Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
EXPERIMENTAL AND NUMERICAL INVESTIGATION OF COAL DEVOLATILIZATION IN A DTF
Submission Author:
Daniela Mortari , RS
Co-Authors:
Daniela Mortari, Carlos Henrique Lauermann, Juliana Pohlmann, Thamy Cristina Hayashi, Fernando Pereira
Presenter: Daniela Mortari
doi://10.26678/ABCM.ENCIT2018.CIT18-0678
Abstract
This study investigates experimentally and numerically the devolatilization process of a low-rank Brazilian coal. Coal devolatilization is the first and faster reaction during the convencional air combustion. With the purpose of reducing the reaction velocity, the experiments will be investigated at different temperatures, varying from 600 to1100°C and different residence times, varying from 160 ms to 315 ms under N2 atmosphere. The physicochemical characterization of the coal was performed by means of high heating values, activation energy determination, ultimate and proximate analysis. Preliminary DTF experiments have been carried out within the investigation of the coal combustion evolution and the results confirmed that the burnout increases as the residence time increases. However, the different temperatures and the devolatilization step have not been exploited. The goal of this study is to obtain a devolatilization response surface, scanning the completely accessible reactive area in the DTF. In parallel, a model of devolatilization and combustion of solid fuels in the DTF has been developed. The model includes the energy, momentum and mass balances, and allows for the prediction of burnout as well as the residence time and particle size variation within the DTF. It has been associated in a routine developed for the estimation of the kinetic parameters of the reaction steps of mixtures of particles of variable granulometry of single fuel. This work is in an early stage of development. Therefore, the main conclusions will be obtained in the next stages of the research.
Keywords
devolatilization, surface response, Coal, DTF, kinetic
