A Mathematical Model of Biomass Briquette Fuel Combustion

Jingxia Sui, Xiang Xu, Bo Zhang, Changjiang Huang, Jinsheng Lv

School of Energy and Power, Dalian university of technology, Dalian, China.
School of Energy and Power, Dalian university of technology, Dalian, China; Wen Zhou Special Equipment Inspection Center, Wenzhou, China.
Wen Zhou Special Equipment Inspection Center, Wenzhou, China.

DOI: 10.4236/epe.2013.54B001                

Abstract

The numerical simulation model is proposed according to the characteristics of the biomass briquette fuels, which involves two main areas of interest: the solid combustion model in the bed and the out-of-bed gas combustion model. The contents and characteristics of 3 kinds of biomass and coals were experimentally tested. The biomass fuels compared with the coal fuel have the following characteristics: 1) Higher volatile content, lower fixed carbon content and calorific value; 2) Lower carbon content, higher oxygen content; 3) Lower ignition temperature, faster burning velocity. The discredited equations were established by the finite element analysis method, which analyzed the fuel endothermic process on the grate, while the out-of-bed gas combustion process was simulated by CFD. These two processes are strongly coupled. The results of the numerical simulation contain the steady state temperature distribution, oxygen distribution, carbon dioxide distribution and so on, which are used to judge burning effect and provide the correct furnace transformation method.

Keywords

Biomass; CFD; Simulation; Boiler; Combustion

Conflicts of Interest

The authors declare no conflicts of interest.

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