Method and apparatus for desulfurizing fuel gas

A hydrocarbon fuel gas hydrodesulfurizer assembly comprising:

• a) an inlet manifold for directing a mixture of the fuel gas and hydrogen into the assembly;
• b) a catalyst bed communicating with said inlet manifold so as to receive a stream of the hydrogen and fuel gas, said catalyst bed containing a nobel metal catalyst operable to convert sulfur and sulfur compounds in said hydrogen and fuel gas mixture to hydrogen sulfide;
• c) a heat exchanger section adjacent to said catalyst bed, said heat exchanger section being operable to heat the hydrogen and fuel gas stream prior to the latter entering said catalyst bed;
• d) a gas conduit for passing a high temperature reformed process gas stream through said heat exchanger section, said heat exchanger section being operable to cool said process gas stream as the latter flows through said heat exchanger section;
• and
• e) a shift converter section adjacent to said heat exchanger section, said shift converter section being operable to receive cooled process gas from said heat exchanger section, and said shift converter section being operable to remove carbon monoxide from said cooled process gas in an exothermic reaction so as to produce heat which is at least partially taken up in said heat exchanger section.

A method for removing sulfur and sulfur compounds from a fuel gas stream, said method comprising the steps of:

• a) providing a mixture of the fuel gas and hydrogen into the assembly;
• b) providing a catalyst bed containing a nobel metal catalyst operable to convert sulfur and sulfur compounds in said hydrogen and fuel gas mixture into hydrogen sulfide;
• c) passing said fuel gas and hydrogen mixture through said catalyst bed;
• d) providing a heat exchanger section adjacent to said catalyst bed;
• e) passing a high temperature reformed process gas stream through said heat exchanger section so as to cool said process gas stream as the latter flows through said heat exchanger section and to concurrently heat said fuel gas and hydrogen mixture;
• f) providing a shift converter section adjacent to said heat exchanger section;
• and
• g) directing cooled process gas from said heat exchanger section into said shift converter section and removing carbon monoxide from said cooled process gas in an exothermic reaction in said shift converter section so as to produce heat which is at least partially taken up in said heat exchanger section.