Optimization and Thermodynamic Analysis of the Dual Mixed Refrigerant Process of the Natural Gas Liquefaction

Document Type : Research Article

Authors

1 Imam Khomeini international university, Qazvin, Iran

2 mam Khomeini international university, Qazvin, Iran

3 Imam Khomeini International University

Abstract

Natural gas liquefaction processes require a lot of investment and operation costs and are part of the energy-consuming industries. In this research, parameters such as refrigerant component, inlet and outlet pressure to compressors were optimized in the dual mixed refrigerant system to reduce operating costs. The optimized system was then evaluated by exergy to obtain the amount of exergy loss in various components of the system, finding illustrate the highest exergy losses were in compressors, heat exchangers, aftercoolers and throttle valves, respectively. The reason for the high loss of exergy in the compressors is their low polytropic efficiency. Exergy analysis showed that exergy loss in the main cycle heat exchanger, is 4% higher than that of the pre-cooling cycle heat exchanger, which is due to the higher temperature difference between input and output flows in the main cycle heat exchanger. Analysis of the effect of the size of the heat exchanger, which highly affects investment costs, on the specific power consumption is carried out and the results showed that this effect is minimum at the optimum point and increases proportionally to the distance from the optimum point.

Keywords

Main Subjects

References

[1]  T.-V. Nguyen, E.D. Rothuizen, W.B. Markussen, B.J.A.T.E. Elmegaard, Thermodynamic comparison of three small-scale gas liquefaction systems, 128 (2018) 712-724.
[2]   B.B. Kanbur,  L. Xiang, S. Dubey,  F.H.  Choo, F.J.R. Duan, s.e. reviews, Cold utilization systems of LNG: a review, 79 (2017) 1171- 1188.
[3]    B.B. Kanbur, L. Xiang, S. Dubey,  F.H. Choo, F.J.A.E. Duan, Thermoeconomic and environmental assessments of a combined cycle for the small scale LNG cold utilization, 204 (2017) 1148-1162.
[4]  M.S. Khan, I. Karimi, M.J.A.T.E. Lee, Evolution and optimization of the dual mixed refrigerant process of natural gas liquefaction, 96 (2016) 320-329.
[5]  Y.A. Husnil, M.J.J.o.C.E.o.J. Lee, Synthesis of an optimizing control structure for dual mixed refrigerant process, 47(8) (2014) 678-686.
[6]  A.H. Moradi, M. Mafi, M. Khanaki, Sensitivity analysis of peak-shaving natural gas liquefaction cycles to environmental and operational parameters, Modares Mechanical Engineering, 13 (2015) 298-278. (In Persian)
[7] M. Wang, R. Khalilpour, A.J.E.C. Abbas, Management, Thermodynamic and economic optimization of LNG mixed refrigerant processes, 88 (2014) 947-961.
[8]  R. Nibbelke, S. Kauffman, B.J.O. Pek, g. journal, Double mixed refrigerant LNG process provides viable alternative for tropical conditions, 100(27) (2002) 64-64.
[9]  B. Ghorbani, M.-H. Hamedi, M. Amidpour, R.J.I.J.o.R. Shirmohammadi, Implementing absorption refrigeration cycle in lieu of DMR and C3MR cycles in the integrated NGL, LNG and NRU unit, 77 (2017) 20-38.
[10]  J.-H. Hwang, M.-I. Roh, K.-Y.J.C. Lee, C. Engineering, Determination of the optimal operating conditions of the dual mixed refrigerant cycle for the LNG FPSO topside liquefaction process, 49 (2013) 25-36.
[11]  M.S. Khan, I. Karimi, A. Bahadori, M.J.E. Lee, Sequential coordinate random search for optimal operation of LNG (liquefied natural gas) plant, 89 (2015) 757-767.
[12]    S.S. Pwaga, Sensitivity analysis of proposed LNG liquefaction processes for LNG FPSO, Institutt for energi-og prosessteknikk, 2011.
[13]    T. Morosuk, S. Tesch, A. Hiemann, G. Tsatsaronis, N.B.J.J.o.N.G.S. Omar, Engineering, Evaluation of the PRICO liquefaction process using exergy-based methods, 27 (2015) 23-31.
[14]    B. Karamloo, S. Seyed Abbas, m. Mafi, H. Manafi, Effect of Refrigerant Component Leakage on the Performance of Double Stage Mixed Refrigerant LNG Process, Jurnal of Mechanical Engineering Tabriz university, (1396) 267-276. (In Persian)
[15]    C.L. Newton, Dual mixed refrigerant natural gas liquefaction with staged compression, in, Google Patents, 1985.
[16]    M.S. Khan, I. Karimi, D.A.J.J.o.N.G.S. Wood, Engineering, Retrospective and future perspective of natural gas liquefaction and optimization technologies contributing to efficient LNG supply: A review, 45 (2017) 165-188.
[17]    M.S. Khan, S. Lee, G. Rangaiah, M.J.A.e. Lee, Knowledge based decision making method for the selection of mixed refrigerant systems for energy  efficient  LNG  processes,  111 (2013) 1018-1031.
[18] B. Ghorbani, M. Mehrpooya, R. Shirmohammadi,   M.-H.J.J.o.C.P.   Hamedi, A comprehensive approach toward utilizing mixed refrigerant and absorption refrigeration systems in an integrated cryogenic refrigeration process, 179 (2018) 495-514.
[19] A.H. Aslambakhsh, M.A. Moosavian, M. Amidpour, M. Hosseini, S.J.E. AmirAfshar, Global cost optimization of a mini-scale liquefied natural gas plant, 148 (2018) 1191- 1200.
[20] R. Song, M. Cui, J.J.E. Liu, Single and multiple objective optimization of a natural gas liquefaction process, 124 (2017) 19-28.
[21] D.-Y. Peng, D.B.J.I. Robinson, E.C. Fundamentals, A new two-constant equation of state, 15(1) (1976) 59-64.
[22] G. Venkatarathnam, K. Timmerhaus, Cryogenic mixed refrigerant processes, Springer, 2013.
[23]H. Tan, S. Shan, Y. Nie, Q.J.C. Zhao, A new boil-off gas re-liquefaction system for LNG carriers based on dual mixed refrigerant cycle, 92 (2018) 84-92.
[24]   C. Sun, Y. Li, H. Han, J. Zhu, S.J.E.T. Wang, F. Science, Experimental research on the adaptability of liquid natural gas spiral wound heat exchanger in dual mixed refrigeration liquefaction process, 98 (2018) 124-136.
[25]H. Ding, H. Sun, S. Sun, C.J.C. Chen, Analysis and optimisation of a mixed fluid cascade (MFC) process, 83 (2017) 35-49.
[26]      K.-Y. Lee, J.-C. Lee, J.-H. Hwang, J.-H. Cha, M.-I. Roh, Determination of the optimal operating condition of the dual mixed refrigerant cycle at the pre-FEED stage of the LNG FPSO topside liquefaction process, in: The Twenty-first International Offshore and Polar Engineering Conference, International Society of Offshore and Polar Engineers, 2011.
[27]    A. Bejan, G. Tsatsaronis, M. Moran, M.J.Moran, Thermal design and optimization, John Wiley & Sons, 1996.
Amirkabir Journal of Mechanical Engineering
Volume 52, Issue 9
December 2020
Pages 2357-2368

Files

Share

How to cite

Statistics