The new type swirl-spray precalciner used in the cement plant is a large-scale and complex reactor in chemical engineering. In this article, a full three-dimensional numerical simulation technique is carried out for the swirl-spray precalciner. A new method for treating the particle-wall boundary condition in rectangular-structural grid is deducted to avoid the endless loop movement of particle in dead angles of grids and a four-mixture-fraction model is developed to describe the multi-components mutual transportation in the precalciner. The results of simulation disclose and predict the physical-chemical processes of the swirl-spray precalciner and the model results, especially the average raw material decomposition ratio, coal bum-out ratio and the temperature of exits, are agreed well with the measured results. (c) 2005 Elsevier B.V. All rights reserved.