GB616840A - Method of and apparatus for burning finely divided or pulverized fuel at very high rates of heat liberation - Google Patents

Abstract

616,840. Pulverulent-fuel furnaces. INTERNATIONAL COMBUSTION, Ltd. July 9, 1946, No. 20475. Convention date, Aug. 21, 1945. [Class 51 (i)] In a pulverulent-fuel furnace comprising a primary combustion chamber A communicating through a restricted outlet B with a secondary combustion chamber C leading to a flue D, the fuel-air mixture is admitted downwardly at high velocity, e.g. 6,000 - 24,000 ft. per minute, through a nozzle 10, and secondary air is admitted at high velocity through an annular inlet 12 containing a ring of pivoted vanes 131 so as to impart a swirling motion to the mixture, which ignites on entry. Further air is admitted at high velocity, e.g. 12,000-60,000 ft. per minute, through four circumferentially spaced inlets 16 to drive unburnt fuel inwardly, these inlets being inclined at an angle to the radius (see Fig. 3, not shown) so as to maintain the swirling motion. Similar inlets 161, 1611 are provided at lower levels so that unburnt fuel is repeatedly driven inwardly. The restriction of the outlet B enables a super-atmospheric pressure, e.g. 2 - 110 inches of water, to be maintained in the chamber A. The furnace temperature is maintained above the fusion point of the ash so that molten slag is flung outwardly on to the chamber wall and adheres thereto. This slag drips off the wall into the base of the chamber C from which it is removed through a door 17. Any solid combustible particles adhering to the slag are burnt at the chamber wall. The walls of the chamber A are lined with water tubes 7 separated by refractory material, the chamber C is lined with water tubes 9, and steamgenerating coils and superheater tubes (not shown) are located in the flue D. The Specification as open to inspection under Sect. 91 also describes a construction, Fig. 4 (cancelled, not shown) in which the fuel-air mixture is admitted tangentially. This subject-matter does not appear in the Specification as accepted.