Study on the Comparison of New and Used Reliquefaction System of Boil-Off-Gas by LNG Cold Energy

냉열을 이용한 LNG 증발기체 BOG 재액화 신공정과 기존공정에 관한 비교연구

  • Received : 2010.02.03
  • Accepted : 2010.02.28
  • Published : 2010.02.28

Abstract

BOG(Boil Off Gas) is formed about 0.05 vol%/day from LNG(Liquefied Natural Gas) tanks of LNG receiving terminal. To recycle the BOG using direct contacting, Previously the quantities of LNG and BOG is mixed at the ratio of 11:1 by mass. However simple this process uses, there is the difficulty of processing operation resulted from decrease of using LNG in summer. To complement these shortcomings, Advantages of the process are investigated by comparison of cost and analysis of the indirect contact method using LNG cold energy. It was studied that principles and types of development using LNG cold energy which is abandoned in the carburettor and found how to contact each to find the appropriate cold energy development process. Therefore, in this research, the indirect contact method will be investigated the feasibility of a comparative analysis by using HYSYS.

LNG (Liquefied Natural Gas)기지의 LNG 저장탱크에서 BOG (Boil Off Gas)가 약 0.5 vol%/day로 자연적으로 생성된다. 이를 회수하기 위해서 기존에는 LNG와 BOG를 1:12의 질량비로 직접 접촉시켜 액화시켰다. 이 공정은 단순하지만 하절기에는 LNG 사용량 저하로 인해 공정운영의 어려움이 있다. 이러한 단점을 보완하기 위해 대안된 LNG 냉열을 사용하는 간접접촉방식을 HYSYS를 이용하여 분석해보고 직접접촉방식과 BOG 재액화 효율비교를 통해 분석하여 유리한 공정을 도출하였다.

Keywords

References

  1. J. Heestand, C. W. Shipman and J. W. Meader, "A predictive model for rollover in stratified LNG tanks", AIChE J, 29, pp 199-207 (1983). https://doi.org/10.1002/aic.690290205
  2. K. Nasrifar and M. Moshfeghian, "Vapor-liquid equilibria of LNG and gas condensate mixtures by the Nasrifar- Moshfeghian equation of state", Fluid Phase Equilibria, 200, 203-216 (2002) https://doi.org/10.1016/S0378-3812(02)00028-6
  3. 김동혁, 하종만, 박영, 윤익근, 백영순, "LNG 기지에서 BOG 액화공정 개선에 관한 연구", 한국가스학회지, 5(3), 23-28, (2001)
  4. 신명욱, "액화 천연가스 탱크의 증발가스 발생량과 안전성에 관한 모사 연구", 서울대학교 공학석사학위논문 (1999).
  5. John R. Howell, Fundamentals of Engineering Thermodynamics, SI ver., McGraw-Hill. (2005).
  6. Warren L. McCabe, Unit Operations of Chemical Engineering, 5th ed., McGraw-Hill, (2001)
  7. H. S. Kim, "Economical analysis on the size and propulsion system of LNG carrier", Technical Trend of The Gas Industry, KOGAS, 17, pp 69-76 (2005).
  8. 김용갑, "중장기 발전용 천연가스 적정 요금체계 연구", 한국가스공사[공편], 2004