ENCV LHCb Sci Fi Common chiller Martin Doubek

EN-CV: LHCb Sci. Fi Common chiller Martin Doubek September 25, 2017

Common chiller • Novec plant (pumps) • Sci. Fi • UT + Velo CO 2 plant 8 k. W 9. 4 k. W 7+4 k. W ~ 30 k. W Evaporation ~ -48°C Evaporation ~ -65°C 02. 05. 2017 2

UT+Velo cooled by direct expansion Evaporation temperature ~ -48°C (1 bar) Liquid pipe: copper ID 12 mm Vapor pipe: copper ID 38. 8 mm 13 bara Saturation: 26°C 15 bara These lines will be installed in YETS 2017/18 02. 05. 2017 3

Our Strategy • We select the technoglogy (refrigerants, compressors) • I have done preliminary sizing and component selection in order to get an idea about the size of the chiller. • We will define the arrangement of the chiller, external dimensions and position of input/outputs. Due to the space constrains and size of the transport lift and available space we have to split the chiller into several modules that can be transported separately. • The company selected in the tender process will carry out the final design, sizing and component selection based on our specifications. 3/7/2021 LHCb common chiller study 4

Refrigerant selection • The flammable refrigerants can be ruled out even though they can be used for very low temperatures. • The CO 2 solidifies at -56°C. There are only two options: • R 404 a with Two-Stage compression • R 23 -R 404 a or R 23 -R 134 a cascade 3/7/2021 LHCb common chiller study 5

Common chiller - Options R 404 a two stage • Two stage compression is needed to achieve low evaporation temperatures. • Relatively simple technology • Evaporation pressure well below atmosphere • Low temperature and power margin → see following slides Cascade system • • R 404 a – R 23 Possibly with screw compressors Larger system and more complex system Generous temperature and power margin 02. 05. 2017 6

Future of refrigerants Regulation (EU) No 517/2014 of The European Parliament and of The Council of (16 April 2014) From 2020 onwards: • Stationary refrigeration equipment, that contains HFCs with GWP of 2500 or more will not be permitted except equipment intended for application designed to cool products to temperatures below -50°C • HFC of very high GWP (>2500) will not be permitted in hermetically sealed equipment This regulation does not concern us directly, but it will impact price and availability of the R 404 a refrigerant in the future. In fact, the price is already increasing.

Bitzer 2 -stage R 404 a compressors Evaporation at -65°C Condensation limit 40°C 18 bara 02. 05. 2017 8

Bitzer 2 -stage compressors S 6 F - The most powerful single 2 -stage Bitzer compressor Evaporator duty [k. W] S 6 F Bitzer compressor performance Subcooler, Condensation 32°C, 5°C superheat 16 50 Hz 60 Hz 14 (70 Hz) 12 10 8 6 -80 -60 -40 Evaporation temperature [°C] 02. 05. 2017 -20 9

R 404 a saturation curve Pressure [bar] 1. 2 1 0. 8 0. 6 0. 4 0. 2 0 -75 -70 -65 -60 -55 -50 -45 Evaporation temperature [°C] 02. 05. 2017 -40 10

Note: ATLAS IBL Marco chillers The two-stage Bitzer R 404 a compressor are used in small chillers for ATLAS IBL 2 k. W @ -50°C The compressors will be used also in ATLAS and LHCB baby demos. ü We have some experience with this technology ü The Marco chillers have proven reliable, however, they operate the higher suction pressures than we need 3/7/2021 LHCb common chiller study 11

Alternatives to R 404 a Several low GWP alternatives for R 404 a are available: • Bitzer compressor are compatibile with the alternative low-GWP blends Condensation temp. • However, the low temperature operation envelope is limited probably due to higher discharge temperatures Evaporation temperature 3/7/2021 LHCb common chiller study 12

Alternatives to R 404 a The alternative refrigerants have significantly lower density which causes decrease of mass flow and cooling capacity: Cooling capacity [k. W] Compressor cooling capacity Full subcooling compressor: S 6 F-30 -2 Y 60 Hz 35 30 25 20 15 10 5 0 R 448 a R 404 a Condensing: 35°C Superheat: 5 K Reference temp: Dew point -70 3/7/2021 -60 -50 -40 Evaporation temperature [°C] LHCb common chiller study 13

Chiller concept: • Two modules each with 3 compressors (R 404 a Bitzer S 6 F) • Third module contains the condenser, receiver and Sci. Fi evaporator Module 1 Module 2 3 x compressor Bitzer SF 6 Module 3 Condenser Oil separators Liquid receiver Sci. Fi Evaporator (Novec) 3/7/2021 Thermosiphon commissioning 14

Concept: • The modules with compressors can work together with the same suction pressure • Each module can be switch between the UT+Velo or Sci. Fi • Only one module can cool all the system (UT+Velo and Sci. Fi) 3/7/2021 Thermosiphon commissioning 15

Concept: Sci. Fi UT+Velo 3/7/2021 Thermosiphon commissioning 16

Concept: Sci. Fi UT+Velo Valves Module 1 Module 2 3/7/2021 Thermosiphon commissioning 17

Module 1 is cooling the UT+Velo Module 2 is cooling the Sci. Fi Concept: Sci. Fi UT+Velo 1 compressor -50°C UT+Velo 3 compressors -65°C Sci. Fi 3/7/2021 Thermosiphon commissioning 18

One module is cooling all the UT+Velo and Sci. Fi is temperature is somewhat elevated Sci. Fi UT+Velo Maintenance 3 compressor -55°C Sci. Fi and UT+Velo 3/7/2021 Thermosiphon commissioning 19

See: G: DepartmentsENGroupsCVDetcoolProjects4. LHCb283. 0_Scifi2. Design_ChillerPID The detailed P&ID will be prepared by the company selected in the tender. We will specify the concept and requirements for certain valves and filters. P&ID 02. 05. 2017 20

First concept was to split the chiller into tow modules Lift size Unfortunately, the module does not fit the lift … and I really don’t think the module can be made any smaller. 3/7/2021 LHCb common chiller study 21

First draft of the modules: Module with one compressor module Suction connection Liquid and Hot gas connections 3/7/2021 LHCb common chiller study 22

Third module: Module with condenser and receiver Condenser Sci. Fi evaporator Receiver 3/7/2021 LHCb common chiller study 23

Possibility of future upgrade New module with additional compressor Manifolds can be easily extended 3/7/2021 LHCb common chiller study 24

All modules on the platform 3/7/2021 LHCb common chiller study 25

Chiller price estimate • Material price estimate 3/7/2021 125 000 EUR LHCb common chiller study 26

Schedule • Q 4 2017 chiller tender documentation • Q 1 2018 start of the tendering process • Q 2 2019 Installation of the chiller Following course of action leading to the installation of the chiller is foreseen: • Dismounting of the top platform • Upgrade of the RICH OT (lower platform) • Installation of the Sci. Fi cooling plant (lower platform) • Reinstallation of the top platform • Installation of the chiller 3/7/2021 LHCb common chiller study 27