Sulfur recovery

The Modified Claus Process is the workhorse for sulfur recovery and is used worldwide in more sulfur plants than any other process. The Modified Claus Process can achieve up to 97 percent sulfur recovery efficiency and produces very high-quality sulfur, free of contaminants. In the typical Modified Claus Process, the acid gas feed is partially oxidized to generate sulfur dioxide, which then reacts with the remaining hydrogen sulfide over a catalyst to produce sulfur. Most Claus sulfur plants contain two or three catalytic stages and can be followed by a tailgas cleanup process and/or a UOP Callidus® TTO.  

For higher sulfur recovery efficiencies, UOP Ortloff sulfur recovery processes can be combined with a wide range of tailgas cleanup processes to achieve recovery efficiencies up to 99.95 percent. UOP combines proprietary plant design knowledge and equipment with licensed industry processes for improved operational efficiencies and fewer maintenance problems. These processes include:  

• BP Amoco’s Cold Bed Adsorption (CBA) Process which modifies the standard catalytic Claus reaction by operating below the sulfur dew point temperature for 99-plus percent sulfur recovery  
• Shell Claus Off-gas Treating (SCOT), the most widely recognized amine-based tailgas cleanup process  
• UOP Callidus Tailgas Scrubbing which all but eliminates SOx emissions with a cost-effective, highly reliable system