Design and Fabrication of a Test Facility and Performance Measurement of 80 K Prototype Helium Purifier

Abstract

The Helium Refrigerator/Liquefier (HRL) plant being developed at IPR, needs helium purifier at temperature of 80 K. The LCPC (Large Scale Cryogenic Plant and Cryosystem) division was created in Apr-2012 primarily to create 1 kW class helium refrigerator-cum-liquefier (HRL) and peripheral cryo-components required for large scale R&D programmes like, fusion tokamaks and accelerators. In the twelveth 5-year plan, this division has taken up a project for development of helium plant of 2 kW cooling capacity at 4.5 K. It will also have provision to produce cooling capacity at temperature lower than 4 K. This HRL involves R&D for many cryogenic components along with bringing up industry infrastructure in the country. Though necessity all the precautions and impurity removing procedures are used, still in the process of gas transfer or by other processes the impurity level reaches to 500 ppm averaging about to 100 ppm. This impurities are consists of various gases like O2, N2, CO, H2O, CO2 etc. The purifier, based on charcoal adsorption concept, operating at 80 K is used for removal of Oxygen, Nitrogen and Argon. This has been designed by Institute for Plasma Research and different components are manufactured by different industries in India. The test facility has been set up to test 80 K helium purifier. There is provision to vary temperature, pressure, impurity concentration and type in the feed gas. Stress analysis of the existing piping system using CAEPIPE-Eval 8.00 has been done. Pressure drop test at different system pressures has been done to test the performance of the system and found working well within the permissible limits. Adsorption bed performance has also been conducted and it is found that the adsorption bed adsorbs 99.27% - 99.96% of impurities (Nitrogen).