Experimental Simulation Analysis of Propane Pre-Cooling and Dual Nitrogen Expansion Liquefaction Process Adaptable for Floating Liquid Natural Gas (FLNG) in Deep Water Gas Field in the South China Sea

Experimental Simulation Analysis of Propane Pre-Cooling and Dual Nitrogen Expansion Liquefaction Process Adaptable for Floating Liquid Natural Gas (FLNG) in Deep Water Gas Field in the South China Sea

Liquefied natural gas

Liquefaction

Propane

Nitrogen

Energy utilization

Offshore oil well production

Natural gasoline plants

Offshore technology

Expansion

Floating liquefied natural gas

Refrigeration

Heat transfer performance

Laws and legislation

Offshore gas fields

Intellectual property

Refrigerating machinery

The liquefaction process is one of the key technologies of offshore FLNG device and is charged by patent protection of a few companies. Because of special offshore operational environment, the choice of FLNG liquefaction process is different from that of onshore. The liquefaction process in FLNG should be suitable for the marine environment and the oil and gas properties in the South China Sea. In this paper, static and dynamic performances of propane pre-cooling and dual nitrogen expansion liquefaction process with independent intellectual property rights have been verified by the simulation in two experimental loops with small scale 2000m3/d and middle scale 20000m3/d respectively. Dynamic simulation experimental measures for key liquefied devices such as placing the cold box on the swing platform and propane changing the difference of liquid level between the separation tank, and the cold box, are used to verify offshore adaptability of the liquefaction process. It is indicated through static experiments in a small experimental loop that the liquefaction rate of 93% and energy consumption of 0.42kw.h/m3 can be reached. Dynamic experimental results through the cold box placed on the swinging platform show that the heat transfer performance of the cold box is not affected when rolling amplitude of the FLNG hull is up to 3.6 degrees. The mid-scale experimental simulation shows that the liquefaction process has the advantages of simple debugging process, convenient operation, quick shutdown and restart, flexible operation, and good adaptability to offshore operating parameters, and can realize 3 sets of simulation of refrigeration cycles. Through static and dynamic experiments in both small and middle scale experimental loops, the propane pre-cooling and dual nitrogen expansion liquefaction process with independent intellectual property rights is verified to have characteristics of high liquefaction rate, low energy consumption and good offshore adaptability, and can be used to develop offshore gas field and faraway from onshore in the South China Sea. 2017, Editorial Office of Ship Building of China. All right reserved.

297-306

58

Ship Building of China

2017

Yu, Xichong

Xie, Bin

Li, Yuxing

Liu, Miaoer

Wang, Chunsheng

Wang, Qing

Li, Yan

journalArticle

10004882