Abstract: A reforming reactor for an endothermic process including a plurality of reformer tubes allowing a flow of hydrocarbons and at least one further fluid inside the tubes is provided. Wherein the reformer tubes contain in their interior a catalyst for the conversion of the hydrocarbons and the at least one further fluid to synthesis gas, and a means for heating the reformer tubes. Wherein at least a portion of the plurality of reformer tubes is provided with one or more elements for enlarging the outer surface area of a reformer tube, and the catalyst includes a structured catalyst. Also an endothermic process for the production of synthesis gas, including allowing a flow of hydrocarbons and at least one further fluid inside a plurality of reformer tubes, and heating the plurality of reformer tubes to convert said hydrocarbons and the at least one further fluid to synthesis gas.

Abstract: A process is proposed for producing synthesis gas with reduced steam export by catalytic steam reforming of a hydrocarbonaceous feed gas with steam in a multitude of reformer tubes in a burner-heated reformer furnace to form a steam reforming flue gas. This process includes a configuration of the reformer tubes as reformer tubes with internal heat exchange and the use of a structured catalyst. For amounts of export steam between 0 and 0.8 kg of export steam per mN3 of hydrogen produced, these features interact synergistically when particular steam reforming conditions are selected.