LNG-FPSO용 CO2-N2O-N2 천연가스 액화사이클 특성

Abstract

This paper presents a new natural gas liquefaction cycle which utilizes carbon dioxide(CO2), nitrogen monoxide (N2O), and nitrogengas(N2) cycles. A liquefaction cycle with staged compression was designed and simulated using HYSYS software for improving cycle efficiency. This included a cascade cycle with a three-stage compression consisting of a CO2, a N2O and a N2 cycle. These cycles were compared with an optimized staged compression process. The Compressor work, specific energy, and COP (Coefficient of Performance) of the cascade cycles were compared and analyzed. The new CO2, N2O and N2 liquefaction cycle is also compared to other natural gas liquefaction cycles including the Phillips optimized cascade cycle and a multi-staged cascade cycle using a Propane, Ethylene and Methane. The specific energy of the new cascade cycle which utilizes a three-stage compression process is 26% lower than that of basic single-stage cycle. Also, the new liquefaction cycle requires less power for the same liquefied natural gas (LNG) quantity produced by other methods.