Numerical Investigation of Secondary Flow in a Cyclone Reactor for Alkylation Catalyzed by Ionic Liquid

Abstract

The axial velocity and streamline distribution in the cyclone reactor for ionic liquid alkylation are simulated using the Reynolds stress and Eulerian multiphase flow models. The secondary flow rates are calculated based on the formation mechanism. Moreover, the impacts of operating parameters on the secondary flow are investigated. Obvious secondary flows are observed in zero axial velocity wave zone (ZAVWZ). The best back-mixing occurs in the inlet mixing zone with a high secondary flow rate. Meanwhile, the main separation of two phases occurs in the cone zone with poor secondary flow. The secondary flow of two phases is enhanced with an increase in the total flow rate. However, the secondary flow of the light phase is inhibited with an increase in the overflow ratio. The appropriate feed ratio can promote the formation of secondary flow. The best mixing of two phases in the reactor is attained at F = 0.40, E = 1.00, and Q = 4.0 m3/h.

Study of the Mixing Degree in the Cyclone Reactor for Alkylation Catalyzed by Ionic Liquid based on the Information Entropy

“…The swirling flow is enhanced, and the separation process is accelerated with the total inlet flow increasing, causing a decrease in the mixing time. Notably, the flow field in the cone section becomes disordered and circulation flow is enhanced at Q = 4.0 m 3 /h, resulting in a longer mixing time in the cone section, as shown in Figure b. It can be summarized that the mixing degree becomes better with an increase in the total inlet flow, but the side reactions in the cone section may be promoted at Q = 4.0 m 3 /h.…”

“…The peak "A" of the mixing entropy appears. Additionally, back-mixing occurs in the column section, 33 and the mixing time is relatively high in the column section. The other light phase flows downward with the heavy phase.…”