Investigating the influence of multiple particle properties on the separation of ultrafine particles via enhanced froth flotation


Investigating the influence of multiple particle properties on the separation of ultrafine particles via enhanced froth flotation

Sandbrink, J.; Rudolph, M.

One of the most important techniques to separate valuable minerals from unwanted gangue is froth flotation. It is an efficient process for particles with sizes ranging from 10 µm to 200 µm and its main separation feature is the difference in particle wettabilities. As particles are getting finer, existing flotation techniques need to be adapted and improved in order to have an efficient separation. For that reason, this project, which is part of the German research foundation priority programme DFG-SPP 2045 “MehrDimPart”, aims at developing a method for the separation of ultrafine particles based on multiple particle properties, such as size, morphology or surface energy.
A particle system consisting of ultrafine size fractions of glass particles as the valuable material and magnetite as the gangue material is used for this study. The wettability of the glass particles is modified via an esterification reaction using alcohols with differing chain length and the resulting wettability states are analysed using inverse gas chromatography as well as analytic particle solvent extraction. Information on the particle size and shape are obtained via a combination of laser diffraction and microscopic analysis. The technique of flow cytometry is introduced for multidimensional particle characterization, as it allows for simultaneous size and shape analysis. Additionally, information on the particle wettability can be obtained by fluorescent marking of particles with dyes. All flotation tests are carried out in batch mode using a novel flotation apparatus, specifically designed for the flotation of ultrafine particles by combining advantages from machine-type froth flotation and column flotation and the separation process is evaluated using multidimensional partition curves.
This investigation will help to further understand how certain particle properties influence flotation, as well as other separation processes. In this way, the separation of ultrafine particles will be more efficient, which will play an important role in the recycling of secondary materials.

Keywords: ultrafine particles; multidimensional separation; flotation; particle characterization; partition curves

  • Lecture (Conference)
    9th World Congress on Particle Technology, 18.-22.09.2022, Madrid, Spanien

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Publ.-Id: 35087