A mathematical model for combustion process in chain-grate furnace of a 35 t/h boiler has been established

taking the gas temperature distribustion and concentration of flue gas comstituents as the boundary conditions for simulation space in the furnace

the temperature and flow field distribution have been simulated by using a computational fluid dynamics software FLUENT and the Selective Non-catalytic Reduction(SNCR) process of the NOx removal in a chain-grate furnace being designed primarily.The comparison of simulated results with actually measured data shows that the typical combustion process on a chain-grate can be simulated and predicted by using the established combustion model.In conventional SNCR process of NOx removal

the space of suitable temperature regions is narrow

the residence time of flue gas in the furnace being shorter

hence

the removal efficiency being lower

but the NOx removal efficiency can be enhanced in a similar operation by suitably adding methane

the NOx removal efficiency can be enheanced by about 9%

and the ammonia leakage can be lowered to 50 μL/L.