FIELD: circulating-fluid-bed combustion plants. SUBSTANCE: plant has furnace whose lower part accommodates grate 10 for producing fluidized bed, at least one hard-particle separator incorporating device for cleaning stack gases from solid materials, so-called return channel 6a for conveying solid material back to fluidized bed communicating with gas flap that functions to prevent gas flow ingress under certain conditions from grate towards solid- particle separator. Gas flap K1 has closed bottom 14 or counterpart with cover 11 or counterpart above it provided with holes or counterparts, compartment 13 or counterparts, vertical wall of return channel 6a with holes 15a between bottom 14 and cover 11 and abutting the compartment. Solid material is conveyed through channel 6a, holes in cover 11 to compartment 13 wherefrom it is passed to fluidized bed on grate 10 through holes 15a in wall of return channel 6a. EFFECT: improved design. 14 cl, 4 dwg
