Comparison of Operation Performance of LNG Reliquefaction Process according to Reverse Brayton Cycle and Claude Cycle

  • Shin, Young-Gy (Department of Mechanical Engineering, Sejong University) ;
  • Seo, Jung-A (Department of Mechanical Engineering, Sejong University) ;
  • Lee, Yoon-Pyo (Energy Mechanics Research Center, Korea Institute of Science and Technology)
  • Published : 2009.12.31


A dynamic model to simulate LNG reliquefaction process has been developed. The model was applied to two candidate cycles for LNG reliquefaction process, which are Reverse Brayton and Claude cycles. The simulation was intended to simulate the pilot plant under construction for operation of the two cycles and evaluate their feasibility. According to the simulation results, both satisfy control requirements for safe operation of brazed aluminum plate-fin type heat exchangers. In view of energy consumption, the Reverse Brayton cycle is more efficient than the Claude cycle. The latter has an expansion valve in addition to the common facilities sharing with the Reverse Brayton cycle. The expansion valve is a main cause to the efficiency loss. It generates a significant amount of entropy associated with its throttling and increases circulation flow rates of the refrigerant and power consumption caused by its leaking resulting in lowered pressure ratio. It is concluded that the Reverse Brayton cycle is more efficient and simpler in control and construction than the Claude cycle.



  1. M. K$\ddot{u}$ver, C. Clucas and N. Fuhrmann, Evaluation of propulsion options for LNG carriers, 2002, The 20th International Conference & Exhibition for the LNG, LPG and Natural Gas Industries (GASTECH 2002)
  2. Hamworthy Ltd., 2007, LNG systems for marine application, Hamworthy Brochure
  3. Y. Shin and Y. P. Lee, 2009, Design of a boil-off natural gas reliquefaction control system for LNG carriers, Applied Energy, Vol. 86, Issue I, pp. 37-44
  4. Y. Shin, J. A. Seo, and Y. P. Lee, 2008, Comparison of Dynamic Operation Performance of LNG Reliquefaction Processes based on Reverse Brayton Cycle and Claude Cycle, SAREK Joumal, Vol. 12, No. 12, pp. 775-780
  5. ALPEMA, 2000, The Standards of the Brazed Aluminium Plate-Fin Heat Exchanger Manufacturers' Association (ALPEMA), 2nd ed., ALPEMA
  6. E. W. Lemmon, M. O. McLinden and M. L. Huber, 2006, REFPROP (Reference Fluid Thermodynamic and Transport Properties). NIST Standard Database 23, Version 7.1, Physical and Chemical Division; National Institute of Science and Technology
  7. J. W. Moon, Y. P. Lee, Y. W. Jin, E. S. Hong and H. M. Chang, 2007, Cryogenic Refrigeration Cycle for Re-Liquefaction of LNG Boil-Off Gas, International Cryocooler Conference, Boulder, CO., USA