Formation and Characterization of Aerobic Granules in a Sequencing Batch Reactor Treating Soybean-Processing Wastewater
- 23 February 2005
- journal article
- research article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 39 (8), 2818-2827
- https://doi.org/10.1021/es048950y
Abstract
Aerobic granules were cultivated in a sequencing batch reactor (SBR) fed with soybean-processing wastewater at 25 ± 1 °C and pH 7.0 ± 0.1. The granulation process was described via measuring the increase of sludge size. The formation of granules was found to be a four-phase process, that is, acclimating, shaping, developing, and maturated. A modified Logistic model could well fit with the granule growth by diameter and could be employed to estimate the maximum diameter, lag time, and specific diameter growth rate effectively. Both normal and log-normal distributions proved to be applicable to model the diameter distribution of the granules. The granule-containing liquor was shear thinning, and their rheological characteristics could be described by using the Herschel−Buckley equation. The suspended solids concentration, pH, temperature, diameter, settling velocity, specific gravity, and sludge volume index all had an effect on the apparent viscosity of the mixed liquor of granules. The matured granules had fractal nature with a fractal dimension of 1.87 ± 0.34. Moreover, 83% of matured granules were permeable with fluid collection efficiencies over 0.034. As compared to activated sludge flocs, the aerobic granules grown on the soybean-processing wastewater had better settling ability, mass transfer efficiency, and bioactivity.Keywords
This publication has 15 references indexed in Scilit:
- Anaerobic sludge granulationWater Research, 2004
- Characterization and evaluation of aerobic granules in sequencing batch reactorJournal of Biotechnology, 2003
- State-of-the-art: rheological characterisation of wastewater treatment sludgeBiochemical Engineering Journal, 2003
- The rheological and physico-chemical characteristics of sewage sludgesEnzyme and Microbial Technology, 2002
- Comparison of simple neural networks and nonlinear regression models for descriptive modeling of Lactobacillus helveticus growth in pH-controlled batch culturesEnzyme and Microbial Technology, 2000
- The effect of dissolved oxygen concentration on the structure, size and size distribution of activated sludge flocsWater Research, 1999
- Aerobic granular sludge in a sequencing batch reactorWater Research, 1997
- Gas/liquid mass transfer in stirred vesselsChemical Engineering Science, 1992
- Oxygen transfer in slurry bioreactorsBiotechnology & Bioengineering, 1991
- Polychlorinated dibenzo-p-dioxins and dibenzofurans in the ambient atmosphere of Bloomington, IndianaEnvironmental Science & Technology, 1989