Ozone's effects on power-law particle size distribution in recirculating aquaculture systems
V.
Krumins, J.M. Ebeling, F. Wheaton-2001
Aquacultural Engineering,
25 (1): 13 - 24
Abstract:
A
power law model for particle size distributions has been applied by several
researchers to aquacultural and aquatic systems Rueter and Johnson [Aquacult.
Eng. 14 (1995) 123] demonstrated that ozonation of trout hatchery water
increased the proportion of large particles in the water. Summerfelt
et al. [Aquaculture 158 (1997) 57]
speculated that this increase in particle size led to their observed
improvement in screen filter performance in a recirculating aquaculture
system. While ozonation increases the relative abundance of larger
particles, these particles are continuously removed by clarifiers in
recirculating systems. This project examines the effect of ozonation on the
particle size distribution remaining in the system at steady state
conditions. In these experiments, the power law modeled the particle size
distribution data very well for the majority of trials. Surprisingly,
regardless of ozone dose, there was no significant difference in the slope
of the power law fit for the particle size distribution. In over one-half of
the experimental trials when no ozone was added, the particle size
distributions were distinctly bimodal. The power law model for particle size
distribution did not fit these data very well. When the power law did not
fit the data, 50% of particles were smaller than 14 µm, and the turbidities
measured in the production tank were significantly higher than when the
particle distribution obeyed the power law.
(Biological
Resources Engineering Department, University of Maryland, College Park, MD
20742, USA, Tel.: +1-301-4052223; fax: +1-301-3149023, e-mail: fw4@umail.umd.edu)