 |
Introduction
Our photoacoustic systems are continuously compared with other reference methods such as:
1. wet chemical methods (e.g. for ammonia measurements)
2. titration (e.g. for hydrogen-sulfide measurements)
3. a home-made frost-point humidity generator. which was approved as a secondary standard by the Hungarian National Office of Measures (for water vapor measurements)
One of our goals is to increase the reliability of our reference methods and correspondingly our photoacoustic systems. Therefore in 2005 we have started
the procedure of accreditation of a calibration laboratory by the Hungarian National Accreditation Body for instruments measuring hydrogen sulfide and water vapor concentration in natural gas. This accreditation is financed by a Economic Competitiveness Operational Programme (GVOP-3.2.1.-2004-04-0246/3.0 „Accreditation of water vapor and hydrogene-sulphide measurements ” 2005-2006.)
Frost-point humidity generator
The principle of the frost point humidity generator in the calibrating system was that developed by Morris in 1997. Our frost-point humidity generator is a home made self developed system, which produce a stream of gas with a known condensation point. Briefly, humidified nitrogen passed through a saturator cooled by liquid nitrogen. The temperature of the cooling bath was measured by a
PT100 temperature sensor. Knowing the pressure in the gas stream one can calculate the water content of the stream.
|
|
 |
Our multi-wavelength photo- acoustic aerosol system was successfully tested in a measurement campaign at the Research Center Karlsruhe (18-28 April 2006).
|
|
|
