Dynamic Simulation Of The Self-pressurized Procss In The LNG Vaporization Station Storage Tank

With tensions and environmental problems of the world’s energy situation isincreasingly grim, natural gas for its clean, efficient features, such as gradually intoall aspects of national production and life. In order to meet the growing demand fornatural gas, LNG (Liquefied Natural Gas, referred to as LNG) as a major source ofnon-pipeline natural gas, has been developing rapidly in China. In the technologicalprocess of LNG Vaporizing Station, since the tank’s pressurized process is a veryimportant step, however, the domestic research for self-pressurization process is toolittle, engineering design for the selection of the self-pressurized vaporizer isbasically virtue experience, no specific algorithms and normative guidance. Atpresent, the domestic equipment for the vaporization research stations are mostlyseparate study areas for tanks or self-pressurized vaporizer, lack the research ofself-pressurization process for heat transfer, mass transfer, flow resistance and otheraspects of the research, the lack of a self-pressurized vaporizer in self-pressurizedaspects of functional improvement and optimization. Therefore, to further optimizethe process of self-pressurized LNG vaporization station, providing more theoreticalguidance for the selection of the self-pressurized vaporizer, the self-pressurizationprocess dynamic simulation studies are very practical significant.This paper identifies the composition of LNG according to actual gas sourcecomponents, respectively selecting the calculations models and mixed rules for thethermodynamic properties and migration properties of natural gas. Described thephase equilibrium calculations and the reverse solve the problem, using Matlabwritten each parameter for calculation program, and lay a good foundation for thesubsequent simulation.CoMParison of existing cryogenic tanks thermodynamic model domestic andabroad, established a physical and mathematical model suitable forself-pressurization process simulation, selecting models for heat transfer and flowresistance calculated of the pressurized pipeline. For specific examples, simulate forthe self-pressurized process. Calculate the heat transfer and flow resistance forpressurized pipeline, drawn steady-state and dynamic-state curves of pressure,temperature, and other parameters along the pressurized pipeline. Determine theflow of pressurized gas from the pressurized process for tanks computing for heatand mass transfer, obtained the tank pressure, temperature, gas quality, gas densitygraph. Analysis of several important factors that affect the process of self-pressurized, obtained pressure change rule from the process of self-pressurized.According to the simulation results, proposed a specific algorithm that meetsproject accuracy in selection of self-pressurized process. Calculate the100m3and150m3LNG storage tank self-pressurization process for different conditions,obtained some guidance conclusions to the selection of self-pressurized vaporizer.Finally, make some feasible suggestions for the self-pressurized process.