Modeling the Activated Sludge—Thickening Process in Secondary Settlers
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sampling
2.2. Sludge Thickening and Settling Tests
2.3. Model Development
2.3.1. Return Sludge Concentration Model
2.3.2. Sludge Compression Settling Model
2.4. Activated Sludge Fractal Dimensions
3. Results and Discussion
3.1. Model Calibration
WWTP | SVI (mL/g) | a | b | R2 | p |
---|---|---|---|---|---|
1 | 59.3 | 11.73 | 0.0496 | 0.88 | <0.001 |
2 | 59.6 | 11.54 | 0.0460 | 0.78 | <0.001 |
3 | 71.8 | 10.59 | 0.0500 | 0.86 | <0.001 |
4 | 201.8 | 6.74 | 0.0402 | 0.88 | <0.001 |
3.2. Model Validation
3.2.1. Return Activated Sludge Concentration Model Validation
3.2.2. New Sludge Compression Model Validation
3.3. Factors Affecting the Sludge Thickening
3.3.1. Sludge Height
3.3.2. Stirring Rates
3.4. Activated Sludge Fractal Dimension
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
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Zhang, Y.; Yin, X.; He, Z.; Zhang, X.; Wen, Y.; Wang, H. Modeling the Activated Sludge—Thickening Process in Secondary Settlers. Int. J. Environ. Res. Public Health 2015, 12, 15449-15458. https://doi.org/10.3390/ijerph121214996
Zhang Y, Yin X, He Z, Zhang X, Wen Y, Wang H. Modeling the Activated Sludge—Thickening Process in Secondary Settlers. International Journal of Environmental Research and Public Health. 2015; 12(12):15449-15458. https://doi.org/10.3390/ijerph121214996
Chicago/Turabian StyleZhang, Yuankai, Xunfei Yin, Zhijiang He, Xiangjun Zhang, Yang Wen, and Hongchen Wang. 2015. "Modeling the Activated Sludge—Thickening Process in Secondary Settlers" International Journal of Environmental Research and Public Health 12, no. 12: 15449-15458. https://doi.org/10.3390/ijerph121214996