Devolatilization, biomass combustion

Saastamoinen J.J., Model for Drying, Devolatilization, and Combustion of Small Biomass Particles in Entrained Flow, Iso-thermal Furnaces , project 4450063-4/443-3/30, version 5, Domestic Fuel Laboratory, Jyvaskyla, Finland, (1985)... 

Volatiles composition is an important factor influencing the conversion of volatile nitrogen to NO and N O. The high CO content in biomass volatiles seems also to be partly responsible for the low levels of NjO emissions in biomass combustion. As the effect of most parameters is contrary a simultaneous reduction of NO and N O by primary measures is difficult, especially as other emission limits (e.g. for CO) have also to be captured. However, affecting devolatilization conditions to favor NH3 to HCN release and minimizing air-to-fuel ratio seems promising. 

As a particle is heated, it dries and devolatilizes. Water vapour and combustible gases are produced and transported to the surface of the particle and out into the gas between the particles, where the gases ignite if the conditions are suitable. Devolatilization of biomass starts already at temperatures about lOCC and spontaneous ignition of... 

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