A Resolved Simulation Approach to Investigate the Separation Behavior in Solid Bowl Centrifuges Using Material Functions
Abstract
:1. Introduction
2. Method
2.1. General Approach
- The gas phase was neglected.
- The approach was limited to the transport of an average particle size whereby the particles were of the same shape and density.
- Both the particles and the liquid were incompressible.
- There was no mass transfer between the components.
- The settling velocity in the apparatus as well as consolidation and sediment transport depend only on the solids volume fraction. Thereby, the influence of the disperse phase and continuous phase and their interactions are modeled by material functions.
- Wall effects were not taken into account.
2.2. Transport of Solid Phase
2.3. Rheological Behavior
3. Results and Discussion
3.1. Comparison with Literature
3.2. Comparison with Experiments
3.2.1. Hindrance Function
3.2.2. Consolidation Function
3.2.3. Findings
3.3. Transfer of the Methodology to Rotating Decanter Screw Element
3.3.1. Geometry and Parameters
3.3.2. Sediment Formation and Flow Conditions
4. Conclusions and Outlook
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Material Properties | |
Density difference | 1700 kg m−3 |
Gel point | |
Material Functions | |
Stokes settling velocity | 1 × 10−4 m s−1 |
Settling exponent | 5 |
Consolidation parameter | 900 |
Consolidation parameter | 7 |
Material Properties | |
Density of the liquid | 1000 kg m−3 |
Dynamic viscosity of the liquid | 1 mPa s |
Density of the solids | 2700 kg m −3 |
Mean particle size | 4 × 10−5 m |
Material Functions | |
Gel point | |
Settling exponent | |
Consolidation parameter | 700 |
Consolidation parameter | 7 |
Process Conditions | |
Initial solids volume fraction | |
Rotational speed n | 2000 rpm |
Differential speed | 10 rpm |
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Baust, H.K.; Hammerich, S.; König, H.; Nirschl, H.; Gleiß, M. A Resolved Simulation Approach to Investigate the Separation Behavior in Solid Bowl Centrifuges Using Material Functions. Separations 2022, 9, 248. https://doi.org/10.3390/separations9090248
Baust HK, Hammerich S, König H, Nirschl H, Gleiß M. A Resolved Simulation Approach to Investigate the Separation Behavior in Solid Bowl Centrifuges Using Material Functions. Separations. 2022; 9(9):248. https://doi.org/10.3390/separations9090248
Chicago/Turabian StyleBaust, Helene Katharina, Simon Hammerich, Hartmut König, Hermann Nirschl, and Marco Gleiß. 2022. "A Resolved Simulation Approach to Investigate the Separation Behavior in Solid Bowl Centrifuges Using Material Functions" Separations 9, no. 9: 248. https://doi.org/10.3390/separations9090248