## 1 Introduction  
Overexploitation of water sources in hyper-arid and arid regions, such as northern Chile, southern Peru, northern China, and parts of Africa, Asia, and Australia, has led to water scarcity, necessitating the search for new sources and better water management practices [1; 2; 3]. While mining globally uses a relatively small amount of water, it can be a significant consumer at the local level. In Chilean mining, approximately 3% of the total available water is utilized, drawn from three primary sources: continental water, seawater, and recirculated water. Continental water is sourced from underground aquifers, lakes, rivers, and wetlands. Seawater undergoes desalination by private entities and is then pumped to mining sites. Data from COCHILCO indicate that the use of continental water in 2022 decreased by 10.8% compared to its use in 2018 [4]. However, the use of this source has come under scrutiny due to its dwindling availability and increasing demand, prompting a shift towards seawater usage in mining operations over the years. Regarding continental water usage in mining, we can identify five primary areas: concentration processes, which emerge as the most water-intensive, consuming 74.3% of available resources; hydrometallurgy, which follows closely behind at 10.2%; the mining phase, which accounts for over 5.6% of water usage; smelting and refining operations, which utilize 3.6% of the total water volume; and other uses, including supply to third parties, accounting for 6.3% [4]. In all these cases, the reuse of water is a priority for the sustainability of the process. However, the recirculated water, used to minimize the consumption of freshwater, typically carries lower quality, containing dissolved waste and colloidal particles, such as dissolved components and especially clays, generating a negative effect on the process [5]. Clays are usually dispersed in mineral slurries as ultrafine particles, creating conditions for the slurry to behave as a non-Newtonian fluid that affects the entire mineral processing chain. In particular, the efficiency of flotation of copper sulfides is severely impacted by clay minerals. The long-term stability of clay colloidal particles in the electrolyte presents significant challenges in mineral processing due to the low shear strength of discarded solids in mineral operations, such as tailings, reduced consolidation and strength gain over time, and difficulties in water recovery during subsequent ore processing. These types of minerals can be separated by sedimentation and/or flotation processes, but ultrafine clays pose a challenge for mineral processing due to physical properties such as particle size, shape, and density. Parameters such as those mentioned are critical for understanding the behavior of these particles in saline solutions like seawater. The presence of soluble salts can disrupt the stability of clay colloids, enhancing sedimentation and consolidation, promoting strength gain, and improving water recovery. Increased water salinity improves the volume of froth floating by diminishing settling [6]. Particle weight is the dominant force that governs the behavior of coarse clay particles in suspension, whereas inter-particle forces, due to the small particle size and high specific surface area, primarily dominate the behavior of fine-grained particles. It has been reported that the aggregation rate of nanosized clay particles present in oil sand tailings increases with rising NaCl concentration and that the initial settling rate of oil sand tailings increases with higher pH and/or the presence of divalent cations (Ca\({}^{2+}\) and Mg\({}^{2+}\)) [7]. The presence of clay significantly hampers copper ore flotation, leading to decreased recovery rates and a subsequent decline in concentrate grades. Clays are classified as swelling and non-swelling based on their water-absorption capabilities.