GB1169744A - Improvements in the Thermal Treatment of Briquettes - Google Patents

Abstract

1,169,744. Heating or cooling articles in fluidized beds. COAL INDUSTRIES (PATENTS) Ltd. 31 Jan., 1967 [4 Feb., 1966], No. 5021/66. Heading F4U. Articles to be heated or cooled are passed through a bed of fluidized particulate material, the latter material remaining in the bed throughout the heating or cooling process. As shown, briquettes 15 are fed into a trough 3, containing a bed of fluidized sand, through an inlet 8 and are removed from the opposite end of the trough by an elevator 11. The latter comprises a plurality of buckets which are perforated to prevent removal of sand. The bottom of the trough is perforated and the fluidizing gas, e.g. air, flue gas or steam is supplied via a plurality of inlet chambers 5. A thermostatic device 13 is associated with each chamber and may be used to control the quantity of a liquid coolant, e.g. water, which may be supplied to the bed. The fluidizing gas may be heated or cooled and may be supplied in pulses. Alternatively the bed may be heated by partial combustion of the briquettes in the bed. The embodiment of Fig. 2 (not shown), comprises a central longitudinal chamber flanked by side chambers, the chambers being separated by perforated partitions which allow the sand but not the briquettes to pass between the chambers. The briquettes pass through the central chamber and the sand is heated or cooled in the side chambers. Circulation of the sand may be caused by supplying fluidizing gas to the side chambers at a greater or lower pressure than that supplied to the central chamber.