www.atmos-meas-tech-discuss.net/2/1143/2009/ doi:10.5194/amtd-2-1143-2009 © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Design and performance of an automatic regenerating adsorption aerosol dryer for continuous operation at monitoring sites Leibniz Institute for Tropospheric Research, Leipzig, Germany Abstract. Sizes of aerosol particles depend on the relative humidity of their carrier gas. Most monitoring networks require therefore that the aerosol is dried to a relative humidity below 50% RH to ensure comparability of measurements at different sites. Commercially available aerosol dryers are often not suitable for this purpose at remote monitoring sites. Adsorption dryers need to be regenerated frequently and maintenance-free single column Nafion dryers are not designed for high aerosol flow rates. We therefore developed an automatic regenerating adsorption aerosol dryer with a design flow rate of 1 m3/h. Particle transmission efficiency of this dryer has been determined during a 3 weeks experiment. The lower 50% cut-off was found to be below 3 nm at the design flow rate of the instrument. Measured transmission efficiencies are in good agreement with theoretical calculations. One drier has been successfully deployed in the Amazonas river basin. From this monitoring site, we present data from the first 6 months of measurements (February 2008–August 2008). Apart from one unscheduled service, this dryer did not require any maintenance during this time period. The average relative humidity of the dried aerosol was 27.1+/−7.5% RH compared to an average ambient relative humidity of nearly 80% and temperatures around 30°C. This initial deployment demonstrated that these dryers are well suitable for continuous operation at remote monitoring sites under adverse ambient conditions. Discussion Paper (PDF, 1376 KB) Interactive Discussion (Closed, 4 Comments) Final Revised Paper (AMT) Citation: Tuch, T. M., Haudek, A., Müller, T., Nowak, A., Wex, H., and Wiedensohler, A.: Design and performance of an automatic regenerating adsorption aerosol dryer for continuous operation at monitoring sites, Atmos. Meas. Tech. Discuss., 2, 1143-1160, doi:10.5194/amtd-2-1143-2009, 2009. Bibtex EndNote Reference Manager XML |
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