In an apparatus for fluid catalytic cracking a riser having a top and a bottom for fluidizing and cracking a hydrocarbon feed stream by contact with catalyst exits an outlet at the top of the riser. A downer in communication with the outlet of the riser receives cracked hydrocarbon product and catalyst. A swirl duct in communication with the downer has a discharge opening below the outlet for discharging said cracked hydrocarbon product and catalyst. A stream of hydrocarbon feed and a catalyst is passed upwardly in a riser. A stream of gaseous hydrocarbon products and catalyst is directedly downwardly and then the stream of gaseous hydrocarbon products and catalyst are directed to flow in an angular direction to separate gaseous hydrocarbon products from the catalyst.