The requirement to meet ultra-low SO2 emission standards, even lower than World Bank limits, is becoming more and more prevalent for new natural gas developments and/ or certain regions. At the same time, more-complex, sour gas fields are being developed as sweet fields become depleted.
Addressing these challenges while ensuring that increasingly stringent SO2 emission limits are met in the future, requires technology capable of ultra-high levels of sulphur recovery, even when dealing with difficult gas streams. Next to meeting the increasingly stringent SO2 emission limits, proposed technology should also satisfy the requirement of lowest life cycle cost. In this respect, Shell Global Solutions is continuously developing and/ or improving its portfolio of gas treatment technologies.
Shell Global Solutions has utilised its extensive knowledge and experience of designing and operating Shell Claus off-gas treating (SCOT*) units since the 1970s to hone the technology for this purpose. The company has also extended its tail gas treating portfolio with the addition of the Shell CANSOLV* TGT+ technology and with the current development of the next generation SCOT.
These technologies are capable to meet stringent SO2 emission limits for a range of emission requirements (even better than World Bank limits). Depending on the case, e.g. feedstock composition, required SO2 emission, each of these technologies has its own competitive edge.
Shell CANSOLV TGT+ technology can be part of an integrated sour gas treating solution, enabling ultra-low SO2 emissions and the capture of 99.9+% of the overall sulphur present in sour gas streams while minimising the complexity of the process line-up. This system sits at the back end of the gas processing line-up and serves as the final destination to capture SO2 from all the plant’s sour gas streams routed to the incinerator, as illustrated in Figure 1.