**4. Conclusions**

This research aims to analyse the implications of physical conditions of the feedwell on the rheological properties of the underflow of flocculated clay-based tailings in seawater. The mixing intensity was related to the structural characteristics of the aggregates, and the outcomes were linked to the yield stress of the flocculated pulp sediment. Stronger agitations cause a more significant breaking of bonds between the particle/aggregate networks that make up the slurry, before the sedimentation process. This induces the aggregate structures to be more fragile and open; then, higher mixing intensity leads to lower yield stress values. In this context, at a fixed mixing rate, the yield stress presented a seemingly exponential increase over the fractal dimension. Additionally, a direct relationship between the yield stress and the settling rate was found since both parameters depend on the structural characteristic of the particle aggregates. The outcomes provided in this study are of interest to the copper mining industry, especially those that use seawater in their operations.

**Author Contributions:** All of the authors contributed to analysing the results and writing the paper.

**Funding:** This research was funded by Conicyt Fondecyt 11171036 and Centro CRHIAM Project Conicyt/Fondap/15130015.

**Acknowledgments:** Ricardo I. Jeldres thanks Conicyt Fondecyt 11171036 and Centro CRHIAM Project Conicyt/Fondap/15130015. The authors are grateful for the contribution of the Scientific Equipment Unit-MAINI of the Universidad Católica del Norte for supporting the experimental tests. Pedro Robles thanks the Pontificia Universidad Católica de Valparaíso for the support provided.

**Conflicts of Interest:** The authors declare no conflict of interest.

### **References**

1. Kane, J.C.; La Mer, V.K.; Linford, H.B. The effect of solid content on the adsorption and flocculation behavior of silica suspensions. *J. Phys. Chem.* **1964**, *68*, 3539–3544. [CrossRef]


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