Performance of Polymer Hydrogels Incorporating Thermodynamic and Kinetic Hydrate Inhibitors

This study investigates the hydrate formation characteristics of hydrogel particles containing thermodynamic or kinetic hydrate inhibitors. Hydrate onset time, hydrate fraction in the liquid phase, and torque changes were determined from the experiments using a high pressure autoclave. To simulate the mixture of water and liquid hydrocarbon encountered in subsea pipelines, decane was added corresponding to an initial 60% water-cut. In the liquid phase a high hydrate fraction was observed in the pure water + decane mixture with a local maximum in torque. For the hydrogel decane mixture, a lower hydrate fraction was observed, and the torque remained stable during the hydrate formation. The addition of 0.5 wt % of a commercial kinetic hydrate inhibitor (Luvicap) to the aqueous phase (with no hydrogel) delayed the hydrate onset time, but several spikes in the torque were observed during the …