1. Absorber progress
MICE-ISIS review of the liquid hydrogen system will be held in early January; guidance from Nominated Engineers on the imported absorber vessel and windows is required as an input to that review
AN/SW – find out and document the design, working and test pressures for the vessel and window assembly
Note that in the event of a catastrophic vacuum failure and violent liquid boil-off, the integrity of the pressure relief line(s) is the limiting factor, not the strength of the vessel or windows, which are not designed for that resultant pressure
SW – provide a simple schematic of the pressure relief tract, with linear distances and hydraulic diameters as part of review material
MC – ask David Jenkins for advice on speed of pressure build up resulting from violent liquid boil-off
AN/SW – revisit any calculations or tests already done by MICE on the above and try to converge
AN/SW/MC – arrange tour of MICE hardware when convenient for Mo prior to review
AN – make one last attempt to get the declaration of conformity from KEK
SW/AN – clear up any ambiguity over the possibly redundant annular volume around the vessel wall

2. Replacing hydride bed with bottle
Assumptions
Baseline plan is for 2 absorber fills
Outcome from R&D was that each bed charge would last 2-3 fills before needing topped up
Advantages
No risk of diminished bed capacity
Following jobs no longer necessary
Move pressure gauge
Replace cracked rubber tubing
Reinstate glycol line with drain
Purchase expansion tank
Replace hydrogen regulator
Reinstate auxiliary chiller
Purchase more glycol coolant
No icing/condensation collection inside gas panel
Quicker empty procedure
Disadvantages
Each fill operation needs 2 hydrogen bottles
Each empty procedure will result in lots of hydrogen gas being vented
Spare H2 bottles must be stored in case of emergency vent
New control sequences need to be written

3. Hydrogen fill procedure

4. System under vacuum after purge, H2 bottle connected

5. Hydrogen fills charging line up to control valve

6. Hydrogen liquefied through control valve loop

7. Bottle empty, switch valve to second bottle

8. Hydrogen fills charging line up to control valve

9. Absorber filling

10. Absorber now full

11. Vac out charging line

12. Pressurise with helium

13. Prepare for empty

14. Hydrogen empty

15. System ready after fill

16. Open N2-purged vent line

17. Use heater to boil off hydrogen

18. Absorber empty, open bypass valve

19. Pump out remaining hydrogen

20. System clear

21. Charging line design

22. Charging line design

23. Review