含氧LNG气相组分变化规律研究

Study on the vapor component variation in oxygenated LNG

含氧煤层气液化精馏生产得到的LNG含有氧。含氧LNG因吸热或压力降低会出现气化现象,所得气相组分与LNG甲烷浓度、存储压力、吸热量或压力降低值有关。利用HYSYS软件对含氧LNG气化所得气相组分进行模拟研究发现:LNG中甲烷浓度越高,气化后气相中的甲烷浓度也越高;LNG气化量或者压力降低值较小时,气相中非甲烷组分浓度较高,随着气化量或者压力降低值变大,气相中甲烷浓度提高;LNG中氮浓度对气相中的氧气浓度有较大影响;在相同的气化率或压力降低值条件下,LNG存储压力越高,气相中的甲烷浓度也越高。

The LNG liquefied and rectified from oxygen-coalbed gas contains oxygen. As the decalescence or pressure reduction, the oxygenated LNG will be gasified. The gas composition is related to methane concentration in LNG, storage pressure, heat absorption or pressure reduction. HYSYS software was used to simulate the gas components of oxygenated LNG gasification. It is found that the higher the methane concentration in LNG, the higher the methane concentration in the gas phase after gasification; when the gasification amount or pressure reduction of LNG is smaller, the concentration of the non methane component in gas phase is higher, and the methane concentration in gas phase increases with the increase of gasification amount or pressure reduction; the nitrogen concentration in LNG has a great influence on the oxygen concentration in the gas phase; under the same gasification rate or pressure reduction, the higher the LNG storage pressure is, the higher the methane concentration in the gas phase is.