An distributor arrangement introduces spent FCC catalyst more uniformly across the dense bed of the regenerator to provide more even contact with regeneration gas in order to avoid hot spots and zones of incomplete combustion. The invention forms a fluidized hopper to collect spent catalyst and a horizontally extended header with multiple horizontally extended outlet arms to place catalyst into the regenerator. The invention may use an aeration means to fluidize the header to further assist catalyst flow. Furthermore, the spent catalyst delivered to the top of the regenerator dense reduces NO.sub.x emissions in the flue gas.