Development and validation of a model for the simulation of the air drying phenomena in pipelines

The main aim of this research work consists in the development and
validation of a model, based on a numerical method, and its relevant simulation
software, to solve the differential equations governing the drying process of gas
pipelines. The knowledge of this phenomenon represents the key factor for
performing effective pre-commissioning activities in petrochemical industry; in
order to avoid hydrate formation and pipe corrosion, it is in fact necessary to
achieve an effective removal of all water prior the introduction of hydrocarbon
gas. This is normally achieved by performing a bulk dewatering operation,
followed by a drying operation which efficiency is dependent on the air flow
rate, air pressure and temperature. In this paper, the model implemented in a
finite volume-based simulation software, as well as the considerations that have
been made for its development, is presented. Its predictions are compared with
available air drying field data of two existing gas pipeline systems.