Tail Gas Treating Technologies to Meet Ultra-low SO₂ Emission Standards

The requirement to meet ultra-low SO₂ emission standards, even lower than World Bank limits, is becoming more and more prevalent for new refinery and natural gas developments and/ or certain regions. At the same time, more-complex, sour gas fields are being developed as sweet fields become depleted, and in the oil sector crudes are also becoming heavier and more sour.

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 Catalysts & Technologies is continuously developing and/ improving its portfolio of gas treatment technologies.

Technologies Tailored Toward Your Objectives

Shell Catalysts & Technologies 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 the development of the next generation SCOT ULTRA technology to give even further flexibility for operators to achieve the perfectly tailored solution to their processing needs and objectives.

Shell CANSOLV TGT+ technology can be part of an integrated sour gas treating solution, enabling ultra-low SO₂ emissions and the capture up to 99.99% 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.

SCOT ULTRA employs sharper design rules, improved catalyst technology and a new advanced proprietary JEFFTREAT-ULTRA solvent. The new technology lowers operating costs, achieves higher performance in warmer climates, and improves resilience to process changes and upsets. The technology can be retrofitted to existing tail gas units as well as new grassroots applications.

Shell Catalysts & Technologies has licensed more than 300 SCOT units, which has enabled the team to build up a strong background in using tail gas treating for meeting SO₂ emission limits. As both a designer and an operator of these units, Shell is well equipped with the knowledge and expertise necessary to get the best results and offers more than just a design and delivery service.