SQU research advances energy-efficient LNG production for offshore use

2026-03-01 - 18:37

Muscat – A researcher at Sultan Qaboos University has developed a liquefied natural gas (LNG) production technology aimed at improving energy efficiency and cutting indirect carbon dioxide emissions in small-scale and offshore facilities. Dr Muhammad Abdul Qyyum, Assistant Professor at the university’s College of Engineering, led the project titled ‘CO2 precooled dual-phase expander refrigeration cycles for offshore and small-scale LNG production’. The study won in the Energy and Industry category under the PhD segment at the 12th National Research Award organised by the Research and Innovation Authority. Small-scale and offshore LNG systems are among the most energy-intensive segments of the gas value chain. In remote and offshore settings, high power demand for liquefaction increases operating costs and emissions. The research proposes integrating carbon dioxide-based precooling with dual-phase expander refrigeration cycles. By using CO2 as a refrigerant in the precooling stage, the system improves thermal integration and reduces overall power consumption, lowering indirect emissions linked to LNG production. According to the findings, combining CO2-based precooling with a dual-phase expander cycle using an ethane–nitrogen refrigerant mixture delivered measurable gains in process performance. The configuration reduced specific energy consumption and thermodynamic losses, indicated by lower exergy destruction. It also lowered capital and operating costs compared with conventional small-scale LNG processes. Among the tested configurations, the CO2-precooled ethane–nitrogen cycle showed the strongest balance between energy efficiency, thermodynamic performance and economic viability, positioning it as a potential option for offshore and modular LNG applications. Dr Abdul Qyyum said adopting CO2-based precooling in small-scale and offshore LNG systems could offer a practical pathway to reduce energy use, operating costs and indirect emissions. He stressed the importance of optimal refrigerant selection, pressure ratio optimisation and effective thermodynamic integration at the design stage to improve sustainability and competitiveness. The research was published in the peer-reviewed journal Energy, issued by Elsevier. The study was conducted in collaboration with Dr Ahmad Naquash, Eng Noman Raza Sial and Prof Moonyong Lee of Yeungnam University. The development comes as LNG producers face mounting pressure to enhance efficiency and reduce emissions across the value chain, particularly in offshore and distributed projects.