It is well known that the formation of clathrate hydrates in oil and gas
industries often clog deep sea pipelines, which results in severe threats
toward the operation safety, slows deep sea drilling and exploration, and
add to the expense of the given project. Currently, there are only two
methods by which to inhibit such formations: thermodynamic and kinetic
inhibitors. Thermodynamic inhibitors, such as methanol, ethylene glycol, and
sodium chloride, shift the equilibrium hydrate dissociation/stability curve
(also known as the hydrate-aqueous liquid-vapor equilibrium curve) to a
lower temperature, thus avoiding the hydration formation altogether.
However, since exploration and production moves to deeper seas, temperature
and pressure conditions in the filed become in favor of hydrate formation,
i.e., the temperature is colder and the pressure is higher, and the addition
of this type of inhibitor would be expensive and environmentally prohibitive
the inhibitor concentration required to prevent hydrate formation becomes
very high. Because of this, the use of thermodynamic inhibitors is often
very expensive and may be environmentally harmful. Kinetic inhibitors, such
as Polyvinylpyrrolidone (PVP) and Poly-N-vinylcaprolactam (PVCap), work by
slowing the nucleation and growth rates of the hydrate formation, thus
slowing the hydrate formation in the pipelines. In deep sea exploration,
these inhibitors slow the hydrate formation for a time period longer than
the residence time of the gas in hydrate-prone section of pipeline. The
existing kinetic inhibitors, however, are still not believed to give an
economic solution especially at high pressure and large degree of
supercooling. Because of this, the use of kinetic inhibitors in deep waters
is generally regarded as impractical.
Fortunately, researchers at the University of Wyoming have found an
alternative method by which to prevent clathrate hydrate formation. We have
discovered a method by which ionic liquids are used to shift the
hydrate-aqueous liquid-vapor equilibrium curve to a lower temperature (which
helps to prevent hydrate formation) while, at the same time, retard hydrate
nucleation and growth rates. By acting as both kinetic and thermodynamic
inhibitors, these ionic inhibitors are much more effective and cost
efficient than either inhibitor used alone.
If you would like to learn more about this novel fuel cell technology and
how your company may apply it in commercial situations, please contact the
Director of the University of Wyoming Research Product Center,
Davona Douglass. We would be please to share further details.
Research Products Center
Dept. 3672
1000 E. University Ave.
Laramie, WY 82071
(307)766-2520
Fax: (307) 766-2530
e-mail: WyomingInvents@uwyo.edu