Pinning in Radial Flow Moving Bed Reactor

For certain types of chemical reactors where the catalyst decays rapidly but
reversibly, continuous operation is possible by use of a Radial Flow Moving Bed
Reactor (RFMBR). A Continuous Catalyst Regeneration (CCR) reformer unit is one of
the industrial units using the RFMBR. RFMBR can be simply described as a reactor
where the catalyst flows downward by gravity and the feed gas flow radially across the
reactor and leaves through a center pipe.
In this type of reactor there is an upper limit on the gas flowrate imposed by a
mechanical phenomenon called "pinning". "Pinning" is when the catalyst particles are
pinned against the center pipe due to high gas velocity. Understanding the pinning and
the fuctors influencing it is required for the CCR reformer process engineers before
doing any plant optimization. By conducting the experiment we can study the effect the
flowrate of gas to the maximum pinned film thickness.