Summary of Hydrates in Flow Assurance and Transportation

As the energy industry produces from more hostile environments, such as the ultra-deepwater and the arctic, flow assurance problems will increase. Associated higher pressures, colder temperatures, and higher concentrations of acid gases will cause hydrates to be a larger concern, frequently impacted economically by the high cost of thermodynamic inhibitors at high concentration, so that LDHIs will be more commonly used. 

The industrial flow assurance paradigm is shifting from avoidance, enabled by thermodynamic inhibition, to risk management, enabled by application of kinetics. Examples of time-dependent flow assurance phenomena are kinetic inhibitors, AAs, plug dissociation, and electrical heating of pipelines for plug dissociation. Research support will move from thermodynamics, which is currently acceptably accurate for engineering applications, to time-dependent kinetics. 

The current chapter shows the application of mainly thermodynamic calculations, which have their basis in Chapters 4 and 5. However, as indicated in Chapter 3, a fundamental kinetic model, separated from heat and mass transfer phenomena, has yet to be established, particularly at high concentrations to extend the measurements pioneered in the laboratory of Bishnoi during the last three decades. The generation of such a time-dependent growth model and its application is one of the major remaining hydrate challenges. 

Anselme, M.J., Reijnhout, M.J., Klomp, U.C., WO Patent Application 93/25798 (1993). Argo, C.B., Blaine, R.A., Osborne, C.G, Priestly, I.C., in Proc. SPE International Symposium on Oilfield Chemistry, SPE 37255 Houston, TX, February (2007). Austvik, T., Hustvedt, E., Gjertsen, L.H., Urdahl, O., in Proc. 75th GPA Annual Convention, p. 205 (1997). 

Bakeev, K Myers, R Chuang, J.-C., Winkler, T Krauss, A., US Patent 6242518 (2001). Behar, E., in Gas Hydrate Seminar, Trondheim, Norway, June (1994). 

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