A novel hybrid liquefied natural gas process with absorption refrigeration integrated with molten carbonate fuel cell. (24th March 2021)

• Record Type: Journal Article
• Authors: Mehrpooya, Mehdi; Bahramian, Parimah; Pourfayaz, Fathollah; Katooli, Hadi; Delpisheh, Mostafa
• Is Part Of: International journal of low carbon technologies. Volume 16:Number 3(2021)
• Page Start: 956
• Page End: 976
• Publication Date: 2021-03-24
• Subjects: LNG production -- dual mixed refrigerant -- absorption refrigeration -- molten carbonate fuel cell -- super-critical carbon dioxide cycle -- hybrid system; Climatic changes -- Environmental aspects -- Periodicals; Energy industries -- Technological innovations -- Periodicals; Sustainable architecture -- Periodicals; Sustainable buildings -- Periodicals; 621.042
• DOI: 10.1093/ijlct/ctab021
• Languages: English
• ISSNs: 1748-1317

Abstract

Abstract: The production of liquefied natural gas (LNG) is a high energy-consuming process. The study of ways to reduce energy consumption and consequently to reduce operational costs is imperative. Toward this purpose, this study proposes a hybrid system adopting a mixed refrigerant for the liquefaction of natural gas that is precooled with an ammonia/water absorption refrigeration (AR) cycle utilizing the exhaust heat of a molten carbonate fuel cell, 700°C and 2.74 bar, coupled with a gas turbine and a bottoming Brayton super-critical carbon dioxide cycle. The inauguration of the ammonia/water AR cycle to the LNG process increases the cooling load of the cycle by 10%, providing a 28.3-MW cooling load duty while having a 0.45 coefficient of performance. Employing the hybrid system reduces energy consumption, attaining 85% overall thermal efficiency, 53% electrical efficiency and 35% fuel cell efficiency. The hybrid system produces 6300 kg.mol.h −1 of LNG and 146.55 MW of electrical power. Thereafter, exergy and sensitivity analyses are implemented and, accordingly, the fuel cell had an 83% share of the exergy destruction and the whole system obtained a 95% exergy efficiency.