Performance of the Tritium Removal Systems at LLE 5SJUJVN GJMM TUBUJPO DMFBOVQ TZTUFN $SZPHFOJD FRVJQNFOU DMFBOVQ TZTUFN 4ISPVE SFUSBDUPS 5BSHFU DIBNCFS 5SJUJVN GBDJMJUZ --& USJUJVN FRVJQNFOU 1FSNFBUJPO DSZPTUBU %5 DPNQSFTTPS 5BSHFU DIBNCFS USJUJVN SFNPWBM TZTUFN.PWJOH DSZPTUBU 5SBOTGFS DBSU G. Wainwright University of Rochester Laboratory for Laser Energetics 17th Target Fabrication Meeting San Diego, CA 1 5 October 2006
Contributors R. Janezic, W. T. Shmayda, D. R. Harding, L. D. Lund, P. Regan, and G. Wainwright University of Rochester Laboratory for Laser Energetics A. Nobile Los Alamos National Laboratory
Summary The tritium removal systems have shown excellent efficiencies and robustness for DT operations at OMEGA Each fill requires processing of 10,000 Ci; produces four targets at 0.25 Ci per target; minimal losses to equipment (<3 Ci). Fuel is recovered back to the U-bed within measurement capability (± 0.3%) The largest leak observed from primary to secondary containment <1 Ci The tritium facility exhaust-stack levels are ~20 mci/week and the target chamber exhaust-stack levels are ~16 mci/week The total exposure to LLE staff from tritium operations is 0.007 man-rem Stack emissions after five 55% tritium deuterium fill operations and six imploded targets are <250 mci T2306
Overview of tritium handling during cryogenic-dt-filling operations at LLE Review the Tritium Removal Systems at LLE Summarize the performance of the TRS Trends in tritium stack concentrations in 2005/2006 Typical performance analysis of one TRS subsystem Decontamination of MCTC Wrap up T2305
Tritium facilty layout G6175
LLE employs four tritium removal systems to support tritium target filling and target implosions Tritium Fill Station (TFS) Cleanup System online since 1996 closed-loop system for the glovebox and effluent from primary piping Tritium Scrubber (OMEGA Cryopumps) online since 1996 intercepts tritium from OMEGA cryopump regenerations Cryogenic equipment Tritium Removal System (TRS) online since 2004 handles process streams to ~1 kci/m 3 six independent subsystems to handle air and helium gas streams Target Chamber-Tritium Removal System (TC-TRS) online since 2004 also services decontamination of MCTC s T2307
Tritium is captured from each process and inert containment stream with getters TFS functions store tritium remove helium-3 from DT fuel remove residual tritium from process loop assay tritium permeation-fill gas targets (<50 bar) provide fail-safe recovery of tritium transfer DT to DTHPS to fill cryo targets E13735
Elemental tritium hydriding by ZrFe alloy is the heart of the tritium removal system E11365b Drier removes HTO Ni cracks organics ZrFe absorbs HT
Cryo equipment TRS G6187
Target chamber TRS G6264
Routine tritium evolution from process equipment during a permeation fill cycle is <3 Ci Examples: ~10 mci leaks into the secondary containment during the highpressure (1000 atm) fill ramp (through valve packing) ~1 Ci released to the cryostat when the permeation cell is first opened to remove a target ~1 Ci comes from the target rack outgassing ~4 mci comes from decontaminating the vacuum interspace between the FTS and the Moving Cryostat Transport Cart (MCTC) ~100 mci from decontaminating MCTC s T2310
Emission from the tritium lab increased to an average of 22 mci/week with the introduction of DT-filling operations T2308
The target chamber TC-TRS maintains exhauststack emissions below 80 mci/week T2309
MCTC decontamination requires ~48 h to reduce airborne activity to a safe level (<10 nci/m 3 ) Tritium exposure: 2 target transfer 100 mci 2 targets 240 mci each Up to 50 decontamination (pump/air vent) cycles (automated procedure) 2 locations exhibited surface contamination >1,000,000 dpm/100 cm 2 (line of sight to target implosion) majority <1,000 dpm/100 cm 2 T2315
Response of TC-TRS to MCTC #3 decontamonation following cryo shot 2037-559 T2316
Summary/Conclusions The tritium removal systems have shown excellent efficiencies and robustness for DT operations at OMEGA Each fill requires processing of 10,000 Ci; produces four targets at 0.25 Ci per target; minimal losses to equipment (<3 Ci). Fuel is recovered back to the U-bed within measurement capability (± 0.3%) The largest leak observed from primary to secondary containment <1 Ci The tritium facility exhaust-stack levels are ~20 mci/week and the target chamber exhaust-stack levels are ~16 mci/week The total exposure to LLE staff from tritium operations is 0.007 man-rem Stack emissions after five 55% tritium deuterium fill operations and six imploded targets are <250 mci T2306