Abstract: A melting and/or refining unit for conductively heatable melts, in particular glass melts, is provided. The melting and/or refining unit has a tank and at least one electrode. The electrode passes through an opening in a wall of the tank so as to be immersed in the conductively heatable melt. The melting and/or refining unit has an apparatus for reducing the local introduction of heating power into at least one region adjacent to the electrode.

Abstract: A high temperature industrial furnace roof system having first and second spaced apart hanger brick rows with a filler row disposed therebetween and a cable system including a plurality of electrical cables. The filler row includes a plurality of filler elements having at least one removable heating module with a heat source. The cable system operatively connects the heat source with a power source and permits the removable heating module to be removed from the respective filler element while the respective heat source remains operatively connected with the power source.

Abstract: A waste vitrification apparatus (10) having rotatable mixer impeller (16) functioning as a shaft electrode (60) and metallic vessel (14) functioning as a vessel electrode (62). A stream (12) of waste material and vitrifiable material are mixed and melted in the vessel (14) for vitrification. The waste vitrification method converts a feed stream (12) by mixing the feed stream into a glass melt (13) and melting glass batch of the feed stream (12) to form a foamy mass. The stream is dispersed by the impeller (16) to form a foam which is then densified in a settling zone (22), recovered through a spout (24) and solidified in storage containers. Means are provided to adjust the location of the mixing impeller (16) in the vessel (14) to change the depth of the settling zone (22). The impeller (16) is mounted on a drive shaft (18) having a recirculating coolant flow.

Abstract: A waste vitrification apparatus (10) having rotatable mixer impeller (16) functioning as a shaft electrode (60) and metallic vessel (14) functioning as a vessel electrode (62). A stream (12) of waste material and vitrifiable material are mixed and melted in the vessel (14) for vitrification. The waste vitrification method converts a feed stream (12) by mixing the feed stream into a glass melt (13) and melting glass batch of the feed stream (12) to form a foamy mass. The stream is dispersed by the impeller (16) to form a foam which is then densified in a settling zone (22), recovered through a spout (24) and solidified in storage containers. Means are provided to adjust the location of the mixing impeller (16) in the vessel (14) to change the depth of the settling zone (22). The impeller (16) is mounted on a drive shaft (18) having a recirculating coolant flow.

Abstract: An all-electric glass-melting deep furnace and a method of refining and supplying glass are disclosed in which high-quality molten glass is efficiently produced in large quantity at high heat efficiency. The 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 furnace makes it possible for the molten glass 6 to absorb fine seeds by its pressure and cooling effects that are produced when the seeds move downward to the bottom 2.

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 an energy supply device of a melting tank. According to the invention, between an electrode plane of the melting tank and a converter for the current supply of the electrode plane, a separatable plug connection is provided in the supply line, between the electrode plane and the converter. Thereby in case of a defect of the converter, the supply line can be cut off simply and rapidly, and the converter either tended to or replaced. In an especially advantageous form of execution the energy supply device has a reserve converter so that, on failing of the converter, by unplugging the plug connection and replugging it so as to set up a plug connection to the reserve converter, the energy feed to the electrode plane can be restored within the shortest possible time.

Abstract: The invention relates to an energy supply device of a melting tank. According to the invention, between an electrode plane of the melting tank and a converter for the current supply of the electrode plane, a separatable plug connection is provided in the supply line, between the electrode plane and the converter. Thereby in case of a defect of the converter, the supply line can be cut off simply and rapidly, and the converter either tended to or replaced. In an especially advantageous form of execution the energy supply device has a reserve converter so that, on failing of the converter, by unplugging the plug connection and replugging it so as to set up a plug connection to the reserve converter, the energy feed to the electrode plane can be restored within the shortest possible time.

Abstract: A furnace having a combustion chamber, a fuel inlet for the combustion chamber, an electric heater operatively coupled with the combustion chamber, an electric generator coupled to the electric heater, and an internal combustion engine for driving the electric generator. The internal combustion engine includes an exhaust and a conduit. The conduit couples the exhaust to the combustion chamber.

Abstract: A glass melting tank provides heat in a melting chamber 11 from pairs of electrodes 26, 27 and 28. A three-phase electrical power supply 34 provides power to the electrode pairs and the voltage supplied for the different phase is independently controlled by a power control 33.

Abstract: A melting apparatus in which a material to be melted is accommodated in a crucible made of platinum or its alloy, and electric current passes through the crucible to generate heat ot melt the material. At least a part of the crucible is formed into a double-wall structure having inner and outer peripheral walls. The electric current is caused to pass through the double-wall structure to generate the heat.

Abstract: An electric melting furnace for vitrifying waste, having a melting tank having walls of refractory bricks, the melting tank being provided at the upper portion thereof with a supply port for a glass additive and waste and at the bottom portion thereof with a discharge port for molten glass containing the waste; at least a pair of side electrodes horizontally provided on opposite side walls of the melting tank; and at least one central electrode having a polarity opposite to that of the side electrodes, the central electrode being horizontally positioned in the interior of the melting tank at substantially the middle portion between the side electrodes. By such melting furnace construction, as described above, the heating current selectively flows through between the side electrodes and the central electrode, and does not flow electrically conductive substances deposited on the furnace bottom.

Abstract: An apparatus and method for making electrical resistance measurements of individual powered electrodes within a glass heating furnace is disclosed. The powered electrodes are energized in pairs with electrical power supplied at a relatively low frequency, causing electrical currents flow between the pairs of powered electrodes through a pool of molten glass so as to generate heat therein. A single reference electrode is also provided within the furnace. Each of the powered electrodes is sequentially paired with the reference electrode to permit voltage and current measurements to be made. To accomplish such measurements, a relatively small high frequency electrical signal is supplied to the powered electrode, in addition to the relatively low frequency heating power supplied thereto. As a result, a measurement current flows between the selected powered electrode and the reference electrode.

Abstract: An electric melting furnace is described for melting high electrical resistivity glass, such as E-glass, within a melting chamber surrounded by a relatively low electrically resistivity refractory, such as chromic oxide refractory, by utilizing interconnected peripherally positioned batch electrodes at substantially the same potential as the chromic oxide walls and centrally positioned electrodes which are immersed a greater distance than the batch electrodes. A quiescent zone is formed adjacent a lower portion of the melting chamber and the batch blanket and effective hydrostatic head of the molten bath are adjusted by controlling the immersion of the batch electrodes within the molten bath.

Abstract: Disclosed is a method for protecting the heating electrodes of glass melting furnaces by applying a DC potential to various electrodes of the furnace. The DC current is applied to the heating electrodes through counter electrodes or anodes. The method of this invention not only reduces the corrosion of the heating electrodes but also reduces the corrosion of the counter electrodes.

Abstract: Pairs of electrodes are symmetrically placed about the bend of a forehearth of a glass melting furnace. The electrodes are connected to the dual secondary windings of a step down transformer such that the firing paths of the electrodes cross each other in the molten material. The flow of the material across the firing paths coupled with the electrodes being connected to the dual secondaries of a common step-down transformer prevents hot spots and produces a balanced current flow across both firing paths.

Abstract: A glass melting furnace which uses Joule effect heating between electrodes, has a parallel attachment of electrodes to a single power source. The electrodes are arranged in rows of four electrodes across the width of the furnace. Multiple rows of electrodes spaced along the length of the furnace are used. The electrodes within a row are connected in a parallel format such that the current flow within a row can only be between two electrodes which are adjacent to each other. A current limiting controller and thermal currents within the molten glass balancing the temperature within the molten glass.

Abstract: A coaxial bus and bus system for electric furnaces which significantly reduces and minimizes heating and losses due to magnetic induction effects are characterized by a concentric tubular bus stem connected at one end to a transformer and branching at the other end to be connected to the furnace. The bus stem includes concentric tubular conductors which are connected at such one end to the transformer by respective diametrically opposed terminal lugs. At such other end, bus branches each including a conductive cross bar and a flexible feeder are respectively connected to the tubular conductors and form a yoke between which the furnace heating element or elements may be connected. The feeders are adjustably secured both pivotally to and longitudinally along their respective cross bars and each includes a plurality of stacked conductive leaves which are pressure welded together and to contact and reinforcing plates at their ends.

Abstract: A process for forming molten material in a melting furnace is disclosed. Bushings made of refractory or noble metal in the furnace are protected from cracking by applying a positive or anodic D.C. bias.

Abstract: An electric glass-melting furnace is disclosed having a first embodiment comprising: a chamber adapted for holding a body of molten glass, such for withdrawing molten glass therefrom, an arc electrode positioned in the body of molten glass; first and second electrodes positioned in the body of molten glass; a reactance means comprising a coil wound on a core, such coil having a first and second end and a center tap, the first end of the coil being connected to the first electrode and the second end of the coil being connected to the second electrode; and means for supplying electrical power to the arc electrode and the first and second electrodes, a first terminal of the power supplying means being connected to the arc electrode and a second terminal being connected to the center tap. The current flow through the first and second electrode is equalized by the coil. This embodiment may be modified to use a three phase power supply for powering three arc electrodes.

Abstract: A method and apparatus for determining the level of slag containing iron or iron compounds in the bottom of a glass melting furnace is disclosed. Electrically conductive electrodes or probes are placed in a predetermined position in the furnace. When the iron containing slag touches the electrodes or probes, the resistance between the electrodes or probes decreases or the current flowing between them increases activating a signal or alarm to warn the operator of the level of the slag in the furnace.

Abstract: An electric furnace for heating glass by the Joule effect comprising: a chamber adapted for holding a body of molten glass; a plurality of electrodes positioned in the chamber such that the electrodes form a zone with two clusters of electrodes in the zone, the clusters being located on opposite sides of the chamber, each of the clusters comprising first and second sets of electrodes, the first set being positioned closer to the other cluster than the second set and the first and second sets being positioned such that the second set of electrodes carries at least 60% of the current carried by the first set; and a source of power connected to the clusters.