Numerical Simulation Of Combustion Of Biomass Briquettes In A Rotary Kiln

Biomass energy is a clean and efficient energy. To a large extent, the environmental problem can be solved if non-renewable energy resources like Oil, gas and coal are replaced by Biomass energy. China is a agricultural country with a large population, and the distribution of biomass energy in China is extremely broad. In particular, biomass is the main resource used in daily life, in the vast rural areas. With the development of briquetting technology and combustion technology, biomass briquette will be widely used as a fuel in industrial furnaces.With the increase of the boiler operating conditions and requirements of environmental protection, the numerical simulation will become more and more important. A lot of research on simulation of combustion of coal in a rotary kiln are underway currently, and a set of mathematical methods of combustion simulation are obtained. However, theoretical and applied research on combustion of biomass fuel is very few in our country, and there is no report in biomass briquettes to replace coal as a fuel in kilns. Therefore, it is necessary to carry out the research in this area.Briquetting technology is the most effective in a new application of biomass energy, and the prospects are very broad, which Meets national energy policy and environmental policy. The paper first introduces the chemical composition of biomass, the principle and process types of biomass briquetting, the development of briquetting devices. It also analyzes on the characteristics of biomass briquettes and its combustion, combustion process and ignition performance.The paper researches the experimental model of the rotary kiln for biomass briquettes and simulates combustion of biomass briquettes in a rotary kiln using CFD software FLUENT. Mixture-Fraction/PDF model was used to simulate turbulent combustion; P-1 radiation model was used for simulating radiation heat transfer; the Langrange/Euler's method was used for dealing with momentum, mass and energy exchange between the solid and the gas phase; the two-competing rates model for devolatilization and the kinitics/diffusion limited combustion model for simulating surface combustion of biomass pellets. At different operating parameters, the optimal operational parameters are put forward as the temperature fields are compared. In order to achieve the target of energy-saving and environmental protection, the research will lay the foundation for the study of combustion of biomass briquettes in a rotary kiln, which replaces the coal...