We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Effect of Bubble-Induced Surface Turbulence on Gas-Liquid Mass Transfer in Diffused Aeration Systems.
- Authors
Monteith, H. D.; Bell, J. P.; Parker, W. J; Melcer, H.; Harvey, R. T.
- Abstract
Models that predict volatilization of organic compounds from wastewater treatment basins may underestimate emission rates if the surfaces are considered as quiescent. In reality, the water surface may be agitated by subsurface aeration, increasing mass transfer across the tank surface air-water interface. This study investigated the effect of turbulence, induced by diffused bubble aeration, on mass transfer at the water surface of a pilot aeration basin. The mass transfer of ammonia from an enclosed headspace over the basin to acidified water was measured when different diffuser types and airflow rates were applied. Oxygen-transfer tests were conducted immediately following each ammonia-transfer test. Increasing airflow rates through fine- and coarse-bubble diffusers had a significant effect on the ammonia mass-transfer rate. Experimental mass-transfer parameters (KLa's) for surface volatilization derived with aeration present were up to 48% higher than the KLa values for quiescent conditions over the range of conditions tested. No effect of diffuser type on ammonia transfer could be determined. The study results infer an effect on oxygen transfer into the water at the surface and potential transfer of volatile organic compounds, if present, from the water. The results of the ammonia mass-transfer experiments suggest that adjustments to the existing mass transfer correlations for surface volatilization from aeration basins may be in order. Such adjustments will have the greatest effect on predictions for the less volatile compounds, under conditions of low airflow rates. Water Environ. Res., 77, 128 (2005).
- Subjects
SEWAGE aeration; WASTEWATER treatment; ORGANIC compounds; INDUSTRIAL wastes; TURBULENCE; AMMONIA; VAPORIZATION in water purification
- Publication
Water Environment Research (10614303), 2005, Vol 77, Issue 2, p128
- ISSN
1061-4303
- Publication type
Article
- DOI
10.2175/106143005X41690