METHOD OF BURNING SOLID FUEL AND FURNACE FOR ITS REALIZATION Russian patent published in 1995 - IPC

FIELD: power engineering. SUBSTANCE: in feeding fuel and sorbent to fluidized bed which consists of central and peripheral zones brought in communication and formed by at least two central and peripheral air flows, speed of first flow is selected depending on the conditions of spouting and speed of second one is selected depending on the conditions of quasi-liquefaction, as well as on the conditions of introducing at least two flows of secondary air; heat removal zone is organized at the boundary of central and peripheral zones of fluidized bed which brings central and peripheral zones in communication; fuel is introduced in central zone of fluidized bed and is burnt in gasification mode; central flow of primary air is divided into two parts which are introduced into respective zone by crossing jets forming swirled spouting flow of fluidized bed with lowering section over its periphery. Afterburning is effected in at least two flows of secondary air introduced by opposite shifted jets above peripheral zone forming at least one horizontal vortex. Particles of fuel separated from it are returned in adjustable manner to central zone taking heat from heat removal zone through supply of peripheral air flow directed towards heat removal zone. Fluidized bed furnace is provided with additional screens built in its housing shielded with tubes. Additional screens are made of tubes with whose help combustible chamber is separated from afterburner chamber. EFFECT: enhanced reliability. 10 cl, 8 dwg