Radial flow reactor with moving catalyst bed - has collection scoops at bottom of bed for transferring catalyst to withdrawal conduits

摘要

A reactor for contacting fluids with catalyst particles comprises a cylindrical vessel contg. cylindrical inner and outer catalyst retaining screens defining an outer annular fluid distribution volume, an intermediate annular catalyst bed and an inner cylindrical fluid collection volume. Used catalyst is gradually withdrawn from the bottom of the catalyst bed and replaced with fresh catalyst supplied to the top of the bed. The used catalyst is removed through catalyst withdrawal conduits distributed in a pattern encircling the inner catalyst withdrawal conduits distributed in a pattern encircling the inner catalyst retaining screen. The top of each conduit has a catalyst collection scoop located at 5-60 degrees to the horizontal with its open end facing the inner screen. Used in hydrocarbon conversion processes, e.g. the isomerisation or dehydrogenation of n-paraffins or in naphtha reforming. The reactor has a minimal no. of stagnant zones because the scoops collect used catalyst particles from the regions adjacent the inner screen where stagnant, ineffective particles tend to collect, e.g. during inward vapour flow.