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By Steinar L. Ellefmo, Thomas Kuhn

The deep-sea ocean floor offers a great potential for mineral resources. The evaluation of these resources is both time consuming and costly and require as any resource evaluation data; geodata. The collection of hard data, physical samples, is of course preferred because the associated uncertainty is low. However, the collection of soft data or image derived data can offer a valuable supplement. In this paper image derived nodule uncertain abundance data from an area in the Pacific is utilized. Implementing these uncertain data improves the estimation when the quality of the estimation is measured using the classification indicators like the kriging standard deviation, the relative prediction error, the slope of regression and the weight of the mean. It is concluded that uncertain data is better than no data. INTRODUCTION The deep-sea offers vast mineral resources (Cathles (2011), Hannington et al. (2011), Hannington (2013), Singer (2014)). A mineral resource can according to increasing geological confidence be classified as an inferred, an indicated or a measured resource. The classification is performed by a competent- or qualified person and is dependent on the amount, quality and characteristic of available geodata. The competent person must have at least five years of experience relevant to both the style of mineralisation, the type of deposit and the performed task. Typical examples of a “task” is for example resource estimation and classification or planning- and execution of exploration activities and presentations of the results. The competent person must also be a member or a fellow of a professional organisation and thereby be bound by reporting code (-s) that defines minimum standards, recommendations and guidelines for public reporting.

Jan 1, 2018

By Ronald C. Schimmel

In 2006, the Corus IJmuiden pellet plant produced approximately 4.6 mln tonnes of pellets. Corus IJmuiden is about to increase its pig iron production to 6.4 mln tonne HM per annum. The burden of the Corus IJmuiden blast furnaces consists of approximately 50% high basicity sinter and 50% acid pellets, both produced in-house. To enable an increased iron production, the capacity of the pellet plant needs to be raised to 5.0 mln tonne per annum. The capacity is increased by modifications to the plant layout, which were implemented during the 2006 cold maintenance stop. In addition, the composition of the ore blends is optimised to gain productivity.

May 1, 2007

By M. Cross

INTRODUCTION The results of the Japanese dissective investigations have [l-4] transformed our understanding of how the blast furnace operates. These studies revealed an internal structure of the furnace burden with five main zones, as illustrated in Figure 1. In the granular zone the charged material retains its structure whereas in the cohesive zone the iron ore particles are at advanced stages of reduction and form a semi-molten mass with a relatively high flow resistance. In the active coke zone molten iron and slag flow through a matrix of loosely packed coke. The raceway is a relatively small void space generated by displacement of coke due to the hot blast momentum, whilst the hearth is packed with coke, slag and molten iron. [ ] It is now well appreciated that furnace control is largely achieved and maintained by using the burden charge distribution to determine the gas glow distribution within the furnace and, hence, the shape and extent of the cohesive zone. In fact, Wakayama et a1 [5] of Nippon Steel Corporation state that optimum furnace operation is synonomous with the formation of a desirable cohesive zone shape, which in turn is almost solely determined by the burden charge distribution and its mechanical properties [6]. Much of the development work on operating furnaces since the dissective investigations has been oriented towards the identification of external furnace measures which reliably predict the shape of the cohesive zone. Currently the most popular measures are top gas temperature, velocity and CO/CO, ratio profiles [5]. More recently pressure distributions as evaluated from a series of wall measurements down the height of the furnace are also being utilised [7] to identify the position and shape of the cohesive zone. A great deal of emphasis has been placed upon achieving a consistent quality in the burden charge materials, establishing a suitable set of operating conditions and only making changes when forced to, ie., the operation for some reason moves outside a desired operating range or the production requirements change. Operational control schemes based upon this philosophy (eg., Kawasaki's GO-STOP system [8]) have been remarkably successful at achieving both high production rates and relatively low fuel costs. Mathematical models have long been used as tools to assist in the analysis of the blast furnace process. Although, the models have been useful in post-operative analysis and for identifying trends, etc., they have not proved reliable for detailed design criteria or as the basis for effective control schemes. Such mathematical models have moved from simple statistical correlation, through overall and stagewise heat-and-mass balance calcu-

Jan 1, 1984

By Z. T. Bieniawski

After many significant advances in mining, including development of sophisticated methods for strata characterization and numerical modeling analyses, the engineering design process in mining strata control is as primitive as it was two decades ago. Yet, major advances in design methodologies have occurred in other branches of engineering. Is creative design in mining a myth only? Are we deluding ourselves when we talk about innovative mining design of today? Did you know that most design experts are often unaware of their own decision-making processes? This paper explores the methodology of creative engineering design as a new recognized discipline.

Jan 1, 1987

By K. V. Raj, C. A. Berry, A. T. Weakley, A. L. Miller, P. R. Griffiths, D. A. Parks

Diesel particulate matter (DPM) has been classified as a carcinogen to humans by the International Agency for Research on Cancer. As a result of its potential carcinogenic nature, DPM exposure is regulated by the Mine Safety and Health Administration. Currently, diesel emissions in the workplace are monitored by collecting the aerosol onto filters, which are then sent to a laboratory for thermal-optical analysis using the NIOSH method 5040. This process can take days or even weeks, and workers can potentially be exposed to excessive levels of DPM before the problem is identified. Moreover, the delay involved in getting the loaded filter to the lab inevitably means the loss of some of the more volatile organic carbon. To remedy this delay, researchers from the National Institute for Occupational Safety and Health are seeking to develop a field-portable, real-time method for measuring elemental and organic carbons in DPM aerosols. In the current study, the use of mid-infrared spectrometry was investigated. It is believed that mid-infrared spectroscopy is more suitable for use in a real-time field-portable device than thermo-optical analysis methods. This article presents a method for measuring organic carbon (OC) and elemental carbon (EC) in DPM for a broad range of OC/EC ratios. The method has been successfully applied to laboratory-generated and mine samples.

By K. V. Raj, C. A. Berry, A. T. Weakley, A. L. Miller, P. R. Griffiths, D. A. Parks

Diesel particulate matter (DPM) has been classified as a carcinogen to humans by the International Agency for Research on Cancer. As a result of its potential carcinogenic nature, DPM exposure is regulated by the Mine Safety and Health Administration. Currently, diesel emissions in the workplace are monitored by collecting the aerosol onto filters, which are then sent to a laboratory for thermal-optical analysis using the NIOSH method 5040. This process can take days or even weeks, and workers can potentially be exposed to excessive levels of DPM before the problem is identified. Moreover, the delay involved in getting the loaded filter to the lab inevitably means the loss of some of the more volatile organic carbon. To remedy this delay, researchers from the National Institute for Occupational Safety and Health are seeking to develop a field-portable, real-time method for measuring elemental and organic carbons in DPM aerosols. In the current study, the use of mid-infrared spectrometry was investigated. It is believed that mid-infrared spectroscopy is more suitable for use in a real-time field-portable device than thermo-optical analysis methods. This article presents a method for measuring organic carbon (OC) and elemental carbon (EC) in DPM for a broad range of OC/EC ratios. The method has been successfully applied to laboratory-generated and mine samples.

By M. S. Klima

Proper analysis of washability data can lead to the development of a maximum yield coal preparation plant flow sheet. Simulations, as simple as spreadsheet mass and water balancing, are important in examining yield maximization and middlings liberation. Key to such attribute tracking flow sheet simulations is the distribution model, expressing the probability of a species reporting to the product stream. There are many such models in the literature. This paper examines a functional form that can represent or fit most of the proposed distribution functions.

Jan 1, 1997

By H. Mulder, M. C. Bekker

The principal objective of this investigation was to conduct a thorough literature review on the status of project readiness mechanisms, tools, techniques, and frameworks for mining projects. The review aimed at identifying common readiness evaluation criteria as well as potential shortcomings that prevent the establishment of a generalizable project readiness index. The literature review included a general overview of capital project performances and the importance of project readiness assessments to improve project delivery success. The study then progressed towards literature involving mining projects and how this differs from infrastructure and industrial project assessments. The paper concludes by summarizing the current state of mining project readiness assessments, the unique and differentiating factors to be considered, and suggests recommendations towards the development of generalizable readiness assessment criteria for mining projects.

Sep 1, 2022

By C. A. Pickles

Microwave processing is a relatively new technology that has been successfully applied in a number of industries. However, in the field of metal extraction, there is a paucity of success, despite considerable hype in the early years. Increased reaction rates, lowered reaction temperatures and higher energy efficiencies were some of the advantages claimed. Even with over almost two decades of research and some pilot plant studies, microwave metal extraction remains essentially a laboratory technique. In this paper, the research performed over the last few decades will be reviewed and some reasons for the lack of success in developing microwave metal extraction processes will be discussed. Based on the knowledge gained from these experiences, a more informed view of microwave heating can lead to the realization that there is still some untapped potential for this heating technique in metal extraction processes.

By Gianni Shena, Francesco Montanari

"Recent improvements in the resolution of X-ray computed tomography (CT) make it a promising alternative to traditional time consuming, error prone laboratory procedures for mineral liberation analysis, such as heavy liquid fractioning and measurements on polished sections. All indications are that in a few years CT will be well-established in many laboratories as a rapid technique for accurate liberation studies. In this scenario it would be able to provide liberation spectra or washability data in tens of minutes following sampling. However, although CT is a fast evolving technology, its on-line application is unlikely in the foreseeable future.Dual-energy (DE) radiography is another X-ray technique originating from non-destructive evaluation (NDE) and medical fields, which allows retrieval of the volumetric content of valuable components from two-phase particles in a fraction of second. Two radiographic images at different X-ray energies of a single particle or a monolayer of particles are taken in short time sequence. The thickness of the two phases is calculated particle by particle by image subtraction, whereupon particle grades can be derived. The development of the method for on-line applications requires the presentation of non-overlapping particles in the gap in the X-ray source detector measurement couple. Straightforward extension of the principle to multiphase systems is not possible. The paper reviews the state of the art of these two techniques as applied to mineral liberation problems."

Jan 1, 2003

By M Yahyaei, P Knights, M S. Kizil, J Qu

Digital Twins (DTs) are transforming business operations across many industries through their accurate representations of physical entities enabled by IoT technologies.

Sep 1, 2024

By A J. Morrison, M Yahyaei, J S. Siong, J Wang, K Runge

The flotation cells used to upgrade ultrafine metallurgical coal (-250 µm) are usually poorly controlled leading to unnecessary loss of combustibles from the flotation system. This is mainly because coal flotation cells are typically controlled for process stability rather than optimisation of flotation performance. This is especially true for a flotation device commonly used in coal applications in Australia – the Jameson Cell. This then provides an opportunity to improve the flotation performance by shifting from a stabilising control strategy to a proactive optimising control strategy. For an optimising control strategy, the control system will require a means of relating and then measuring in real-time, the effect of changing operating conditions on the coal flotation performance. Hence, the major aim of this work is to propose a possible model-informed process control strategy that could be used for real-time performance optimisation. In this study, industrial site work was conducted on an industrial-scaled Jameson Cell at a Coal Handling and Preparation Plant (CHPP) in Central Queensland, Australia where superficial gas velocity was controlled to six different levels. At the same time, other process variables such as froth depth and flotation feed properties were measured. The empirical models developed from this study suggested that combustible recovery is a function of superficial gas velocity, froth depth, feed solid content and feed ash content and that a peak in combustible recovery existed as a function of superficial gas velocity. This led to the development of a model-informed control strategy that aimed to maximise the combustible recovery by determining and then operating the cell at the superficial gas velocity at which the peak occurs. This peak superficial gas velocity was found to be only a function of feed solid content. Based on these findings it would seem possible to operate a Jameson cell at peak performance by online measurement of feed solid content, prediction of the optimum superficial gas velocity and stabilising control to maintain operation at that superficial gas velocity set point. The development of this modelinformed control strategy can serve as a basis for the development of a more sophisticated modelpredictive control (MPC) system. However, more work will need to be done to improve the predictivity of the combustible recovery model by measuring and modelling performance over a wider range of operating conditions.

Aug 24, 2022

By A. W. Dickerson

Following on from many years of research aimed at improving the effectiveness of truck haulage operations in mines operated by BHP Minerals, BHP Research developed a concept for an Innovative Large Mining Truck, (ILMT) which has the potential to significantly improve the cost effectiveness of rear dump mining trucks. The ILMT concept reduces the empty vehicle weight dramatically, greatly reduces unequal rear tyre loading and improves ride and handling characteristics. The concept has been taken to the "proof of concept" prototype truck stage with the cooperative efforts of BHP Coal, BHP Research, Liebherr Mining Truck, Inc., Liebherr-Australia and Birrana Engineering. Testing of the prototype truck commenced at a coal mine in Queensland, Australia during May 1996. Preliminary results from the testing program are very encouraging. Expectations are being met and in some cases exceeded.

Jan 1, 1997

Historical Background. South Africa's industrial history began with the discovery of gold and diamonds during the last century, and the mining industry was the first chief component of our technological development. During the past six decades, quantum leaps were made in other fields, too, when other industries and research bodies such as Escom, NDC, Iscor, Sasol, Foskor, Alusaf, Mintek, cs I R, SA B S, and A E C were established. These meaningful additions have two outstanding characteristics. Firstly, they were linked mainly to primary activities such as energy and minerals and, secondly, their establishment was to a large extent due to the driving force of individuals such as Van der Bijl, Van Eck, Rossouw, Schonland, and Roux, rather than to impersonal government policy. Encouraging signs of the evolution of such policy has emerged during the past few years.

Jan 1, 1989

By Peter N. Holtham, Geoffrey J. Lyman, Matthew S. Brennan, Vijay Subramanian, Rui X. Rong, Tim Napier-Munn

Studies of the dense medium and classifying cyclone have been conducted using the Fluent computational fluid dynamics code. Experimental measurements of the segregation of medium in a DM cyclone by gamma-ray tomography and the performance of a novel classifying cyclone design have been used to test and interpret the 3D CFD predictions. The predictions of the CFD models were generally plausible, though more work is required to incorporate turbulent mixing of the slurry in the cyclone. The benefits of the novel cyclone design were explained by the model in terms of conditions favouring reduction of short-circuiting at the vortex finder, and the removal of the air core from the wall at the apex. Work is continuing.

Jan 1, 2003

By Kam Ng

For bridges or buildings that may be subjected to large vertical and lateral loads, drilled shafts offer an economic foundation solution. While the current drilled shaft design practice is considered adequate, introducing a performance-based approach to designing the drilled shafts will make their design more cost-effective and produce more dependable response. This concept was examined using analysis of 41 drilled shaft load test data from several states. This process identified the challenge with the lack of information from the Osterberg (O-cell) load test method to characterize the full top load-displacement response. When a typical single O-cell is utilized in a drilled shaft test, depending on the location of the O-cell and the geomaterials present along and beneath the shaft, the load test result typically quantifies either the side resistance or end bearing reaching the ultimate load-displacement curve but not both components. This limitation hinders the determination of a suitable shaft resistance as a function of a target top displacement. To overcome this challenge, an improved procedure is proposed for establishing the full load-displacement curve based on data gathered from one O-cell. The method will be presented in the paper for three different cases (i.e., side resistance reaches the ultimate during the test, end bearing reaches the ultimate during the test, and neither components reach the ultimate values). Because it allows the characterization of the full load-displacement curve, the proposed procedure will allow performance-based design of drilled shafts with due consideration to settlement while satisfying the Load and Resistance Factor Design.

Jan 1, 2013

By M. Sukhram

This paper presents a technique to determine the direction of velocity in liquid aluminum (Al) by measuring the temperature distribution within a cylindrical rod while it is inserted into the flow. The heating pattern of the rod is a result of the interaction of the thermal fields of the rod with the liquid Al. This interaction freezes aluminum onto the cylinder in a characteristic pattern and as a result the temperature response within the rod also follows a distinctive heating pattern. Monitoring the temperature within the cylindrical rod as a function of spatial and temporal coordinates, the direction of velocity can be inferred. Experimental research work involving liquid Al was conducted at the University of Toronto using the Revolving Liquid Metal Tank (RLMT). The RLMT is a resistance furnace which can hold up to 50kg of liquid Al. In this RLMT tangential velocities up to 0.35m1s can be generated. Experimental data for different superheat and magnitude of velocity demonstrate that the sensor records different heating patterns under different fluid flow conditions. Using the transient temperature information, the direction of velocity of the molten Al flow field can be detected.

Jan 1, 2011

By K. Iturralde

The topic of this article is the automation and robotization in refurbishment processes of industrial buildings. The need to mold these production spaces is quite universal. Particularly in the regions with a high industrial development and with a lack of buildable land, there is a need to convert this kind of spaces into an improved production system. The latest developments can be a useful tool for achieving a more efficient way of reforming this type of construction. On the one hand we have the digital or computerized 3D Laser Scanning (Computer Aided Measurement) that allows an accurate 3D modeling of the entire building. On the other hand, the project management using BIM (Building Information Modeling) could provide an easy design of each of the elements of the refurbishment. Finally, through the production of construction elements using robotics as jig or for CNC (Computer Numerical Control) we achieve a neat production of each element. How can be all those technologies applied in the refurbishment or expansion of industrial buildings? The research takes a first approach and analyzes industrial buildings that can be called generic or not specialized. To narrow the field of refurbishment, three major factors are defined. The first is to minimize the bill of the energy consumption of the buildings. This could be done either insulating the envelope, reducing the waste-volume to be conditioned climatically or creating facilities for energy production. The second is that the refurbishment or expansion of industrial buildings should try not to interfere on the production process that takes place in the building. In other words, the assembly of the elements in the construction site should be quick and easy, causing the least of disturbance at the workplace. Finally, the research makes an approach towards a robot integrated industrial or productive building .

Aug 1, 2013

By Mary Nelima Ondiaka, Kayode Henry Talabi, Oladunni Oyelola Alabi, Fatai Olufemi Aramide, Francis Gitau

Iron ore is essential in steel making; however, high-grade ores have diminished, making low-grade ores inevitable. These lowgrade iron ores need further beneficiation to upgrade the iron content. Currently, traditional physical and chemical methods are utilized and are not environmentally friendly. Bio-beneficiation techniques have emerged as a sustainable alternative for mineral recovery. This review delves into recent bio-beneficiation advancements for enhanced low-grade iron ore recovery using microbes. Research has revealed that bio-beneficiation methods such as bio-leaching, bio-flotation, and bio-flocculation have proven successful in iron recovery from ores. The bio-beneficiation process occurs in mild conditions using bio-reagents derived from microbes and offers a reduction of chemicals used in processing. Bio-beneficiation of iron ore potentially offers a relatively energy-efficient, cost-effective, and environmentally friendly method of maximum iron ore recovery. However, this review has identified a scaling-up difficulty in which a future approach for industrial-use applications is offered following a thorough sustainability assessment. Bio-beneficiation, using microbial processes, provides a viable avenue for maximizing iron ore recovery while tackling the constraints of dwindling high-grade iron ore resources and environmental sustainability.

Mar 16, 2024

By T. R. A. Davey

The technologies of lead, zinc and tin extraction have made varying degrees of progress over the past twenty years. Producers of all metals have faced increasing demands for reduction of pollution and environmental degradation, and the level of public concern is rising rather than abating. New processing techniques must therefore be not only economically feasible, but politically acceptable, even when the demands of "conservationists" and ?environmentalists? are unreasonable. A new generation of processing techniques has come into being, which do not rely on an expensive sintering stage, nor use metallurgical coke, which is difficult to make without serious pollution. They utilise intense reactors, conveying materials from one stage to the next preferably within an enclosed space, obviating fume emissions, and avoiding heat losses as far as possible. The acceptability of the new techniques? is increased if lowgrade or complex materials can be treated, along with a variety of returns and wastes. In addition, a good selling and servicing organisation seems to be as important as good process technology in determining the spread of the new processes. In the field of pyrometallurgical refining the need is for more general application of several recently developed techniques rather than a search for alternatives to the existing process technologies. However, there is a need for fundamental work investigating the phenomenon of oxygen anode overvoltage in the electrolytic zinc process, in order to make progress in the further reduction of energy consumption. There is also scope for further development and application of vacuum distillation to up-grade thermally produced zinc. This paper presents a personal view of processes which should be developed to overcome existing problems, as we approach the turn of the century,

Jan 1, 1990