(US4678600-A)      Process for the steam reforming, in a reforming reactor, of hydrocarbons by passing a feed stream comprising steam and one or more hydrocarbons, as process gas (I), at steam reforming conditions and under external supply of heat through a given vol. of steam reforming catalyst (II), to form a prod. stream rich in H2, comprises a) passing gas (I) through a first portion of catalyst (II) making up 25-75% of (II), heat needed for the endothermic reactions occurring in gas (I), and for heating gas (I), being supplied partly from a moderately hot flue gas as defined under b), and partly from the prod. steam: b) subsequently passing the gas (I), partly reformed in step a), through the rest of catalyst (II), the heat needed for the further endothermic reactions, and for heating gas (I) being supplied by a hot flue gas generated by combustion of a fluid fuel, the hot flue gas being hereby cooled to form the moderately hot flue gas used in step a).    USE/ADVANTAGE -   Heat from the prod stream is used more economically. (9pp)s    (US4830834-A)      A reactor for the catalystic reforming of hydrocarbons comprises:- (a) a thermally insulated, vertically disposed, cylindrical pressure vessel having a bottom, a shell wall a removable top; (b) a centrally disposed burner for generating a hot flue gas at the bottom of the vessel surrounded by a vertically extending wall to define a combustion chamber, the combustion chamber having an outlet near the top of the vertically extending wall; (c) a flue gas outlet in the sheel wall; (d) first passageway means connecting the outlet of the combustion chamber to the flue gas outlet, the first passageway means including a first portion of the vertically extending wall of the combustion chamber defines a wall of the first portion and the interior of th e the shell wall defines a wall of the second portion of the first passageway means; (e) a feed gas inlet in the shell wall; (f) a vertically disposed outer catalyst compartment having an inlet and an outlet and spaced from the shell bottom and top, and disposed inward of and in heat exchange contact with the second portion of the first passageway means; (g) second passageway means connecting the feed gas inlet and outer catalyst compartment inlet; (h) a vertically disposed inner catalyst compartment having an inlet and an outlet and spaced from the shell bottom and top and disposed outwardly of the in heat exchange contact with the first protion of the first passageway means; (i) a vertically disposed third passageway means connecting the outer catalyst compartment outlet and the inner catalyst compartment inlet; (j) a product outlet for removing processed feed gas from the pressure vessel; and (k) fourth passageway means connecting the inner catalyst compartment outlet to the product outlet . (-pp)    (JP95098642-B2)      Process, and reactor, for the steam reforming of hydrocarbons in a reforming reactor by feeding steam and one or more hydrocarbons as process gas under steam reforming conditions with an external heat supply through a given volume of steam reforming catalyst to form a hydrogen-rich prod. stream, by (a) passing the process through a first portion (being 25-75%) of catalyst, heat needed for the endothermic reactions occurring in the process gas and for heating the process gas being supplied partly from a moderately hot flue gas (as under (b)) and partly from the product stream; then (b) passing the process gas partly reformed in step (a) through the remaining portion of the catalyst, the heat needed for the further endothermic reactions and heating the process gas being supplied by a hot flue gas generated by combustion of a fluid fuel, the hot flue gas being thereby cooled to form the moderately hot flue gas employed in step (a).    ADVANTAGE -   A more economic method for supplying the heat required for the endothermic reaction is by indirect heat exchange using heat from the prod. stream in combination with heat from a hot flue gas.