Increase The Flexibility Of Your Claus Unit

By Gary J. Nagl, Vice President, Merichem

With the introduction of sophisticated ratio control, O2 enrichment, improve burner design, etc., great strides have been made in the ability of Claus units to adjust to rapidly changing feed conditions, which are experienced in both petroleum refineries and natural gas processing facilities. However, even with these advancements, some process applications still challenged Claus units with their ability to adjust to large turndown ratios while maintaining high removal and on-stream efficiencies. By incorporating a liquid redox process, such as the LO-CAT® process, together with a Claus unit, turndown ratios of 100%, removal efficiencies of 99.9 % and on-stream efficiencies approaching 100% can be achieved. In addition for certain applications, the typical Claus incinerator can be eliminated, which will greatly reduce CO2 and SO2 emissions and the energy requirements to operate the incinerator. All of this can be accomplished without having to recycle gas back to the Claus.