1. SOFREGAZ LAGUNA-LBNO PROJECT LIQUID ARGON PRE-MEETING PROCESS FACILITIES (FILLING FACILITIES, BOG HANDLING, FILTRATION UNIT) Geneva – CERN – 22 nd February 2012

2. AGENDA 2LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON TANK DESIGN CONDITIONS 1.LIQUID ARGON TANK DESIGN CONDITIONS 2.LIQUID ARGON SOURCING & PROCUREMENT 3.ABOVE GROUND RECEPTION FACILITIESLIQUID ARGON FILLING LINE BOIL OFF RECONDENSATION UNITS 4.LIQUID ARGON CIRCULATION & FILTRATION 5.AIR PURGE AND COOLING DOWN 6.CAVERN COOLING 7.POSSIBLE PROBLEMS WITH LEAKS 8.ELECTRICITY 9.AIR PURGE AND

3. LIQUID ARGON TANK DESIGN CONDITIONS: Operating Pressure 3LAGUNA-LBNO LAr-Process Facilities The basic assumption is to operate a fixed absolute pressure in the LAr tank. So in order to have at any time an internal pressure above ambient pressure in the cavern we have to take into account the ambient pressure variation at ground level and the head of air column from ground to bottom. We use data giving pressure variation during three years at OULUSALO located 140 km north of PYHASALMI ( http://timetric.com/index/atmospheric-pressure-oulunsalo-oulu-province- efou-metar/ ) If we assume that the pressure in PYHASALMI is the same than in OULUSALO we can calculate the pressure variation in the bottom of the mine where the LAr tank is expected to be installed (either at -900 m or at -1,400 m depth from ground level). http://timetric.com/index/atmospheric-pressure-oulunsalo-oulu-province- efou-metar/ Depth below ground (m) Depth below sea level (m) Multiplying factor (ref. Sea level pressure) Minimum pressure (mbar) Maximum pressure (mbar) Pressure range (mbar) Sea level0967105790 Minus 900 Minus 750 1.0941058115698 Minus 1,400 Minus 1,250 1.16011221226104

4. LIQUID ARGON TANK DESIGN CONDITIONS: Operating Pressure 4LAGUNA-LBNO LAr-Process Facilities

5. 5 Maximum decrease of pressure over a fixed number of hours is summarized in the here below table This pressure drop corresponds to around minus 0.4°C in the equilibrium temperature, well more than the maximum variation of the temperature in the tank at constant pressure ( 0.010°C). So if all the liquid is concerned by the temperature drop, the vaporization rate will reach 0.32% of its mass. As boil off is 0.07% /day, this additional flow would be quite 10 times the boil off flow. In order to minimize effect of vaporization thus convection currents in the liquid and also the size of boil off condensation unit, a constant pressure is retained by scientific team. We propose to operate at LIQUID ARGON TANK DESIGN CONDITIONS: Operating Pressure Depth below ground (m) Ambient pressure maximum variation range 3 years72 hours48 hours24 hours12 hours6 hours Sea level903531252119 Minus 900983833272321 Minus 1,4001044136292422

6. 6LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON TANK DESIGN CONDITIONS: Operating Pressure Depth below ground (m) Depth below sea level (m) Minimum ambient pressure (mbar) Maximum ambient pressure (mbar) Absolute operating pressure of LAr tank= Maximum ambient Pressure + 10 mbar (mbar) Maximum differential pressure Operating Range (mbarg) MeasuredDesignMeasuredDesign Minus 900 Minus 750 1058104811561166 118 Minus 1,400 Minus 1,250 1122111212261236 124 Taking 10 mbar security value for both maximum and minimum ambient pressure at LAr level, we obtain the following figures: So we propose following max operating differential pressure for LAr tank design : 118 mbarg for -900m and124 mbarg for -1400m

7. 7LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON TANK DESIGN CONDITIONS: Boil Off rate The following LAr tank boil-off rates have been assumed: Tank capacity (in ktons) 2050100 Boil-Off rate (% vaporized / day) 0.090.070.06

8. LIQUID ARGON SOURCING & PROCUREMENT 8LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON PRODUCTION CAPACITY  FOR THE WORLD NO COHERENT FIGURE FOUND ON ARGON PRODUCTION  OXYGEN PRODUCTION IN 2006 WAS 1.2MTPD HALF OF IT FOR STEEL  ASSUMING THE SAME RATIO AS IN EUROPE, 90% OF OXYGEN PLANTS PRODUCING ARGON AND 90% EFFICIENCY  WORLD PRODUCTION WOULD BE 60,000TPD.  THIS FIGURE SEEMS TOO HIGH, PROBABLY MOST OXYGEN PRODUCING PLANTS DON T PRODUCE ARGON.

9. LIQUID ARGON SOURCING & PROCUREMENT 9LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON PRODUCTION CAPACITY IN GEOGRAPHIC EUROPE INCLUDING WEST RUSSIA:  220 AIR SEPARATION PLANTS  4,000 TONS/DAY ARGON PEAK PRODUCTION  3,500 TONS /DAY TAKEN BY CUSTOMERS  AROUND 500 TONS/DAY AVAILABLE COST AROUND 0.6€/kg WITHOUT TRANSPORTATION, FOR FLARE PROJECT PRICE FROM PRAXAIR WAS 0.6$ IN JANUARY 2004

10. LIQUID ARGON SOURCING & PROCUREMENT: Commercial Liquid Argon Specifications 10LAGUNA-LBNO LAr-Process Facilities AIR LIQUIDE:

11. LIQUID ARGON SOURCING & PROCUREMENT: Commercial Liquid Argon Specifications 11LAGUNA-LBNO LAr-Process Facilities AIR PRODUCT: Product Grade Component Industrial or Commercial High Purity (H.P.) Ultra High Purity (U.H.P.) Argon Purity99.9999.99599.999 Oxygen Content< 10 ppm< 5 ppm< 3 ppm Dew Point- 65 °C- 68 °C- 70 °C PRAXAIR:

12. LIQUID ARGON SOURCING & PROCUREMENT: Commercial Liquid Argon Specifications 12LAGUNA-LBNO LAr-Process Facilities ASSUMED COMPOSITION FOR DESIGN: SPECIFICATIONCONTENT Oxygen content<5 ppm molar Water content<1 ppm molar Hydrocarbons<0.5 ppm molar Purity> 99.999 %

13. LIQUID ARGON SOURCING & PROCUREMENT: Transportation mode 13LAGUNA-LBNO LAr-Process Facilities Argon available in Europe only, seems enough to fill a LAr tank within a reasonable duration, with 500TPD it will be :  66 days for the 33,000 tons LAr for the 20kton  146 days for the 73,000 tons LAr for the 50kton  280 days for the 140,000 tons LAr for the 100kton Will come from part of the 220 sources of liquid argon in Europe, say 100 sources, with 500TPD each source will send 5TPD. This quantity is not enough for delivery by complete train, with minimum 500 tons argon. Only Russia which has the same rail width than Finland could supply by railway,if large quantity of argon are available on some large plant,such as VOLOGDA 800km from PYHASALMI and which will produce 3,000TPD oxygen thus around 150TPD argon.

14. 14LAGUNA-LBNO LAr-Process Facilities But if part of Argon come by railway, capacity to unload rapidly complete train must be available, thus many unloading areas for the rail-tankers and a large buffer tank. Location of delivery will be the ore loading station which is far from the point vertically above the tank so horizontal pipeline must be added. Without any information on possibility to have on large plant in Russia supplying argon by complete train and considering that argon will be supplied from many small sources rather than a few large sources, we retained transport by cryogenic semi trailer and cryogenic 6m tank containers. LIQUID ARGON SOURCING & PROCUREMENT: Transportation mode

15. LIQUID ARGON SOURCING & PROCUREMENT: Liquid Argon Transportation mode 15LAGUNA-LBNO LAr-Process Facilities Capacity of 6 m container is 26 tons of argon, capacity of semi trailer 18 tons of argon.

16. ABOVE GROUND RECEPTION FACILITIES 16LAGUNA-LBNO LAr-Process Facilities CONDITIONS OF ARGON ARRIVING IN PYHASALMI  Mean flow: 500TPD or 360m3/day  Mode of transportation : around 28 semi trailers or containers on trucks per day.  Season, not in winter as roads are covered with snow and short daylight.  No arrival by night?? unloading facilities working in 2 shifts of 8 hour, in summer end of spring and beginning of autumn.  Max pressure of container 3.8 barg corresponding to 11 days travel with 5% vapor space.

17. ABOVE GROUND RECEPTION FACILITIES: Sizing of Above ground Buffer Tank 17LAGUNA-LBNO LAr-Process Facilities Operating pressure of standard tanks are from 5.6barg to 10.7barg and 14 barg. 5.6 barg is 1.4 bar over maximum pressure of argon from truck. Temperature (at @5.6 barg) of liquid/vapor equilibrium of minus163.4°C Arrival of heat at the rate of 38kW sufficient to take care of inflow of heat with the pumps, through the flexible hoses, the piping and the buffer tank itself (around 0.11% /day or 1kW). Capacity, to take care of the night without arrival of argon from trucks and some reserve will the max standard size close to 1 day or 300m3. Size of standard tank is diameter 3.6m length 38m.

18. ABOVE GROUND RECEPTION FACILITIES: Sizing of Above ground Buffer Tank 18LAGUNA-LBNO LAr-Process Facilities

19. LIQUID ARGON FILLING LINE 19LAGUNA-LBNO LAr-Process Facilities Mean flow of incoming argon is 500TPD, buffer tank at surface cater for flow variation with the irregularities with the arrival of trucks. Flow to the bottom cavern is constant, value is 15m3/h. With 100% pressure drop corresponding to a vertical pipe inner diameter of pipe is 31mm and full flow speed 5m/s So we take 1 ¼” Stainless Steel pipe ( 42.2mm external diameter ) with standard thickness 4.85mm ( schedule 80) and inner diameter 32.5mm.  Weight of the pipe is 5.61kg/m  Weight of 50mm half shells 80kg/m3 polyurethane insulation is 1.15kg/m.  Weight of 1mm thick butyl aluminum sheet as vapor barrier on the insulation is 0.44kg/m

20. LIQUID ARGON FILLING LINE 20LAGUNA-LBNO LAr-Process Facilities Weight of the LAr in the pipe which is transmitted to the pipe as friction of liquid argon is equal to weight is 1.16kg.  Total empty pipe weight is 7.20kg/m  Total weight of pipe in operation is 8.36kg/m For 900m long vertical pipe, weight is 6.48tons for empty pipe and 7.52tons with pipe full of LAr:  Longitudinal traction stress in hanging Stainless Steel pipe is 63,568 N/569mm2 for empty pipe.  That is 11.1hbar for empty pipe  And 13.0hbar for pipe full of liquid argon.  Yield strength at 0.2% of 304 steel is 29hbar at ambient and 48hbar at liquid argon temperature. Stress of hanged pipeline is :  38% of yield strength at ambient.  27% of yield strength in operation. For 1,400 m long vertical pipe, results are also acceptable.

21. LIQUID ARGON FILLING LINE 21LAGUNA-LBNO LAr-Process Facilities So vertical hanged pipeline is possible, welded, insulated vertically from the surface and let down in a borehole without requirement of any intermediate access. Although with 4.85mm wall thickness and 60% of YS radial stress pipeline can take pressure of: 2 x 4.85 x 0.875 x 0.6 x 4800/42.2=579bar Pipeline will work at the liquid /vapour equilibrium pressure corresponding to temperature of fluid in the pipeline. To achieve that at the bottom of pipeline a tank with level of liquid argon controlled such a way that gas volume is more than volume in the pipeline 0.75m3.

22. LIQUID ARGON FILLING LINE 22LAGUNA-LBNO LAr-Process Facilities Stop of flow in the pipeline will be by a valve at surface,in this case liquid argon in the pipe will go to the available volume in the tank at bottom. Flow reduction will be by a valve at surface buffer tank outlet, flow in the pipe will be torrential when flow is reduced below maximum capacity. With thickness 50mm polyurethane, heat inflow in the pipeline will be : 2 x 3.14 x 0.025 x (15—185)/(ln((42+2 x 50)/42) =26kCal/m/h or 30W/m. So 27kW for the pipeline. Energy of descending argon is converted into heat content, for max flow 15m3/h this correspond to power: 15 x 1380 x 9.81 x 900=182 MJ/h or 51kW.

23. LIQUID ARGON FILLING LINE 23LAGUNA-LBNO LAr-Process Facilities Total power for maximum flow : 78kW Corresponding temperature increase : +11.4°C Liquid /vapor pressure supposing 5.6 barg at surface : 12 barg. Density of liquid : 1150kg/m3, with flow 15m3/h its 414tpd, so inner diameter of pipeline should be increased by 4%.

24. BOIL OFF RECONDENSATION UNIT 24LAGUNA-LBNO LAr-Process Facilities SIZING OF UNITS: Two sizing cases shall be considered :  During filling of LAr tank  During normal operation

25. BOIL OFF RECONDENSATION UNITS: Sizing for a 50 ktons LAr tank. 25LAGUNA-LBNO LAr-Process Facilities A - Heat to be removed during filling of tank: Source of HeatkW Heat coming into argon during transportation to site : 7 days mean 2 ways travel duration, 0.4% /day boil off for 18 m3 container, 500TPD : 7 x 0.004 x 500=14TPD 26 Heat in pumping at surface, assumed 30m LAr efficiency 60% : 500 000*9.81*30/(0.6*3 600 000*24) 2.8 Heat in vertical pipe 78 Re-condensation of volume of displaced gas by incoming liquid 4 Heat coming in the tank through insulation : 0.07% /day or 51ton/day 95 Heat with recirculation for purification : assumed 100m/h, 2 bar, efficiency 50% (including heat from motor) 11 Heat coming in the piping and equipment for on surface piping and equipment, argon condensation, argon recirculation, nitrogen piping 20 Total 1 to 7 heat during filling of tank 236

26. 26LAGUNA-LBNO LAr-Process Facilities B - Heat to be removed in normal operation : BOIL OFF RECONDENSATION UNITS: Sizing for a 50 ktons LAr tank. Source of HeatkW Heat coming in the tank through insulation : 0.07% /day or 51ton/day 95 Heat from scientific instrument in the tank ~0 Heat due to high voltage electric field: ~0 Heat with recirculation for purification : assumed 300m/h, 2 bar, efficiency 80%, 21 Heat coming in the piping and equipment for argon condensation, argon recirculation, nitrogen piping: 15 Total 1 to 5 heat during normal operation of tank 131

27. 27LAGUNA-LBNO LAr-Process Facilities Heat during filling. 236kW Heat during normal operation 131kW So we propose to install two units each sized for 131 kW: i.=> one spare, one in operation during normal operation period, ii.=> Two units in operation in parallel during the filling operation period. BOIL OFF RECONDENSATION UNITS: Sizing for a 50 ktons LAr tank. == ~ 2 Each unit is based on a nitrogen refrigeration loop (compression – expansion). The two units share the Ar / Nitrogen heat exchanger. Performance of each unit is 880kW mechanical power (with 36°C heat source, 75% efficiency of compressors, 88% efficiency of expander, minimum delta T in exchangers 3°C. We need 6.7kW mechanical for each kW (heat) extracted. Carnot maximum efficiency with cold produced at -184.5°C and heat rejected at +36°C is: T/Hc= (273+36)/(273-184.5)- 1=2.49kW/kW Minimum Carnot power would be 326kW. So efficiency versus max thermodynamic efficiency is rather poor: 37%. Nitrogen refrigeration loop

28. BOIL OFF RECONDENSATION UNITS: PERFORMANCE OF HEAT EXTRACTION UNIT(for 50kton tank ) 28 LAGUNA-LBNO LAr-Process Facilities Except rotating machine, there is a large loss with irreversibility in the LP N2/HP N2 exchanger. Large delta t at low temperature, 24°C at cold part Addition of 117kW Carnot power (+35%) is done by this exchanger only! This could be avoided using helium (right curve)or neon, which would have parallel heat flow curves in the LP/HP heat exchanger, but there would be only gas, instead of gas + liquid with N2, in the expander, so cold would be produced at a unnecessary low temperature ( minimum -228°C with the same pressures)

29. BOIL OFF RECONDENSATION UNITS: Brazed Aluminum Plate Fin Heat Exchanger 29 LAGUNA-LBNO LAr-Process Facilities

30. 30LAGUNA-LBNO LAr-Process Facilities Tank nominal size Heat during filling Heat during operationRatio units running for filling units running for operation power of unit (kW) kW kW on shafts 20 kton211722,9321485 50 kton2371311,8121880 100 kton3242491,3032840 BOIL OFF RECONDENSATION UNITS: Sizing summary for 20 / 50 & 100 ktons LAr tank.

31. LIQUID ARGON CIRCULATION & FILTRATION 31LAGUNA-LBNO LAr-Process Facilities When an event happens in the tank,a neutrino colliding with a argon atom, UV light is emitted and electrons are snatched from the argon atoms by charged particles issued from collision. Both light and electron circulate almost freely in liquid argon but a very low content of impurity especially electronegative impurities such as O2 molecules, absorb the light and capture electrons.

32. LIQUID ARGON CIRCULATION & FILTRATION 32LAGUNA-LBNO LAr-Process Facilities Curve from ICARUS 600tons argon detector in Grand Sasso ITALY  For 1.5km/s speed and 22 m: duration of travel of electron is 15ms.  Very low impurities content required, 0.05ppb O2 equivalent or less.  In case of recirculation stop, for instance between day 210 and day 220, oxygen content go from 0.05ppb to 0.12ppb.  This corresponds for half the capacity  (there is 2 cryostats) to 0.018g  oxygen coming in argon in 10 days.  Assuming that O2 is coming from surfaces in contact with argon, the 73000/325 volume ratio LAGUNA 50kT /ICARUS, gives a surface ratio of 37 thus 0.66g O2 in 10 day or 0.0011 ppb/day. So hopefully 50 days stop or recirculation should be no problem.

33. LIQUID ARGON CIRCULATION & FILTRATION 33LAGUNA-LBNO LAr-Process Facilities Impurities in commercial argon or coming from matter in contact with argon ( steel envelope, aluminum on roof, steel roof reinforcement, instrument cables, connectors in the roof, detectors of light and electrons, electric field generator, pumps ) are mainly : Water, Oxygen, Hydrocarbons. Filtration is done on liquid argon at -185°C, no filters is able to stop the 3 impurities, so 3 specific filters in series (or mixed common ones) are used: Molecular sieves for water, Active carbon for hydrocarbons, Copper powder for oxygen. Depending on the flow of argon to be treated, impurities content at inlet and outlet and optimized pressure drop, filtration unit should content one or several in parallel identical lines with the 3 types of filters.

34. LIQUID ARGON CIRCULATION & FILTRATION 34LAGUNA-LBNO LAr-Process Facilities Four filtration functions are foreseen for the LAr, the flows and impurity content at inlet varies and the impurity content at outlet is maybe to be optimized knowing the filters characteristics and cost. 1 - Filtration of commercial argon coming from surface. Flow= 15m3/h 4ppmv oxygen 1ppmv water Outlet : 10ppb? Flow O2 to be extracted = 67g/h, H2O = 9.4g/h Total to be extracted: O2=233kg H20=33kg.

35. LIQUID ARGON CIRCULATION & FILTRATION 35LAGUNA-LBNO LAr-Process Facilities 2 - Filtration with recirculation during filling period Flow = 60m3 /h? Starting O2 content = 10ppb? Content outlet = 1ppb? Flow O2 to be extracted =1g/h Total to be extracted: O2=530g 3 - Filtration on condensed boil of in normal operation Flow = 1.77m3 / h Starting O2 content = 10ppb? Content outlet = 0.05ppb Flow O2 to be extracted = 0.019g/h Duration of purification =? Or all life of detector

36. LIQUID ARGON CIRCULATION & FILTRATION 36LAGUNA-LBNO LAr-Process Facilities 4 - Filtration with recirculation of liquid argon Rate is 1 recirculation of volume /week (assuming that it remains at the O2 0.1ppb ) Flow = 400m3/h Starting O2 content = 0.1ppb Content outlet = 0.05ppb Flow O2 to be extracted = 0.021g/h Duration of purification =? Or all life of detector

37. LIQUID ARGON CIRCULATION & FILTRATION: Pumps for Filtration 37LAGUNA-LBNO LAr-Process Facilities Commercial argon arrives warm from surface at around -175°C and around 10 bar at LAr tank level, so no pump is required for the flow through purification unit then tank. In case of cold argon: 1 horizontal pump Flow: 15m3/h, Head around 20m Recirculation during filling requires a vertical in-tank pump going to bottom of tank, 1 vertical pump Flow 60m3/h Head around 50m.

38. 38LAGUNA-LBNO LAr-Process Facilities Condensed boil off is available at outlet of LN2 heat exchanger on roof of tank, 2 x 100% horizontal pumps Flow: 1.77m3/h Head: 20m Circulation of liquid argon during operation Pumps can be a horizontal pump in lateral cavern 1 m under level of liquid but large lateral outlet in tank is not recommended for safety reason, it’s even forbidden for LNG tanks. So pumps will be in-tank pumps going down some 1 m below liquid level. 2 x 100% in tank vertical pumps Flow: 400m3/h Head: 25m LIQUID ARGON CIRCULATION & FILTRATION: Pumps for Filtration

39. 39LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON CIRCULATION & FILTRATION: In-tank pumps Ebara pumps

40. 40LAGUNA-LBNO LAr-Process Facilities LIQUID ARGON CIRCULATION & FILTRATION: Filtration

41. LIQUID ARGON CIRCULATION & FILTRATION 41LAGUNA-LBNO LAr-Process Facilities Assuming for each filtration function for each component is done by one filter with area S and length along the flow L Assuming that volume of filter S x L is proportional to the impurity flow eliminated by filters, Qo 2 that would mean that filters for each filtration function are changed or regenerated at constant time interval,. Assuming that pressure drop is constant for each filtration function, using Darcy law, (Qar/S)*L = 1 We get: L= (Qo 2 /Qar) 1/2 and S= (Qo 2 *Qar) 1/2

42. LIQUID ARGON CIRCULATION & FILTRATION 42LAGUNA-LBNO LAr-Process Facilities This simple approach show that filters for commercial argon is by far the largest and probably can be used for the other functions, with adapted periods between regeneration and pressure drops. Flow (m3/h) Flow of impurity (g/h)LengthArea Filtration of commercial argon15672,1131,70 Recirculation during filling10010,110 Condensed boil off filtration1,770,0190,1030,18 Recirculation during operation4000,0170,0072,26

43. 43LAGUNA-LBNO LAr-Process Facilities N2 to & from cooling loops To & from filtration units To relief & vacuum valves To filtration unit In-tank pump for filling period In-tank pumps for normal operation TANK PROCESS EQUIPMENT & NOZZLES c

44. 44 LAGUNA-LBNO LAr-Process Facilities TANK PROCESS EQUIPMENT & NOZZLES Nitrogen refrigeration loop Filtration unit A Filtration unit B Relief & vaccum valves Filling line

45. 45 LAGUNA-LBNO LAr-Process Facilities TANK PROCESS EQUIPMENT: Process & electrical excavated room 64 m 25 / 30 m 12 /15 m 7 m Process area Electrical area Shaft for filling line Ventilation Shaft Lar Tank

46. AIR PURGE AND COOLING DOWN 46LAGUNA-LBNO LAr-Process Facilities If liquid argon is introduced in the tank, with the effect of heat brought by envelope the reduction of the volume of air with the temperature reduction is less than volume taken by vaporized argon so air goes out the tank. For each ton of liquid argon temperature would decrease by 1°C When dew point of water will be reached, rain or snow will fall in the tank, quantity with saturation at 20°C will be 900kg water. That not finished, at -90°C a snow of CO 2 will fall from remaining air. Initial quantity of CO2 in air in tank is 38kg. In order to avoid that all air will be removed with gaseous argon. AIR PURGING

47. AIR PURGE AND COOLING DOWN 47LAGUNA-LBNO LAr-Process Facilities Argon should be introduced at the bottom of tank with descending pipe, and air extracted on top, as argon is 38% heavier than air there will be a good piston effect. For smaller tanks after 2 time the volume of tank, most of air is removed, with argon introduced at 10°C Density 112000Pa x 0.040kg/(8.32 x283°K)=1.9kg/m3 Quantity of argon is 2 x 61700m3x 1.9=234tons. AIR PURGING

48. AIR PURGE AND COOLING DOWN 48LAGUNA-LBNO LAr-Process Facilities Commercial used argon will come from the 300m3 buffer tank at surface and will be vaporized at bottom with mobile air vaporizer. Heat required is 16 000kWh, with 2 days duration vaporizer is 333kW. Air then argon is vented on top flow of argon is 4.87tons/hour, or 0.7m3/s, with ventilation rate of 30m3/s, argon content in air is 3.2%. AIR PURGE

49. AIR PURGE AND COOLING DOWN 49LAGUNA-LBNO LAr-Process Facilities Cooling down is done by introducing liquid argon at bottom and extracting some exceeding argon gas on top. With following hypothesis: Tank full of gaseous argon at 10°C and around 1.12bara after air purge 800 tons steel equivalent heat capacity of tank including instruments and half insulation heat capacity. No use of argon re-condensation during cooling down cool COOLING DOWN OF TANK

50. AIR PURGE AND COOLING DOWN 50LAGUNA-LBNO LAr-Process Facilities cool COOLING DOWN OF TANK Cooling down requires around 400tons LAr. With temperature variation of 5°C /hour: Duration is 80 hours with flow 5t/h. Max % flow to be vented versus inlet flow is 72% at beginning, 3.5 tons /hour less than flow for air purging.

51. AIR PURGE AND COOLING DOWN 51LAGUNA-LBNO LAr-Process Facilities cool COOLING DOWN OF TANK During most of cooling down argon has to be vented as reduction of volume with temperature reduction is less than volume of vaporized liquid. After 370 tons corresponding to -160°C, it’s the reverse, there is volume reduction so without caution air will enter!

52. AIR PURGE AND COOLING DOWN 52LAGUNA-LBNO LAr-Process Facilities cool COOLING DOWN OF TANK Around 150 tons are vented (90k€) It’s possible to reduce that using simultaneously introduction of LAr and use of gas condensation units. With 2 units running and 262kWh removed and LAr mass 1.36ton Temperature decrease is 3.3°C /hour and vented argon 0. To reach -3.3°C without condensation units requires 5 tons, so for 262kWh or 13€, 3.64 tons LAr worth 2200€ is saved. Using condensation units can reduce to 0 vented argon during cooling down but be cautious to avoid air inlet. At the end of cooling-down, below -160°C heat as to be added or liquid flow reduced in order to avoid air inlet!

53. CAVERN AMBIENT AIR TEMPERATURE CONTROL 53LAGUNA-LBNO LAr-Process Facilities cool c I.Heat from coolers of condensation unit : 1,030kW II.Heat from losses motor of compressor of condensation unit: 50kW III.Heat removed from cavern by tank and piping: -110kW Net heat 970kW With 2 units running during filling period With lighting, HVAC, instrumentation, control, electricity, motors of pumps loss ( water, argon ) : Around 2,200kW

54. CAVERN COOLING 54LAGUNA-LBNO LAr-Process Facilities cool c 2200kW removal with air ventilation and 10°C requires 170m3/s air, 30m3/s available from mine system. With water and 10°C flow 189m3/h 2 vertical pipes 6 inches. Pressure drop 4.5%, loss 80m for 2*900m. Pumps on surface, 189m3/h 90m 66kW. Water/water from lake or air cooler on surface.

55. POSSIBLE PROBLEMS WITH LEAKS 55LAGUNA-LBNO LAr-Process Facilities cool c 3 CATEGORIES OF LEAKS Small leaks which can be repaired: With access outside the wall and removal of some insulation, maybe leak can be repaired with a patch weld over the leak on -185°C steel (with good argon shield) ?, on injection of resin under pressure?? Small leak that cannot be repaired, say leak which can be diluted with 30m3/s ventilation, less than 6m3/s argon,42ton /h, removing 2000kW heat, water system is used the reverse way to remove that cold. Empty the tank to surface using : a.In tank low flow circulation pump boosting a 130bar pump, then vertical pipe to surface. b.Flow around 10m/h, depending ot the leak flow and height in the tank,10 months max to empty the tank.

56. POSSIBLE PROBLEMS WITH LEAKS 56LAGUNA-LBNO LAr-Process Facilities c Large leak: Large leak cannot be repaired, no oxygen close to the leak and -185°C. Forget the neutrinos for a while everybody has to leave. Liquid argon go to bottom of cavern and boils, heat coming from rock can limit gaseous argon flow to less than liquid leak flow. Gaseous Ar find his way to the surface through the gallery or the borehole over the LAr tank. With the flow of Gaseous Ar and pressure drop with this flow, pressure in the caverns increases.

57. POSSIBLE PROBLEMS WITH LEAKS 57LAGUNA-LBNO LAr-Process Facilities cool c The problem is that the pressure inside is connected to temperature of liquid argon and doesn’t change. So there is risk of implosion of the roof and upper part of wall, so gaseous argon boiling from the leak outside in the cavern must go into the tank. Butterfly valves on boil off pipe are done for that, but system must operate at low temperature. After some time depending of the leak and the heat flow from rock there is no argon left, but rock is a little cold. With ventilation rock is heated

58. POSSIBLE PROBLEMS WITH LEAKS 58LAGUNA-LBNO LAr-Process Facilities cool c If roof of cavern has not fallen on the tank with low temperature and corresponding traction stress in the rock, When temperature go to around -30°C leak is repaired from outside and inside the tank. And we can go back to purge of air and cooling down, then neutrino detection. And we are lucky, cooling down last less time as initial temperature is lower.

59. 59LAGUNA-LBNO LAr-Process Facilities cool c All electric power at bottom is converted into heat and there is no other heat source, so power is idem heat to be removed : 2,200kW. In 6,000V 230A so 3 x 120mm2 copper cable is OK, 0.18 Ohm/km, voltage drop 40V. 2 x Cables 100% either hanged in borehole from surface,underground mining cables with free hanging length 1200m. Or if 2 cables 6,000V are available in the mine from 0 to -900m, addition of cables in the gallery from mine to LAr tank. Equipment on surface : connection of cables on mine 6,000V switchboard, use of existing 110kV line, circuit breaker, 110kV/6,000V transformers, 6,000V switchboard. ELECTRIC POWER

60. 60LAGUNA-LBNO LAr-Process Facilities cool c Electrical equipment at bottom:  6,000V switchboard with:  2 arrivals  2 departures to 6,000 V motors of compressor in boil off condensation unit  2 departures 100% to small 6,000V/400V transformers  2 x 6,000V/400V transformers  1 x 400V switchboard with departures for small motors, lighting panel, HVAC, control, instrumentation, electric field generator etc… ELECTRIC POWER

61. THANK YOU FOR YOUR ATTENTION 61LAGUNA-LBNO LAr-Process Facilities