Abstract
In this report we describe the results of a study conducted to determine the rates of bacterial aerosol emission from the surfaces of the aeration tanks of the Metropolitan Water Reclamation District of Greater Chicago John E. Egan Water Reclamation Plant. This study was accomplished by conducting test runs in which Andersen six-stage viable samplers were used to collect bacterial aerosol samples inside a walled tower positioned above an aeration tank liquid surface at the John E. Egan Water Reclamation Plant. The samples were analyzed for standard plate counts (SPC), total coliforms (TC), fecal coliforms, and fecal streptococci. Two methods of calculation were used to estimate the bacterial emission rate. The first method was a conventional stack emission rate calculation method in which the measured air concentration of bacteria was multiplied by the air flow rate emanating from the aeration tanks. The second method was a more empirical method in which an attempt was made to measure all of the bacteria emanating from an isolated area (0.37 m2) of the aeration tank surface over time. The data from six test runs were used to determine bacterial emission rates by both calculation methods. As determined by the conventional calculation method, the average SPC emission rate was 1.61 SPC/m2/s (range, 0.66 to 2.65 SPC/m2/s). As determined by the empirical calculation method, the average SPC emission rate was 2.18 SPC/m2/s (range, 1.25 to 2.66 SPC/m2/s). For TC, the average emission rate was 0.20 TC/m2/s (range, 0.02 to 0.40 TC/m2/s) when the conventional calculation method was used and 0.27 TC/m2/s (range, 0.04 to 0.53 TC/m2/s) when the empirical calculation method was used.(ABSTRACT TRUNCATED AT 250 WORDS)
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- ANDERSEN A. A. New sampler for the collection, sizing, and enumeration of viable airborne particles. J Bacteriol. 1958 Nov;76(5):471–484. doi: 10.1128/jb.76.5.471-484.1958. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kenline P. A., Scarpino P. V. Bacterial air pollution from sewage treatment plants. Am Ind Hyg Assoc J. 1972 May;33(5):346–352. doi: 10.1080/0002889728506659. [DOI] [PubMed] [Google Scholar]
- LEDERBERG J., LEDERBERG E. M. Replica plating and indirect selection of bacterial mutants. J Bacteriol. 1952 Mar;63(3):399–406. doi: 10.1128/jb.63.3.399-406.1952. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Randall C. W., Ledbetter J. O. Bacterial air pollution from activated sludge units. Am Ind Hyg Assoc J. 1966 Nov-Dec;27(6):506–519. doi: 10.1080/00028896609342464. [DOI] [PubMed] [Google Scholar]