THE MERLUZA GAS PIPELINE -A COMPLETE MULTIPHASE FLOW ANALYSIS COUPLING PIC LAUNCHING WITH PRESSURE CONSTRAINED SURVIVAL ANALYSIS

摘要

This work describes the requirements and comments the results of a set of pipeline flow numerical simulations, for the offshore Merluza wet gas pipeline, located at Santos Basin, state of Sao Paulo, Brazil. The work was conceived under the two-phase flow domain, and has used a well known commercial two phase flow numerical simulator. This pipeline is somewhat singular when compared to the average wet gas pipeline, as there is a considerable amount of condensate being carried, requiring a frequent launching of pigs. Besides, the capacity request at the pipeline's tail is variable, even though it fits to an approximate stable cycle of demand. This cycling nature has required a survival analysis, for both packing and drafting operations, accounting for sometimes four pigs within the line, at the same time. Additionally, there is a pressure constraint downstream to the pipeline, due to the operational limits of the slug catcher, turning compulsory to have the survival cycle adjusted, in order to fully commit to this restriction. Finally, the results obtained with the simulation fits properly to the measured operational data, and allows the operational programmer to optimize the launching of pigs, as well as to take advantage of the maximum pipeline capacity.