Liquid holdup is one of the most critical factors for the formation of pipe effusion, which is closely related to the efficiency of pipe transportation. Nowadays, liquid holdup is mainly estimated according to empirical or semiempirical correlation. Besides, little has been done concerning the accurate prediction of liquid holdup. Therefore, to obtain more precise forecast, this paper proposed a prediction method concerning liquid holdup in horizontal pipe with BP neural network algorithm. Meanwhile, a sensitivity analysis on the key factors impacting liquid holdup was conducted by the combination of the forecast calculation and orthogonal experiment design. The results showed that compared with the empirical calculation (the smallest standard deviation 8.65%), the BP neural network prediction model had achieved more accurate estimation (the average relative error is 7.38%). In addition, the sensitivity analysis indicated that the main indexes including pipe diameter, gas‐ and liquid‐phase superficial velocities, and temperature have significant influence on the liquid holdup. Pipe diameter, liquid‐phase superficial velocity, temperature, and viscosity are positively correlated with the liquid holdup, while pressure and gas‐phase superficial velocity are negatively correlated with it.

In order to select economical and reasonable Boil-off gas (BOG) treatment technology for different types of liquefied natural gas (LNG) stations, this paper introduces the related technologies of BOG treatment without LNG Output. Using the same working fluid and operating parameters to simulate then the six technologies of pulse tube cryocooler recovery, liquid nitrogen recovery, nitrogen expansion recovery, jet refrigeration recovery, mixed refrigerant refrigeration recovery, and direct compression process were compared in terms of power consumption, economy. On the basis of comparative analysis of power consumption, the actual usage of the above process, and with the payback period as the criterion, the BOG treatment technology suitable for different types of LNG stations is obtained. It provides a reference for different types of LNG stations to select appropriate BOG recovery technology, handles the unsolved problem about selecting BOG treatment technology, and puts forward a prospect for the development of BOG treatment technology.