Hydrates are crystal-like compounds that may form any time natural gas components contact water at high pressure and low temperatures. These conditions are almost always encountered in deep water hydrocarbon production systems, therefore hydrates remain the number one flow assurance issue related to deep water offshore production. The formation of a hydrate plug can occur very rapidly and may cost millions of dollars in remediation costs and production losses. Therefore the widely used flow assurance strategy is to avoid the formation of hydrates altogether, usually using thermal insulation and/or thermodynamic hydrate inhibitors (THIs) such as mono-ethylene-glycol (MEG) or methanol (MeOH). Subsea trees, manifolds and jumpers are particularly at risk because of the more rapid cool down time upon shut-in and the difficulty to insulate them efficiently. Typical jumper geometries also include low-spots where water may accumulate (Figure 1), increasing the risk of hydrate plug formation upon restart.

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