Sulfur Recovery Process by Worley Parsons

Application: Sulfur recovery from typical Claus gas rich in hydrogen sulfide (H2S) from industrial gases, and sour-water stripper (SWS) gas.

Description: DEGsulf is an improved Claus process plus tail-gas treatment that allows sulfur recovery rates of 99.8+% with just two catalytic reactors. Downstream of the Claus furnace and waste-heat boiler (1) are two catalytic reactors (3A / B) integrating the Claus step and a sub-dewpoint tail-gas treatment. Its main feature is the use of internally cooled reactors, which control the reaction temperatures by special welded plate-heat exchangers in the catalyst beds. The first bed (3A) operates at high temperatures, the second bed (3B) below the sulfur dew point. This reactor adsorbs sulfur and must be regenerated eventually, which is done by switching the cool second reactor to the position of the hot first reactor and vice versa. The use of proprietary 4-way valves (2A / B) makes the switch-over between adsorption and regeneration simple and reliable. The produced sulfur is recovered in the sulfur condenser (4) and collected in the sulfur pit (7). Prior to entering the 2nd reactor the process gas is reheated (5). The desulfurized gas is incinerated (6).

Conventional Claus catalysts are applied. They ensure up to 99.85% sulfur recovery. In no-operating mode, there are no dead pipes. This avoids the related problems of corrosion and sulfur plugging.

Typical feed gas is Claus gas rich in H2S. DEGsulf is capable of handling wide fluctuations of feed gas flows and compositions. Turn-down ratios up to 6/1 have been realized. Sulfur recovery rates up to 99.8+% were observed. The process operates fully automatic, including the switch-over.

Economics: Capital cost depends on the amount of feed gas and on the required sulfur recovery rate. Products are bright yellow sulfur and steam. Utility consumptions are very low, as in a conventional Claus process.

Licensor: Worley Parsons.