FIELD: methods of cooling recirculating materials in combustion chamber of boiler with air- fluidized bed. SUBSTANCE: fuel A is introduced in lower portion of combustion chamber with circulating powder-like material of boiler with air-fluidized bed and inert circulating material which contains portion of unburnt powder-like fuel A circulates from upper portion of combustion chamber to its lower portion together with powder-like material. Fuel gases flow from powder-like material separator 13 directly to boiler via pipe line 15 with gas outlet 16; thermal energy of fuel gases is then transmitted for other purposes through heat exchanger 16a. Part of cooled fuel gases recirculates via pipe line 20 together with circulating material. Cooling capacity of boiler may be regulated by means of cooled fuel gases through acting on temperature of circulating material. EFFECT: enhanced efficiency. 11 cl, 6 dwg
