Abstract: The present invention relates to method and apparatus for preheating pulverous materials, such as glass batch constituents, prior to their introduction into a melting furnace to increase the efficiency and output of the melting installation. The pulverous materials are passed downwardly by gravity through a shell and tube preheater including an interior exhaust chamber to vent the contained moisture from the heated pulverous material. The venting prevents moisture condensation and build-up of the pulverous material within the tubes and batch materials, especially in cooler areas, which can cause tube pluggage. The subject invention is of particular utility to the glass industry and especially glass melting furnaces, but is also applicable to other types of furnaces.

Abstract: The present invention relates to method and apparatus for improving the preheating of pulverous materials, their introduction into melting furnaces, and their melting therein, with application to the recycling of some of the vitrifiable starting materials delivered to a tank furnace for glass making through a heat exchanger to raise its entry level temperature.

Abstract: The present invention relates to method and apparatus for preheating pulverous materials, such as glass batch constituents, prior to their introduction into a melting furnace to increase the efficiency and output of the melting installation. The pulverous materials are passed downwardly through a shell and tube preheater with super-atmospheric gas pressure over the pulverous material to force the contained moisture downwardly to be vented from a lower region of the preheater. The increased gas pressure prevents moisture condensation and build-up on the pulverous material within the tubes, especially in cooler areas, which can cause tube pluggage. The subject invention is of particular utility to the glass industry and especially glass melting furnaces, but is also applicable to other types of furnaces.

Abstract: The present invention relates to a method for preheating of pulverous materials in a tube heat exchanger prior to their introduction into a melting furnace, with particular application to the delivery by gravity of the vitrifiable starting materials through the heat exchanger to eliminate moisture therefrom prior to introduction of the essentially moisture-free materials into a tank furnace for glass making. The preheating serves to raise the entry-level temperature of the glass batch material and improve furnace fuel efficiency. The preheating involves recirculating at least part of the pulverous glass batch material through the open-ended tubes of the tubular heat exchanger to heat the same and remove moisture therefrom prior to initiating delivery of the glass batch material in preheated condition to the glass melting furnace. The present method is specifically directed at maintaining continuous operation of the preheater upon interruption of material flow through the preheater tubes for any reason.

Abstract: In the operation of a contact-type probe for sensing the level of glass in a tank or furnace, an arrangement is provided which will move the probe into contact with this molten glass at a relatively slow rate. After contact with the glass, the probe is quickly withdrawn from contact with the molten glass, the quick withdrawal being provided in the two embodiments. The first, by exhausting air from a diaphragm motor used to advance the probe and in the other embodiment electrically retracting the probe by the use of a solenoid.

Abstract: In accordance with the method and apparatus of this invention, glass-forming materials are subjected to heat and agitation sufficient to form a molten glass having mostly dissolved glass-forming materials, mostly completed chemical reactions between the glass-forming materials and containing a high number of gaseous inclusions, and containing up to 50 volume percent entrapped gases. This glass appears foamy. The molten glass is transferred to a second chamber to complete melting of any unmelted sand grains remaining from the glass-forming materials, and completes the chemical reactions that remain incompleted, and to remove any remaining cords, and to reduce the foamy character of the melt to a dense molten glass which contains only small-sized gaseous inclusions.