Research progress on the induction period of hydrate formation

Carbon dioxide sequestration and hydrogen storage by hydrate method and natural gas hydrate (NGH) extraction are important means to achieve fossil energy transition and clean energy utilization. The induction period (IP) of hydrate formation is an important parameter in the process of hydrate formation. Shortening the IP of carbon dioxide and hydrogen hydrate formation is of great significance for realizing carbon dioxide sequestration and hydrogen storage. Extending the IP of NGH in subsea pipelines is significant for flow assurance. This paper comprehensively summarizes the determination methods of hydrate IPs, analyzes the effects of guest molecule composition, temperature and pressure, external disturbances, memory effects, water cut, crude oil components, and chemical and physical additives on hydrate formation IPs, and reviews current models of hydrate formation IPs. In conclusion, the current variety of methods for determining the IP of hydrate formation and the low accuracy of the models require further research to improve the scientific validity and accuracy. There are many factors affecting the hydrate IP, but the synergistic influence law under different factors still needs further investigation. In the future, it will be necessary to reveal the hydrate nucleation process from a microscopic point of view with the help of high-precision instruments and molecular simulations under the action of multiple complex influencing factors. To develop more precise determination methods for hydrate IPs and establish predictive models with improved universality and accuracy.