This work describes a mathematical compositional model to simulate two-phase flow in gas pipelines with condensation. Algorithms that consider variable physical gas properties as a function of the gas composition are formulated. A module to calculate condensation of gas components is incorporated to the model. Results of various test cases show that the evolution of the holdup is linear time periods simulated. However, this behaviour may not be generalized to high holdup sections since liquid obstruction leads to changes in pressure and mass transfer rates in the gas-liquid interface may show a non-linear time evolution. The proposed model may be used to simulate slow time varying gas flow, and could be an useful tool to study liquid removal methods in gas pipelines.
