SHAFT FURNACE Russian patent published in 1996 - IPC

FIELD: metallurgy, namely, equipment for process of calcining raw material or lumpy material, possibly, for firing lime and other materials in chemical and building industry branches. SUBSTANCE: shaft furnace includes vertical shaft with burners, recirculation gas duct, smoke suction unit, upper gas collector having openings along circle of shaft walls and connected by gas duct through apparatus for gas scrubbing with suction branch pipe of smoke suction unit, joined by pipeline with flue pipe. Lower gas collector is in the form of tube having opening for suction of combustion products from central portion of shaft to gas duct of upper gas collector before apparatus for gas scrubbing. Over tube of lower gas collector additional tube whose ends are connected with atmosphere and arranged in different levels is mounted. Horizontal shelf is secured to additional tube or tubes in central portion of shaft. Pressure branch pipe of smoke suction unit is connected with recirculation gas duct; upper gas collector and tube of lower gas collector are provided by throttles. EFFECT: improved design of shaft furnace. 2 cl