【摘要】 催化剂结构尺寸直接影响了催化性能。借助AVL BOOST软件,重点关注了催化剂长度、横截面积和孔密度等关键结构参数对SCR系统NOx转化效率和压降的影响规律。研究结果表明,长度、横截面积和孔密度的变化对NOx转化效率和压降的变化影响显著。增大长度和孔密度,有利于提高NOx转化效率,但对压降产生不利影响;增大横截面积,可提高NOx转化效率和减小压降。孔密度和体积一定,横截面积与长度比值的变化对NOx转化效率几乎无影响,但压降随着比值的增大而减小。最后,结合空间尺寸、空速范围、排气条件等限制条件,为实船柴油机SCR催化剂结构设计提出合理方案。更多还原

【Abstract】 The structure parameters of catalyst directly affect its catalytic performance. By using AVL BOOST and orthogonal experiment, emphasis was focused on the effect of length of catalyst, cross-sectional area and pore density on NOx conversion efficiency and pressure drop. The result indicates that the above three structural parameters have significant influence on them. Increasing the length and pore density is beneficial to improving the reduction of nitrogen oxides; nevertheless, it will also boost the pressure drop.Besides, increasing the cross-sectional area of catalyst can achieve higher NOx conversion efficiency and lower pressure drop at the same time. What is more, the ratio of cross-sectional area to length almost has no effect on the NOx conversion efficiency for a certain pore density and volume of the catalyst. However, the pressure drop decreases with increasing ratio. In the end, a rational SCR catalyst structure selection is put forward for a marine diesel engine while considering some limitations such as spatial size, space velocity and exhaust condition.更多还原