Transport of hydrate slurry at high water cut

Aline Melchuna (1, 2, 3) , Ana Cameirão (1, 2, 3) , Yamina Ouabbas (1, 2, 3) , Jean-Michel Herri (1, 2, 3) , Philippe Glenat (4)

1 SPIN-ENSMSE - Centre Sciences des Processus Industriels et Naturels
2 PROPICE-ENSMSE - Département PROcédés Poudres, Interfaces, Cristallisation et Ecoulements
3 LGF-ENSMSE - Laboratoire Georges Friedel
4 CSTJF - Centre scientifique et Technique Jean Feger

Oil transportation in pipelines at the end of field production life implies to flow high quantities of water which represents the dominant phase. The process of crystallization of gas hydrates in this system needs to be studied and compared to the opposite one widely studied in the literature where water is the dispersed phase. The laboratory is equipped with the Archimede flow loop where the hydrate crystallization and transport are monitored. The flow loop is equipped with pressure and temperature probes, to observe the transport with differential pressure drop probes, with an FBRM probe (Focused Beam Reflectance Measurements), an ATR probe (IR measurement) and a PVM probe (Particle Video Microscope). We have performed a parametric study based on the water content (60% - 90%), and liquid flow rates (200L/h and 400L/h) in order to observe the crystallization of methane hydrates from an emulsion of liquid Kerdane (C11 - C14) and liquid water. A set of experiments without and with commercial AA-LDHI (Anti- Agglomerant - Low Dosage Hydrate Inhibiter) were compared. For experiments without AALDHI, when the amount of hydrates reaches a critical zone, flow is stopped by either impossibility to transport (too viscous slurry) or hydrates sticking to the flow loop walls. In experiments with AA-LDHI we observe the benefice of adding a chemical dispersant to maintain flow and prevent instabilities.

Mots clés: gas hydrates; flow assurance; pipelines; high water cut; dispersant; AA-LDHI

Domaines: Génie des procédés

Aline Melchuna, Ana Cameirão, Yamina Ouabbas, Jean-Michel Herri, Philippe Glenat. Transport of hydrate slurry at high water cut. The 8^th International Conference on Gas Hydrates, Jul 2014, Pékin, China. pp.T5-16. ⟨hal-01065852⟩