Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
Numerical study of a rotary kiln. A case study of an industrial plant in Paraguay.
Submission Author:
Hugo González , Central , Paraguay
Co-Authors:
Cristhian Manuel Zarate Evers, DARIO ALVISO, Juan Carlos Rolon
Presenter: Cristhian Manuel Zarate Evers
doi://10.26678/ABCM.ENCIT2016.CIT2016-0239
Abstract
Rotary kilns are heat exchangers in which thermal energy from a hot gas is transferred to the bed material. During its passage along the kiln, the bed material will have various heat exchange processes, a sequence for long rotary kilns being drying, heating, and chemical reactions that cover a wide range of temperatures. Most kilns allow direct contact between the freeboard gas and bed material in a common counter current flow configuration. Rotary kilns in Paraguay are used in the cement industry, i.e. to convert raw meal into cement clinker by heating the raw material mixture to a temperature of approximately 1450 ºC. This process demands a great amount of energy, around 3 GJ/ton of clinker, provided by fuel oil burners. This paper presents the numerical study of the cement rotary kiln of Industria Nacional de Cemento (INC), the main manufacturer of Portland cement in Paraguay. The exact analytical solution for the bed depth profile of solids in a rotary kiln obtained by Danish et al (2012), in combination with the Saeman (1951), model are used to find the bed depth profile, the axial velocity profile, mean residence time of the material in the kiln. Furthermore, a one-dimensional model, developed by Mujumdar and Ranade (2006), is used in this study to simulate key processes occurring in solid bed and to determine operating parameters, taking into account the chemical reactions occurring during clinker formation and heat transfer in rotary kilns. The numerical results are analysed in order to optimize the kiln operation and reduce fuel consumption.
Keywords
Rotary kilns, Portland Cement, Industrial Plant
