Bacterial (Total Coliform) Die-Off in Maturation Ponds

Abstract

A mathematical model of bacterial (total coliform) die-off in maturation ponds was developed based on first order kinetics. Laboratory single factor and dynamic model pond tests were carried out, using effluent from a municipal trickling filter wastewater treatment plant. Correlations were found between two groups of factors which were found to have a significant effect on the first order rate coefficient: the environmental factors, temperature, pH and organic loading; and the illumination-related factors, sunlight intensity, depth, algal concentration and turbidity. These correlations were used in the model along with the physical configuration factors, dimensions (depth, width and length), detention time and dispersion number and a calibrated dispersion model. Predictions of the bacterial die-off using the model agreed well with experimental results obtained from the dynamic model pond tests.