摘要 |
<p>A stacked FCC reactor-regenerator arrangement is converted into an FCC riser unit having a two-stage regenerator. In this method, a stacked FCC unit having a bottom regeneration vessel, a superadjacent reactor vessel, and a stripping vessel laterally offset from and in open communication with the reactor vessel are used to make a two-stage regenerator having a lower first stage of regeneration, an upper second stage regeneration vessel, and a catalyst cooler for removing heat from the regenerated catalyst. This method involves modifying the vessels in the stacked reactor regenerator arrangement by converting the bottom regeneration into a first stage regeneration vessel, the upper reactor vessel into a second stage regeneration vessel and the stripping vessel into a regenerated catalyst cooler which operates as a downflow type catalyst cooler or a backmix type catalyst cooler. Therefore, apart from the addition of a new riser reactor only relatively minor modifications are necessary to convert the stacked reactor-regenerator arrangement into modern unit having a a two-stage regenerator.</p> |