T201 Ammonia Analyzer | Teledyne API Model T201 NH3 Analyzer Operator Manual |
As can be seen from the above reactions, the calculation of the ammonia concentration and overall calibration of the instrument must be done carefully, if accurate ammonia concentrations are to be measured.
1.2SPECIAL CONSIDERATIONS FOR AMMONIA MEASUREMENT
Ammonia is a difficult gas to measure due to its chemical characteristics. The gas tends to adsorb onto surfaces and diffuse into many materials. The following precautions should be observed when designing ammonia sampling systems and connecting them to the T201 analyzer:
Do NOT use copper tubing or fittings designed for household plumbing.
Use ONLY Chromatography grade (cleaned, passivated) stainless steel tubing.
Use ONLY glass for sample inlet manifold.
ALWAYS keep the tubing from the M702SS calibrator to the analyzer as short as possible. USE stainless steel tubing throughout, especially from the ammonia calibration bottle to the calibrator.
If possible HEAT the sample line and DRY the sample gas.
Sample filters will cause response delays on both the rise and fall of the sample signal.
These rules apply also to your calibrator’s internal plumbing. It is highly recommended that you use a M702SS calibrator in conjunction with the T201. The calibrator has stainless steel plumbing throughout. The T700 calibrator contains Teflon tubing and internal MFC’s that can be affected by the ammonia gas, therefore, the T700 calibrator is not recommend for use with the T201 analyzer. It is important to keep the sampling system well maintained.
1.3SAMPLE FILTRATION
| The instrument can be provided with an optional stainless steel sample |
| filter P/N 05571. For minimum response time operation, the instrument |
| should be supplied with clean sample gas at ambient pressure. |
| An additional filter resides in the T201 pneumatic pathway. The filter is a |
| ¼” diameter stainless steel sintered filter used to protect the reaction cell |
| flow control orifice from plugging. This filter will plug rapidly if |
| contaminated sample gas is not filtered before entering the analyzer. |
Note | In situations where the sample gas is known to be contaminated with |
| particulate material, it is advisably to add extra filtration. However, it must be |
| noted that the response time is directly extended through filter additions. |
12 | 07271B DCN6646 |
