Numerical investigation of distribution uniformity of solid particles in a gas–solid counter flow contact cyclone reactor under cold flow conditions for methanol to propylene

A gas–solid counter flow contact cyclone reactor (GS-CFCCR) was proposed for the methanol to propylene process. It is expected that the mixing of gas–solid phases can be enhanced by the vortices generated by the impinging stream, while the separation can be accelerated by the swirl flow induced by the guide vane. The CFD-DDPM tracer method was adopted to investigate the radial and circumferential distribution uniformity of solid particles in the mixing and reaction chamber. The results indicate that as particles move axially towards the guide vanes, the vortices generated by the impinging flow exhibit increased quantity and reduced size along the axial direction. This evolution causes a progressive deterioration of the radial distribution uniformity along the axial direction, with the mean deviation degree rising from 4.18 to 6.33, while the circumferential uniformity undergoes notable improvement. Furthermore, the effect of the solid particle inlet angle on the distribution performance was investigated. The results indicate that a design with a solid particle inlet angle below 90° is beneficial for achieving better mixing and separation performance. These findings provide a robust theoretical foundation for subsequent thermal modelling experiments, which hold significant potential to enhance industrial efficiency and achieve energy savings in future applications.