Improvement of Hydrodynamics Performance of Naphtha Catalytic Reforming Reactors Using CFD

Document Type : Research Note


Process Development & Control Group, Process Development & Equipment Technology Division, Research Institute of Petroleum Industry (RIPI), Tehran, I.R. IRAN


Due to high applicability of the fixed bed catalytic naphtha reforming reactors, hydrodynamic features of this kind of reactors with radial flow pattern are improved in this work by utilising computational fluid dynamics technique. Effects of catalytic bed porosity, inlet flow rate and flow regime through the bed on the flow distribution within the system are investigated.It is found that the first reactor among three fixed bed reactors in series is working inappropriately. It is due to the effects of recirculating flow on the hydrodynamics. In addition, flow distribution at the end of each bed is discovered to be non-uniform. By applying computational fluid dynamics technique to the system and manipulating effective parameters, not only vortices are removed at the end of each bed, but also flow distribution through the first reactor is considerably improved. A new internal modification for all reactors is proposed, which allows reactors to become overloaded with the catalyst. Subsequently, inlet flow rate can rise by 10-15 per cent over its current value.


Main Subjects

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