Float glass furnaces use a unique glass-manufacturing method that enables perfectly flat glass to be formed by floating the molten glass on molten tin. These types of furnaces are the largest of all types of glass melters. In order to reduce the amount of energy required to melt the glass, these furnaces have regenerators that utilize checker brick to improve efficiencies by taking advantage of the excellent heat exchange properties inherent in ceramic materials. As the furnace exhausts through the checker packing, the bricks are preheated by the waste gases, providing a source of energy to preheat the combustion air when the cycle is reversed. Regenerator efficiencies can be affected by a variety of factors, from pack design to regenerator size. The materials utilized by the regenerators must be able to withstand many different forms of attack, such as corrosion by alkalis, silica, and sulfates, as well as thermal shock and creep. The selection of refractories is critical to the operation and life cycle of the regenerator. Combinations of the NARMAG^® family of products, NIKE family of products, and KALA^® provide the best-performing regenerator. In the melter construction, the paving consists of AZS materials like VISION^® and zircon ram like TZ^® 717-W RAM MIX, with a clay flux backup material like CRYLA^® XXL. Since the sidewalls and breast walls most commonly consist of fused-cast AZS and the crown of silica, zircon is required as a buffer between the possible reaction of the AZS and the silica. TZB^® is the industry’s benchmark brand for zircon brick.

Industry brochure: Refractory Solutions for Glass