NOVELTY - A one-step fluidized-bed reactor for producing hydrogen from methane by a steam reforming process, has an elongated vertical chamber; and a plate disposed horizontally within a lower portion of the reactor. The plate has an upper fluidized-bed chamber; a lower gas-manifold chamber; high-velocity, rocket-style impinging injector(s) for injecting reactants into the fluidized-bed chamber; and based-bleed orifices for injecting streams of reactants.    USE - For producing hydrogen from methane by a steam reforming process.    ADVANTAGE - The inventive reactor effectively produces a commercially large-scale pure hydrogen gas (44). It provides good uniform dispersions of the methane, steam, and calcium oxide reactants with the contents of the bulk-fluidized bed at or near the bed's injectors, thus ensuring reliable reactor operation.    DETAILED DESCRIPTION - A one-step fluidized-bed reactor for producing hydrogen from methane (32) by a steam reforming process, comprises an elongated vertical chamber (12); and a plate (14) disposed horizontally within a lower portion of the reactor. The plate defines an upper fluidized-bed chamber (16); a lower gas-manifold chamber (18); high-velocity, rocket-style impinging injector(s) (20) for injecting reactants into the fluidized-bed chamber; and based-bleed orifices (22) disposed around the impinging injector and extending perpendicular through for injecting respective streams of reactants from the lower gas-manifold chamber into the upper fluidized-bed chamber. An INDEPENDENT CLAIM is also included for a dense-phase flow splitter (200) for splitting a flow of a stream of a gas having particles of a solid entrained in the gas at or near a static-bed bulk density of the particles into equal constituent dense-phase flows, comprising an elongated annular inlet tube having an inlet end, an outlet end, and an internal cross-sectional area; and elongated annular outlet tubes. The outlet tubes have respective internal cross-sectional areas that are equal to each other, and the sum of which is equal to that of the inlet tube; respective diameters of not less than 0.25 inch; and respective inlet ends coupled to the outlet end of the inlet tube such that the flow of the stream through the inlet tube is equally divided among the outlet tubes. Any change in the axial direction of the flow of the stream through the flow splitter does not exceed about 10degrees. The gas comprises steam (34), and/or methane. The solid comprises calcium oxide.    DESCRIPTION OF DRAWING(S) - The figure is a schematic, cross-sectional elevation view of a one-step fluidized-bed reactor.    Elongated vertical chamber (12)    Plate (14)    Upper fluidized-bed chamber (16)    Lower gas-manifold chamber (18)    High-velocity, rocket-style impinging injectors (20)    Base-bleed orifices (22)    Nickel-plated alumina particles (24)    Methane (32)    Steam (34)    Steam and methane mixture (35)    Hydrogen gas (44)    Outlet end of the outlet tube of a dense-phase flow splitter (212)    Dense-phase flow splitter (200)