| The present research investigates the possibility of the industrial use of gas hydrates for natural gas storage. The method of storing natural gas in hydrates has distinct advantages of low operating pressures, safety, slow dissipation of gas in case of leaking, and relatively high theoretical capacity. Stirred reactors currently used by researchers have the following shortcomings: low water conversion, viscous slurries, slow hydrate formation rate, and potentially expensive and difficult scale-up.; The following breakthroughs have been achieved in this work by the use of a low concentration micellar solution: (1) rapid hydrate formation in an unstirred system; (2) reaction of interstitial water to maximize conversion; (3) increase of the gas-liquid interfacial area by the adding of sodium dodecyl sulfate; (4) self-packing of hydrate particles by adsorption as hydrate forms. At 550 psig and 36°F, 156 volumes of gas at STP per volume of hydrate storage capacity was obtained within three hours, 87% of guest-gas cavities were filled in the hydrate crystal. The hydrate formation rate was estimated using a mathematical model, the pressure exponents were calculated to be 2.89 for ethane gas hydrate formation and 2.75 for natural gas hydrate formation, similar to a stirred system. The results make the process of natural gas storage in hydrates potentially attractive. |
