Research progress in generation strengthening technology and method of natural gas hydrate

Exploitation and development of natural gas hydrate (NGH) have been included in the National 12th Five-Year Development Plan, withpotential strategic significance, considerable economic benefits and broad application prospects in natural gas transportation, desalination, carbon dioxide storage and other aspects. The key for successful application of NGH technology is to strengthen fast generation of NGH.Current research process of NGH generation strengthening technologies and methods are summarized. Physical methods include stirring, spraying, bubbling, external field and new technologies developed in recent years. Chemical methods are used to strengthen generatingNGH through the use of chemical promoters, including thermodynamic promoters, surfactants and new promoters developed in recent years.These methods can greatly improve NGH generation rate and storage density, but it is difficult to meet the requirements of NGH industrialapplication due to the higher costs. Therefore, a new spiral pipe flow NGH generation strengthening technology is proposed. It uses theform of NGH spiral flow in the pipeline to maximize the contact area of gas and liquid and accelerates heat removal when the gas hydrateis generated. On this basis, efficient composite promoter and hydrate separation device are provided, which can make the NGH technologycloser to industrial application.