FIRE-TUBE BOILER Russian patent published in 1997 - IPC

FIELD: fire-tube boilers working on powdered ash-bearing fuels. SUBSTANCE: fire-tube boiler has inlet holes 15 of fire tubes 9 widening in form of hearth in wall 16 which separates boiler drum from swivel chamber 4. Fire tube 2 has such sizes that guaranteed cooling of flue gases at fire tube outlet below softening point of ash of respective fuel is ensured taking into account power of boiler. Number of fire tubes 9 and their inner diameter 2R provide for velocity head not below 40 Pa. Blow-off tube 13 mounted on swivel chamber 4 is used for approximately tangential blowing through separating wall to avoid ash deposition on inlet holes. EFFECT: enhanced efficiency. 10 cl, 5 dwg