Chapter 2 - Flow Assurance Issues

Abstract

One of the most important design issues for offshore pipelines in deepwater are the operational hazards associated with multiphase fluid transportation. These issues usually do not arise in shallow water where water temperatures are higher and hydrostatic pressures are lower, and so a new engineering discipline was essentially created when operators started to develop deepwater fields. Wax, hydrates, and asphaltenes are the three main threats to flow assurance. Hydrate problems are nearly universal in deepwater production, while the extent of wax and asphaltene varies widely between projects. Hydrate blockages are most common in gas and gas condensate systems but can also occur in oil systems. Subsea systems are designed to foresee the problems that may arise during all stages of production over its lifetime, but prognostications are uncertain and unanticipated issues may arise that were not considered in the design. Flow assurance is a major design consideration for subsea wells.