1. ALICE Recovering the cryogenic system from major contamination

2. ALICE Energy Recovery Linac 2 x 1.3GHz 9 Cell SCRF Modules Operating temperature - 2K Pressure stability ± 0.1mbar

3. Cryogenics Plant Linde TCF50 Liquefier 1500 Litre Dewar (Wessington Cryogenics) Linde 2K Recouperator Leybold Ambient Pumps Transfer Lines manufactured by DEMACO

4. Breox Oil!!!! Historical oil contamination from Breox oil Formaldehyde Contamination Changed to CPI 4601-46 in 2009

5. DICC Installation

6. Contamination – Part 1

8. Fit Pressure Gauge

9. Contamination – Part 1 Adsorber replaced October 2013 Evidence of oil and carbon dust found on Hx E3110 Solvent flush performed on E3110

10. Contamination – Part 2 Feb 2014 Liquefier inoperable again!! Heated Nitrogen purge at 100°C Oil found from purge!!!! New adsorber now contaminated with oil?? Decided to remove the adsorber and replace with pipework.

11. Contamination – Part 2 March 2014 Liquefier opened to remove adsorber. Adsorber constructed from carbon pellets with a coarse mesh filter and Rockwool discs.

12. Contamination – Part 2

14. Visited Linde June 2014 X-ray tests of faulty adsorber inconclusive Adsorber cut open for inspection

15. Contamination – Part 2

16. Contamination – Part 3 July 2014 Capacity of the 2K system started to reduce Instrumentation failures 2K pumps trips due to low oil level Unable to maintain pressure stability so forced to shutdown for repair

17. Contamination – Part 3 Oil drained and Recouperator box cleaned. U-bend estimated to have contained at least 10 litres of oil. Still had persistent pressure drop in 4K box – Hydrocarbon from Compressor!!!!

18. Repair September 2014 started repairs. All oil contaminated pipework cleaned with Petroleum Ether.

19. Repair

20. Conclusions Find and fix your leaks. Test as much of your new equipment off-line. Service your equipment regularly. Don’t Rush!!!

21. Thanks! Hermann Herzog and his team from Linde Kryotechnik Wilhelm Vorbuchner – Cryvotech