Liquefied natural gas(LNG)is an important energy source and occupies an important proportion in natural gas consumption,therefore,the selection of appropriate liquefaction processes and related optimization should be ...Liquefied natural gas(LNG)is an important energy source and occupies an important proportion in natural gas consumption,therefore,the selection of appropriate liquefaction processes and related optimization should be seen as subjects of great importance.Accordingly,in the present review,we provide a comparative and critical analysis of the current status of natural gas liquefaction technology through examination of the advantages and disadvantages associated with three natural gas liquefaction processes(namely,the cascade liquefaction cycle,the expander-based cycle and the mixed refrigerant cycle).It is shown that the energy consumption related to the cascade refrigeration cycle is the lowest.Compared with it,the mixed refrigerant cycle has the advantages of being a simpler process,with less units,low investment cost and low requirements in terms of refrigerant purity.The expander-based cycle can be started and stopped quickly and simply,but the power consumption is relatively high.展开更多
LNG—FPSO(LNG Floating Production Storage and Offloading Unit,又称FLNG)是集海上液化天然气的生产、储存、装卸和外运为一体的新型浮式生产储卸装置。作为LNG—FPSO的核心技术,海上天然气液化工艺将对该装置的建造运营费用、运行...LNG—FPSO(LNG Floating Production Storage and Offloading Unit,又称FLNG)是集海上液化天然气的生产、储存、装卸和外运为一体的新型浮式生产储卸装置。作为LNG—FPSO的核心技术,海上天然气液化工艺将对该装置的建造运营费用、运行稳定性和整个系统的安全性产生很大的影响,而现有的3种基本类型的天然气液化工艺(氮膨胀、混合冷剂和级联式制冷液化工艺)都不能完全符合海上天然气液化工艺的设计标准。为此,根据海上作业的特殊工况,组合模拟了6种适用于海上天然气液化的工艺流程,并从制冷剂流量、功耗、关键设备数量、天然气流量敏感性、天然气组成敏感性、易燃制冷剂储存和海上适应性等方面对各流程进行了比较,根据计算结果及对各流程的定性分析,优选出带预冷的氮膨胀液化工艺[即丙烷预冷双氮膨胀流程、混合制冷剂—氮气膨胀(并联)流程和混合制冷剂—氮气膨胀(串联)流程]为LNG—FPSO装置的首选工艺,且发现随着预冷深度的增加,该工艺的海上适应性减弱,功耗降低,处理能力增强。展开更多
基金This work was supported by the Science Development Funding Program of Dongying of China(Grant No.DJ2020009).
文摘Liquefied natural gas(LNG)is an important energy source and occupies an important proportion in natural gas consumption,therefore,the selection of appropriate liquefaction processes and related optimization should be seen as subjects of great importance.Accordingly,in the present review,we provide a comparative and critical analysis of the current status of natural gas liquefaction technology through examination of the advantages and disadvantages associated with three natural gas liquefaction processes(namely,the cascade liquefaction cycle,the expander-based cycle and the mixed refrigerant cycle).It is shown that the energy consumption related to the cascade refrigeration cycle is the lowest.Compared with it,the mixed refrigerant cycle has the advantages of being a simpler process,with less units,low investment cost and low requirements in terms of refrigerant purity.The expander-based cycle can be started and stopped quickly and simply,but the power consumption is relatively high.
文摘LNG—FPSO(LNG Floating Production Storage and Offloading Unit,又称FLNG)是集海上液化天然气的生产、储存、装卸和外运为一体的新型浮式生产储卸装置。作为LNG—FPSO的核心技术,海上天然气液化工艺将对该装置的建造运营费用、运行稳定性和整个系统的安全性产生很大的影响,而现有的3种基本类型的天然气液化工艺(氮膨胀、混合冷剂和级联式制冷液化工艺)都不能完全符合海上天然气液化工艺的设计标准。为此,根据海上作业的特殊工况,组合模拟了6种适用于海上天然气液化的工艺流程,并从制冷剂流量、功耗、关键设备数量、天然气流量敏感性、天然气组成敏感性、易燃制冷剂储存和海上适应性等方面对各流程进行了比较,根据计算结果及对各流程的定性分析,优选出带预冷的氮膨胀液化工艺[即丙烷预冷双氮膨胀流程、混合制冷剂—氮气膨胀(并联)流程和混合制冷剂—氮气膨胀(串联)流程]为LNG—FPSO装置的首选工艺,且发现随着预冷深度的增加,该工艺的海上适应性减弱,功耗降低,处理能力增强。
