Reduction of nickel sulfide stones in a glass melting operation
AssigneePPG Industries, Inc.
InventorsGeorge A. Pecoraro, Amarendra Mishra, Larry J. Shelestak, James V. Jones
Life of this patent
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Abstract
Material selected from the group consisting essentially of molybdenum, arsenic, antimony, bismuth, copper, silver, potassium dichromate and iron chromite, is added during the manufacture of soda-lime-silica float glass to reduce the occurrences of nickel sulfide stone defects. Material is added in sufficient amounts such that the resulting glass is at least 0.010 wt. % selected material. In a preferred embodiment of the invention, molybdenum is added in the form of sodium molybdate such that the resulting glass is at least 0.015 wt. % molybdenum.
Claims16
In a method of manufacturing soda-lime-silica float glass, including the steps of melting and refining raw batch materials to form molten glass, wherein nickel in said molten glass added as a component of said batch materials or as an impurity in said batch materials, forms nickel sulfide stone defects which degrade the quality of said glass, the improvement comprising the step of:
- reducing the formation of nickel sulfide stones by adding to said batch materials, molybdenum in an amount such that said batch materials are 0.01-0.09 wt. % molybdenum.
In a method of manufacturing soda-lime-silica float glass, including the steps of melting and refining raw batch materials to form molten glass, wherein nickel in said molten glass added as a component of said batch materials or as an impurity in said batch materials, forms nickel sulfides stone defects which degrade the quality of said glass, the improvement comprising the step of:
- reducing the formation of nickel sulfide stones by adding to said batch materials, molybdenum in an amount such that said soda-lime-silica glass is 0.01-0.075 wt. % molybdenum.
In a method of manufacturing soda-lime-silica float glass, including the steps of melting and refining raw batch materials to form molten glass, wherein nickel in said molten glass added as a component of said batch materials or as an impurity in said batch materials, forms nickel sulfides stone defects which degrade the quality of said glass, the improvement comprising the step of:
- reducing the formation of said nickel sulfide stones by adding to said batch materials, stone reducing material selected from the group consisting essentially of molybdenum, bismuth, copper, silver, potassium dichromate and iron chromite and combinations thereof, in an amount such that said batch materials are 0.01-0.25 wt. % stone reducing material.
In a method of manufacturing soda-lime-silica float glass, including the steps of melting and refining raw batch materials to form molten glass, wherein nickel in said molten glass added as a component of said batch materials or as an impurity in said batch materials, forms nickel sulfide stone defects which degrade the quality of said glass, the improvement comprising the step of:
- reducing the formation of nickel sulfide stones by adding to said batch materials, stone reducing material selected from the group consisting essentially of molybdenum, antimony, bismuth, copper, silver, potassium dichromate and iron chromite and combinations thereof, in an amount such that said soda-lime-silica glass is 0.01-0.22 wt. % stone reducing material.
Dependencies are inferred from the claim text.