TSTA compound cryopump

Journal Article · Wed Apr 01 04:00:00 EST 1981 · J. Vac. Sci. Technol.; (United States)

DOI:https://doi.org/10.1116/1.570854· OSTI ID:6403047

Batzer, T H; Patrick, R E; Call, W R

The Tritium System Test Assembly (TSTA), at the Los Alamos Scientific Laboratory, is intended to demonstrate realistic fuel supply and cleanup scenarios for future fusion reactors. The vacuum pumps must be capable of handling large quantities of reactor exhaust gases consisting largely of mixtures of hydrogen and helium isotopes. Cryocondensing pumps will not pump helium at 4.2 K; while cryosorption pumps using molecular sieves or charcoal have good helium pumping speed, the adsorbent clogs with condensed hydrogen while pumping mixtures of both. A solution to this problem is a compound design whereby the first stage condenses the hydrogen species and the second, or sorption, stage pumps the helium. The TSTA pump designed at Lawrence Livermore National Laboratory uses argon gas to cryotrap the helium in the helium--hydrogen mixture. The argon is sprayed directly onto the 4.2 K surface at a rate proportional to the helium flow rate, permitting continuous pumping of the helium--hydrogen mixtures in a single-stage pump. However, the possibility of differential desorption as a first stage in the TSTA gas separation cycle required the inclusion of a first-state hydrogen isotope condenser. The design, performance, and operating characteristics are discussed.

• Research Organization: University of California, Lawrence Livermore National Laboratory, Livermore, California 94550
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6403047
• Journal Information: J. Vac. Sci. Technol.; (United States), Journal Name: J. Vac. Sci. Technol.; (United States) Vol. 18:3; ISSN JVSTA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700209* -- Fusion Power Plant Technology-- Component Development & Materials Testing
CRYOPUMPS
DESIGN
DESORPTION
DISPERSIONS
EQUIPMENT
HELIUM ISOTOPES
HYDROGEN ISOTOPES
ISOTOPES
LABORATORY EQUIPMENT
MIXTURES
PUMPS
TESTING
THERMONUCLEAR REACTORS
ULTRAHIGH VACUUM
ULTRALOW TEMPERATURE
VACUUM PUMPS
VACUUM SYSTEMS