Standard Article

7 Modeling Moving and Fixed Bed Combustion

Part 4. Solid Fuels

  1. Bernhard Peters,
  2. Harald Raupenstrauch

Published Online: 15 JUL 2010

DOI: 10.1002/9783527628148.hoc061

Handbook of Combustion

Handbook of Combustion

How to Cite

Peters, B. and Raupenstrauch, H. 2010. Modeling Moving and Fixed Bed Combustion. Handbook of Combustion. 4:7:257–283.

Author Information

  1. University of Luxembourg, Faculty of Sciences, Luxembourg-Kirchberg, Luxembourg

Publication History

  1. Published Online: 15 JUL 2010

Abstract

Owing to declining sources of primary energy and a demand for sustainability, solid fuels and their use for generation of energy have gained a growing attraction during recent years. In particular, biomass is considered as an alternative source because it contributes to reduced net emissions of carbon dioxide. To understand the conversion behavior of solid fuels, both experimental and theoretical investigations were initiated. This chapter deals with the modeling aspect of solid fuel combustion in fixed and moving beds. The conversion of both a fixed and moving bed is a rather complex process involving various thermodynamic, fluid dynamic, physical, and chemical aspects and their interactions. Thus, the relevance of each aspect will be described within this chapter and moreover their dependence on each other. Major processes during solid fuel combustion include, in general, heating, drying, pyrolysis, devolatilization, gasification and perhaps combustion. These processes of thermal conversion involve chemical reaction processes that consume or generate energy. In moving beds, the redistribution of the solid fuel particles has to be taken into account additionally. All these aspects may be represented by models of different levels of accuracy, whereby the models may be divided into the continuum mechanics and the discrete approach. The first approach treats solid fuel as a continuum for which characteristics such as size or shape disappear due to the averaging process. However, the discrete approach takes all these characteristics into account on a particle level, and therefore, offers a priori a higher degree of accuracy.

Keywords:

  • biomass;
  • fixed bed combustion;
  • modeling;
  • moving bed combustion;
  • solid fuel combustion;
  • thermal conversion