| 摘要 |
PURPOSE:To roast and regenerate used molding sand on which a combustible binder sticks with high thermal efficiency in the stage of roasting and regenerating the molding sand in a fluidized bed by heating the air for forming the fluidized layer by the heat retained in the high-temp. regenerated sand after roasting. CONSTITUTION:A combustible binder used in the stage of molding a casting mold is stuck to molding sand knocked out after use for casting and therefore such sand is supplied through a charge port 5 of a fluidized roasting furnace 1 onto the guide plate 2a of a preheating part 2. Air is blasted at the same time from a blower 9 to the furnace to form the fluidized bed 11 of the preheated molding sand a' in the lower part of a combustion part 3 and a burner 6 is ignited to heat and roast the sand a' forming the bed 11 thereby burning away the binder sticking to the sand and regenerating the sand. The sand a'' which is heated to a high temp. as a result of the regeneration by roasting heats the air in a heat exchanger 10 while descending in a flowing air heating part 4. The sand itself is cooled and is recovered as regenerated sand through a take- out port 7. The air heated to a high temp. in the heat exchanger 10 is released from flowing air nozzles 8 into the bed 11 and is thus utilized for heating-up the bed 11. |
