therein; a vacuum degassing vessel which is provided in the vacuum housing to vacuum-degas molten glass as the molten glass flows therein; an uprising pipe which connects to the vacuum degassing vessel, and sucks and draws up undegassed molten glass to introduce the undegassed molten glass into the vacuum degassing vessel; and a downfalling pipe which connects to the vacuum degassing vessel and draws down the degassed molten glass from the vacuum degassing vessel to discharge the degassed molten glass. The cross sectional area of the path at the upper end portion of the uprising pipe is larger than the cross sectional area of the path at the lower end portion of the uprising pipe.

Abstract: A process for melting and refining vitrifiable materials, such that all or part of the thermal energy necessary for melting the said vitrifiable materials is supplied by the combustion of fossil fuel(s) with at least one oxidizer gas, the fuel(s)/gas or the gaseous products resulting from the combustion being injected below the level of the mass of vitrifiable materials (7). The refining of the vitrifiable materials after melting comprises at least one step of subjecting them to subatmospheric pressure while centrifuging.

Abstract: A glass making process comprising a step of fining the molten glass in a fining vessel comprising a top wall portion not in direct contact with the molten glass, and a side wall portion in direct contact with the molten glass, wherein the top wall portion has a temperature T(top), the side wall portion has a temperature T(side), and T(top)?T(side)?10° C., and a glass fining system. The invention is particularly useful for glass fining systems comprising a metal fining vessel made of precious metals such as Pt and/or Pt—Rh alloys.

Abstract: A front end for a glass forming operation comprises an open channel and at least one burner. The channel has at least one surface. The surface has at least one hole therein. The burner is oriented in the hole at an acute angle relative to the surface. In another embodiment of the invention, the channel has a top and a pair of sidewalls each having a surface. At least one hole is in at least one of the surfaces. The hole is at an acute angle relative to at least one surface. The burner is an oxygen-fired burner. In yet another embodiment of the invention, the top and sidewalls each have a super structure surface constructed of refractory material. The channel has an upstream end and a downstream end. At least one of the surfaces has a plurality of holes therein. The burners extend at an acute angle relative to at least one surface and in a plane extending between the upstream end and the downstream end and perpendicular to at least one surface. Oxygen-fired burners extend axially through corresponding holes.

Abstract: A charged glass raw material B is melted in a melting tank 10 by heating with a burner 31 and by heating with electrodes 12, to form molten glass G. Then, the molten glass G flows into a tank additionally provided as a noble gas dissolving tank 20 through a throat 40. The noble gas dissolving tank 20 is provided with a noble gas dissolving device 53, and the noble gas dissolving device 53 is provided with sixteen noble gas inlets 22 for introducing a helium or neon gas supplied to a hearth through heat resistant gas introduction tubes 21 into the noble gas dissolving tank 20. Bubbles of a helium gas A having a purity of 99% are blown out from the noble gas inlets 22 in volumes such that the bubbles have an average diameter of 80 mm or less in the molten glass G.

Abstract: A melter including an upper chamber configured to receive marbles or the like, and a lower chamber separated from the upper chamber by a porous wall through which, as the result of heating, glass marbles or the like liquefy in the form of a batch. The upper and lower chambers define a melting zone. A refining zone is fed via at least one channel emerging from the melting zone.

Abstract: A supplying tube 2 of a molten glass, which is placed in a downstream end portion of a supplying passage directing the molten glass flowing out of a melting furnace to a forming vessel 1a in a forming furnace 1, has a small diameter tube portion 2a which has a small flow passage area and is provided at an upstream side, and a large diameter tube portion 2c which is provided at a downstream side of the small diameter tube portion 2a and has a large flow passage area. An expanded diameter tube portion 2b of which flow passage area gradually expands toward the downstream side is interposed between the small diameter tube portion 2a and the large diameter tube portion 2c. The small diameter tube portion 2a, the expanded diameter tube portion 2b, and the large diameter tube portion 2c may be integrally and continuously connected to one another.

Abstract: A glass-melting furnace (10) has an upstream end (6), a downstream end (8), and a roof (22). The upstream end is positioned upstream of the downstream end. A charger (32) is provided to supply glass-forming material (30) to the upstream end of the furnace. At least one burner (34) is provided to supply heat to the glass-forming material at the upstream end of the furnace. An exhaust (60) is in communication with the downstream end of the furnace, with the exhaust being positioned downstream of the at least one burner.

Abstract: Bubbles of uniform diameter of 0.5 to 4 cm of gas such as helium are formed and pass into liquid such as molten glass by accumulating a sufficient volume of gas through a flow restriction into a space upstream of the point of injection at a controlled flow rate.

Abstract: A method and an apparatus for the rapid melting of glasses in a skull crucible is provided. The method and apparatus introduce high-frequency energy into the contents of the crucible by means of a coil arrangement surrounding the skull crucible, in order to heat the melt, and the batch is laid and the molten glass discharged in the upper region of the crucible, and undissolved constituents of the batch are retained by means of a cooled bridge which is immersed in the melt. The glass is taken off above the coil arrangement and is fed for further processing without flowing through the coil region.

Abstract: A front end for a glass forming operation including an open channel and at least one burner. The channel surface has at least one burner port and a burner oriented in the burner port at an acute angle relative to the channel surface. The surface may be a top, side or end wall and the burner port is at an acute angle relative to the surface of the wall.

Abstract: The present invention provides a A metal conduit for molten glass and a vacuum degassing apparatus are disclosed, which are capable of coping with extension and contraction, and vibration. By disposing at least one convex portion 20 so to have a height of 4 mm or above in a radial direction and continuously extend in a peripheral direction, it is possible to absorb thermal expansion and contraction without changing the entire length of the metal conduit 10 and to suppress from the metal conduit 10 from vibrated even when molten glass 121 is conveyed by the metal conduit. By employing the metal conduit 10 stated earlier in an upstream conveying pipe 130A, an uprising pipe 122U, a vacuum degassing vessel 120, a downfalling pipe 122L, a downstream conveying pipe 130B or the like in a vacuum degassing apparatus 30, it is possible to cope with thermal expansion and contraction, and vibration caused when conveying molten glass 121.

Abstract: A conduit for molten glass, a molten glass degassing method and a sub-atmospheric apparatus are provided, which are able to produce homogenous and good quality glass at low cost. A conduit for molten glass, which is capable of flowing molten glass in a horizontal direction, and to which vertical pipes are connectable, is disposed in a substantially horizontal direction. The conduit for molten glass can increase the area of a free surface of the molten glass by setting a width W at a larger value than a height H in cross-section and having an outline in cross-section comprising a convex curve. When the conduit for molten glass thus configured is used as a sub-atmospheric apparatus, it is possible to degas the molten glass effectively. Additionally, it is possible to have a sufficient strength since the convex curve forming the cross-section is elliptical. Further, it is possible to reduce costs by decreasing the amount of metal required for forming the cross-section.

Abstract: In the method and system for producing glass reduction of reduction-sensitive ingredients in the glass is reduced or preferably is avoided during the melting and fining processes. The glass preferably has a high refractive index. During the process an oxidizing agent is inducted into a fining vessel and preferably also into a melt crucible made of a slit skull that is cooled by a cooling agent. The oxidizing agent is preferably oxygen. Furthermore a system for conducting the method is also described.

Abstract: The invention relates to an apparatus and a method for low-contamination melting of high-purity, aggressive and/or high-melting glass or glass-ceramic. According to the invention, for this purpose a melt is heated in a crucible or melting skull crucible by means of high-frequency radiation and is mixed or homogenized in the melting crucible. It is preferable for a gas nozzle, from which gas bubbles, e.g. oxygen bubbles (known as O2 bubbling), escape into the melt, to be provided at the base of the crucible. This alone makes it possible to achieve surprising multiple benefits in the melting skull crucible. Firstly, unmelted batch which drops into the melt in solid form, for example from above, is melted down more quickly as a result of more intensive mixing with the liquid fraction of the melt, secondly the temperature distribution in the melt is made more even, thirdly a uniform distribution or mixing of different glass constituents is achieved, and fourthly the redox state of the glass can be adjusted.

Abstract: A process for producing a high-quality glass from highly reactive raw materials and a glass-melting apparatus for use therewith, comprising the step of charging a material for the glass to a molten glass in a heated vessel, (1) wherein an oxidizing gas is bubbled in the molten glass and a glass raw material that behaves as a reducing agent during being melted is charged into a position of the bubbling or (2) said vessel is filled with a dry ambient gas and while the ambient gas is allowed to flow to a liquid surface of the molten glass along an charging route of the glass raw material, the glass raw material is charged.

Abstract: The basic shape of the molten glass fining apparatus of the present invention is preferably either an elliptical or a somewhat rectangular shape such that the flow is more uniform and the bubbles have less distance to rise to the surface. A novel baffle design is also shown. The present invention improves the fining capability of the apparatus without increasing the cost of construction materials. In fact, the cost may be reduced.

Abstract: A method and system feed and burn pulverized fuel, such as petroleum coke, in a glass melting furnace having burners associated with sealed regenerative chambers which act as heat exchangers. The system supplies the pulverized fuel for melting glass raw materials. The emissions of flue gases produced by the combustion process of the fuel in the furnace are controlled in order to maintain clean the flue gases and for reducing the emission of impurities from the fuel such as SOx, NOx, and particulates. The regenerative chambers are manufactured with selected refractories such as magnesium, zircon-silica-alumina, or magnesia and zirconium-silicate, for counteracting the erosive and corrosive effects produced by the combustion process of the fuel in the glass melting chamber. A burner feeds the petroleum coke and simultaneously mixes a primary air and pulverized fuel-air mixture for the burning of the pulverized fuel.

Abstract: The invention relates to a method and a device for producing colored glasses. The aim of the invention is to obtain a paricularly intimate mixture and to enable a quick change of the melt at the same time. To this end, the following procedure steps are applied: a melt made of a compound or fragments of glass is produced, the glass melt is further processed in at least one additional vessel, the melt is supplied to a skull device (3) (skull pot or skull channel) during subsequent processing, a dye is supplied (6, 6.1) to the melt after the melt was in the melting station (1) but before the melt enters the skull device (3) or while said melt is in the skull device.

Abstract: The invention concerns a process and a device from the production of molten glass. According to the invention, measures will be taken to lead the current of the molten glass through the tank furnace so that cutoffs of the glass current between the surface of the glass bath, on the one hand, and the outlet opening on the other hand are avoided and a an equal holding period of all melt particles in the tank furnace is achieved.

Abstract: The invention relates to a method for changing glass compositions in continuously operated melting installations which has a significantly shortened melt changeover time and therefore lower costs and in which the glass quality is not adversely affected.

Abstract: A molten glass supply device is provided, which can solve unavoidable problems for high viscosity characteristics in connection with the conventional molten glass supply device for high viscosity glass. Such problems include improperly high heating cost caused by excessive heat radiation in a melting furnace, reduction in the grade of products deriving from an excess amount of an erosion foreign material and reduction in the product yield. High viscosity molten glass having a property in which a temperature at which the molten glass exhibits a viscosity of 1000 poise is 1350° C. or higher is supplied to a forming device through a melting furnace, a distribution portion in communication with the outlet of the melting furnace, and a plurality of branch paths branching from the distribution portion. In the branch paths, distribution resistance providing portions that provide distribution resistance to molten glass passed through the branch paths are provided.

Abstract: The present invention provides devices for glass melt devlivery and methods for using these devices. In these devices, a delivery nozzle comprising at least one platinum group metal material is directly heated by electricty. To facilitate heating, a cylindrical heating ring is mounted in ceramic base. The device's construction ensures a regulatable heating of the nozzle and the melted glass flux.

Abstract: A fused silica production furnace and methods of producing fused silica are disclosed. The furnace and the methods involve using a foamed refractory having a network of interconnected pores.

Abstract: The invention relates to a skull pot (1) for melting, crystallizing or refining inorganic substances. Said pot comprises a pot wall (1.1), a pot bottom (1.2), an induction coil (2) which surrounds the pot wall (1.1) and by means of which high-frequency energy can be coupled into the content of the pot. The pot wall (1.1) is formed by a ring of metal pipes which can be connected to a cooling medium. Slits are embodied between adjacent metal pipes. The bottom (1.2) is provided with a discharge for the melt (3). A sleeve (4) is allocated to the discharge. The admission end (4.1) of the sleeve (4) protrudes far into the inner chamber of the skull pot (1) in such a way that, during use, the melt (3) can be withdrawn through the crystallized bottom layer (3.3) in a controlled manner without the danger of impairing quality.

Abstract: This invention relates to a device for melting or refining glass or glass ceramics. According to the invention, such a device is provided with the following characteristics: a channel which is arranged in an essentially horizontal manner and which is provided with an inlet and an outlet for the glass melt; and an HF coil for coupling HF energy into the melt is allocated to the channel. The channel is made of a plurality of metal pipes in a similar way to a skull pot. Said pipes can be connected to a cooling medium.

Abstract: The invention relates to a skull pot for melting or refining glass or glass ceramics, comprising a pot wall (1), a pot base, and an induction coil (3) which surrounds said pot wall and through which high-frequency energy can be coupled into the contents of the pot. The pot wall is made up of a ring of metal pipes (1.1) which can be connected to a cooling medium, slot-type intermediate chambers being provided between adjacent metal pipes. The pot base has a run-off for the melt. The metal pipes (1.1) that form the pot wall (1) arm short-circuited with each other above the base in order to increase the degree of efficiency of the skull pot and especially, in order to even out the temperature profile of the melt throughout the depth of the melt.

Abstract: The invention relates to an in-line process for producing high-temperature stable glass. A sizing composition is advantageously used to reduce plasticizing between the resinous matrix and the glass fibers. The in-line process uses a melter or furnace apparatus, including a top charging and melting section and an intermediate flow regulator section having a baffle system improving the heat pattern across the glass flow, and a bushing having a tip plate for receiving molten glass from a furnace. The bushing has an enlarged size that allows drawing of a significantly increased number of glass fibers at one time. The fibers have essentially no catenary and may be wound to create a tightly wrapped package of glass fibers of uniform exterior diameter throughout their width. High-strength, high-silica fiber made according to the invention may be advantageously used in filament-winding, pultrusion and weaving processes.

Abstract: The present invention is to provide an all-electric glass-melting deep furnace and a method of refining and supplying glass in which high-quality molten glass can be efficiently produced in large quantity at high heat efficiency. An all-electric glass-melting deep furnace 20 has a bottom 2 and a side wall 4 constructed by piling up fireproof bricks 3 on the perimeter of the bottom 2. A height H of the side wall 4 is set to be twice or more than twice as long as an inside dimension D of the bottom 2 of the furnace. Since the furnace 20 is deep, there can be achieved a thick batch layer, a space in which glass is melted at high temperature, and a cooling area which is necessary to refine molten glass. The method of the present invention makes it possible to remove seeds which are generated when glass raw material are melted.

Abstract: A method and system for feeding and burning pulverized fuel, such as petroleum coke, in a glass melting furnace, which includes a glass melting and a plurality of burners associated with a pair of sealed regenerative chambers disposed side-by-side which act as heat exchangers, the burners are arranged in a series of ports that are associated with the glass melting region of the furnace. The system includes means for supplying the pulverized fuel by each one of the burners for melting glass raw materials. The emissions of flue gases produced by the combustion process of the fuel in the furnace are controlled in order to maintain clean the flue gases and for reducing the emission of impurities from the fuel such as SOx, NOx and particulates.

Abstract: The invention relates to a method for producing and/or preparing molten glass. The invention is characterised by the following: the molten glass flows in a container in a principal flow direction, the level of the molten glass being at a specific height above the base surface of the container; streams of a free-flowing medium are introduced into the molten glass in such way that said glass flows in spiral paths and that the axes of the spirals run parallel or approximately parallel to the principal flow direction; neighbouring inlet points of the streams are separated by a mutual distance, (viewed from the principal flow direction), of at least 0.5 times the height of the molten glass level.

Abstract: The invention relates to a device for melting or refining glass or glass ceramics. According to the invention, a device of this type is provided with the following characteristics: a plurality of tubes which are U-shaped and arrange side by side so that they form a cage like skull channel that is open on top, and a high frequency oscillation circuit which comprises an induction coil. The tubes can be connected to a cooling medium. The induction coil wraps around the channel in such a manner that winding sections extend along the lateral walls of the channel.

Abstract: The invention relates to a melting cistern for producing a glass melt as well as to its refining,

Abstract: A glass feeder comprises an enclosed chamber through which molten glass can pass, and passing through each side wall into the chamber at least one burner comprising first and second burner head means for combusting oxidant and fuel within said chamber so as to generate flames which extend in axially opposite directions along each side wall, adjacent and parallel to the side walls and adjacent the surface of the molten glass.

Abstract: The invention relates to a method and a device for refining a glass melt according to the skull pot principle. According to the invention, the inlet and outlet are located in the upper area of the crucible and lie diametrically opposite each other.

Abstract: The apparatus for refining a glass melt has a refining unit, which includes a horizontally extending refining section for removal of rising gas bubbles from the glass melt flowing through the refining section. So that the refining section can be shortened in contrast to a refining section in an apparatus with an open channel flow, the refining section according to the invention is formed so that the glass melt flow rate is higher over a substantial lengthwise portion of it near its bottom and lower near a surface of the glass melt flowing through it in comparison to the corresponding flow rates in an open channel flow for the same throughput. The refining section is advantageously at least partially covered with a fire resistant cover, which contacts the glass melt flowing through it and has at least one opening through which gas bubbles can escape. In addition the refining section may be provided with built-in elements shaped to provide the desired improved flow rate profile for the glass melt.

Abstract: A conveyor belt including a series of predefined sections and elevated support structures at the edges of each section for supporting items on the belt above the belt at each section.

Abstract: A method of making chalcogenide glass which utilizes liquid encapsulation to prevent the evaporation loss of low boiling point or high vapor pressure glass components while the glass melt is being processed.

Abstract: A drawing-off device (18) is used to empty a molten material (28) such as glass contained in a cooled crucible (10), in which there is an elongated pour orifice (30), a cooled slide valve (32) and a bar (36) forming a thermal bridge between the molten material (28) and the bottom (24) of the crucible (10), along one end (30a) of the orifice (30).

Abstract: Molten glass has a liquid level located at a higher level than lower ends of an uprising pipe and a downfalling. In addition, a contacting portion of the uprising pipe or the downfalling pipe and a brick receiver on an upstream or downstream pit for supporting the uprising or downfalling pipe, or a joint in the brick receiver is filled with sealing material.

Abstract: According to the invention, measures will be taken to lead the current of the molten glass through the tank furnace so that cutoffs of the glass current between the surface of the glass bath, on the one hand, and the outlet opening on the other hand are avoided and a an equal holding period of all melt particles in the tank furnace is achieved.

Abstract: A device for the melting of highly pure optical glasses and/or for the treatment of melts is provided. The device is intended for a subsequent refining or homogenization process making use of the skull technique. The device uses a number of coated metal tubes whose surface is free of glass-coloring ions.

Abstract: Glass is produced in a glassmelting furnace by combusting fuel and oxidant having an oxygen content greater than 80 vol. % oxygen in a melting zone to form molten glass, wherein the surface of the molten glass is exposed to the gaseous atmosphere in the melting zone and the water vapor content of the atmosphere at the surface of the molten glass is greater than 35 vol. %, and oxidant having an oxygen content greater than 80 vol. % is injected into the refining zone of the furnace under conditions to minimize mixing of said oxidant with gases above said oxidant and sweep water vapor at the surface of the molten glass into the melting zone to lower the water vapor content of the atmosphere at the surface of the molten glass.

Abstract: The invention relates to a device for purifying molten glass;

Abstract: In many engineering production processes, for example glass or glass-ceramic manufacturing processes, liquids, such as glass melts, participate in the processes in which gases are dissolved, which in part form bubbles in the liquid. So that the quality of the final product is not disadvantageously influenced, the liquid, e.g. glass melt, should be refined to remove the bubbles. According to the method of the invention an overpressure acting on the liquid is provided which is such that the internal pressure in the bubbles immediately under the surface of the liquid in a refining chamber is at least as great as the sum of equilibrium pressures of the gases dissolved in the liquid and the sum of the vapor pressure of components evaporating from the liquid. A two stage apparatus is provided which performs a preferred embodiment of the refining method of the invention.

Abstract: This apparatus is a furnace for heating molten material which employs oxygen-fuel burner assemblies. Preferably, the assemblies are submerged in the molten material. They are water cooled top down units with burner nozzles being off-set from the supply column. The apparatus utilizes one or more burners for each top down supply column. The supply column and attached burners can be rotated or moved in a manner to avoid the open chimney effect seen with fixed air-fuel burners of the prior art. These burners with an off-set nozzle like the letter L are rotated at high speed or oscillated to distribute the combustion in the form of gas bubbles or a gas curtain. In another embodiment, the oxy-fuel burners are not submerged. The nozzles are aimed at unmelted batch or the upper surface of the molten material for controlled splashing.