Process and apparatus for the recovery of heat from furnaces for working glass and similar products

Claim 1

THE PROCESS OF RECOVERING HEAT FROM A SHAFT FURNACE FORMED OF A TUBULAR WLL COMPOSED THROUGHOUT ITS EXTENT OF REFRACTORY MATERIAL AND PROVIDED AT ITS LOWER END WITH A MELTING CHAMBER AND AT ITS UPPER END WITH OPENINGS THROUGH WHICH RAW MATERIALS ARE FED INTO THE SHAFT AND FUMES ARE REMOVED FROM THE SHAFT, THE RAW MATERIALS BEING PREHEATED AS THEY FALL FREELY DOWN THROUGH THE SHAFT TO THE MELTING CHAMBER BY THE FUMES WHICH RISE FROM THE BATH OF MOLTEN MATERIAL IN THE MELTING CHAMBER AND PASS UP THROUGH THE SHAFT IN COUNTERCURRENT RELATION TO THE FREELY FALLING RAW MATERIALS, COMPRISING CIRCULATING COOLING FLUID OVER THE ENTIRE AREA OF SAID TUBULAR WALL BETWEEN A FIRST LEVEL SITUATED SLIGHTLY ABOVE THE PLANE OF THE LEVEL OF THE BATH OF MOLTEN MATERIAL AT THE LOWER END OF THE SHAFT, AND A SECOND LEVEL AT WHICH THE FUMES ARE REMOVED FROM THE SHAFT THROUGH ONE OF SAID OPENINGS, THE COOLING FLUID BEING CIRCULATED IN SEPARATE STREAMS OVER THE EXTERIOR SURFACE OF SAID TUBULAR WALL THROUGHOUT THE ENTIRE AREA OF THE MAJOR PORTION OF THE HEIGHT OF THE TUBULAR REFRACTORY WALL ABOVE THE ELVEL OF THE BATH AND EXTENDING BETWEEN SAID FIRST LEVEL AND A THIRD LEVEL SHORT OF SAID SECOND LEVEL AND SO THAT SUCH STREAMS OF COOLING FLUID ARE IN INTIMATE HEAT EXCHANGE RELATION WITH THE REFRACTORY MATERIAL IN SUCH EXTERIOR SURFACE AREA OF SAID WALL, AND THE COOLING FLUID BEING CIRCULATED IN SEPARATE STREAMS OVER THE INTERIOR SURFACE OF THE REFRACTORY MATERIAL OF SAID TUBULAR WALL THROUGHOUT THE ENTIRE AREA OF SUCH INTERIOR SURFACE THEREOF BETWEEN SAID THIRD AND SECOND LEVELS, THE COOLING FLUID HEATED ONTHE INTERIOR OF SID TUBULAR WALL BEING JOINED WITH THE COOLING FLUID CIRCULATING ONTHE EXTERIOR OF SAID TUBULAR WALL AT THE UPPER END OF SID EXTERIOR SURFACE AREA OF SAID WALL.