FIELD: method and device for circulation of solid substances in reactor with fluidized bed. SUBSTANCE: reactor chamber 12 with a liquid cushion has an internal circulation of particles. Coarse recirculating particles are not allowed to heat-transfer areas 40 by classification of particles close to bottom 24 of reactor chamber 12 with the aid of the chamber for particles (22), having hollow wall 30 with holes or slots with a maximum dimension of at least 30 mm. Heat-transfer areas 40 may be positioned in the chamber for particles (22). Coarse particles sink along the walls of the chamber for particles in the reactor chamber, and part of fine particles in the chamber for particles preferably recirculates back to the liquid cushion. The hollow wall preferably serves as the upper wall of the chamber for particles and may have a refractory coating with recesses and/or may be made of water-supply pipes connected through ribs to the holes or slots in the ribs. EFFECT: enhanced heat extraction. 25 cl, 7 dwg
