GB212298A - Process and apparatus for the utilization of the combustion gases from rotary cement burning kilns - Google Patents

Abstract

212,298. Jorgensen, M. Vogel-, Ronne, E., and Middleboe, K. Dec. 4, 1922. Rotary kilns; waste gases, utilizing. - In a rotary cement kiln to which the raw material are fed in a wet state, a part of either the hot gases or of the raw materials is kept separate from the remainder in the drying and preliminary-heating zone so that a part or the whole of the hot gases will leave the kiln in a better state for subsequent utilization, for example in steam-generating plant. In the apparatus shown in Fig. 1 the drying-zone of the kiln is subdivided into a central flue 2 leading to a dust chamber 4, steam generator 8, economizer 9, and exhaust fan 10, and four outer chambers 5 leading in the ordinary manner to the stack flue 12. The raw materials are supplied through the chambers 5 only, and thus the hot gases which pass to the steam generator are kept free from moisture. The chambers 5 are preferably spaced from one another and from the flue 2 by passages to which the air has access. The flue 2 may be stationary instead of being formed to rotate with the kiln, and the. heating value of the separated gases may be increased by mixing fuel therewith. In the plant shown in Fig. 4 a portion of the wet material to be burnt is fed to the kiln 1 at its inlet end through the duct 13<1>, while the remainder in a dry state is fed in at the end of the drying-zone through the stationary chamber 21. The hot gases leaving the kiln are utilized first in the steam-generating plant 8 and then for drying the second portion of the raw materials in the drum 17.