Numerical Simulation on Effect of Heating Temperature upon the Gaseous Flow in a SCR Catalytic Filter Device 2009-01-2628
Selective catalytic reduction (SCR) and diesel particulate filter (DPF) as a compact system are used to reduce NOx and soot emissions, respectively. The aim of this study is to develop a SCR catalytic filter device for reducing simultaneously NOx and soot emissions from a combustor. In order to attain the optimal NOx conversion, the amount of ammonia must be managed to the amount of NOx on catalyst surface. If the amount of ammonia is higher than that of NOx, ammonia slip will be presented. Therefore, the uniform ammonia distribution around the catalyst is one of the challenges for the SCR application. Temperature is also a sensitive parameter in the reaction rate of NOx with ammonia. In this paper, the heating effect on the gaseous flow in the SCR catalytic filter device is studied with the uniformity of ammonia distribution. As a result, it is found that the temperature around catalytic filters is lower at Re = 4255 than that at Re = 64. The result also shows that the mixing index decreases as increasing the heating temperature in SCR device.