AM-08-18 Regenerator Design to Minimize Catalyst Deactivation and Reduce Emissions

Description:

The FCC unit is composed of a reaction system and a catalyst regeneration system which are interrelated. Even though the reaction system tends to receive more attention with regard to technology improvements, proper design and operation of the regenerator is critical to maintain optimum unit performance, particularly with the tightening of permitted atmospheric emission levels around the globe. The objective of the regenerator is to restore the catalyst activity and selectivity in an environment that minimizes catalyst deactivation while providing the majority of the heat required for the reaction system. There are substantial benefits to be achieved if good regenerator design and operation practices are followed, not the least of which is the level of emissions that are sent out the stack. Two primary issues in regenerator design deal with catalyst deactivation and excess oxygen. Both of these parameters must be minimized to control fresh catalyst addition rates and allow for the most efficient use of air blower capacity. Another phenomenon that must be accounted for in the design is the potential for the unit to “afterburn” which many times will limit unit capacity and result in damaged internals that will reduce the run length. If these issues are addressed properly, emissions levels will be significantly reduced.