The Mechanism And Kinetics Research On NO Reduction By Char Reburning

At present pulverized coal reburning is a practical and feasible low-NOx combustion technique in Chinese power station boiler for meeting environmental protection. The heterogeneous NO reduction by char plays an important role in pulverized coal reburing. The porosity and specific area of three different granular char made of blended coal are measured with N₂ isothermal adsorption method, and the fractal dimension of char is worked out, which is between 2.67 and 2.96. Based on fractal theory, the author sets up a non-linear diffusion kinetic modeling for NO reduction by char reburning, which includes some parameters such as fractal dimension D , diffusion modulusφ_p , efficient diffusion coefficient De , inner and outside diffusion efficient factorη_p,η_e. Taking into account the effects of mass diffusion, the kinetic modeling takes numerical simulation on NO reduction by char reburning and the intrinsic kinetics parameters are figured out. The numerical simulations on NO reduction by other two granular char reburning are performed and the validity of the kinetic modeling and the intrinsic kinetics parameters is validated ultimately.