Effect of docusate sodium on growth kinetics of methane hydrate

In this experiment, the green promotion in the static system was investigated by changing the amount of addition (600mg/L, 900mg/L, 1200mg/L), subcooling (3.5℃, 5.5℃, 7.5℃) and pressure (4.90MPa, 6.0MPa, 7.31MPa). The experimental results show that AOT can effectively shorten the induction time under the three concentrations, and the higher the concentration, the smaller the induction time (0.21h at 1200mg/L), but the gas storage increases first and then decreases with the increase of the added amount. Finally, the optimum addition amount is 900mg/L, and the hydrate storage capacity is 55.76m3/m3. In addition, the higher the degree of subcooling and the higher the experimental pressure, the faster the hydrate nucleation rate, the shorter the induction time, and the higher the gas consumption rate. When the degree of subcooling is 7.5℃, the induction time is 0.31h, the gas consumption rate is 0.275mol/h, and the maximum gas storage is 63.95m3/m3. However, if the pressure is too high, hydrate will rapidly be formed at the gas-liquid interface in the kettle. The layer hinders the hydrates from continuing to form, resulting in a reduction of hydrate storage capacity to 46.84 m3/m3. Therefore, under the static system, reasonable selection of the concentration of the promoter and the driving force can significantly promote the formation of hydrate. © 2020, Chemical Industry Press. All right reserved.