Method For Producing Synthesis Gas by Steam Reforming

A process for producing synthesis gas by steam hydrocarbon reforming carried out in a combustion chamber of a reforming furnace comprising burners and tubes, said process comprising:

• filling said tubes with catalyst,
• placing said filled tubes vertically in the combustion chamber, said tubes having walls, an upper end and a lower end,
• passing a mixture of said hydrocarbons with steam through said tubes,
• introducing said mixture into the tubes at said upper ends,
• removing the synthesis gas produced partly at said tube bottom end,
• placing the burners so as to transfer the heat from the combustion to the hydrocarbon/steam mixture through said tube walls, and
• inverting the tubes, at the end of a first period of operation, so as to increase their expected lifetime under normal conditions of use.