The formation of natural gas hydrates in deep subsea pipelines is one of the most challenging flow assurancernproblems. The development of a comprehensive hydrate model (CSMHyK), which predicts temporal and spatialrnhydrate formation and plugging in flowlines of oil-, water- and gas-dominated systems, will have significant utilityrnin flow assurance. This empowers the engineer to design and assess oil/gas transport facilities, with a focus onrnprevention, management or remediation of gas hydrate formation and blockages. In the current work, we presentrnimprovements to the hydrate aggregation module used for oil-dominated systems, based on experimental data,rnwhich account for temperature, particle-particle contact time, excess water, and the presence of surface activerncompounds. Second, we have extended CSMHyK to water- and gas-dominated systems, and have developedrnfundamental models based on flowloop and laboratory data. In water-dominated systems, we present a new massrntransfer-based growth model and hydrate plugging criterion, based on fluid velocity. In gas-dominated systems, wernpresent a combined heat and mass transfer model for hydrate film growth on pipe walls. These models are applied torna typical well/flowline/riser geometry used in offshore facilities. This model improves our capability to predictrnhydrate formation and blockages, by considering dynamic aggregation phenomena in oil-dominated systems, flowrnregime transition in high water cut systems, and hydrate film growth in gas saturated systems.
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