Study of the robustness of a low-temperature dual-pressure process for removal of CO2 from natural gas

The growing use of energy by most of world population and the consequent increasing demand for energy are making unexploited low quality gas reserves interesting from an industrial point of view. To meet the required specifications for a natural gas grid, some compounds need to be removed from the sour stream. Because of the high content of undesired compounds (i.e., CO2) in the stream to be treated, traditional purification processes may be too energy intensive and the overall system may result unprofitable, therefore new technologies are under study. In this work, a new process for the purification of natural gas based on a low temperature distillation has been studied, focusing on the dynamics of the system. The robustness of the process has been studied by dynamic simulation of an industrial-scale plant, with particular regard to the performances when operating conditions are changed. The results show that the process can obtain the methane product with a high purity and avoid the solidification of carbon dioxide.