ShareAbsorption refrigeration offers an energy-efficient alternative for natural gas and hydrogen liquefaction
According to a review article published in Energies, absorption refrigeration integrated into the liquefaction processes could reduce power consumption and carbon emissions by up to a third for natural gas liquefaction, and up to a fourth for hydrogen liquefaction.
Natural gas and hydrogen production plants are generally far from the application site. Gas liquefaction offers a solution for long-distance transport and storage. For instance, once liquefied and chilled at around -161°C, the volume of natural gas is reduced by a factor of 10 to 600 (depending on the operating pressure in the gas phase) and storage is possible in large non-pressurised, space efficient but well-insulated tanks [1]. However, conventional liquefaction processes use electricity-driven compression refrigeration technology, which require high energy consumption and can result in significant carbon dioxide emissions.
A review article published in Energies examined absorption refrigeration as an energy-efficient alternative in both natural gas and hydrogen liquefaction processes [2]. The authors analysed the progress of absorption refrigeration in terms of working pairs, cycle configurations, and heat and mass transfer in main components.
The results showed that:
- Driven by industrial waste heat or renewable thermal energy, the absorption refrigeration cycle can be integrated into conventional natural gas liquefaction processes, including SMR, C3MR, DMR, cascade, and expansion refrigeration liquefaction processes. By providing precooling temperatures of about −13 to −54 °C, it results in a reduction in specific power consumption (SPC) and carbon emissions by 10–38% and 10–36%, respectively.
- Integrated into conventional hydrogen liquefaction processes, such as Linde–Hampson, Claude, and Joule–Brayton liquefaction processes, the absorption refrigeration cycle can provide precooling temperatures of about +9 to −59 °C. This results in a reduction in in specific power consumption (SPC) and carbon emissions by 2–24% and 5–24%, respectively.
The review article is available in open access in Energies or in FRIDOC.
Sources
[1] Liquefied natural gas: an essential cryogenic industry at the heart of the energy transition. 53rd Informatory Note on Refrigeration Technologies. https://iifiir.org/en/fridoc/liquefied-natural-gas-an-essential-cryogenic-industry-at-the-heart-of-147200
[2] Wang L, He L, He Y. Review on Absorption Refrigeration Technology and Its Potential in Energy-Saving and Carbon Emission Reduction in Natural Gas and Hydrogen Liquefaction. Energies. 2024; 17(14):3427. https://doi.org/10.3390/en17143427