In a calciner for cement production, limestone (CaCO3) particles are decomposed into quicklime (CaO) and carbon dioxide (CO2) during the calcination process. The complex flow and temperature distribution caused by fuel combustion and calcination reaction of limestone are essential to calciner performance. This paper presents a method by coupling the calcination model and combustion into multiphase flow simulation. In this approach, flue gases, CaCO3, and CaO particles are defined asmultiple continuous phases, and heavy oil droplets are defined as discrete phase. This simulation is based on the Euler multiphase model for continuous phase and discrete phase model for the oil phase. The transport of heat, mass, momentum, species and energy among these different phases are calculated by solving the governing equations of each phase with phase-interacting coefficients and models. To verify the accuracy of this modeling approach, numerical predictions were compared with measurement data collected from cement production lines, which yielded satisfactory results. This modeling approach can help optimize calciner design, performance, and process parameters in actual industrial applications. (c) 2020 Elsevier B.V. All rights reserved.