search
for
 About Bioline  All Journals  Testimonials  Membership  News  Donations


International Journal of Environment Science and Technology
Center for Environment and Energy Research and Studies (CEERS)
ISSN: 1735-1472
EISSN: 1735-2630
Vol. 3, No. 4, 2006, pp. 425-433
Bioline Code: st06052
Full paper language: English
Document type: Research Article
Document available free of charge

International Journal of Environment Science and Technology, Vol. 3, No. 4, 2006, pp. 425-433

 en Rectangular tank surface aerators: scale up criteria and energy conservation
A. R. Rao and B. Kumar

Abstract

Surface aeration experiments were conducted in two types of rectangular tanks of aspect ratios i.e., length to width ratio (L/W) of 1.5 and 2 and developed simulation equations to correlate the oxygen transfer coefficient, k and power number, P0 with a parameter governing theoretical power per unit volume X. The parameter X is defined as equal to F4/3R1/3, where F and R are impellers' Froude and Reynolds numbers respectively). Results have shown that the P0 can not be simulated singularly with either Reynolds number, R or Froude number, F, which results in scaleeffects; there appears to be a need to incorporate the effects of both F and R. It was found that P0 is uniquely related to X for rectangular aeration tanks of both aspect ratios, however, such relationships are different depending upon the aspect ratios. It has been demonstrated that energy can be saved substantially if the aeration tanks are run at relatively higher input powers. It is also demonstrated that smaller sized tanks are more energy conservative and economical when compared to big sized tanks, while aerating the same volume of water, and at the same time by maintaining a constant input power in all the tanks irrespective of their size.

Keywords
Froude number, oxygen transfer coefficient, power number, power per unit volume, Reynolds number, surface aerators, water and wastewater treatment

 
© Copyright 2006 Center for Environment and Energy Research and Studies (CEERS)
Alternative site location: http://www.ijest.org

Home Faq Resources Email Bioline
© Bioline International, 1989 - 2017, Site last up-dated on 05-Dec-2017.
Site created and maintained by the Reference Center on Environmental Information, CRIA, Brazil
System hosted by the Internet Data Center of Rede Nacional de Ensino e Pesquisa, RNP, Brazil