GB401392A - Cement manufacture - Google Patents

Abstract

401,392. Rotary cement kilns. LEE, H. S., 2842, West Grand Boulevard, Detroit, Michigan, U.S.A. June 4, 1932, No. 15868. Convention date, June 10, 1931. [Class 51 (ii).] The clinker produced in a rotary cement kiln 10 is discharged into a closed chamber 21 in which it is subjected to the action of air supplied through inlets 28 by a fan 29, Fig. 3, pivoted flaps 74, 78 being provided to prevent passage of air to the kiln 10 through the shoot 12 and escape of air through the discharge end of the chamber. The clinker discharged at the lower end of the shoot 12 first fills a pan 18 to form a bed from which the clinker subsequently discharged is carried into the chamber 21, and along the grate 22 provided therein, by a scraper conveyer 16. The fines falling through the grate 22 are received in hoppers 32 fitted with rotary discharge valves 34. The chamber 21 is divided into two compartments, serving for completion of the burning and for cooling, respectively, by an air-cooled pivotally mounted partition 42 which carries counterweights 62 and is so arranged that its trunnions 50 may be adjusted longitudinally in the sealed slots 46 to vary the relative capacities of the two compartments. The latter have separate off takes 64, 66 for the heated air, the former serving to supply secondary combustion air to the kiln 10, while the latter leads to a waste heat boiler or other heat-exchange apparatus. As shown in Fig. 3, the kiln is fired by a burner 67 supplied with pulverized fuel and primary air through conduits 70, 72 respectively, the damper-controlled hot-air pipe 64 supplying secondary air to a chamber 68 surrounding the burner tube 67. The latter is telescopically mounted on the air conduit 72 so that its position within the chamber 68 may be adjusted by a rack-and-pinion device 88, 90. Mounted in the conduit 64 is a funnel-like dust collector 84 which delivers the collected dust into an offset chamber having a gravityoperated discharge door 86.