Technical Improvement and Application of Liquid Nitrogen Freezing System for Temporary Plugging
Liquid nitrogen freezing technology is a highly advantageous wellhead disposal technology.In order to improve the efficiency of wellhead disposal in well control rescue,this article summarizes the technology factors that affect the freezing efficiency of the freezing system with liquid nitrogen,and uses the ANSYS-Fluent fluid simulation software to numerically simulate and analyze the three most promising parameters,namely the number of inlets,the inlet diameter,and the freezer box diameter,based on the characteristics of equipment technology.It can be concluded that:increasing the number of inlets appropriately can effectively improve the freezing efficien-cy;increasing the inlet diameter has a certain benefits in improving the freezing efficiency;reducing the freezer box diameter mainly improves the local freezing efficiency,but has little impact on improving the overall freezing efficiency of the drill pipe.Based on the conclusions obtained,a refrigerant injection tube was designed and manu-factured,which increased the freezing efficiency of the equipment by about 40%.
temporary plugging by freezingwell control emergencygas inletsfeezer box