Sustainable boil-off gas utilization in liquefied natural gas production: Economic and environmental benefits. (10th May 2021)

• Record Type: Journal Article
• Authors: Al-Sobhi, Saad Ali; AlNouss, Ahmed; Shamlooh, Mohamed; Al-Nuaimi, Khalid; AlMulla, Abdullah; Khraisheh, Majeda
• Is Part Of: Journal of cleaner production. Volume 296(2021)
• Publication Date: 2021-05-10
• Subjects: Liquefied natural gas (LNG) -- Boil-off gas (BOG) recycling -- Resources and energy management -- Process simulation -- Economic and environmental benefits (EEB) -- Nitrogen rejection unit (NRU); Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2021.126563
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Boil-off gas (BOG) causes negative environmental impacts related to gas streams flaring in the liquefied natural gas (LNG) industry. This study addresses the resources and energy management and discusses the economic and environmental benefits of recycling the BOG stream in the LNG production process. Three BOG utilization scenarios and strategies are considered. The first scenario is a separate cooling cycle dedicated to re-condensing the BOG before introducing it to the nitrogen rejection unit (NRU). The second strategy is recycling the BOG before the liquefaction section. The third scenario is recycling the compressed BOG directly in the NRU without re-condensation. Three NRU configurations—flash drum, single distillation column, and double distillation column—are analyzed. The assessment is conducted by the steady-state ASPEN HYSYS simulation of an AP-X LNG production flowsheet. In an illustrative case study, various design alternatives are analyzed for recycling 52, 000 metric tons of BOG annually while considering and combining economic, energy, and environmental objectives. Graphical abstract: Image 1 Highlights: BOG utilization is an attempt to reach the zero flaring targets and to attain resources conservation initiatives. There are numerous benefits in recycling BOG in the LNG production process. Multiple BOG recycling allocations and options were identified and analyzed. The implementation of reigouros simulation and technoeconomic-environmental analyses help to select amongst options.