Proximity Cryogenics PIDs Meeting Michel CHALIFOUR on behalf

Proximity Cryogenics P&IDs Meeting Michel CHALIFOUR (on behalf of the CERN Neutrino Cryogenic Group and David Montanari) Neutrino Platform General Bi-weekly Meeting March 3, 2016 Proto Dune-DP-NP 02

Outline • Project Requirements • Process and Instrument Diagram • Operation modes 2 03. 3. 16 Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02

Engineering parameters (from Detector Requirements) Mode Parameter Value Notes 1 GAr purge flow rate 88 m 3/hr From 1. 2 m/hr 2 Maximum cool-down rate TPC 40 K/hr 10 K/m 2 Maximum Delta T between any two points in the detector 50 K 3 LAr filling flow rate (*) 18 l/min Assuming 2 trucks/day (**) 4 Cryostatic heat leak 3. 0 k. W GAr boil-off (18 g/s) 4 Other heat loads (estimate) 5. 0 k. W Total estimate is ~ 8 k. W 4 LAr circulation (5 days turnover) 72 l/min (19 gpm) Nominal value (1 pump) 5 Emptying (w both LAr pumps) 144 l/min (38 gpm) Limited by size of tank/truck * Value might be limited by the pressure inside the LAr storage dewar. ** We need to contact the supplier to confirm availability of 2 trucks/day of LAr. Note: Noise, micro phonics and vibrations inside the LAr volume will be studied with an external pump configuration. 3 03. 3. 16 Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02

Cryogenic systems • Internal Cryogenics (not part of Neutrino Cryogenic group scope): - Inside the cryostat. - GAr/LAr distribution for cryostat purge, cool down, fill. - Interface control document needs to be created in-between proximity and internal cryogenics for physical and functional parameters (eg: temperature sensors/quantity and location for operation, Larg and Garg mass flow rate to cool down, interlock on Temperature, etc. . . ) • Proximity Cryogenics: - Circulate and purify LAr. - Achieve and maintain LAr purity. - Recondense and purify boil off GAr. • Infrastructure/External Cryogenics: Technical Specification/Tender will cover these 2 parts only - Receive Ar/N 2. - Transport GAr/LAr, GN 2/LN 2 to Proximity. - Vents. 4 03. 3. 16 Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02

Modes of operation 1) Piston Purge - Before starting piston purge, a purging and flushing of all argon circuits is mandatory - GAr is slowly flown from the bottom of the tank to push the impurities out from the top. 2) Cool down - 3) Filling - 4) Once the cryostat and TPC are cold, LAr is introduced in the cryostat. Normal operations - LAr is continuously purified by means of an external LAr pump (2 are installed for redundancy, but only one is in use). - Boil-off GAr is recondensed outside of the cryostat and purified before being reintroduced as LAr. 5) Emptying - 5 A mix of GAr and LAr is flown into sprayers to generate a mist of small liquid droplets that are moved around by another set of sprayers flowing GAr only. At the end of the operations (or if/when maintenance on the tank is needed), the tank is emptied and the LAr removed. 03. 3. 16 Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02

Storages tanks & Regeneration system / External Cryogenics LArg storage tank LN 2 storage tank Regeneration system 6 03. 3. 16 Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02

Filtering system / Proximity Cryogenics Purity monitor LArg filters GArg filter 7 03. 3. 16 Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02

Cryostat / Distribution system / Proximity & Internal Cryogenics LN 2 Phases Separator Condenser LArg circulating Pump-Optional? LArg Phases Separator 8 03. 3. 16 Needed? Michel CHALIFOUR P&IDs Meeting Proto Dune-DP-NP 02 LArg circulating pumps