Advanced Simulation on Techniques for Predicting Gas Behavior in LNG and NGL Operations

Abstract

When it comes to Liquefied Natural Gas (LNG) and Natural Gas Liquids (NGL) processing plants, the precise forecast of gas behaviour is a key component in the enhancement of the safety, efficiency and reliability of plant operation. Tightly coupled with the large dynamism of thermodynamic properties of natural gas mixtures at cryogenic temperatures and pressures, the standard methods of estimating will not always serve the interests of natural gas mixtures at high pressures and cryogenic temperatures, as they do not capture the nature of complexities in phase nature, composition, and flow dynamics. This paper discusses various highly detailed simulation methods that have become prominent in LNG and NGL practices, which take such extensive modeling like thermodynamic modeling, molecular modeling, and compound process simulators like Aspen HYSYS, and OLGA. The importance of choosing and using suitable equations of the state, the use of dynamic simulation to make predictions in real-time and the inclusion of simulation with a control system to be able to respond toward operations is stressed. The industrial feasibility of the various methods and tradeoffs in computation are also reviewed. Results indicate that the effective use of simulation tools can not only help increase the accuracy of prediction but also achieve proactive decision making in complex conditions of gas processing. This marks the research, the necessity of further development of the simulation structure to meet the changing needs of the operation, varying gas mixture.