PRICO~?天然气液化技术在海上浮式装置上的应用

较之于岸上(陆地)天然气液化装置,海上浮式天然气液化(FLNG)装置具有投资低、建设周期短、便于迁移及可重复使用等优点,但也面临着易受海上工况及船体晃荡影响等诸多挑战。为此,借助于PRICO~?单循环混合冷剂(SMR)天然气液化工艺技术所具有的较大的灵活性,以及流程简单、易于操作、可满足不同客户的需求、成本更低等优势,运用模块化设计进行了FLNG装置的设备布置,针对海上操作环境对部分关键设备进行了改进,研发出了世界上第一个基于该工艺的浮式天然气液化装置——Exmar FLNG,并进行了现场调试及性能考核。应用效果表明:(1)PRICO~?天然气液化技术能够使FLNG从概念设计实现工程化,并获得更多的发展空间;(2)Exmar FLNG装置集合了天然气处理、天然气液化、LNG储存和装卸功能,工艺流程简短、装置设备数量少、操作简单,具有较短的开停车时间,能较好适应海上恶劣天气及原料气组成变化大的工况,其设计与建造完全符合船级社的相关规范和规定。结论认为,该技术为海洋石油伴生气处理、边际气田和深海气田开发利用提供了一种新的既安全又经济的解决方案。

Refrigerant Distribution Characteristics in Vertical Header of Flat-Tube Heat Exchanger without Internal Protrusion

A heat exchanger that arranges flat tubes horizontally has a vertical header that distributes the refrigerant to each tube. When the heat exchanger works as an evaporator, differences in flow conditions at each branch, such as the ratio and distribution of vapor and liquid, due to the differences in densities and momentums of vapor and liquid in the two-phase flow make equal distribution difficult. This paper describes the distribution characteristics of a four-branch header that has a rectangular cross-section without the internal protrusion of flat tubes in the case of the inflow of the refrigerant R32 from the bottom of the header by using an equipment that can estimate the distribution ratio of the liquid and vapor phase to each branch. This paper also discusses the distribution characteristics on the basis of the flow visualization in the header. The flow visualization shows that a liquid level that contains vapor phase exists in the header and affects the distribution greatly.