Biomass is a collective term for plant or animal material used to produce electricity or heat for direct use through combustion – for example, by burning wood, crops, or waste.
They are either used in their raw form – such as when wooden logs are burned – or converted into pellet fuel. The biomass fuel is burned in a boiler in a similar process to coal-fired power generation.
When controlling combustion, process efficiency depends upon achieving the best possible ratio of air-to-fuel. This allows the heat capture of the boiler to be maximized, and the optimum amount of biomass to be used. Achieving the required air-to-fuel ratio is challenging, as it is constantly affected by changes in loading conditions, fuel composition, fuel particle size, and caloric content. Careful monitoring of oxygen (O2) and combustibles (CO+H2) can ensure efficient combustion of the biomass fuel.