Reconstruction and operation of the helium purification system in the cryogenic system for EAST Tokamak

Abstract

Abstract EAST (Experimental Advanced Superconducting Tokamak) cryogenic system has participated in the physical experimental campaigns over 15 years since the first cool-down experiment in 2006. Some fault of the heat exchanger blocking due to the purification of gas helium has occurred several times during the cryogenic system’s operation since 2017, which caused the system warmed up to deal with the malfunction. Therefore, the helium gas purification system including the oil-removal system after the oil-injected screw compressors, the adsorbers inside the cold-box and two sets of external purifiers as well as the control system has been redesigned and reconstructed from 2019 to 2020, and put into operation in the 18th cool-down experiment of EAST cryogenic system at the beginning of 2021. The process flow of new helium purification system and the equipment parameters together with the reconstruction process will be presented in detail in this paper. Meanwhile, the commissioning operation results will be illustrated to show the purification performance good and the reconstruction successful.