Thermodynamic analysis of the mrc liquefaction plant for the peakshaving of shanghai lng; analyses thermiques du systeme de liquefaction pour l'ecretage de pointe des gaz naturels de shanghai

摘要

To exploit natural gas in the East Ocean of China, the analysis and comparison of various kinds of liquefied NG cycles have been made for the peakshaving plant of Shanghai LNG. The mixed refrigeration liquefied NG cycle (MRC) is considered comparatively more advanced and efficient. This kind of cycle realizes non-isothermal evaporation by using multi-component refrigeration; therefore, the loss of energy is reduced, and the efficiency raised. However, the continuous dephlegmation between the light and heavy components in mixed refrigeration, which occurs in the entire non-isothermal evaporation, changes the refrigeration--not only its phases, but also its components. Thus it is difficult to calculate the thermodynamic properties of MRC. A set of satisfactory programs adopting the modular mehtod have been designed to calculate the MRC process. Based on the results and using the energy analysis concept in the system ,the energy loss and energy efficiency of each piece of equipment was calculated respectively, and the energy flux chart of the whole process was shown. The conclusion provides useful information for the designers and operators of the project.