Reducing the Presence of Clusters in Bubble Size Measurements for Gas Dispersion Characterizations
Abstract
:1. Introduction
2. Materials and Methods
3. Results
4. Discussion and Future Work
5. Conclusions
- A new deflecting system that allowed a fraction of the sampled bubbles to be photographed was effective in reducing clusters of bubbles in the visual field. This improvement strongly depended upon the experimental conditions (i.e., frother types and concentrations and superficial gas rates).
- The maximum improvement in the number of bubbles automatically identified was 20% (absolute), using the new deflector. This result corresponded to a relative increase of 38%.
- The new deflecting system led to better performances in the ability to automatically identify bubbles when transitioning from ellipsoidal/ellipsoidal-turbulent regimes (no frother or low frother concentrations) to conditions with an over-agglomeration of bubbles in the visual field (high superficial gas rates and high frother concentrations).
- The new sampling system allowed more bubbles to be automatically identified with no significant differences in the estimated statistical parameters of the bubble size distributions.
Author Contributions
Funding
Conflicts of Interest
Appendix A
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Technique | Threshold | Sensitivity | Edge Threshold |
---|---|---|---|
Solidity | 0.93 | - | - |
Watershed + Solidity | 0.93 | - | - |
Hough | - | 0.80 | 0.66 |
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Vinnett, L.; Urriola, B.; Orellana, F.; Guajardo, C.; Esteban, A. Reducing the Presence of Clusters in Bubble Size Measurements for Gas Dispersion Characterizations. Minerals 2022, 12, 1148. https://doi.org/10.3390/min12091148
Vinnett L, Urriola B, Orellana F, Guajardo C, Esteban A. Reducing the Presence of Clusters in Bubble Size Measurements for Gas Dispersion Characterizations. Minerals. 2022; 12(9):1148. https://doi.org/10.3390/min12091148
Chicago/Turabian StyleVinnett, Luis, Benjamín Urriola, Francisca Orellana, Camila Guajardo, and Alex Esteban. 2022. "Reducing the Presence of Clusters in Bubble Size Measurements for Gas Dispersion Characterizations" Minerals 12, no. 9: 1148. https://doi.org/10.3390/min12091148