Thermo Scientific Omni FTIR Multi Gas CEMS, Инструкция по эксплуатации

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Calibration
Calibration Gases
4-4 Omni FTIR Multi Gas CEMS Instruction Manual Thermo Fisher Scientific
To perform a daily calibration check, a sufficient calibration gas flow is
necessary. Relative to the sampling flow rate of 5 LPM, a 6 LPM cal gas
flow rate is recommended. If the cal gas line is directly connected to a gas
cylinder, an HCl concentration of 50 ppm is strongly recommended, in
terms of HCl long term stability. Such a gas cylinder can be purchased
from Air Liquide. For an A size cylinder with a pressure of 2300 psi, a
newly purchased gas cylinder is estimated to last for two months. If the cal
gas is diluted from a high concentration gas cylinder (for instance 1000
ppm), one gas cylinder would last much longer, and may be also beneficial
for HCl long term stability.
A similar requirement for the NH
3
cylinder gas is suggested. Relatively,
NH
3
has a faster response time than HCl, so a shorter duration for the
NH
3
daily calibration check can be chosen. In this case, the NH
3
gas
cylinder will last much longer than the HCl cylinder.
For other less reactive gases, a 6 minute duration for the daily calibration
check would be sufficient. A newly purchased A size gas cylinder may last
for 6 months.
The gas concentrations for daily calibration checks should correlate to the
typical emission level of the monitoring sources.
To generate HCl, HF, NH
3
and H
2
0 standards using HovaCAL
Calibration Gas Generator, IAS model HovaCAL digital 211 MF, the
following concentrations are recommended.
HCl 0.002 mol/l
HF 0.002 mol/l
NH3 0.005 mol/l
In addition to a HovaCAL, a high concentration gas cylinder for HCl
(~1000 ppm) is recommended. A gas calibrator such as Thermo Scientific
Model 146
i should be used to dilute HCl to the desired value for both span
check and spike check. To perform the spike check, the same HCl gas
cylinder mixed with 100 ppm SF6 is recommended.
Calibration
Gases