Large-scale cryogenic refrigeration system is the only means of achieving a cryogenic environment for large scientific facilities. It is the indispensable core equipment for helium resource exploitation as well as for hydrogen energy application.  

With the ongoing support of the Ministry of Finance since 2010, the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences (TIPC-CAS) has developed a large-scale cryogenic refrigeration equipment with liquid helium temperature of 4.2K (-269°C) kilowatt level and superfluid helium temperature of 2K (-271°C) hundred-watt level via a decade-long scientific research project.  

It has broken through a series of key technologies and formed an R&D system with independent intellectual property, including high-speed turbine expander, cryogenic centrifugal compressor, oil-injection helium screw compressor, ultra-low leakage rate cryogenic heat exchanger, cryogenic valves, integration of refrigeration equipment, and so on. 

“Because of the successful implementation of the project, China has broken the monopoly of developed countries on large-scale cryogenic refrigeration technology below 20K temperature zones”, said Prof. GONG Linghui，the director of the project. 

The project has also created a development methodology of "research, application and tech-transformation". The hundred-watt large cryogenic refrigeration equipment have been successfully put into operation in related fields, such as helium extraction in Yanchi, Ningxia, the superconducting magnet test platform of Institute of High Energy Physics, CAS and nuclear fusion science device abroad, etc. More applications and technology transfer are being realized through the technology transformation company, i.e. Sinoscience Fullcryo. 

At the beginning of 2022, “the large-scale cryogenic refrigeration system from liquid helium to superfluid helium temperature zone” was awarded as one of the highlights of scientific and technological innovation achievements of CAS in 2021. 

In the future, TIPC will take actively “the open competition mechanism to select the best candidates” to launch new challenges to the larger cryogenic capacity research and application.