Numerical calculations of limestone calcination in cement industry with use of shrink core model

Abstract

Clinker burning is the most complex process in cement production from limestone. These are especially visible for the two-stage combustion of fuel in a rotary kiln without the typical reactor-decarbonizator. This work presents the results of numerical studies on thermal-flow phenomena in the riser chamber, which will be designed to burn fuel in the system AS (combustion air supplied separately from the clinker cooler). The mathematical model is based on a combination of two methods of motion description - Euler method for the gas phase and Lagrange method for particles [1]. The most important part of the calculation methodology is the modeling of the calcination process, which depends on the gas temperature, CO2 partial pressure and material roasting time. The obtained results of calculations can be the basis for further of optimization the design and operating conditions in the riser chamber with the implementation of the system AS.