Direct contact raining bed counterflow cullet preheater and method for using

摘要

An improved method and apparatus for preheating cullet used as feedstock for a glass furnace. A direct contact raining bed is described through which cullet is fed by gravity flow, with furnace flue gases as combustion products of a separately-fired heater passed in counterflow to heat the cullet by direct contact. The preheater includes deflectors to retard passage and increase the path length of cullet flowing through the raining bed, and the deflector plates are mounted at specific declination angles and have their geometric parameters selected to optimize cullet residence time. Glass furnace systems are described which include the raining bed cullet preheater in series and parallel flow relationships with a glass batch preheater.