1. Large-capacity Helium refrigeration : from state-of-the-art towards FCC reference solutions Francois Millet – March 2015

2. Large-capacity helium refrigeration – FCC week 2015 Contents Introduction FCC requirements & constraints From the state-of-the-art towards FCC  Refrigeration scheme & components  Cooling capacity  Cooling architecture Conclusion 2

3. Large-capacity helium refrigeration – FCC week 2015 Introduction Main FCC cryogenic challenges : -towards 1 MW @ 4.5 K (> 200 MW of electrical power consumption) -mainly dynamic heat loads at 40-60 K (Synchrotron radiation) -Large-scale superfluid helium refrigeration down to 1,6 K (*) (*) see presentation “Study of a magnetic refrigeration stage” => Study & Developments of Larger Refrigerators with high reliability and efficiency (50-100 kW @ 4.5 K range including 5-10 kW @ 1.8 K)

4. Large-capacity helium refrigeration – FCC week 2015  Analysis of FCC requirements & constraints  Review of the State-Of-the-Art  Identification of present process and component limits  Development of new technologies or architectures in collaboration with CERN & major cryoplant industries => Definition of FCC reference solutions CEA study roadmap Study & Developments of Larger Refrigerators (40-100 kW @ 4.5 K range including 5-10 kW @ 1.8 K)

5. Large-capacity helium refrigeration – FCC week 2015 Contents Introduction FCC requirements & constraints From the state-of-the-art towards FCC  Refrigeration scheme & components  Cooling capacity  Cooling architecture Conclusion 5

6. Large-capacity helium refrigeration – FCC week 2015 FCC-hh cryogenic layout Cryopla nt L Arc+DS [km] L distribution [km] 2 x 4 = 82 x 4.7 = 9.4 8.4 Cryopla nt L Arc+DS [km] L distribution [km] 44.7 4.45.1 44 4.46.5 10 cryoplants 6 technical sites 20 cryoplants 10 technical sites No cryoplant redundancy at Point A and G No distribution in ESS L. Tavian / CERN => 12 sectors to be cooled with different lengths and heat loads

7. Large-capacity helium refrigeration – FCC week 2015 Rough FCC-hh heat loads estimate 7 L. Tavian / CERN + cooling for HTS current leads from 40 K to 300 K Temperature level LHC [W/m]FCC-hh [W/m] 50-75 K4.5-20 K1.9 K40-60 K1.9 K Static heat inleaks CM supporting system1.50.102.00.13 Radiative insulation0.110.13 Thermal shield2.73.1 Feedthrough & vac. barrier0.20.10.20.1 Distribution 3.20.10.0240.1 Total static7.6 0.1 0.3 9.3 0.46 Dynamic heat loads Synchrotron radiation0.33  57 (88)0.2 Image current0.362.7 (2.9) Resistive heating0.10.3 (0.4) Beam-gas scattering 0.050.45 Total dynamic0.70.1564 (95)0.95 (1.05) Total7.60.80.4573 (104) 1.4 (1.5) (): Value in brackets for 80-km FCC-hh

8. Large-capacity helium refrigeration – FCC week 2015 FCC-hh main heat loads  SC Magnets & RF cavities at 1.9 K  Beam screens at 40-60 K  Thermal Shield at 40-60 K  HTS Current leads between 40-300 K FCC–hh cooling requirements 1.8 K bath 300 K to 4.5 K refrigeration SC Magnets + Cavities HTS Current Leads 40 K 60 K 300 K 4.5 K 42 K Assumptions : w/o over-capacity margin / integral CC & CC efficiency = 70% Beam Screen 1 MW eq @ 4.5 K (> 200 MW of Elec. Power) Thermal Shield

9. Large-capacity helium refrigeration – FCC week 2015 Contents Introduction FCC requirements & constraints From the state-of-the-art towards FCC  Refrigeration scheme & components  Cooling capacity  Cooling architecture Conclusion 9

10. Large-capacity helium refrigeration – FCC week 2015 Conventional refrigeration scheme Warm Compression System Compressor Gas cooling Oil removal Cold Box Heat exchangers Turbines Valves Two phase vessel Liquid helium supply Principle scheme of a simple refrigerator ORS U.Wagner/ CERN

11. Large-capacity helium refrigeration – FCC week 2015 Refrigeration technology – Main components Warm Compressor System Cold Box Linde / Air Liquide

12. Large-capacity helium refrigeration – FCC week 2015 Present large-scale He refrigerators & Liquefiers U.Wagner / CERN F.Andrieux / ALAT LHC 4.5 K Refrigerators 18 kWeq @4.5K Qatar Helium Recovery Unit 20 tons/day - 24 kWeq @4.5K Under construction ITER He Plant 3x25 kWeq @4.5K 3 modules in // + ITER 80 K Loop 2x20 kWeq @4.5K 2 modules in //

13. Large-capacity helium refrigeration – FCC week 2015 FCC cryoplant cooling capacity He plant cooling capacity for FCC ? Larger cryoplants (up to factor 4) or modules in // (2 to 4 modules)

14. Large-capacity helium refrigeration – FCC week 2015 LHC architecture  One 18kW eq @ 4.5 K Refrigerator per sector to provide all cooling capacity for one LHC sector C: 4.5 K; 3.0 bar B: 3.5 K; 15 mbar D: 20 K; 1.3 bar F: 75 K; 18.0 bar E: 50 K; 18.5 bar Warm recovery Warm Compressor Station 4.5 K Refrigerator Cold Box 1.8 K Refrigeration Unit Warm Compressor Station Cold Compressor Box Interconnection Box U.Wagner/ CERN SC Magnets HTS Current Leads Beam Screen Thermal Shield

15. Large-capacity helium refrigeration – FCC week 2015 ITER architecture E.Monneret/ITER  One He plant for ITER heat loads < 80 K SC magnets, HTS current leads, cryopumps  One 80 K loop for ITER heat loads > 80 K Thermal shields, precooling of He plant

16. Large-capacity helium refrigeration – FCC week 2015 FCC-hh cryoplant architecture Cryoplant architecture for FCC ?  LHC-like design = One cryoplant per sector for all cooling needs of the FCC machine SC magnets & RF cavities, HTS current leads, beam screens, thermal shields  ITER-like design = Two cryoplants (4.5K & 40K) per sector for separated cooling needs of the FCC machine 4.5K plant for SC magnets & RF cavities 40K plant for beam screens, thermal shields, HTS current leads, He plant precooling (see TU-Dresden presentation) Low number of plants & interfaces Limited efficiency optimisation Possible efficiency optimisation Large number of plants & interfaces

17. Large-capacity helium refrigeration – FCC week 2015 Contents Introduction FCC requirements & constraints From the state-of-the-art towards FCC  Refrigeration scheme & components  Cooling capacity  Cooling architecture Conclusion 17

18. Large-capacity helium refrigeration – FCC week 2015 Conclusion  Large helium refrigeration capacity required for FCC  Towards 1 MW eq.@ 4.5K for FCC-hh / 100 km @ 1.8 K  Mainly dynamic heat loads around 50 K  ~50% of total kW eq @ 4.5 K heat loads  On-going works to define reference solutions for FCC based on :  FCC cryogenic requirements and constraints,  Review of the State-Of-The-Art and present limitations,  Study of new architectures and technologies with industries and partners (*). 18 (*) CEA study with strong interaction with CERN and TU-Dresden as well as major cryoplant industries

19. Large-capacity helium refrigeration – FCC week 2015 Thanks you for your attention Any question ? 19