Modeling of coal combustion in the CFB by the EDC model with the global reaction mechanism

• Published in: International journal of numerical methods for heat & fluid flow Vol. 28; no. 4; pp. 963 - 981
• Main Authors: Kang, Zhizhong, Ding, Shixing, Shuai, Zhi-ang, Sun, Baomin
• Format: Journal Article
• Language: English
• Published: Bradford Emerald Publishing Limited 03.04.2018; Emerald Group Publishing Limited
• Subjects: Ammonia; Carbon; Carbon dioxide; Chemical reactions; Chemistry; Coal; Combustion; Computer simulation; Energy conservation; Fluid dynamics; Fluid mechanics; Fluidized beds; Gases; Heat; Modelling; Nitrogen compounds; Nitrous oxide; Oxidation; Pollutants; Radiation; Reaction mechanisms; Spontaneous combustion; Circulating fluidized bed; Eddy dissipation concept; Combustion; Multi-fluid Eulerian
• ISSN: 0961-5539; 1758-6585
• DOI: 10.1108/HFF-11-2016-0467

Purpose This paper aims to shows the ability of the EDC model with a global reaction mechanism to describe reactions in the Eulerian simulation of a circulating fluidized bed (CFB). Design/methodology/approach The eddy dissipation concept (EDC) model is embedded in an Eulerian-Eulerian approach to simulate homogeneous reactions. Findings EDC_G is better than ED_FR in describing chemical reactions. The reaction of CH4 with O2 is faster than that of CO with O2, and NH3 is more liable to be converted than HCN. The combustion rate is higher than the Boudouard reaction rate of coal particles.N2O is mainly reduced by carbon, and NO is mainly converted by carbon into N2 and CO2. Originality/value The EDC model with a global reaction mechanism is embedded in a multi-fluid Eulerian approach to simulate the homogeneous reactions in the coal combustion in a CFB, including combustion of volatile gases, desulfurizing reactions and NOx reactions.