Effect of Stirring On CO2 Hydrate Formation

It is a challenge technique to capture and storage CO2 by hydrate crystallization. Applications still stayed in the laboratory stage because of complexities of the process, slow hydrate formation rates and costs. Therefore some promoting methods must be introduced during the hydrate formation process. It is an effective method to accelerate the CO2 hydrate formation by stirring. In order to increase the hydrate formation rate and decrease the energy consumption, the effect of different stirring times on CO2 hydrate formation was carried out experimentally with a high-pressure test cell. The results showed that the stirring could improve the CO2 gas dissolution rate effectively during the hydrate formation process. CO2 gas reached dissolution saturation in only three minutes under the condition of stirring rate 250r/min, while this process required about 100 minutes without stirring. In addition, it was found that stirring is extremely favorable for the hydrate formation when it occurs during the temperature cooling down process. With 40-munite stirring in the temperature cooling down process, the hydrate formation showed almost the same effect to that introduced by 200 minutes stirring, and the energy consumption was reduced.