摘要 |
<p>A glassmelting method wherein fuel and oxidant combust in a combustion zone in the upper level of a furnace and shield oxygen is passed over the molten glass surface at a low velocity to form a shield layer between the combustion zone and the molten glass, to counteract the reaction of water vapor, resulting from the combustion, with species within the molten glass, to reduce volatilization of alkali species from the molten glass, and to make the molten glass more oxidizing. Reducing gas may be used in place of shield oxygen to make the molten glass more reducing. Both shield oxygen and reducing gas may be used sequentially in a multi-zone furnace.</p> |