A fines injection apparatus, a fluid catalytic cracking (FCC) system having a fines injection apparatus, and a method for using the same are provided. In one embodiment, a FCC system includes a FCC unit, a fines collector, and a fines injector coupled to the fines collector for retuning the fines recovered in the fines collector to the FCC unit. In another embodiment, an apparatus for injecting fines into a FCC system includes a fines separator coupled to an effluent stream and an injection apparatus coupled to a regenerator. A conduit is provided for delivering collected fines from the fines separator to the injection apparatus. In yet another embodiment, a method for injecting fines into FCC system includes collecting fines from a waste stream of a FCC system, automatically transferring the collected fines to a fines injection apparatus, and periodically injecting the transferred fines into the FCC system.