Abstract: A fluid flow distributor for mixing and distributing gas and liquid over the cross-section of the reactor vessel having an upward fluid flow path. The distributor comprises an inlet pipe for directing quench liquid into and through an inlet feed conduit connected with the reactor and an elliptically-shaped cover plate disposed above the outlet of said conduit, against which the flow from the conduit is directed. A relatively uniform distribution of the gas and liquid to the vessel is obtained by means of the plurality of apertures provided in the plate and the double reflection of the flow from the cover plate and the bottom of the vessel. The inlet conduit includes a plurality of baffles and orifices which aid in the thorough mixing of the quench liquid and the primary or main gas-liquid flow. This is a continuation of application Ser. No. 777,028, filed Mar. 14, 1977 now abandoned.