Effect of different operating conditions on the performance of a 32 MW woodchip-fired grate boiler.

Abstract This paper presents a numerical study on the effect of different operating conditions (excess air coefficient, in-furnace pressure and air ratio in zone 5) on a woodchip grate-firing boiler. First, the numerical modeling approach is validated with experimental measurement of in-furnace temperature as well as exhausted gas emissions. Subsequently, parametric studies are carried out using the validated numerical modeling approach. The modeling results indicate that, the boiler overall efficiency can be improved through adjusting the values of the operating conditions of interest. It is suggested to improve the boiler efficiency through reducing excess air coefficient, increasing in-furnace pressure and enhancing ash cooling in zone 5. [ABSTRACT FROM AUTHOR]