Eugene Donskoi - Academia.edu (original) (raw)

Papers by Eugene Donskoi

Minerals

To understand and optimise downstream processing of ores, reliable information about mineral abun... more To understand and optimise downstream processing of ores, reliable information about mineral abundance, association, liberation and textural characteristics is needed. Such information can be obtained by using Optical Image Analysis (OIA) in reflected light, which can achieve good discrimination for the majority of minerals. However, reliable automated segmentation of non-opaque minerals, such as quartz, which have reflectivity close to that of the epoxy they are embedded in, has always been problematic. Application of standard thresholding techniques for that purpose typically results in significant misidentifications. This paper presents a sophisticated segmentation mechanism, based on enhanced thresholding of non-opaque minerals developed for Commonwealth Scientific and Industrial Research Organisation’s (CSIRO) Mineral5/Recognition5 OIA software, which significantly improves segmentation in many applications. The method utilises an enhanced image view using an adjusted reflectiv...

Minerals, 2019

Many different approaches have been used in the past to characterise iron ore sinter mineralogy t... more Many different approaches have been used in the past to characterise iron ore sinter mineralogy to predict sinter quality and elucidate the impacts of iron ore characteristics and process variables on the mechanisms of sintering. This paper compares the mineralogy of three sinter samples with binary basicities (mass ratio of CaO/SiO2) between 1.7 and 2.0. The measurement techniques used were optical image analysis and point counting (PC), quantitative X-ray diffraction (QXRD) and two different scanning electron microscopy systems, namely, Quantitative Evaluation of Materials by Scanning Electron Microscopy (QEMSCAN) and TESCAN Integrated Mineral Analyser (TIMA). Each technique has its advantages and disadvantages depending on the objectives of the measurement, with the quantification of crystalline phases, textural relationships between minerals and chemical compositions of the phases covered by the combined results. Some key differences were found between QXRD and the microscopy te...

Fuel

Abstract To better understand the connection between parent coal blend, coke structure, and coke ... more Abstract To better understand the connection between parent coal blend, coke structure, and coke strength novel structural identification and characterisation techniques for processing high resolution optical photomicrographs of coke were developed. Automated segmentation of inert maceral derived components (IMDC) and reactive maceral derived components (RMDC) allowed measurement of a broad range of parameters characterising coke structure. The characterisation included separate characterisation of IMDC and RMDC, IMDC boundaries including calculation of parameters characterising connections between IMDC and RMDC, coke porosity and, separately, IMDC porosity. Several other novel approaches using image analysis software were investigated, such as: • Separation of large porosity objects into individual pores (Separated Pores), • Removal of weak walls and hence potential identification and measurement of Weak Areas, • Identification of nodes (relatively thick agglomerations in the coke structure) and walls (part of the coke matrix connecting nodes), • Measurement of Modified Wall Thickness (when only walls are taken into account), Wall Neck Thickness (weakest points in walls) and Specific Neck Thickness (sum of all necks per unit area). Application of these novel characterisation techniques to a set of coke samples produced a substantial amount of data, which revealed many strong correlations between novel parameters characterising coke structure, and also between these parameters, coke strength indices and parent coal composition. This demonstrated the usefulness of the newly developed characterisation methodologies and gave a significantly improved understanding of coke structure and its connection with coke strength and parent coal blend. It should also be noted that these novel approaches to structural/textural characterisation can be applied to carbonaceous materials other than coke or other structural materials such as sinter, ore, and ceramics.

Minerals Engineering, 2016

Abstract Textural information or information about the presence of porosity, different material o... more Abstract Textural information or information about the presence of porosity, different material or mineral types and their structural arrangement in iron ore is crucial for understanding, predicting and optimising downstream processing performance. Ores with the same chemical and mineral composition may behave very differently during downstream processing due to differences in textural components. To produce a textural description of iron ore, it is preferable to use an automated system to avoid subjectivity and to collect additional information about mineral abundance, liberation and association. CSIRO created a unique dedicated optical image analysis software package for automated textural classification and characterisation of different minerals, sinters and coke. This software, called Mineral4/Recognition4, has been used extensively to collect data for this article. Four case studies of CSIRO research are presented to demonstrate the importance of textural information. • The first example shows that iron ore samples with different texture but similar mineralogy undergo different degrees of assimilation in compact sintering. • The second example shows that empirical modelling of sinter properties was improved considerably after introducing textural information. • The third example demonstrates the application of classification by ore texture to model and optimise hydrocyclone performance. • The last example is an experimental study of ultrasonic treatment of hematitic–goethitic iron ore fines. It demonstrates how the resulting breakdown or deagglomeration of different particles, and the mineral deportment, can be better understood when textural information is also considered. In all cases, the availability of textural information was critical, providing a better prediction of process performance or a deeper understanding of the unit process.

International Journal of Mineral Processing, 2008

A new modelling technique for simulating hydrocyclone performance has been developed, in which pa... more A new modelling technique for simulating hydrocyclone performance has been developed, in which particles in every size fraction of the feed ore are classified based on ore texture type, taking into account that the same ore texture types in every size fraction of the feed ore have similar mineral contents and densities. Mineral tracking by optical image analysis and newly-developed texture classification software was used in this technique to classify the feed ore particles by texture type and to determine the average particle density of each class in every size fraction. Particle density calculations took into account the reduction of porosity with reduction of particle size and the effect of different imaging magnifications for different size fractions. The data obtained about each class in every size fraction was used to create a virtual feed which was input to the hydrocyclone model to simulate the ore processing performance. For model validation, pilot-scale hydrocyclone beneficiation experiments were performed on an iron ore blend, using different hydrocyclone pressures and percent solids in the feed pulp. Model parameters were determined from one set of experimental results and the calibrated model was then used to predict the outcomes of the two subsequent experiments. Comparisons of the model and experimental results are presented and discussed. This new approach enables prediction of the recovery of each mineral and texture type in the products, calculation of the total product iron grade and recovery, and optimisation of the hydrocyclone performance for a given ore.

Abstract. A 3D multi-static SAR imaging system which utilises reflected GPS signals from objects ... more Abstract. A 3D multi-static SAR imaging system which utilises reflected GPS signals from objects on the Earth's surface is described in this paper. The principle of bistatic radar is used to detect movement of, or changes to, the imaged object. The indirect GPS signals are processed by a match filter with the aim of improving the spatial resolution of detection. The measure of spatial resolution of this imaging system is derived, and is confirmed by MATLAB simulation. Several scenarios are considered, for the visible satellite at a given receiver and object location. The scenarios for different satellites are: a) static receiver with two targets which move with the same speed; and b) moving receiver with one static target and one moving target. Simulation results show that the spatial resolution of detection depends on the relative positions of the GPS satellites, the imaged objects and the GPS receiver, as well as their respective velocities.

Sinter quality is a key element for stable blast furnace operation. Sinter strength and reducibil... more Sinter quality is a key element for stable blast furnace operation. Sinter strength and reducibility depend considerably on the mineral composition and associated textural features. During sinter optical image analysis (OIA), it is important to distinguish different morphologies of the same mineral such as primary/secondary hematite, and types of silico-ferrite of calcium and aluminum (SFCA). Standard red, green and blue (RGB) thresholding cannot effectively segment such morphologies one from another. The Commonwealth Scientific Industrial Research Organization’s (CSIRO) OIA software Mineral4/Recognition4 incorporates a unique textural identification module allowing various textures/morphologies of the same mineral to be discriminated. Together with other capabilities of the software, this feature was used for the examination of iron ore sinters where the ability to segment different types of hematite (primary versus secondary), different morphological sub-types of SFCA (platy and p...

Donskoi, Eugene (2000) The mathematical modelling of direct reduction in iron ore/coal composites... more Donskoi, Eugene (2000) The mathematical modelling of direct reduction in iron ore/coal composites including the modelling of coal pyrolysis. PhD thesis, Queensland University of Technology. ... Find a copy in the QUT Library. ... Citation counts are sourced monthly from Scopus ...

European Journal of Mineralogy

Applied Sciences

Optical image analysis is commonly used to characterize different feedstock material for ironmaki... more Optical image analysis is commonly used to characterize different feedstock material for ironmaking, such as iron ore, iron ore sinter, coal and coke. Information is often needed for phases which have the same reflectivity and chemical composition, but different morphology. Such information is usually obtained by manual point counting, which is quite expensive and may not provide consistent results between different petrologists. To perform accurate segmentation of such phases using automated optical image analysis, the software must be able to identify specific textures. CSIRO’s Carbon Steel Futures group has developed an optical image analysis software package called Mineral4/Recognition4, which incorporates a dedicated textural identification module allowing segmentation of such phases. The article discusses the problems associated with segmentation of similar phases in different ironmaking feedstock material using automated optical image analysis and demonstrates successful algo...

Minerals …, 2007

Optical image analysis is a very convenient tool for obtaining comprehensive information about fi... more Optical image analysis is a very convenient tool for obtaining comprehensive information about fine iron ore size fractions. Data can be obtained on mineral abundances, porosity, particle shape and ore textures with a high level of accuracy. A range of techniques has been used to characterise iron ore samples on a particle-by-particle basis. Automatic textural classification of iron ore particles was used to establish classes containing particles with very similar mineral composition and texture. Image analysis coupled with probe analysis and mineral density measurements provided information about the chemical composition and density of each particle class. The combination of these results enabled a ''virtual feed'' to be created, which can be a key input into a beneficiation unit model for predicting its performance. Identification and classification of the textural type of each particle was performed according to the CSIRO-Hamersley Iron Ore Group Classification Scheme. If more detailed classification is needed, further classification can be performed based on dimensional, chemical or mineral criteria, such as the presence of certain minerals in particles or total iron content. Some deficiencies of the current image analysis procedures and their further improvement and automation are also discussed.

Ironmaking & Steelmaking, 2008

These databases contain citations from different subsets of available publications and different ... more These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles ...

The term geometallurgy has numerous definitions but a common understanding is a vital requirement... more The term geometallurgy has numerous definitions but a common understanding is a vital requirement if collaboration is to provide a holistic and integrated approach throughout the value chain. World iron ore production doubled from 2003 to 2010 to reach 2.6 Bt to mainly satisfy the colossal demand from Chinese steel mills for iron ores. The decrease in ore quality, the development of iron ore deposits with new iron ore types, the vast volume of ore mined and the increased requirements from steel makers have created an ever greater need for geometallurgy. In addition to optical microscopy, XRF and XRD analysis, a wide range of methods are now applied to predict downstream processing, including reflectance spectroscopy at the mine, diamond core and drill chips scale; optical image analysis; scanning electron microscopy based platforms such as QEMSCAN™ and MLA for textural and physical information; and electron microprobe and proton-induced X-ray emission for chemical characterisation. In collaboration with the mining industry, CSIRO has combined these methods and built iron ore characterisation and classification systems that are applied through exploration, mining and processing stages to contribute to a better definition of iron ore types and their influence on processed products. This has in turn enhanced production and optimised marketing strategies. Selected iron ore deposits are used as examples for the application of these techniques and highlight the benefit of their use delivers a better understanding of the geometallurgical properties of this economically significant commodity.

Wuhan University Journal of Natural Sciences, 2003

This paper describes a 3D multi-static synthetic aperture radar (SAR) imaging system which utilis... more This paper describes a 3D multi-static synthetic aperture radar (SAR) imaging system which utilises reflected GPS signals from moving objects on the Earth's surface. The GPS satellites, a multi-channel GPS receiver, and its signal detection components, comprise the multi-static SAR system. The principle of bi-static radar is used to model the reflected GPS signals. The movement of a visible GPS satellite serves as a base for a synthetic aperture over an observation time period. Based on this model, a measure of the spatial resolution is derived for terrain imaging applications. As an example, a MATLAB simulation has been carried out in order to detect the movement of imaged objects under the assumption of one static GPS receiver with two targets which move with different speeds. The influence of the visible satellite's position and velocity on the spatial resolution of such a SAR system is discussed. Several parameters, such as the bistatic angle, angles between the velocity vector of satellites, and the position/velocity of the imaged object(s), are considered. Simulation results show that the reflected GPS signals can be used for certain remote sensing applications. By measuring the crosscorrelation of the reflected GPS signal from the terrain and objects on it, the detection of the objects can enjoy a good spatial resolution for the case of moving objects and a moving GPS receiver. Furthermore, the spatial resolution is also related to the selection of visible GPS satellites with respect to their azimuths, elevations and velocities. This

IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477), 2000

ABSTRACT First Page of the Article

IEEE International Geoscience and Remote Sensing Symposium, 2000

ABSTRACT In this paper we describe the concept of a bistatic SAR system which involves a purpose ... more ABSTRACT In this paper we describe the concept of a bistatic SAR system which involves a purpose built stationary ground based receiver but which utilizes existing or proposed low earth orbit satellite (LEOS) communication systems, such as Globalstar or ICO as the transmitting signal sources. In general, such a system has a 3-D configuration (in contrast to the 2-D bistatic SAR systems examined previously in the literature). We analyse this system. With earth observation applications in mind, we characterize quantitatively the 2-D resolving capability within the ground plane. This is demonstrated via a meaningful simulation.

Textural information or information about the presence of porosity, different material or mineral... more Textural information or information about the presence of porosity, different material or mineral types and their structural arrangement in iron ore is crucial for understanding, predicting and optimising downstream processing performance. Ores with the same chemical and mineral composition may behave very differently during downstream processing due to differences in textural components.
To produce a textural description of iron ore, it is preferable to use an automated system to avoid subjectivity and to collect additional information about mineral abundance, liberation and association. CSIRO created a unique dedicated optical image analysis software package for automated textural classification and characterisation of different minerals, sinters and coke. This software, called Mineral4/Recognition4, has been used extensively to collect data for this article.
Four case studies of CSIRO research are presented to demonstrate the importance of textural information.
• The first example shows that iron ore samples with different texture but similar mineralogy undergo different degrees of assimilation in compact sintering.
• The second example shows that empirical modelling of sinter properties was improved considerably after introducing textural information.
• The third example demonstrates the application of classification by ore texture to model and optimise hydrocyclone performance.
• The last example is an experimental study of ultrasonic treatment of hematitic-goethitic iron ore fines. It demonstrates how the resulting breakdown or deagglomeration of different particles, and the mineral deportment, can be better understood when textural information is also considered.
In all cases, the availability of textural information was critical, providing a better prediction of process performance or a deeper understanding of the unit process.