1. Hydrogen Pre-Operation Safety Review 4 th October 2011 Results from Helium Commissioning M Hills

2. Hydrogen Pre-Operation Safety Review 4 th October 2011 Outline 1.Test Set-Up 2.Purge Test 3.Cool-down 4.Absorber Fill 5.Warm-up 6.Conclusions 2

3. Hydrogen Pre-Operation Safety Review 4 th October 2011 Test Set-Up 1 Gas Panel: –In “position 3” and connected to hall air supply –All wiring installed as it will be for the R&D –Transfer line jacket in place, although no nitrogen purge Cryocooler: –Compressor in final MICE running location and connected to hall cooling water supply –Lines stored in reel as they will be for the AFC Helium Supply: –System filled from BIP grade helium pack inside the hall Control System: –Wiring in place to allow PLC logging of temperatures, pressures and levels –Remote control of purge pump 33

4. Hydrogen Pre-Operation Safety Review 4 th October 2011 Test Set-Up 2 Vacuum System: –Temporary pumping rig used for cryostat vacuum –System purge pump located on south mezzanine instead of external vacuum enclosure Cryostat: –All temperature sensors operational –Could only read one level sensor at a time for first part of test 4

5. Hydrogen Pre-Operation Safety Review 4 th October 2011 5 Purge Test –Automated sequence which purges the entire system 3 times prior to operation –Demonstrates: –PLC programming –Pressure and temperature instrumentation –Purge pump operation 5

6. Hydrogen Pre-Operation Safety Review 4 th October 2011 Cool-down 6 N2 pre-cool Cryostat reaches base temperature Warm N2 purge

7. Hydrogen Pre-Operation Safety Review 4 th October 2011 7 Level Sensors LS1 LS2 LS3 LS3a LS3b LS3c LS3… LS1a LS1b LS1c LS1…

8. Hydrogen Pre-Operation Safety Review 4 th October 2011 Testing Modes i.Manual top-up: –Fill the system to ~1.4bara the seal off –Let the pressure drop –Top-up just before pressure drops below 1bara ii.Automatic top-up: –PID control on CV04 to keep the pressure ~1.2bara 8

9. Hydrogen Pre-Operation Safety Review 4 th October 2011 LS3 History (manual) 9

10. Hydrogen Pre-Operation Safety Review 4 th October 2011 LS3 response to manual fill 10 In liquid Possibly in liquid? Not in liquid

11. Hydrogen Pre-Operation Safety Review 4 th October 2011 LS3 History (automatic top-up) 11 In liquidLiquid covers LS3c In gas

12. Hydrogen Pre-Operation Safety Review 4 th October 2011 LS1 History (automatic top-up) 12 In liquid Liquid covers LS1e In gas

13. Hydrogen Pre-Operation Safety Review 4 th October 2011 LS1 Detail (automatic filling) 13 Almost full?

14. Hydrogen Pre-Operation Safety Review 4 th October 2011 LS3 Detail (automatic filling) 14 In liquid Partially covered? In gas (vent line)

15. Hydrogen Pre-Operation Safety Review 4 th October 2011 Warm-Up –Heaters operated manually at 10 & 20% duty to boil off liquid –Enthalpy of vapourisation for H2 is over 5x that for helium, so it should be easier to control the warm up sequence –PID control of CV04 allows the system to maintain a stable pressure as it returns to room temperature 15 PRV opening

16. Hydrogen Pre-Operation Safety Review 4 th October 2011 Heater response in LS1 16 Initial boil-off Complete boil-off PID control of CV04

17. Hydrogen Pre-Operation Safety Review 4 th October 2011 Conclusions –The system purge has been tested and run as a fully automatic sequence –A complete sequence of cool-down, absorber fill, and warm-up has been tested –The pressure relief system have been shown to be effective at controlling the system pressure (even when the control system isn’t) –Level sensors can be used to indicate how much liquid is in the absorber pot –May need to use manual control of CV04 at to see same effect with hydrogen –Will also be affected by the desorption rate of the hydride bed  The system has been shown to perform as required with helium 17