PerkinElmer AVIO 500, Руководство по оборудованию и обслуживанию для клиентов

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Preparing Your Laboratory
Either liquid or gaseous argon can be used with an ICP-OES system, although
liquid is recommended. The choice of liquid argon or gaseous argon tanks is
determined primarily by the availability of each and the usage rate. Liquid argon is
usually less expensive per unit volume to purchase, but cannot be stored for
extended periods. If liquid argon is used, the tank should be fitted with an over-
pressure regulator, which will vent the tank as necessary to prevent the tank from
becoming a safety hazard. Gas transfer lines from the argon tank should be
contaminant-free and not made of plastic.
It is highly recommended that the optical path be purged with either nitrogen or
argon. Nitrogen is the recommended purge gas due to its lower cost. Normal purge
gas usage is user-selectable at either 1.5 L/min (low purge) or 8 L/min (high purge)
for nitrogen (1.4 L/min or 7 L/min if argon is used) at 365 kPa (50 psig) pressure.
Gaseous argon tanks do not require venting and consequently can be stored for
extended periods without loss. The available argon pressure should be between 550
and 825 kPa (80-120 psig). Liquid argon and nitrogen may be purchased from your
gas supplier. The Avio 500spectrometer includes the hoses necessary for
connecting the argon and nitrogen to the instrument (0.25-inch Swagelok®
connection).
For the Avio 500, typical argon consumption would be 10 SLPM argon while the
plasma is running in a low-flow condition and 1 SLPM for detector purge at all
other times; for an instrument running 8 hours per day and 5 days per week at low
flow, this would result in a consumption rate of approximately 32,000 SL per week.
At that rate, a typical 160-liter liquid argon tank would last approximately 4 weeks,
depending on storage conditions; a typical 8000 liter compressed argon cylinder
would last approximately 1.8 days.
The argon gas regulator should provide a delivery pressure between 80 and 120 psi
(550 to 825 kPa). The nitrogen purge gas regulator should provide a delivery
pressure between 40 and 120 psig (275 to 825 kPa). A cylinder regulator that can
Nitrogen

20 ppm
Hydrogen

1 ppm
Hydrocarbons

1 ppm
Specification Argon Nitrogen