Liquid Helium Technologies at the Cryogenic Complex of the Heavy Ion Collider NICA

Abstract

Since 1992, the largest Russian cryogenic helium complex of the superconducting accelerator Nuclotron with the cooling capacity of 4000 W at 4.5 K has been operating at the Joint Institute for Nuclear Research in Dubna. The construction of this high-efficient cryogenic system included a large number of technical ideas that had never been applied before in the world. The helium complex of the Nuclotron has become the most advanced and largest Russian liquid helium plant consisting of two KGU–1600/4.5 units, which are capable to operate for a common collector of the liquid helium delivery to the consumer and provide the total capacity of 1000 l/h. In 1992 its use allowed one to begin for the first time the export of liquid helium by means of 40 m³ auto transport containers. The annual level of export deliveries reached 1 million liters. In the near future it is planned to construct a new accelerator complex comprising beside the Nuclotron a superconducting booster and collider to provide collisions of high-intensity beams of heavy ions up to gold Au⁺⁷⁹. The cryogenic system of this megaproject includes the latest Russian developments: helium liquefiers with the capacity of 1100 l/h and screw helium compressor aggregates with the outlet pressure of 3 MPa and capacity of 6600 Nm³/h. The assembling and tests of pilot units are being carried out at present. This equipment being commissioned to mass production may lay the foundation for the technology of industrial liquefaction of helium for the development of new deposits in Eastern Siberia.