Change search
Refine search result
12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Einfluss verschiedener Parameter auf die Verdichtbarkeit und Festigkeit gestampfter Kohlekuchen2008Conference paper (Other academic)
  • 2.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    Stamped coal cakes in cokemaking technology Part 1 - A parameter study on stampability2009In: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 36, no 5, p. 321-326Article in journal (Refereed)
  • 3.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Stamped coal cakes in cokemaking technology Part 2 - The investigation of cake strength2009In: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 36, no 5, p. 327-332Article in journal (Refereed)
  • 4.
    Alakangas, Lena
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sandström, Åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Martinsson, Olof
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hällström, Lina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Project: Improve Resource Efficiency and Minimize Environmental Footprint2016Other (Other (popular science, discussion, etc.))
    Abstract [en]

    The REMinE project is organized in five work packages that comprise: detailedcharacterization and risk assessment of the mine wastes selected (WP2), identification of new processing methods for mine waste (WP3), characterization and risk assessment of the remaining residuals (WP4), outlining business opportunities and environmental impact in a conceptual model for sustainable mining (WP5). The project comprises case studies of historical mine wastes from three different European countries, namely Portugal, Romania and Sweden. The interdisciplinary research collaboration in this project is innovative in the sense that separation of minerals and extraction of metals not only are basedon technical and economic gain but also considers the environmental perspective.

  • 5.
    Andersson, Anton
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Ahmed, Hesham
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Samuelsson, Caisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Characterization and Upgrading of a Low Zinc-Containing and Fine Blast Furnace Sludge: A Multi-Objective Analysis2017In: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 57, no 2, p. 262-271Article in journal (Refereed)
  • 6.
    Bielig, Tina
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Methodology for the process based acquisition and assessment of non-intended outputs in the mining industry2007In: CLEAN - Soil, Air, Water, ISSN 1863-0650, E-ISSN 1863-0669, Vol. 35, no 4, p. 370-377Article in journal (Refereed)
    Abstract [en]

    For the activities of the mining industry land, equipment, material, and energy are used. During operation material and energy flows such as overburden, dead rock, tailings, wastewater, exhaust air, dust, energy, abrasion, coolant and lubricant losses, are released. These released material and energy flows are nearly always without value for the raw material supply chain as they are not production targets. Instead, they have negative effects on the economy and ecology and are, therefore, referred to as non-intended. The knowledge of the quantities and qualities of these non-intended outputs as a function of the processes and their parameters is the basis for technical and economical measures. A methodology for the acquisition and assessment of the material and energy flows in the mining industry was developed and tested at the Technical University Berlin, Germany. For that purpose and based on a system analysis in different mines, all relevant material and energy flows were assigned to individual processes. Causal relationships, possible interactions, quantities, and qualities were examined as functions of system parameters. Finally, a technical and economic evaluation was performed.

  • 7.
    Chelgani, Saeed Chehreh
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Parian, Mehdi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Semsari, Parisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Ghorbani, Yousef
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    A comparative study on the effects of dry and wet grinding on mineral flotation separation: a review2019In: Journal of Materials Research and Technology, ISSN 2238-7854, Vol. 8, no 5, p. 5004-5011Article, review/survey (Refereed)
    Abstract [en]

    Water scarcity dictates to limit the use of water in ore processing plants particularly in arid regions. Since wet grinding is the most common method for particle size reduction and mineral liberation, there is a lack of understanding about the effects of dry grinding on downstream separation processes such as flotation. This manuscript compiles various effects of dry grinding on flotation and compares them with wet grinding. Dry grinding consumes higher energy and produces wider particle size distributions compared with wet grinding. It significantly decreases the rate of media consumption and liner wear; thus, the contamination of pulp for flotation separation is lower after dry grinding. Surface roughness, particle agglomeration, and surface oxidation are higher in dry grinding than wet grinding, which all these effects on the flotation process. Moreover, dry ground samples in the pulp phase correlate with higher Eh and dissolved oxygen concentration. Therefore, dry grinding can alter the floatability of minerals. This review thoroughly assesses various approaches for flotation separation of different minerals, which have been drily ground, and provides perspectives for further future investigations.

  • 8.
    Gruhn, Günter
    et al.
    TU Hamburg-Harburg.
    Rosenkranz, Jan
    Multiobjective Approach for Energy Conservation and Environmental Protection on Process Plants1995Conference paper (Other academic)
  • 9.
    Gruhn, Günter
    et al.
    TU Hamburg-Harburg.
    Rosenkranz, Jan
    Werter, Joachim
    TU Hamburg-Harburg.
    Toebermann, J.-Christian
    TU Hamburg-Harburg.
    Development of an object-oriented simulation system for complex solids processes1997In: Computers and Chemical Engineering, ISSN 0098-1354, E-ISSN 1873-4375, Vol. 21, p. S187-S192Article in journal (Refereed)
    Abstract [en]

    This contribution focuses on the development of SolidSim, an object-oriented, sequential-modular simulator adopted to the special requirements of steady-state solids processes. The conceptual design of the program system and implementational issues concerning process streams and unit operation models are outlined. Results from first test runs for different solids processes are presented.

  • 10.
    Guntoro, Pratama Istiadi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Ghorbani, Yousef
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Koch, Pierre-Henri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    X-ray Microcomputed Tomography (µCT) for Mineral Characterization: A Review of Data Analysis Methods2019In: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 9, no 3, article id 183Article in journal (Refereed)
    Abstract [en]

    The main advantage of X-ray microcomputed tomography (µCT) as a non-destructive imaging tool lies in its ability to analyze the three-dimensional (3D) interior of a sample, therefore eliminating the stereological error exhibited in conventional two-dimensional (2D) image analysis. Coupled with the correct data analysis methods, µCT allows extraction of textural and mineralogical information from ore samples. This study provides a comprehensive overview on the available and potentially useful data analysis methods for processing 3D datasets acquired with laboratory µCT systems. Our study indicates that there is a rapid development of new techniques and algorithms capable of processing µCT datasets, but application of such techniques is often sample-specific. Several methods that have been successfully implemented for other similar materials (soils, aggregates, rocks) were also found to have the potential to be applied in mineral characterization. The main challenge in establishing a µCT system as a mineral characterization tool lies in the computational expenses of processing the large 3D dataset. Additionally, since most of the µCT dataset is based on the attenuation of the minerals, the presence of minerals with similar attenuations limits the capability of µCT in mineral segmentation. Further development on the data processing workflow is needed to accelerate the breakthrough of µCT as an analytical tool in mineral characterization.

  • 11.
    Guntoro, Pratama Istiadi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Ghorbani, Yousef
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Use of X-ray Micro-computed Tomography (µCT) for 3-D Ore Characterization: A Turning Point in Process Mineralogy2019Conference paper (Refereed)
    Abstract [en]

    In recent years, automated mineralogy has become an essential enabling technology in the field of process mineralogy, allowing better understanding between mineralogy and the beneficiation process. Recent developments in X-ray micro-computed tomography (μCT) as a non-destructive technique have indicated great potential to become the next automated mineralogy technique. μCT’s main advantage lies in its ability to allow 3-D monitoring of internal structure of the ore at resolutions down to a few hundred nanometers, thereby eliminating the stereological error encountered in conventional 2-D analysis. Driven by the technological and computational progress, the technique is continuously developing as an analysis tool in ore characterization and subsequently it foreseen thatμCT will become an indispensable technique in the field of process mineralogy. Although several software tools have been developed for processing μCT dataset, but the main challenge in μCT data analysis remains in the mineralogical analysis, where μCT data often lacks contrast between mineral phases, making segmentation difficult. In this paper, an overview of some current applications of μCT in ore characterization is reviewed, alongside with it potential implications to process mineralogy. It also describes the current limitations of its application and concludes with outlook on the future development of 3-D ore characterization.

  • 12.
    Guntoro, Pratama Istiadi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Tiu, Glacialle
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ghorbani, Yousef
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lund, Cecilia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Application of machine learning techniques in mineral phase segmentation for X-ray microcomputed tomography (µCT) data2019In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 142, article id 105882Article in journal (Refereed)
    Abstract [en]

    X-ray microcomputed tomography (µCT) offers a non-destructive three-dimensional analysis of ores but its application in mineralogical analysis and mineral segmentation is relatively limited. In this study, the application of machine learning techniques for segmenting mineral phases in a µCT dataset is presented. Various techniques were implemented, including unsupervised classification as well as grayscale-based and feature-based supervised classification. A feature matching method was used to register the back-scattered electron (BSE) mineral map to its corresponding µCT slice, allowing automatic annotation of minerals in the µCT slice to create training data for the classifiers. Unsupervised classification produced satisfactory results in terms of segmenting between amphibole, plagioclase, and sulfide phases. However, the technique was not able to differentiate between sulfide phases in the case of chalcopyrite and pyrite. Using supervised classification, around 50–60% of the chalcopyrite and 97–99% of pyrite were correctly identified. Feature based classification was found to have a poorer sensitivity to chalcopyrite, but produced a better result in segmenting between the mineral grains, as it operates based on voxel regions instead of individual voxels. The mineralogical results from the 3D µCT data showed considerable difference compared to the BSE mineral map, indicating stereological error exhibited in the latter analysis. The main limitation of this approach lies in the dataset itself, in which there was a significant overlap in grayscale values between chalcopyrite and pyrite, therefore highly limiting the classifier accuracy.

  • 13.
    Koch, Pierre-Henri
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    How to Build a Process Model in a Geometallurgical Program?2015In: Mineral Resources in a Sustainable World / [ed] A.S. Andre-Mayer; M. Cathelineau; P. Muchez; E. Pirard; S. Sindern, 2015, p. 1419-1422Conference paper (Refereed)
    Abstract [en]

    This work presents a literature review on ways to acquire relevant experimental data for the process model of a geometallurgical program. It identifies the needs in several unit models and proposes ideas for future developments

  • 14.
    Koch, Pierre-Henri
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lund, Cecilia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Automated drill core mineralogical characterization method for texture classification and modal mineralogy estimation for geometallurgy2019In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 136, p. 99-109Article in journal (Refereed)
    Abstract [en]

    In geometallurgy, a process model operating at the mineral liberation level needs quantitative textural information about the ore. The utilization of this information within process modeling and simulation will increase the quality of the predictions.

    In this study, descriptors derived from color images and machine learning algorithms are used to group drill core intervals into textural classes and estimate mineral maps by automatic pixel classification. Different descriptors and classifiers are compared, based on their accuracy and capacity to be automated. Integration of the classifier approach with mineral processing simulation is also demonstrated. The quantification of textural information for mineral processing simulation introduced new tools towards an integrated information flow from the drill cores to a geometallurgical model.

    The approach has been verified by comparing traditional geological texture classification against the one obtained from automatic methods. The tested drill cores are sampled from a porphyry copper deposit located in Northern Sweden.

  • 15.
    Koch, Pierre-Henri
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Texture-based liberation models for comminution2017In: Konferens i Mineralteknik 2017: Luleå 7-8 februari 2017, Luleå, 2017, p. 83-96Conference paper (Other academic)
    Abstract [en]

    The relation between breakage mechanisms and liberation is critical in mineral processing. Recent studies underline the importance of texture in liberation. This study reviews relevant liberation models and proposes a new method for generating particles using image processing algorithms. One new texture simulation method and its relevance for liberation simulation is also introduced.

  • 16.
    Kuyumcu, Halit Z.
    et al.
    Department of Mechanical Process Engineering & Solids Processing, Technical University Berlin.
    Abel, Frank
    Department of Mechanical Process Engineering & Solids Processing, Technical University Berlin.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Analyses of the coal densification behaviour and the coal cake stability within the stamped charge coke making operation2011In: Conference in Minerals Engineering 2011: Luleå 8-9 February 2011 / [ed] Johanna Alatalo, Luleå: Luleå tekniska universitet, 2011, p. 123-137Conference paper (Other academic)
  • 17.
    Kuyumcu, Halit Z.
    et al.
    Department for Mechanical Process Engineering & Solids Processing, Technical University Berlin.
    Rosenkranz, Jan
    Investigation of fluff separation from granulated waste plastics to be used in blast furnace operation2009In: Conference in minerals proceedings: Luleå / [ed] Johanna Alatalo, Luleå, 2009Conference paper (Other academic)
  • 18.
    Kuyumcu, Halit Z.
    et al.
    Department for Mechanical Process Engineering & Solids Processing, Technical University Berlin.
    Rosenkranz, Jan
    Investigation om fluff separation from granulated waste plastics to be used in blst furnace operation2009In: Conference in minerals proceedings: Luleå, 3-4 februari 2009 / [ed] Johanna Alatalo, Luleå, 2009Conference paper (Other academic)
  • 19.
    Kuyumcu, Halit Z.
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Investigations on the densification of particulate materials by stamping2006Conference paper (Refereed)
  • 20.
    Kuyumcu, Halit Z.
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Untersuchungen zur Verdichtung von Steinkohlen durch Stampfen2005Conference paper (Other academic)
  • 21.
    Kuyumcu, Halit Z.
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Untersuchungen zur Verdichtung von Steinkohlen durch Stampfen2006In: Stahl und Eisen (1881), ISSN 0340-4803, Vol. 126, no 1, p. 41-47Article in journal (Other academic)
  • 22.
    Kuyumcu, Halit Z.
    et al.
    Technische Universität Berlin.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Abel, Frank
    Technische Universität Berlin.
    Behavior of coking coals within stamp charge operation2010In: Conference proceedings: International Coal Preparation Congress 2010 : XVI ICPC 2010 ; [Lexington, KY, April 25 - 29, 2010] / [ed] Rick Q. Honaker, Littleton, Colo.: Society for Mining, Metalurgy and Exploration, 2010, p. 947-956Conference paper (Refereed)
  • 23.
    Kuyumcu, Halit Z.
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Abel, Frank
    TU Berlin.
    Verdichten von Steinkohle durch Stampfen für den Einsatz bei der Verkokung2004In: Schüttgut, ISSN 0946-7939, Vol. 10, no 3, p. 222-225Article in journal (Other academic)
  • 24.
    Kuyumcu, Halit Z.
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Wilck, Stefan
    TU Berlin.
    Application of the microwave technology for the processing of iron hydroxysulphates recovered from lignite acid mine water2008Conference paper (Refereed)
  • 25.
    Kuyumcu, Halit Z.
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Wilck, Stefan
    TU Berlin.
    Processing of Iron Hydroxysulphates recovered from Lignite Mine Acid Water by means of Microwave Technology2007Conference paper (Other academic)
  • 26.
    Lamberg, Pertti
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Parian, Mehdi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mwanga, Abdul
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mineralogical Mass Balancing of Industrial Circuits by Combining XRF and XRD Analyses2013In: Proceedings Conference in Minerals Engineering 2013 / [ed] Jan Rosenkranz; Tommy Karlkvist, Luleå: Luleå tekniska universitet, 2013, p. 105-116Conference paper (Other academic)
    Abstract [en]

    Mineralogical information forms a vital basis for designing, diagnosing and optimizing mineral processing circuits. Often modal mineralogical mass balance (i.e. mass balance on mineral grades) is adequate; i.e. liberation data is not required. In analysing mineral grades in process samples automated mineralogy (SEM based image analysis) is mostly used. As this method is tedious, slow, and costly, and has some limitation, an alternative technique was developed by combining quantitative X-ray diffraction (XRD) and chemical assays by X-ray fluorescence (XRF). A case study on magnetic separation test is presented. Method has potential for an automatized off-line technique for providing mineralogical mass balance in majority of mineral processing plants.

  • 27.
    Lamberg, Pertti
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Systematic Diagnosis of Flotation Circuit Performance Based on Process Mineralogical Methods2014Conference paper (Refereed)
    Abstract [en]

    Operators of industrial flotation circuits experience every now and then situations where the processing performance of the plant is poorer than expected. Usually this leads to a continual and useless debate whether the problems are related to the ore properties or to the process. This paper presents a systematic approach to problem diagnosis using an analysis method based on process mineralogical tools. The diagnosis first requires a base-case analysis where the key process streams of the circuit have been sampled and studied by applying mineral process simulation in combination with the particle tracking technique, i.e. by balancing mixed particles of different mineral composition. This creates the base model of the flotation process against which the deviations are compared. Common performance problems are divided in three groups, which refer to recovery, grade and impurity. The mineralogical reason can in each case be a change in (i) mineral assemblage, (ii) head grade, (iii) liberation degree, or (iv) mineral associations. The diagnosis progresses by classifying the indications and by ruling out causes by means of process mineralogical methods. The procedure is presented as a diagnosis chart with suggestions for how to cure the problem. To illustrate the application of the method several practical examples are presented.

  • 28.
    Lamberg, Pertti
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Wanhainen, Christina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lund, Cecilia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Minz, Friederike
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mwanga, Abdul
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Parian, Mehdi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Building a Geometallurgical Model in Iron Ores using a Mineralogical Approach with Liberation Data2013In: Geomet13: The Second AusIMM International Geometallurgy Conference 2013 / [ed] Simon Dominy, Parkville, Victoria: The Australasian Institute of Mining and Metallurgy, 2013, p. 317-324Conference paper (Refereed)
    Abstract [en]

    A geometallurgical model is currently built in two different ways. The first and the most common way relies on geometallurgical testing, where a large number of samples are analysed for metallurgical response using small-scale laboratory tests, eg Davis tube testing. The second, mineralogical approach focuses on collecting mineralogical information over the orebody and building the metallurgical model based on mineralogy. At Luleå University of Technology,Sweden, the latter method has been adopted and taken further in four ongoing PhD studies. The geological model gives modal composition by the help of element-to-mineral conversion and Rietveld X-ray diffraction. Texturally, the orebody is divided into different archetypes, and liberation measurements for each of them are carried out in processing fineness using IncaMineral, a SEM-based technique. The grindability and liberation spectrum of any given geological unit (sample, ore block, domain) are extrapolated from the archetypes. The process model is taken into a liberation level by mass balancing selected metallurgical tests using the particle tracking technique. The approach is general and can be applied to any type of ores. Examples of ongoing studies on iron and massive sulfide ores are given.

  • 29.
    Lindberg, Therese
    et al.
    LKAB.
    Mattsby, Charlotte
    LKAB.
    Niiranen, Kari
    LKAB.
    Taavoniku, Krister
    LKAB.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Hallberg, Dan
    LKAB.
    Fredriksson, Andreas
    LKAB.
    Geometallurgy@LKAB2013In: Proceedings Conference in Minerals Engineering 2013 / [ed] Jan Rosenkranz; Tommy Karlkvist, Luleå: Luleå tekniska universitet, 2013, p. 125-136Conference paper (Other academic)
    Abstract [en]

    The area of geometallurgy is in its context not entirely new and LKAB has for ages worked according to the idea “minerals to products”, but the development especially on the instrumental analysis side the last ten years has made a geometallurgy a feasible area today. LKAB’s idea is to work quite broad, with internal educations, an active working process in ongoing projects, together with external parties (such as Luleå University of Technology), with PhD-projects and an upgrading on the instrumental side at LKAB R&D. This paper is a summary about the concept geometallurgy at LKAB and some of the actions within the framework of Geometallurgy@LKAB.

  • 30.
    Malm, Lisa
    et al.
    Boliden Mineral, Department of Process Technology.
    Kindstedt Danielsson, Ann-Sofi
    RISE – Research Institutes of Sweden AB, Surface, Process and Pharmaceutical Development.
    Sand, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Ymén, Ingvar
    RISE – Research Institutes of Sweden AB, Surface, Process and Pharmaceutical Development.
    Application of Dynamic Vapor Sorption for evaluation of hydrophobicity in industrial-scale froth flotation2018In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 127, p. 305-311Article in journal (Refereed)
    Abstract [en]

    The particle surface properties are essential for understanding froth flotation, particularly for the evaluation of various chemical or reagent effects.

    Dynamic Vapor Sorption (DVS) is used in the pharmaceutical industry for the evaluation of surface properties and has to the knowledge of the authors not been used for applications in mineral processing. This paper describes an evaluation of industrial ore samples using DVS.

    Four samples (feed, CuPb concentrate, Cu concentrate and Pb concentrate) from each of the Cu – Pb flotation processes in the Boliden and Garpenberg concentrators, Sweden, were analyzed by DVS in order to investigate if this technique could be used to estimate differences in their hydrophilicity. The DVS measures the water uptake as a function of the relative humidity (%RH) at constant temperature.

    For both series of four samples, it was found that the DVS-data are in precise agreement with the flotation theory on hydrophobicity (indicated by differences in water uptake). The feed material, without any collectors, adsorbed more water compared to the CuPb bulk concentrate, which in turn adsorbed more water than the Cu concentrate. The lead concentrate on the other hand, which had been depressed by dichromate and should be more hydrophilic, showed a higher adsorbance of water than that of the CuPb concentrate.

    The repeated measurements of three sub samples from one of the ore samples gave a mean value and an estimated standard deviation of 0.13 ± 0.01%. This shows that the method gives highly reproducible results and that the differences between the samples had high significance. This also shows that the DVS method can serve as a useful complement to traditionally used contact angle or capillary absorption-based measurement methods, especially when screening for new flotation reagents on industrial ore samples.

  • 31.
    Malm, Lisa
    et al.
    Boliden Mineral, Department of Process Technology, Boliden, Sweden.
    Sand, Anders
    Boliden Mineral, Department of Process Technology, Boliden, Sweden.
    Bolin, Nils-Johan
    Boliden Mineral, Department of Process Technology, Boliden, Sweden.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Ymén, Ingvar
    RISE- Research Institutes of Sweden AB, Bioscience and Materials/Surface, Process and Formulation, Sweden.
    Dynamic vapor sorption measurement and identification of mineral species in industrial-scale flotation cell samples2019In: Powder Technology, ISSN 0032-5910, E-ISSN 1873-328X, Vol. 356, p. 1016-1023Article in journal (Refereed)
    Abstract [en]

    In order to understand flotation performance in industrial-scale, it is of relevance to understand the surface properties and mineral species of materials contained in the various parts of the cell. In this work XRPD X-Ray Powder Diffraction) and DVS (Dynamic Vapor Sorption) were used to characterise the different minerals and the wettability of the sample collected at different depths in an industrial scale flotation cell.

    DVS is a novel technique for wettability measurement in mineral processing, of higher robustness and reproducibility compared to the Washburn technique.

    In the turbulent zone of the cell, the wettability properties are relatively similar, and decreases in the froth and concentrate. Differences in radial position were only found near the froth phase close to the shaft of the agitator.

    The main finding was that wettability information obtained by DVS could be correlated with mineral composition and particle size distribution.

  • 32.
    Malm, Lisa
    et al.
    Boliden Mineral Ab.
    Sand, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Bolin, Nils-Johan
    Boliden Mineral Ab.
    Spatial Variations of Pulp Properties in Flotation: Implications for Optimizing Cell Design and Performance2016In: Proceedings of International Mineral Processing Congress, Quebec, Canada, ISBN, 2016Conference paper (Refereed)
  • 33.
    Mulenshi, Jane
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Khavari, Pourya
    Chelgani, Saeed Chehreh
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Characterization and beneficiation options for tungsten recovery from Yxsjöberg historical ore tailings2019In: Processes, ISSN 2227-9717, Vol. 7, no 12, article id 895Article in journal (Refereed)
    Abstract [en]

    Repositories of historical tungsten mining tailings pose environmental risks, but are also potential resources for valuable metals. They still contain large tonnages of useful minerals and metals, reflecting the inefficient extraction methods and/or low metal prices at the time they were mined. The focus of this study is to evaluate the technical viability of reprocessing the tailings to recover some of the contained valuable minerals and metals, as well as reducing the negative environmental impact associated with the tailings. Geometallurgical studies were conducted on drill core samples taken from the Smaltjärnen tailings repository of the closed Yxsjöberg tungsten mine, Sweden. The collected samples were characterized physically, chemically, and mineralogically. Knelson concentrator dry low- and high-intensity magnetic separation methods were tested as potential beneficiation methods. The tailings are dominated by the −600 to +149 µm particles. The highest concentration of tungsten (W) was 0.22% WO3. Using a Knelson concentrator, scheelite (main W mineral) recovery was enhanced, with 75 wt.% tungsten recovered in the 34 wt.% heavy concentrate. Only 1.0 wt.% sulphur (S) reported to the non-magnetic fraction. Based on the findings, a methodology and a preliminary process flowsheet for reprocessing the tailings is proposed.

  • 34.
    Mulenshi, Jane
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Khavari, Pourya
    Chelgani, Saeed Chehreh
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Feasibility of gravity and magnetic separation for Yxsjöberg historical tungsten ore tailings2019Conference paper (Refereed)
    Abstract [en]

    Repositories of historical tailings (HT) pose environmental risks but could also become new resources for valuable metals. This is because relatively high minerals and metals content characterize them due to less efficient extraction methods and/or relatively low metal prices at the time. In this investigation, geometallurgical studies were conducted by collecting drill core samples (DCS) from the Smaltjärnen tailings repository in Yxsjöberg, Sweden. The collected DCS were from the main layers of the longest drill core, and were characterized physically (color, texture, moisture content and particle size distribution) and chemically (elemental composition and distribution, and mineralogical composition). The characterization of DCS indicated that the tailings mass distribution was high in the coarser particle size fraction of +149 μm. Tungsten (W) and Copper (Cu) were the metals of interest with highest concentrations being 0.22 %WO3 and 0.11 %Cu. Feasible physical separation methods selected were Knelson concentrator, LIMS and HIMS, based on the knowledge from literature, tailings characteristics, and assessment of processes from which the Yxsjöberg HT were produced. Using the Knelson concentrator, the recovery of scheelite, which is the main W mineral, was enhanced, with 75 wt.% tungsten recovered in the 34 wt.% of concentrate produced. In magnetic separation, sulphur (S) was mostly recovered in the ferromagnetic and paramagnetic fractions with only 1.0 wt.% in the non-magnetic fraction, meaning pyrrhotite, the main Fe-sulphide mineral in the HT responsible for AMD, was separated to the desired magnetic fractions of the LIMS and HIMS. These results are fundamental in the development of methods for separation of valuable minerals from these HT in order to produce an inert and environmentally safe residue.

  • 35.
    Mulenshi, Jane
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Khavari, Pourya
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Characterization and feasible physical separation methods for Yxsjöberg historical tungsten ore tailings2019Conference paper (Other academic)
    Abstract [en]

    Relatively high minerals and metals content characterize historical tailings due to less efficient extraction methods and/or relatively low metal prices at the time. Repositories of such tailings pose environmental risks but could also become metals and minerals resources. An example of such tailings is the Yxsjöberg historical tungsten ore tailings in the Smaltjärnen tailings repository in Sweden.   

    The Smaltjärnen tailings repository was sampled by collecting drill core samples from different locations. The collected drill core samples were characterized physically (colour, texture, moisture content and particle size distribution) and chemically (elemental composition and distribution, and mineralogical composition). Feasible physical separation methods (magnetic and gravity separation) were pre-selected based on the tailings characteristics and the knowledge of processes from which the Yxsjöberg historical tailings were produced.

    In this paper, results from three drill cores each representing a different location on the tailings repository are presented. The tailings mass distribution was high in the coarser particle size fractions of +300 µm and +149 µm.  Tungsten (W) and Copper (Cu) were the metals of interest with one location having higher concentrations than the other two at 0.20 %WO3 and 0.14 %Cu. Sulphur (S) was recovered in the magnetic fractions of the LIMS and HIMS. Using the Knelson concentrator, W recovery was enhanced. These results are fundamental in the development of methods for separation of minerals and extraction of metals of interest from the historical tailings in order to leave behind an inert and environmentally safe residue.

  • 36.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Comminution test method using small drill core samples2015In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 72, p. 129-139Article in journal (Refereed)
    Abstract [en]

    Comminution tests aim to measure the comminution properties of ore samples to be used in designing and sizing the grinding circuit and to study the variation within an ore body. In the geometallurgy context this information is essential for creating a proper resource model for production planning and management and process control of the resource’s exploitation before and during production.Standard grindability tests require at least 10 kg of ore sample, which is quite a lot at early project stages. This paper deals with the development of a method for mapping the variability of comminution properties with very small sample amounts. The method uses a lab-scale jaw crusher, standard laboratory sieves and a small laboratory tumbling mill equipped with a gross energy measurement device. The method was evaluated against rock mechanics tests and standard Bond grindability test. Within this approach textural information from drill cores is used as a sample classification criterion.Experimental results show that a sample of approximate 220 g already provides relevant information about the grindability behavior of iron ores at 19% mill fillings and 91% fraction of the critical mill speed. The gross energy measured is then used to calculate an equivalent grinding energy. This equivalent energy is further used for predicting the variations in throughput for a given deposit and process.Liberation properties of the ore connected to grindability elaborates energy required for grinding and significances of it when deciding to move to higher grinding energy considering the improvement of liberation of the desired mineral. However, high energy significantly enhanced the degree of liberation of magnetite and is expected to improve the concentrate grade after downstream treatment. The higher the magnetite content the better is the liberability of magnetite and the lower the energy required to liberate the desired mineral. Liberability of magnetite is also affected by texture classes containing low magnetite content. A methodology that combines this information has been developed as a practical framework of geometallurgical modeling and simulation in order to manage technical and economic exploitation of resource at early, project stages and during mining operations.

  • 37.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Liberability: A new approach for measuring ore comminution behavior2014Conference paper (Other academic)
    Abstract [en]

    Crushability and grindability are traditionally used to describe the material properties in comminution. These parameters neglect the main objective of ore comminution, the mineral liberation and therefore information is incomplete. A new concept called liberability: the easiness of mineral liberation in comminution is introduced to fill the gap. Establishing a liberability map of a deposit requires grindability tests and liberation measurements for the grinding product. The liberability curve shows the degree of liberation of the mineral against grinding energy and offers better baseline for resource optimization than the grindability curve. A case study with a magnetite iron ore from Malmberget, northern Sweden, shows that certain shortcuts can be applied to keep the experimental effort reasonable which is important, particularly when applying the liberability in a geometallurgical program. In Malmberget the liberability is depending on the grade and grain size of magnetite. A significant difference between grindability and liberability can be observed.

  • 38.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Parian, Mehdi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Comminution modeling using mineralogical properties of iron ores2017In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 111, p. 182-197Article in journal (Refereed)
    Abstract [en]

    Comminution modeling aims to predict the size and liberation distribution of mineral particles and the required comminution energy. The current state-of-the-art comminution models provide a calculation of neither particle size distribution, grinding energy and throughput dependency with neither a broad understanding of how the mineral grade varies by size nor the liberation distribution of the product. The underlying breakage mechanisms affect the liberation of mineral grains and are dependent on modal mineralogy and mineral texture (micro structure). It has also been a challenge to model comminution systems to predict the optimal energy and size for better mineral liberation because of the variability of the mineral particle properties i.e. grains arrangement and composition. A detailed mineralogical study was carried out in order to broaden the understanding of the nature and distribution of comminuted particles in a ball mill product. Focusing on iron ore samples the study showed how the particle breakage rate decreases when the particles reach the grain size of the main mineral component. Below that size, comminution does not increase mineral liberation and therefore in most of the cases passing over that boundary is only a waste of energy. The study involving iron ores from Malmberget and Kiruna, Northern Sweden, showed that certain shortcuts can be applied to empirically model the mineral liberation distribution of the particles in a ball mill based on the mineral grade-by-size pattern from a geometallurgical program. In Malmberget and Kiruna the mineral grade-by-size pattern is depending on the mineral distribution and grain size of gangue as well as magnetite or hematite minerals. A significant difference between mineral breakage of the same grade and gangue minerals can be observed due to texture differences.

  • 39.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    A Comminution Model for Linking Size Reduction with Energy and Mineral Liberation2015Conference paper (Refereed)
    Abstract [en]

    Traditionally comminution models are used to predict size reduction and the energy required for that. For better control of energy and quality of concentrate grade in subsequent concentration processes also the liberation of the minerals has to be considered. Mechanical forces are used to break the bonds of the mineral matrix of composite particle into mineral phases.Mineral composition and texture (i.e. the grain size) have been used to predict the breakage properties of an ore but are not fully used to predict the liberation of mineral particles during comminution. For this purpose an integrated breakage model is needed that links the energy used to reduce the size of the mineral particles with the mineral liberation achieved during comminution. Such a liberation model for forecasting the degree of mineral liberation has to be based on mineral texture information.As a novel approach, a liberability curve for various mineral textures has been developed and used to optimize the particle size and energy required for ore comminution. Tests with iron ore samples from the Malmberget mine in Northern Sweden show that, liberation and breakage of the mineral particles are controlled by the grade distribution and grain size of magnetite.

  • 40.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Developing Ore Comminution Test Methods in the Geometallurgical Context2014Conference paper (Other academic)
    Abstract [en]

    Comminution tests are necessary in order to investigate mineral liberation achieved during particle size reduction and the mechanical energy needed for that. Depending on the type of the comminution process and equipment respectively, various test methods have been established in the past. Most of these tests require comparatively large sample amounts and are also costly in terms of time.Within the geometallurgical approach comprehensive information about the ore’s processing properties is required for building a spatial geometallurgical model of a deposit. Comminution behavior has to be quantified when modeling mill capacity and liberation. Providing comminution test methods that are efficient in terms of sample utilization and effort is therefore an essential task.This paper summarizes several different approaches to quantifying ore comminution behavior in the geometallurgical context. The methods examined at Luleå University of Technology comprise linking crushing and grinding characteristics to mineralogical parameters as well as correlating them with geotechnical tests, the down-scaling of standard grindability tests, and the further development of drop weight test methods.

  • 41.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Development and experimental validation of the Geometallurgical Comminution Test (GCT)2017In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 108, p. 109-114Article in journal (Refereed)
    Abstract [en]

    Based on the requirements and available sample amounts in geometallurgical studies of ore variability, a small scale batch grindability test has been developed, the Geometallurgical Comminution Test (GCT). The test requires 220 g of sample material and can be conducted within 2.5–3 h. Test results are evaluated using a modified Bond equation together with a linear correlation factor. The test and evaluation method have been validated against several ore types.

  • 42.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Testing of Ore Comminution Behavior in the Geometallurgical Context: A Review2015In: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 5, no 2, p. 276-297Article in journal (Refereed)
    Abstract [en]

    Comminution tests are an important element in the proper design of orebeneficiation plants. In the past, test work has been conducted for particular representative reference samples. Within geometallurgy the entire ore body is explored in order to further identify the variation within the resource and to establish spatial geometallurgical domains that show the differential response to mineral processing. Setting up a geometallurgical program for an ore deposit requires extensive test work. Methods for testing the comminution behavior must therefore be more efficient in terms of time and cost but also with respect to sample requirements. The integration of the test method into the geometallurgical modeling framework is also important. This paper provides an overview of standard comminution test methods used for the investigation of ore comminution behavior and evaluates their applicability and potential in the geometallurgical context.

  • 43.
    Mwanga, Abdul
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Koch, Pierre-Henri
    Université de Liège.
    Simplified Comminution Test Method for Studying Small Amounts of Ore Samples for Geometallurgical Purposes2013In: Exploration, Resource & Mining Geology Conference 2013 / [ed] Claire Lockyer, Cardiff, Wales, UK: The Australian Institute of Mining and Metallurgy , 2013Conference paper (Refereed)
    Abstract [en]

    Comminution tests aim at measuring the grindability of ore samples to be used in describing the variability within an orebody and designing the grinding circuit. Within the geometallurgical context this information is very important for creating a proper model for production planning,management and control of the resource’s exploitation before and during the production.Standard grindability tests require at least 2 kg of ore sample, which is quite a lot at early project stages and therefore often problematic. This presentation will deal with the development of a method for studying comminution behaviour of materials with very small sample amounts.The method uses a small laboratory tumbling mill equipped with a gross energy measurement device. The method evaluation comprises the correlation between rock mechanical testing and grindability test methods. Within this approach textural information from drill cores is used as a classification criterium.Experimental results show that a sample of approximately 350 g already provides relevant information about the grindability behaviour of iron ores in the range of 45 to 55 per cent solids, based on mill charge. The gross energy measured is then used to calculate an equivalent grinding energy. This equivalent energy is further used for predicting the variations in throughput for a given deposit and process.

  • 44.
    Parian, Mehdi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Möckel, Robert
    Helmholtz-Zentrum Dresden – Rossendorf, Helmholtz Institute Freiberg for Resource Technology, Halsbruecker Straße 34, 09599 Freiberg.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Analysis of mineral grades for geometallurgy: Combined element-to-mineral conversion and quantitative X-ray diffraction2015In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 82, p. 25-35Article in journal (Refereed)
    Abstract [en]

    Knowledge of the grade of valuable elements and its variation is not sufficient for geometallurgy. Minerals define not only the value of the deposit, but also the method of extraction and concentration. A number of methods for obtaining mineral grades were evaluated with a focus on geometallurgical applicability, precision and trueness. For a geometallurgical program, the number of samples to be analyzed is large, therefore a method for obtaining mineral grades needs to be cost-efficient, relatively fast, and reliable. Automated mineralogy based on scanning electron microscopy is generally regarded as the most reliable method for analyzing mineral grades. However, the method is time demanding and expensive. Quantitative X-ray diffraction has a relatively high detection limit, 0.5%, while the method is not suitable for some base and precious metal ores, it still provides significant details on gangue mineral grades. The application of the element-to-mineral conversion has been limited to the simple mineralogy because the number of elements analyzed limits the number of calculable mineral grades. This study investigates a new method for the estimation of mineral grades applicable for geometallurgy by combining both the element-to-mineral conversion method and quantitative X-ray diffraction with Rietveld refinement. The proposed method not only delivers the required turnover for geometallurgy, but also overcomes the shortcomings if quantitative X-ray diffraction or element-to-mineral is used alone

  • 45.
    Parian, Mehdi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Developing a particle-based process model for unit operations of mineral processing: WLIMS2016In: International Journal of Mineral Processing, ISSN 0301-7516, E-ISSN 1879-3525, Vol. 154, p. 53-65Article in journal (Refereed)
    Abstract [en]

    Process models in mineral processing can be classified based on the level of information required from the ore, i.e. the feed stream to the processing plant. Mineral processing models usually require information on total solid flow rate, mineralogical composition and particle size information. The most comprehensive level of mineral processing models is the particle-based one (liberation level), which gives particle-by-particle information on their mineralogical composition, size, density, shape i.e. all necessary information on the processed material for simulating unit operations. In flowsheet simulation, the major benefit of a particle-based model over other models is that it can be directly linked to any other particle-based unit models in the process simulation. This study aims to develop a unit operation model for a wet low intensity magnetic separator on particle property level. The experimental data was gathered in a plant survey of the KA3 iron ore concentrator of Luossavaara-Kiirunavaara AB in Kiruna. Corresponding feed, concentrate and tailings streams of the primary magnetic separator were sampled, assayed and mass balanced on mineral liberation level. The mass-balanced data showed that the behavior of individual particles in the magnetic separation is depending on their size and composition. The developed model involves a size and composition dependent entrapment parameter and a separation function that depends on the magnetic volume of the particle and the nature of gangue mineral. The model is capable of forecasting the behavior of particles in magnetic separation with the necessary accuracy. This study highlights the benefits that particle-based models in simulation offer whereas lower level process models fail to provide.

  • 46.
    Parian, Mehdi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Process simulations in mineralogy-based geometallurgy of iron ores2018In: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855Article in journal (Refereed)
    Abstract [en]

    Mineral processing simulation models can be classified based on the level that feed stream to the plant and unit models are described. The levels of modelling in this context are: bulk, mineral or element by size, and particle. Particle level modelling and simulation utilises liberation data in the feed stream and is more sensitive to the variations in ore quality, specifically ore texture. In this paper, simulations for two texturally different magnetite ores are demonstrated at different modelling levels. The model parameters were calibrated for current run-of-mine ore and then in the simulation applied directly to the other ore. For the second ore, the simulation results vary between the different levels. This is because, at the bulk level, the model assumes minerals do not change their behaviour if ore texture or grinding fineness are changed. At the mineral by size level, the assumption is that minerals behave identically in each size fraction even if the ore texture changes. At the particle level, the assumption is that similar particles behave in the same way. The particle level approach gives results that are more realistic and it can be used in optimisation, thus finding the most optimal processing way for different geometallurgical domains.

  • 47.
    Parian, Mehdi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Lamberg, Pertti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Using modal composition instead of elemental grades in mineral resource estimate – high quality modal analysis by combining X-ray diffraction and X-ray fluorescence2014Conference paper (Other academic)
  • 48.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Better resource efficiency by improved comminution2012Conference paper (Other academic)
    Abstract [en]

    The comminution stage is usually not only the most energy intensive step within mineral processing plants, but it is also crucial for all subsequent steps in mineral beneficiation. Sufficiently liberating the valuable mineral grains from particles by grinding an ore to finer particle sizes is the key prerequisite for efficient mineral separation in downstream processes. When considering the general trends in processing mineral ores, i.e. towards ores of lower grade, fine grained ores and more complex mineralogy, improved comminution becomes even more relevant in terms of both energy efficiency and utilization of mineral raw materials. For size reduction and liberation various comminution devices of different design and operating principles are available. Their selection and operation is often not optimal due to limited ore characterization. Lack of knowledge with respect to ore texture and mineral associations, this also seen against the backdrop of the variability within an ore body, frequently results in aiming at too fine product particle sizes. Adjusting the breakage mechanism to the texture of a particular ore, based on e.g. advanced electron microscopy or computer tomography analyses, can lead to enhanced liberation already at coarser particle sizes, thus allowing decreasing the size reduction ratio. Selection of the appropriate breakage mechanism or equipment type respectively, does also affect the energy utilization in the downstream processing as certain types of devices particularly support the formation of micro cracks. Inducing micro cracks, partly occurring at the mineral grain boundaries, results in particle weakening and increased liberation and therefore facilitates subsequent grinding and concentrating processes. Design and operating conditions of comminution devices can then be further optimized using advanced modeling and simulation methods. Particle simulations based on computational physics, as the discrete element method or other, allow improving the performance of mills and crushers with respect to energy utilization and wear. Finally improved comminution can also be achieved by process optimization on grinding circuit level as well as process plant level. This comprises the introduction of improved classification methods within comminution circuits but also the pre-concentration by removing liberated gangue already at coarser particle sizes, or by successive separation and size reduction, for instance within staged grinding and flotation.

  • 49.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Liberation of heterogeneous particles2015Conference paper (Other academic)
    Abstract [en]

    Liberation of heterogeneous particles by comminution is the prerequisite for efficient separation in subsequent concentration processes. Consequently, comminution process design and optimization have to be based on the quantitative description of both particle size reduction and liberation during fragmentation. The current status of liberation measurement techniques and modeling approaches is reviewed.

  • 50.
    Rosenkranz, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mineral processing at Luleå University of Technology: meeting the research and educational needs2010In: Conference in Minerals Engineering: Luleå, 2 -3 februari 2010 / [ed] Johanna Alatalo, Luleå tekniska universitet, 2010, p. 1-12Conference paper (Other academic)
    Abstract [en]

    With the start of the new decade the Mineral Processing chair at Luleå University of Technology has been newly appointed. The scientific redirection of the chair includes several of the important topic areas of advanced mineral processing. From process mineralogy via comminution and concentration processes to mathematical modelling and simulation of particulate processing systems, the mineral processing research at Luleå University of Technology is shaped by the interaction of material, process and equipment. This contribution deals with the positioning of the chair in research and education to meet the upcoming needs in a time where the secured supply with high quality commodities is essential

12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf