GB1436160A - Rotary ore-reducing kilns - Google Patents

Abstract

1436160 Supplying gases to rotary kilns ALLIS-CHALMERS CORP 30 Oct 1973 [31 Oct 1972] 50358/73 Heading F4B In a rotary arc reducing kiln 6 with an internal burner 11, fluid fuel and air from conduits 14 and 16 are distributed to nozzles 12 spaced along said kiln by fluid distribution apparatus 17 including a three-way valve 18 and trip mechanism so arranged that fuel and air may be supplied to each nozzle 12 alternately or air alone may be supplied. Each valve spindle 27 carries a cam plate 37 with cams 39, 41, 42 and 43, the cam 39 being on the opposite side of the plate to the other cams. As the kiln rotates the cams are actuated in turn to index the plate 37 by trip devices 29, 31, 32 and 33, the latter actuating the cam 39 and being retractable by an hydraulic servomotor 34 and valve V. Trip devices 29, 31 and 32 operate each valve 18 to a " fuel-on ", " fuel-off " and " air-on " position and device 33 operates the valve to an " air-off " position. On lighting up the kiln, trip device 32 leaves each valve in an " air-on " position and device 33 is retracted preserving this position. When the kiln is fully heated a relay R is deenergized operating valve V and servomotor 34 to restore trip device 33 to its operative position. The kiln is then charged and with all the trip devices fully operative fuel is supplied into the charge material as each nozzle 12 passes below it and air is discharged through each nozzle in the upper position until it reaches the trip device 33.