Dr. Martin Rudolph
Head of the Processing Department

Phone: +49 0351 260 - 4410


Further Links


Department of Processing

Flotation Cell in the Freiberg Laboratory ©Copyright: HZDR/Frank Schinski

Flotation Cell in the Freiberg Laboratory, Photo: HZDR/Frank Schinski

While the global metal content in deposits decreases, more and more ores are characterized by valuable minerals that are finely distributed and bound in rather small particles (< 100 µm). For the raw materials industry, however, processing several billion tons of ore per year is becoming a major technical challenge.

Therefore, the Department of Processing is concerned with enhancing classical flotation techniques and at the same time develops holistic processing concepts in order to exploit the increasingly complex mineral resources such as complex ore deposits or tailings.

The department also utilizes innovative biological technologies by closely working together with the Biotechnology Department, which develops new methods for extracting and processing metals from primary and secondary resources using microorganisms as well as their metabolic products.

Research Fields

Oil-based Ultrafine Flotation

By using oil-based sorting methods, the Processing Department aims at increasing the se­paration efficiency of particle systems with a high amount of ultra-fine particles.

Multidimensional Ultrafine Flotation

The entrainment of undesired ultrafine gangue particles into the froth reduces the quality of the flotation product. A new technology for the multidimensional se­paration of ultrafine particles is being investigated.

Atomic Force Microscopy for Particle Surfaces

Atomic Force Microscopy enables to measure surface characteristics on a micro and nano scale or to analyse micro processes such as particle-bubble interactions in order to improve process models

Investigating Interfacial Phenomena

Precisely characterizing phase properties at microscopic scale, helps to improve the general understanding of interfacial phenomena. A bet­ter understanding will thus help to improve to control flotation processes.

Hydrodynamics within the Flotation Cell

The Processing Department investigates hydrodynamic processes with the goal to increase the collision frequency between bubbles and particles - especially the ultra-fine fractions – and thus to improve the beneficiation of valuable minerals.

Impact of Water Quality on the Flotation Performance

A new model is being created, that predicts the flotation performance as a function of the changing water composition in order to improve the efficiency of processing procedures.

Resource Efficiency through Modelling

On the basis of the geometallurgical approach empirical and fundamental models are being combined in order to produce appropriate predictive and flexible froth flotation simulations using particle as well as flotation ­information.