Modeling of realistic microstructures on the basis of quantitative mineralogical analyses

Technische Universität Bergakademie Freiberg

Sprache:

Michael Klichowicz

Dr. Michael Klichowicz studierte Maschinenbau an der Technischen Universität Bergakademie Freiberg, wo er sich auf Aufbereitungs-, Spezialtiefbau- und Bergbaumaschinen spezialisierte. Seine Masterarbeit erhielt den Klaus Schönert-Preis des VDMA und wurde von der Stiftung Lausitzer Braunkohle für ihre herausragende Qualität ausgezeichnet. Außerdem wurde Michael Klichowicz vom VDMA als Ingenieur für Aufbereitungsmaschinen für Mineralien und Anlagenbau zertifiziert. Anschließend arbeitete Michael Klichowicz als wissenschaftlicher Mitarbeiter am Institut für Aufbereitungsmaschinen in Freiberg und veröffentlichte seine Dissertation im Jahr 2020. Derzeit ist er Postdoc-Forscher am Institut.

Auf einen?

Expertise

  • Mineral processing
  • Discrete element simulation
  • Microstructure modeling

Interessant für

  • Mineral-processing engineers
  • Mineralogists
  • Geologists
Unsplash/Omar Flores
Michael Klichowicz

Dr. Michael Klichowicz studierte Maschinenbau an der Technischen Universität Bergakademie Freiberg, wo er sich auf Aufbereitungs-, Spezialtiefbau- und Bergbaumaschinen spezialisierte. Seine Masterarbeit erhielt den Klaus Schönert-Preis des VDMA und wurde von der Stiftung Lausitzer Braunkohle für ihre herausragende Qualität ausgezeichnet. Außerdem wurde Michael Klichowicz vom VDMA als Ingenieur für Aufbereitungsmaschinen für Mineralien und Anlagenbau zertifiziert. Anschließend arbeitete Michael Klichowicz als wissenschaftlicher Mitarbeiter am Institut für Aufbereitungsmaschinen in Freiberg und veröffentlichte seine Dissertation im Jahr 2020. Derzeit ist er Postdoc-Forscher am Institut.

Auf einen?

Expertise

  • Mineral processing
  • Discrete element simulation
  • Microstructure modeling

Interessant für

  • Mineral-processing engineers
  • Mineralogists
  • Geologists

Interview

Russell Alt-Haaker
Redakteur

In your dissertation, you look at how to make comminution technology more efficient. What exactly is comminution, and what is it used for?

Michael Klichowicz
schreibt…
Russell Alt-Haaker
Redakteur

In your dissertation, you look at how to make comminution technology more efficient. What exactly is comminution, and what is it used for?

Michael Klichowicz
Doktorand

Comminution is the generic technical term used when materials are intentionally crushed, ground or milled in a technical process. In my thesis, I use the concept in the context of mineral processing. Put simply, it means a lump of ore is broken up. However, the term also describes what happens to an old battery that is shredded for recycling or the milling of active pharmaceutical ingredients for making an ointment. Since it is essential to so many production and recycling processes, almost all man-made things are somehow comminuted before we can buy them as end users.

Russell Alt-Haaker
Redakteur

Your research aims to improve computer simulations of comminution systems based on the discrete element method. Can you explain this method and how it works?

Michael Klichowicz
Doktorand

It is an approach in which the motion of different objects can be simulated mechanistically. It is based on the evaluation of Newton’s laws of motion. The basic principle is to take the current state of each object (e.g. position and velocity) as the basis for calculating where these objects have moved to after a certain period of time. Interactions between the objects, like collisions, can be implemented as additional models so that they affect the states of those objects interacting with each other. We can use this approach to simulate how billiard balls move and collide, for example. With more complex interaction models, however, it is also possible to simulate the interactions between almost any objects—ranging from molecules to galaxies. Furthermore, these discrete elements can also be bonded together, creating arbitrary solid structures. By making such bonds fragile, it is possible to model breakable materials like rock.

Russell Alt-Haaker
Redakteur

You have developed a procedure for creating synthetic microstructures that can be used in effective mineral-processing simulations. To work, it is necessary to characterize real mineral microstructures. Would you shed some light on this procedure known as quantitative microstructure analysis?

Michael Klichowicz
Doktorand

In order to explicitly simulate the fracturing of mineral materials, for example by using the discrete element method with fragile bonds, it is necessary to provide such simulations with the proper information about the mineral materials’ microstructure. To do so, thin or polished sections of the real mineral material are analyzed with polarized light microscopy, which makes it possible to differentiate between the various minerals and grains.
Based on this, you can characterize the real microstructure in question with stereological methods. Specifically, you measure the sections by counting intersection points between the different grains or planimetry. This allows you to calculate parameters that describe the entire microstructure. In contrast to the typical qualitative verbal description of microstructures, which has historically often been used in mineralogy, this procedure is called quantitative microstructural analysis.

Russell Alt-Haaker
Redakteur

In your view, what are some of the most relevant real-world impacts or applications of your research?

Michael Klichowicz
Doktorand

Creating realistic microstructures on the computer, which are then used for further simulations, is far removed from our everyday activities. It is basic research. However, it’s a field of research with a huge impact on our life, since almost all man-made things undergo some kind of comminution in production or recycling. For example, it is estimated that around 3% of all energy consumption in the world is due just to grinding and crushing minerals. Making these processes more efficient can reduce that energy footprint significantly. What’s more, there are some applications where correctly understanding the influence of the microstructure is relevant to us. This can include the concrete in the pylons of bridges we have to cross every day to get to work or the liberation of rare earth elements, which are essential to countless technologies, ranging from light-emitting diodes to permanent magnets in the motors of electric cars. 

Keywords

Mineral, processing, comminution, fracture behavior, ore processing, discrete element method, microstructure, fracture propagation, mineral microstructure, computer simulation, quantitative microstructure analysis, sustainability

Abstract

This research aims to make it possible to use realistic mineral microstructures in simulations of mineral processing. In particular, comminution processes, such as the crushing and grinding of raw mineral materials, are highly affected by the mineral microstructure, since the texture and structure of the many grains and their micromechanical properties determine the macroscopic fracture behavior.

To illustrate this, consider a mineral material that essentially consists of grains of two different mineral phases, such as quartz and feldspar. If the micromechanical properties of these two phases are different, this will likely have an impact on the macroscopic fracture behavior. Assuming that the grains of one of the minerals break at lower loads, it is likely that a crack through a stone of that material will spread through the weaker grains. In fact, this is an important property for ore processing. In order to extract valuable minerals from an ore, it is important to liberate them from the commercially worthless material in which they are found. For this, it is essential to know and understand how the material breaks at grain-size level.

To be able to simulate this breakage, it is important to use realistic models of the mineral microstructures. This study demonstrates how such realistic two-dimensional microstructures can be generated on the computer based on quantitative microstructural analysis. Furthermore, the study shows how these synthetic microstructures can then be incorporated into the well-established discrete element method, where the breakage of mineral material can be simulated at grain-size level.

Zitiervorschlag

Klichowicz, Michael. Modeling of realistic microstructures on the basis of quantitative mineralogical analyses. Berlin: DUZ Verlags- und Medienhaus, 2020.

Repository

tubaf.qucosa.de

Identifikatoren

978-3-96037-342-1

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