Date Available
5-10-2026
Year of Publication
2025
Document Type
Doctoral Dissertation
Degree Name
Doctor of Philosophy (PhD)
College
Engineering
Department/School/Program
Mining Engineering
Faculty
Rick Honaker
Faculty
John Groppo
Faculty
Steven Schafrik
Abstract
The advent of HydroFloat™ technology, developed by Eriez Manufacturing, marks a significant milestone in the evolution of the mineral processing industry, particularly for the coarse particle flotation by shifting the limits, well-known as the “Elephant Curve.” As the industry strives to process lower-grade ores with higher tonnages for financial reasons, the significance of processing coarse particles through HydroFloat™ technology becomes increasingly critical.
This approach offers substantial benefits by potentially reducing energy consumption within grinding circuits, making it a key solution in enhancing efficiency and cost-effectiveness. This study presents a comprehensive review of the existing literature, laying a solid foundation by elucidating the fundamental principles of the technology, along with rigorous parametric and optimization studies form the core of the investigation, examining the effects of various parameters such as fluidization water flowrate, air flowrate, collector dosage and conditioning time on the efficiency and optimization. Therefore, this study focuses on the development and validation of a standard testing procedure for an 82-mm diameter laboratory scale HydroFloat™ unit designed and manufactured by Eriez, providing a reproducible framework for evaluating coarse particle flotation performance and aiming to reduce sample size requirements for assessing the potential of the HydroFloat™ technology to treat a given ore which results can be compared. The findings from this study not only deepen the understanding of HydroFloat™ technology but also serve as a crucial guide for practitioners aiming to enhance the efficiency and effectiveness of coarse particle flotation technologies.
A comprehensive parametric investigation was conducted using two chalcopyrite-bearing massive sulfide ores to establish a robust experimental methodology. The effects of key process parameters—including fluidization water flow rate, air flow rate, collector type and dosage, frother dosage, and conditioning time—were systematically examined to optimize flotation conditions. The results demonstrated that fluidization water flow rate and collector chemistry play a critical role in enhancing coarse particle recovery, with AERO 3501 exhibiting superior performance over AERO 8989. Baseline conditions were established, with 2.2 L/min fluidization water and 50 g/t collector dosage achieving up to 75% copper recovery for the KUC-I ore, while the coarser KUC-II ore required increased fluidization water (3.5 L/min) and a higher collector dosage (90 g/t). Statistical analysis confirmed the reproducibility of results, demonstrating that 1.5–2 kg of HydroFloat™ feed material is sufficient for feasibility studies, with 2–3 kg recommended for pre-bed preparation.
This standardized methodology was then applied to evaluate the performance of various flotation reagents and to investigate the influence of fine particle content on coarse particle recovery. Further investigations assessed the flotation performance of various commercial and novel dithiocarbonate (DTC) and dithiophosphate (DTP) collectors. The experimental DTC 11250 collector exhibited the highest overall copper recovery (78.3%) and concentrate grade (1.91%), outperforming both AERO 350 and AERO 3501. Adsorption studies corroborated these findings, indicating that DTC 11250 displayed a higher relative adsorption intensity, which directly correlated with improved flotation performance. These results underscore the importance of reagent selection in optimizing coarse particle recovery and warrant further exploration of collector adsorption mechanisms.
Additionally, the impact of fine particle content on coarse particle recovery was examined to address challenges related to particle interactions in the HydroFloat™ system. A split-feed conditioning approach, wherein fines (-53 µm) and coarse fractions were conditioned separately and subsequently recombined, resulted in improved recoveries compared to conventional direct conditioning. However, at finer cut sizes (-75 µm), increased surface area and elevated total surface energy appeared to limit coarse particle recovery due to enhanced fine particle interactions and reduced bubble attachment efficiency. The results suggest that managing fine particle content is critical for maximizing HydroFloat™ flotation efficiency, with implications for industrial classifier performance and reagent optimization.
This research establishes a standardized procedure for evaluating HydroFloat™ technology at the laboratory scale, offering a reproducible methodology that facilitates performance comparisons across different ores and reagent systems. The findings contribute to the broader understanding of coarse particle flotation mechanisms and provide valuable insights for optimizing flotation circuits in industrial applications.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2025.50
Funding Information
Eriez Manufacturing and Syensqo Chemical supported this study in 2022.2023,2024, and 2025.
Recommended Citation
Ozsoy, Yucel, "ENHANCED SEPARATION PERFORMANCE FOR FRACTIONALLY LIBERATED MATERIALS USING THE HYDROFLOAT™ PROCESS TECHNOLOGY" (2025). Theses and Dissertations--Mining Engineering. 89.
https://uknowledge.uky.edu/mng_etds/89
