Abstract: A spent catalyst distributor in a fluid catalytic cracking unit regenerator is self aerated by attaching to the underside of each trough arm a contiguous lip which captures rising aeration fluid and uses the aeration fluid to aerate spent catalyst flowing through the trough arms of the spent catalyst distributor. Orifices in the bottom plate of each trough arm pass the captured aeration fluid up into the spent catalyst flowing within the trough arm. The aeration fluid provides aeration and fluidization of the spent catalyst to facilitate the flow of the spent catalyst through the trough arms of the spent catalyst distributor.