The design of oil and gas field pipeline systems for deepwater developments are invariably based on the cool down period during the production facilities unplanned shut down. The prediction of hydrate temperature for the production fluids is based on the reservoir fluids composition. The composition of the production fluids along the length of the pipeline and riser vary during both a planned as well as an unplanned shut down. This is due to the phase slippage between the produced fluids i.e. OIl, Water and Gas and the terrain profile change. As a result the hydrate temperature will vary along the length of the pipeline, not only due to the change in pressure but also due to the composition change. This knowledge is used to optimize the cool down time to the hydrate dissociation point along the length of the pipeline and also to minimize the pipeline insulation requirements. This principle is used to mitigate the hydrate formation potential during an unplanned production system shutdown combined with a new operational strategy using the Gas to Liquids Absorption technology. The proposed methodology has the potential to eliminate the use of large quantities of hydrate inhibitors such as Methanol and also to simplify operating procedures. Case examples for typical deepwater development infrastructure will be provided to illustrate the concept discussed and presented in this paper

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