Device for manufacturing a product gas containing hydrogen and carbon oxide

Device for use in manufacturing a product gas containing hydrogen and carbon oxide from a feedgas mixture comprised substantially of hydrocarbons mixed with steam, said device comprising a vertically extending vessel having an interior space, a horizontally extending tubesheet connected in said vessel for dividing the interior space into a first chamber on one side of said tubesheet and a second chamber on an opposite side of said tubesheet, a plurality of axially extending reformer tubes having closed ends and open ends located within the interior space and extending through said tubesheet from said first chamber into said second chamber, said tubesheet forming a distribution chamber for supplying a feedgas mixture into said reformer tubes, said tubesheet comprising an inner hollow body and an outer hollow body surrounding said inner hollow body on all sides, an inlet line connected to and communicating with an interior of said inner hollow body for the admission of a feedgas mixture into the interior of said inner hollow body, said inner hollow body having a flow opening for communication between the interior of said inner hollow body and a space between the interior of said inner hollow body and a space between said inner hollow body and said outer hollow body, and a connecting tube connected between the closed end of each of said reformer tubes and said outer hollow body for communicating the interior of said reformer tubes with the space between said inner and outer hollow bodies, a jacket laterally enclosing and spaced outwardly from each said reformer tube for forming an annular space extending along each said tube from the first chamber through the tubesheet and for at least a part of the axial length of each said tube within said second chamber for establishing communication between said first and second chambers, and an outlet nozzle connected to said first chamber for the outlet of product gas from the second chamber.