CYNARA acid gas removal membrane systems reduce installation and operating costs and increase efficiency
CYNARA acid gas removal membrane systems efficiently and selectively permeate acid gases to separate them from produced gas streams that contain 5- to 95-mol% acid gas. The membrane systems are compact, largely self-contained, and mounted on skids, which reduces installation costs. The use of these membrane systems also reduces operating costs by eliminating the need for liquid chemicals and the logistics of their transport, storage, and disposal.
The unique CYNARA PN-1 dual-zoned acid gas removal membrane system, which was jointly developed with Petronas, works on the principle of diffusion and solubility-based separation. It combines two different membrane cores in a single 30-in-diameter membrane element, with each membrane optimized to selectively permeate different concentrations of acid gas endemic to the feed gas. The CYNARA PN-1 membrane permeates the highest concentrations of inlet acid gas in Zone 1 and directs lower concentrations of acid gas into Zone 2 to efficiently optimize the treatment of gas streams with irregular levels of CO2 and H2S.
Prior to deployment, the technology was tested and validated for three years at a Schlumberger-operated gas processing facility in Texas. During evaluation, it was demonstrated that the dual-core technology offers 8% to 10% more CO2 removal and throughput compared with standard 30-in single-core membranes and provides approximately four times higher CO2-removal capacity compared with 16-in membranes.
The Schlumberger OneSurface team designed the gas plant’s AGRS to treat up to 700 MMcf/d of raw gas containing up to 25-mol% CO2 and to deliver product gas with <8% CO2, C3 = RSH (mercaptans), and C4 – RSH content. The system comprises two pretreatment trains of 350-MMcf/d nominal capacity, followed by five modular CYNARA PN-1 membrane sections that remove CO2 from inlet gas to produce the product gas (nonpermeate). The overall design of the CYNARA PN-1 acid gas removal membrane system was tailored for operation flexibility to address variations in feed gas composition and flow rate. With technical support of the Schlumberger global team of experts, the entire system was fabricated and delivered to Petronas by 2015, was installed and commissioned on time in 2016, and began operation in early 2017.