SAMPLE STREAM DRYER
SAMPLE STREAM DRYER
Drying the aerosol sample stream is highly recommended to provide accurate measurement data and to protect equipment from water condensation.
In hot, humid locations, the water vapor content of the ambient sample air may be very large. This can lead to inaccuracies in aerosol analysis such as the BC measurement – but, more seriously, there is the possibility of water condensation inside analytical instruments which can lead to permanent damage. This issue is solved by the use of our Sample Stream Dryer.
The interaction of water with aerosol species changes their physical properties. Consequently, the World Meteorological Organization has recommended that all aerosol measurements should be performed under conditions where the Relative Humidity is 40% or lower (WMO/GAW 2003; Wiedensohler, 2014).
Many stations in hot, humid locations have air-conditioned interiors. If the indoor air-conditioning temperature Ta is comparable to or lower than the dewpoint (condensation temperature) Td of the outside ambient air, water will condense in the tubing and inside the instrument. This will not only completely in-validate the data, but it can also cause permanent damage to the instrument.
The Magee Scientific Sample Stream Dryer removes water vapor from the inlet flow by means of a semi-permeable Nafion membrane. This membrane selectively absorbs molecules of water vapor from the air-stream and passes them to a space on the other side of the membrane, maintained at a low absolute pressure by means of a vacuum pump.
The Magee Scientific Sample Stream Dryer can reduce the dew point temperature by up to 14 degrees Celsius at a flow rate of 5 LPM. The equipment is self-contained, automatic, and includes a display screen which shows the input and output hygrometric properties. A data cable can connect to the Model AE33 Aethalometer so that the temperature and humidity data are incorporated into the Aethalometer’s data files.
The Magee Scientific Sample Stream Dryer can be used to remove water vapor from the inlet stream to any aerosol instrument, not just an Aethalometer.
- Nafion® membrane technology
- Sample flow rate to 5 LPM
- Excellent drying efficiency – up to 14°C decrease of dew point
- Extremely low particle loss – < 4 %
- 100% compatible with AE33 Aethalometer®
- Fully functional as stand-alone device
- Ambient Air Quality monitoring in humid locations
- Laboratory aerosol studies
- Direct combustion emissions measurement
- Low temperature sampling (drying does not affect volatiles)