Helium recapture and reliquefier system for Dynamic Nuclear Polarization at UNH

Author : Chhetra Lama

Abstract :This talk concerns the installation of a new helium recapture and reliquefaction system, consisting of a gas bag, manifold, cooling chiller, purifier, high pressure compressor and cylinder banks, in the dynamic nuclear polarized target lab at University of New Hampshire. This new system has the capability to improve the efficiency of target polarizations runs by recycling our cryogenic helium which would otherwise be lost during polarization operations. Our helium liquefier is rated to 40 L/Day under normal full-capacity operations with 800L capacity. I will explain the initial installation process followed by a discussion of the challenges with installation, including issues of impurities which appeared during the initial operation of the system. Then I will discuss how we overcome these difficulties. Finally, I will discuss the function of the system during normal operation and the present situation of the helium recapture and reliquification processing in our lab.

Keywords :Helium recapture, helium reliquefaction, cryogenic helium, polarized target lab, gas recovery system, helium liquefier, dynamic nuclear polarization, impurity removal, cryogenic engineering, sustainable lab operations, helium recycling, high-pressure compressor, cooling chiller, manifold system, liquefaction efficiency.

Conference Name :International Conference on Applied and Practical Sciences (ICAPPRSC-25)

Conference Place Kathmandu, Nepal

Conference Date 20th Jan 2025