Liquefied natural gas plants based on nitrogen expansion cycles

Information is provided on Kriogenmash’s capabilities for building large-capacity liquefied natural gas (methane) plants based on external cryogenic nitrogen expansion cycles with turboexpander-compressor unit (TECU) stages and many years of experience in developing and employing medium- and high-output cyrogenic air fractionating plants (AFP) with TECUs. Various flow diagrams of liquefied natural gas (LNG) plants with one to four TECUs are examined. The major advantages of such plants are noted, e.g., power consumption of 0.38–0.45 kWh/kg of LNG, capital costs 2–3 times less than with mixed cycles, etc. The Russian gas industry can successfully start introducing large-capacity LNG plants based on external nitrogen expansion cycles, the experience of whose creation is confirmed by developments of domestic AFPs.