Numerical investigation of bed depth height, axial velocity and mean residence time of inert particles in steady state industrial cement rotary kiln: Case of Figuil Plant in Cameroon

Abstract

In order to simulate the structure of granular materials in a rotary kiln under the steady-state regime, mathematical models have been developed by different authors. Experimental data are used to test the equations predicting the bed depth profile, the axial velocity profile and the mean residence time of granular particles in the kiln. The Ghirelli and Leckner (2004) [1] formulation is used for the first time to evaluate the residence time. Comparisons show that this formulation gives a satisfactory shape although it underestimates the mean residence time. For bed depth and axial velocity profiles, the Saeman (1951) [5] mechanistic model which has good agreement with experimental data found in literature, is used to predict these characteristics in the Figuil industrial cement kiln. The Lee and Shun (1999) [22] phenomenological relation which gives good agreement with experimental data is used for the prediction of mean residence time.