Application, development and future of helium compressor in large-scale cryogenic engineering

Abstract The efficiency of large-scale cryogenic equipment is very important. Efficient helium compression on more large scale will be one of the major challenges in the future. Helium compressors have experienced the evolution process of pistons and screws in helium liquefaction technology. Oil-injection screw compressor skillfully uses the sealing effect and atomization cooling effect of oil film to solve the technical problems caused by easy leakage of small molecular weight gas and high compression heat of helium gas respectively. In order to improve the compression efficiency of helium gas, two profiles of the screw rotor were continuously optimized according to different working conditions and developed into the latest asymmetric streamline. In order to cooperate with the application of oil injection screw compressor, oil-gas separation and the ppb level high-precision huge oil removal system are also a necessary supporting technology. With the accumulation of running time, it was difficult to avoid the accumulation of oil in cryogenic components, which would lead to engineering accidents. In order to completely solve the ultimate problem of oil pollution, centrifugal compression technology based on high-speed magnetic bearing is also expected to become the future development trend.