Off-Gas Utilization for Sulfur Recovery Convertors’ Safety

In a gas plant, the Sulfur Recovery Unit (SRU) utilizes the SuperClaus® process to convert Hydrogen Sulfide to Sulfur. Overall, due to the high temperatures, and the fire risk, the design of the equipment in these processes needs to include a fire suppressing/protection system. In the plant, the SuperClaus® catalytic convertor doesn’t have a method to protect the catalyst in case of a fire erupting. Thus, a proposed a modification would provide the needed protection in terms of capitalizing on a high CO2 off-gas stream from an acid gas enrichment unit. The off-gas is not being utilized in a beneficial manner, and this idea would take advantage of the high CO2 composition, low temperature (110 °F) off-gas and use it to improve the safety of these convertors in case of high temperature/fire. The downstream equipment after the SuperClaus® convertor is a thermal oxidizer and would handle the off-gas used similar to its original pathway (incineration and disposal). The utilization of the off-gas can be linked with process control to divert quantities of the off-gas to the convertor. The CO2 in this case would act as a quench to cease any fire eruption, and wouldn’t damage the catalyst. The idea is a filed patent and considered a novelty in the industry. The utilization of the once unused CO2 from acid gas enrichment process is a way of capitalizing on carbon emissions for a circular use in the industry. An alternative would be to use Nitrogen instead, however, in comparison to individual plant production and the cost behind it would deem it superficial to the option of utilizing the aforementioned idea.