GLASS MELTING FURNACES

摘要

A method is disclosed of melting glass in a melting furnace in which a pool of molten glass is confined above a furnace bottom wall and a layer of unmelted particulate glass batch is deposited on the surface of the pool. Heating electrodes are immersed in the pool of molten glass and located at a vertically medial portion of said pool. The method includes heating the pool of molten glass by the electrodes to form an isothermal layer of molten glass, circulating heated molten glass upwardly from the electrode location to melt the batch layer, and returning most of the glass back to the electrode location for reheating while flowing a portion of the glass downwardly beyond the electrode location. Glass located beneath the electrodes flows downwardly in the pool and through a vertical outlet passage directly into a forming apparatus underlying the pool as glass is withdrawn through said forming apparatus. A heat exchange medium is passed through a heat exchanger located above the forming apparatus in heat exchange relation (a) with the furnace bottom wall and (b) with the downwardly flowing glass in the outlet passage in a manner to cool the molten glass in successive, essentially isothermal layers. As a result, the glass issuing from the passage is at a substantially uniform temperature which is conducive to forming in the forming apparatus.