Argon

1
Argon

• Refrigeration
• Supply
• Purity

2
Argon Refrigeration

• Heat load summary
• LN circulation
• LN supply

3
Heat Load Summary

• Tank heat load 0.05/day 47kW
• Flash during filling, assuming
• 5 psig supply 6kW
• Vapor displaced during filling 1.5 kW
• Total with 1.25 factor 68 kW

4
LN Supply Perspective

• Flare Usage 34 tons/day
• Fermilab usage 45 to 78 tons/day
• CHL liquefier 100 ton/day
• 12 trucks or 5 railcars per week
• LN cost at Fermilab 62/ton
• 2002 budget price for 100 ton/day liquefier 2.9
  million

5
Nitrogen Circulation

• Condensers inside tank to minimize argon handling
• Redundant pumps, heat exchangers, etc.
• Nothing extraordinary
• Needs further development to improve cost
  estimate
• Present estimate 460k

6
LN Supply Tasks

• Five liquefier vendors contacted recently
• Failures
• Power failures
• Mechanical breakdowns
• LN leak inside detector tank
• Supply interruptions
• Detector Tank loses 25 tons argon/day without
  cooling
• Zero backflow vent system needed

7
Argon Supply

• Praxiar quotation in January 2004
• 37 million, truck delivery, 1ppm
• RR cars would be less expensive
• Oxygen concentration is negotiable, 1ppm is
  proven without extraordinary effort
• Could use multiple suppliers

8
Argon Receiving

• Procedure proven at Dzero, NWA and E706
• Connect to truck
• Test carefully, accept or reject
• Testing includes oxygen concentration, electron
  lifetime, possibly other tests
• Pump through purifier into intermediate tank
• Test and pump into detector tank

9
Receiving Further Development

• Failure scenarios
• Adding contaminated delivery to main tank
• Spill during connection
• Further development
• Piping Schematic
• Instrumentation requirements
• Estimated time to connect and test

10
Sources of impurity

• Argon Supply
• Surfaces
• Tank shell
• Cable insulation
• Other material
• Leaks and permeation
• Mechanical seals
• Dead volumes

11
Argon Purifiers

• Purifying equipment would probably run for the
  life of the project as well as during filling
• ICARUS used Messer Oxisorb, proprietary
  regeneration
• Air Liquide offers a packaged liquid purifier,
  400k. Regeneration would consume 800k of argon
  during filling. Possibly can recover most of it.
• Praxair offers gas purifier for 600k
• Earnhart(Trigon) offers regenerable adsorbent
• All of these should be evaluated further

12
High Purity Specifications

• Rough tank purging
• High capacity intermediate system?
• Further purging?
• High purity system with high regeneration?
• Specification for leak testing
• Specification for tank surfaces, tank cleaning,
  procedures during detector construction, cable
  insulation
• Specification for all argon handling equipment
  and piping
• Further development needed

13
Purification Testing

• Testing is needed to prove high purity can be
  achieved without evacuation and with reasonable
  fabrication requirements
• Outgassing in vacuum has been studied, but how is
  the rate affected by an Argon atmosphere or
  temperature?
• Testing can be done on a reasonable scale

14
Effort estimates

• Purity issues, a man-year of process engineering,
  plus technician and drafting support
• MS budget to avoid re-inventing parts that are
  commercially available, 100k
• Refrigeration and Supply, two man-months of
  engineering to improve cost estimate