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By X Yu, Y Shen

The iron ore products should be assessed in terms of in-furnace behaviour and overall furnace performance, their operation should also be optimised under industry-scale blast furnace (BF) conditions, in order to be sustainable and competitive, especially in the context of decarbonisation efforts in ironmaking. While lab and pilot-scale experiments can provide useful kinetics, they are expensive and risky and cannot replicate industry-scale blast furnace conditions for proper assessment and optimisation. In this paper, we review our recent progress at Shen Lab of UNSW in using state-of-the-art Computational Fluid Dynamics (CFD) models to assess iron ore products and examine the effects of their operations on BF behaviour in basic terms, including in-furnace phenomena (flow field, temperature field, species distribution fields etc) and overall BF performance (coke rate, reduction efficiency and top gas temperature etc). We have developed state-of-the-edge CFD models for different purposes, ranging from the static-state BF model featuring unique layered burden structures for offline assessment and optimisation knowledge building-up for iron ore products, to the transient-state BF model for online assessment and optimisation of iron ore productions by describing the transient behaviours of iron ore productions under industry-scale conditions. First, we have studied several iron ore products including the iron ore products used in the present BFs and emerging iron ore products like carbon composite briquette and iron-coke. Second, several iron ore operations are studied including optimisation of conventional burden operations like oxygen enrichment, batch weight tuning and new operations like coke central charging and hydrogen injection in BFs. Third, some time-sensitive operations are also investigated including the use of wet burden materials and the drop in blast temperature on BF performance. These CFD models offer cost-effective research tools for understanding the effect of iron ore products on BF performance and serve as a reliable marketing tool for existing and emerging iron ore products under a wide range of BF conditions.

Sep 18, 2023

By B. Csoke

The Bond and the Hardgrove methods are widely used for the determination of the material?s grindability. Generally, the determination of the Bond work index of inhomogeneous materials can be carried out with high deviation using the conventional apparatuses and methods, because of the highly different grindability of components. This is more significant when the composite cement?s grindability is measured, which highly affects the design and operation of cement grinding mills. A possible solution can be the combined application of the Bond-method with the determination of the component?s weight ratio in the product and perform the Bond measurement until the steady state conditions of grindability coefficient (G) and chemical composition of the components are reached. To prove the applicability of the above mentioned idea systematic Bond and Hardgrove grindability tests were carried out of two phase composite materials. The experimental results showed that the application of the combined procedure is proven in order to have a more accurate and reliable calculation of the Bond work index of composite materials, especially when the components have significant difference in the grindability and concentration. The measurements also showed the possibilities and limits of the grindability test methods.

Sep 1, 2012

By A. Arik

Reliable ore reserve estimates for deposits with highly skewed grade disributions are difficult tasks to perform. Although some recent geostatistical techniques are available to handle problems with these estimations, ordinary kriging or conventional interpolation methods are still widely used to estimate the ore reserves for such deposits. The estimation results can be very sensitive to the search parameters used during the interpolation of grades with these methods. This paper compares the ore reserve estimates from ordinary kriging using several cases in which certain search parameters are varied. The comparisons are extended to different mineralizations to show the changing effects of these parameters.

Jan 1, 1990

By Eric Hansen, Todd Wanless, Chris Mueller, Shannon Dunne, Scott Elmer

Between 2010 and 2018, Houston added more than 1 Million residents; the third largest rate of growth in the nation. With growth, the region faces new challenges with water supply, capacity of its wastewater system, and regional drainage. While tunnel construction has been limited in Houston since the Clean Water Program of 1990s, it is about to see a resurgence to improve water supply reliability and to reduce flood risks and sanitary sewer overflows. This paper examines the challenges with “going deep” below the built urban environment and related to high ground water; stiff, fissured clays; flowing silts and sands; faults; hazardous materials; and abandoned well fields.

Jun 13, 2021

By J. Finch, F. Rosenblum, McGill University

The self-heating of sulphides can be a major hazard in mining operations and concentrate handling, particularly during transportation and associated storage. Self-heating results from the oxidation of sulphide minerals and can vary from being insignificant to potentially hazardous to life and infrastructure. It is essential that there be a reliable test methodology that can categorize a given sulphide material as to its self-heating potential. By their nature, sulphide ores and concentrates are complex and variable mineral combinations making it difficult to predict their self-heating behavior a-priori based on mineralogy or with a simple "snapshot" test. Furthermore, self-heating behavior will depend on the state of oxidation of the sulphides as well as time, temperature and humidity. A review of available testing apparatuses and protocols that can be used to assess self-heating potential is presented. Each of these methodologies was examined in relation to its ability to predict the latent self-heating hazard of a sulphide material. Several of the methods were compared to illustrate their strengths and weakness. The results indicated that a number of the test protocols may produce false negative indications of self-heating potential, constituting an obvious concern to the industry.

Jan 1, 2014

By Hans D. Gougar

To meet an increasing demand for minerals, mining operations are moving to ever more remote regions. The lack of a local energy supply and infrastructure, coupled with social and regulatory demands for lowered environmental impact of mining operations, presents an opportunity for a seemingly unlikely competitor ? a nuclear power plant. The Modular Pebble Bed Reactor concept, currently in various stages of research and development around the world, offers a high degree of reliability and safety with minimal consequences for the local or global environment. The passive safety features of this design eliminate the need for the extensive active safety systems that add significantly to the cost of current water-cooled reactors. With the MPBR, as with all nuclear plants, there are no appreciable quantities of waste products released to the environment during normal operations. In contrast with conventional reactor designs, the MPBR would also remain radiologically safe even under the most severe abnormal circumstances. The key to the design is the fuel element. Enriched uranium microspheres are coated with various layers of pyrolytic carbons and silicon carbide to form a highly-temperature resistant particle that effectively retains all fission products. These particles are mixed with graphite and formed into 6 cm pebbles. A randomly packed vessel of such pebbles forms the reactor core through which helium is circulated as a coolant. Computer models and tests performed on actual pebble bed reactors confirm that fuel failure temperatures are not reached even during the most severe conceivable loss of coolant accident. The reactor drives a gas turbine cycle with resulting efficiencies as high as 48%, comparable to natural gas-fired units. The low price of uranium fuel and low maintenance requirements translates into competitive operating costs. However, high capital costs prevent the MPBR from competing with natural gas in most markets. In remote applications where no fossil supplies are readily available, the playing field is more level. This paper summarizes the features of two of the more promising candidates for remote applications and discusses the strengths of the MPBR from the perspectives of fuel supply and environmental impact.

May 1, 2002

By G. A. Irons, D. Guo

"The average spout height and width produced by bottom gas injection in a water model of a steel ladle were measured with an image processing technique. It was revealed that the spout height could be described by a Gaussian curve. A combined SIMPLE -VOF model was developed to simulate the liquid surface and flow. The results showed that, though the model produced reasonable velocity distributions and free surface positions, the spout height due to the dynamic head of the rising liquid was substantially lower than observed, indicating that the bubble dynamics at the bath surface play an important role in spout height.IntroductionDue to the enormous importance of gas injection and stirring in metallurgical processes, there have been numerous publications on water and numerical modeling of such vessels. The free surface of the bath has received considerably less attention, despite its importance. At the free surface there are often important chemical phenomena occurring that require a good understanding of the fluid flow; these would include reoxidation of steel, metal splash and fume formation. Furthermore, to understand the details of slag-metal interactions such as slag entrainment, metal losses to slag and the transport phenomena associated with refining reactions, it is necessary to understand the plume and spout interactions first.There have been few experimental studies of the free surface of liquid in gas-injected ladles [1- 3], and even fewer on numerical modeling. Brimacombe and co-workers [1] studied the gas void fraction in the spout region, using a double-tip electrical resistance probe. This sensor cannot distinguish between gas in bubbles about to break and gas in the freeboard. Thus, it is a matter of judgement as to the position of the free surface. Schwerdtfeger and co-workers [2] used a single probe configuration with a wire and a counter electrode in the liquid, so that the height of the continuous liquid phase was unambiguously determined. Irons and co-workers [3] measured the spout height by ultrasonic and electrical capacitance techniques. These techniques were as reliable as the resistance techniques, but were restricted to low flow rates."

Jan 1, 2001

By James C. Foley, David K. Rehbein

"In-situ characterizations of green state part density and sintering state have long been desired in the powder metal community. Recent ·advances in non-contact electromagnetic acoustic transducer (EMAT) technology have enabled in-situ evaluations of the acoustic attenuation and velocity as sintering proceeds. Pure aluminum (99.999%) and aluminum alloy powders were prepared with high-pressure gas atomization (HPGA). The powders were pressed in a uniaxial die and examined with acoustic waves for changes in velocity and attenuation during sintering. The changes in acoustic properties were correlated with sample microstructures and mechanical properties. Evolution of the acoustic echo train during sintering is shown to provide information on the state of sintering as well as having the potential for detection of interior flaws.IntroductionThe versatility of powder metalallurgy (PIM) technology in the manufacture of complex shapes has enabled an increasing amount of wrought and casting production capacity to be converted to PIM technology. However, ultrasonic inspection of green components produced using PIM techniques remains a challenge and is not generally practiced [1]. Inspection of PIM components in the green state is highly desirable, because the green part can be reclaimed with only accepted components being subjected to further costly processing. Another potential benefit is characterization and greater understanding of the sintering process itself. An increased scientific understanding of the sintering process enables intelligent process control, greater reliability of the production process and a lower rate of rejection of the finished product. In order to realize these potential benefits, it is necessary therefore that accept/reject criterion be based on real time nondestructive evaluation of the green-state components and the sintering process.Most current nondestructive inspection techniques suffer from their inability to perform inspections below the near-surface region with the exception of X-ray and to some extent pulsed eddy current [2]. X-ray inspection requires extensive shielding of production personnel and expensive film and film processing. While development of pulsed eddy current techniques have lessened the impact of the well-known skin effect, the depth of penetration of the induced eddy currents remains somewhat of an issue [2]."

Jan 1, 2000

By Amri Priambodo, Ian Leslie, Valérie Laflèche, Agustina Ratnaningrum, Robin Paine, Andrianus Sinaga, Willem de Beer

Freeport Indonesia consists of surface, civil and underground mining areas exposed to numerous geotechnical risks and hazards. PTFI uses various monitoring systems (Micro-Seismic, Firefly Light System, Mira Geoscience machine learning, etc.) to effectively manage these risks. The significant volumes of data from these sensors must be integrated into actionable information to provide the expected risk management. This occurs at the GeoEngineering Integrated Monitoring Centre (GIMC), a centralized department within the GeoEngineering Division, tasked with the responsibility to manage all geotechnical monitoring systems. The main hazard the GIMC is responsible for managing in real time is mine seismicity within the underground mining areas and the potential impacts on safe operations. Seismic system engineers achieve this objective through 24 hours a day and seven days a week operations of the GIMC, providing a centralized point of communication, alerts, evacuations and control during seismic events and emergencies. This paper will describe how the GIMC achieves its goal using reliable procedures and strategies based on detailed Triggered Action Response Plan (TARP), concise communications, novel technologies (FireFly Lighting System), and proven seismic re-entry programs to manage risk within the underground mining operations. The integration of geotechnical monitoring and reporting into a centralized group has improved the effectiveness and management of seismic risks and hazards at PT Freeport Indonesia (PTFI) mining operations.

Apr 26, 2022

By N Power, A D. Costar

There has been significant growth in mining and energy exploration in South Australia, which has identified new major potential opportunities. This sector generates significant economic value to the state and their support remains a priority for the state government. The delivery of this economic and associated community value to the state is dependent on the mining and energy sector being able to access reliable water supplies.The vast majority of priority areas for the mining and energy sectors are located in areas that have traditionally been of low priority from a water-use perspective and hence, data and knowledge levels are generally low.Recent studies have identified a potential increase in demand for water in the mining and energy sector for potential developments from approximately 40 GL to over 170 GL over the next ten years. The studies found that water and water infrastructure is the second highest proportion of planned infrastructure capital investment by resource companies. The South Australian GovernmentÆs Plan for Accelerating Exploration (PACE) initiative (PACE 2020), also identifies addressing the issues of location, use and management of South AustraliaÆs water resources as a key priority for the growth of the mining and energy sector.The Department of Environment, Water and Natural Resources (DEWNR) has developed the facilitating long-term outback water solution (FLOWS) initiative. DEWNR is currently undertaking a suite of programs to provide groundwater information at the regional scale to better target water supply options for mining and energy developments and community water supplies.The Goyder Institute for Water Research has leveraged significant research investment of $3 M to develop methodologies to interpret airborne geophysics to map groundwater sources.The FLOWS Initiative will provide key content for the PACE Water Program and will also assist in the development of water supplies for remote far north communities by identifying alternate groundwater sources to improve water supply security.This paper will discuss how developing an appropriate science and knowledge base will encourage and secure development where appropriate, enable prudent decision-making and policies regarding water allocation, accounting and licensing, whilst ensuring the protection of environmental assets.CITATION:Power, N and Costar, A D, 2013. Finding long-term outback water solutions, in Proceedings Water in Mining 2013 , pp 191-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By Ramanathan Ayothiraman, Anurag Singh

"An experimental program was undertaken to investigate the effects of randomly distributed basalt fibre on the index and engineering properties of Dhanori clay and to compare its performance with the properties of soil reinforced with polypropylene fibre. In the present investigation, 7 groups of soil samples were prepared at four different percentages of basalt fibre and polypropylene fibre content and tests were done for measuring their consistency limits, compaction characteristics, unconfined compression strength and consolidation properties. The test results indicate that the inclusion of basalt fibre in Dhanori clay resulted in significant improvement in properties. The improved properties are not comparable with polypropylene fibres, nevertheless, the improvement by basalt fibres is able to meet the typical design target values and the cost is very much less than synthetic fibres. More importantly, basalt fibres are environment friendly.INTRODUCTIONConstruction of buildings in low lands with engineered filling, flexible and rigid pavements for highways/airfields, and embankments for highways/railways are also part of major infrastructural development in addition to construction of tall buildings, bridges/fly overs, major dams and underground structures. The later projects require different improvement techniques than that is adopted in the former projects. Ground improvement techniques such as use of reinforcement inclusions within soil found as an effective and reliable technique. Especially such modification by fibre reinforcement, is primarily possible in engineered filling, pavements subgrade and embankments, where surface mixing is easier; and may not be feasible when stabilization/modification is required for deeper depths. In comparison with conventional reinforcement using geosynthetics (strips, geotextile, geogrid, etc.), there are some advantages in using randomly distributed fibre as reinforcement. In past few decades, the discrete fibres are simply added and mixed randomly with soil, in much the same way as cement, lime, or other additives.There are several studies (Ziegler et al. 1998; Puppala et al. 2000; Bei-xing et al. 2004; Cai et al. 2006; Tang et al. 2007, 2012, 2016; Abdi et al. 2008; Viswanadham et al. 2009; Le et al. 2015) that investigated the behaviour of polypropylene fibre-reinforced soil and reported that an increase in fibre content caused an increase in strength and shrinkage potential but brought on the reduction of swelling potential. The length of fibres had an insignificant effect on soil characteristics, whereas fibre contents proved more influential and effective. A study on rubber fibre conducted by Hambirao and Rakaraddi (2014) mentions that tensile cracking of clays can be improved with the inclusion of short rubber fibres, optimum fibre content was about 15 % of weight of soil. Several experimental studies (Babu et al. 2008; Chaple and Dhatrak 2013; Vibhakar and Nahta 2014; Soundara and Senthilkumar 2015; Goyal et al. 2015; Jayasree et al. 2014, 2015) were conducted on coir fibre-reinforced soil and concluded that it helped in reducing the swell potential and 1% fibre by weight of the soil almost doubled the CBR value. Martins et al. (2015) found that 4% of sisal fibre by weight of the soil reduced the visibility of cracks. Pillai and Ayothiraman (2012), Ayothiraman et al. (2014) and Sahu et al. (2016) have demonstrated that human hair fibres can be used to improve the properties of both fine grained and coarse grained soils."

Jan 1, 1900

By Gloria Lara

El presente texto señala la aplicación de la metodología de daño proporcionales a tres casos de correas transportadoras críticas que funcionan sobrecargadas en una minera al norte de Chile y así determinar el nivel de carga necesario para mantener un nivel de confiabilidad.

Mar 1, 2015

By J. A. Jankowski

The situation in the raw material market has brought into consideration the commercial exploitation of the mineral deposits on the deep sea bed and in particular the manganese nodules. They occur generally in depths of 4000-5000 m, partially covered or buried in bottom sediments. The deposits and their potential recovery have been intensively explored and researched during the past twenty years (Bischoff 1979, Halbach 1988, Padan 1990). Although the present market situation limits the rentability of deep sea mining on an industrial scale, the mining technology is being further developed in many countries. The stagnation phase in the deep mining issue allows sufficient time for conducting research on the precautionary protection of the deep sea environment and for consultation in the development of technologies with the least possible impact on it. The subject has gained in importance since autumn 1994, when the United Nations International Law of the Sea was signed. This also regulates human activities in international waters from the environmental point of view. As fields tests have shown in the past, even with the most modern technologies, mining of the manganese nodules will inevitably be accompanied by a resuspension of some bottom sediments. The generated sediment plumes will be further transported with the ocean currents and in the worst case form stable turbidity layers in different depths (Ozturgut 1981a, Baturin 1991). One of the problems of the environmental impact assessment is the estimation of the plume persistence before it eventually dilutes to approximately the ambient concentration level or settles at the bottom (Lavelle 1981a, Lavelle 1981b, Lavelle 1982, Thiel 1991a, Thiel 1991b). The aim of the research is to develop a numerical sediment transport model in connection with potential manganese nodule mining in a reference area located in the southeastern equatorial Pacific Ocean off Peru (Peru Basin, Discol Experimental Area). In this region, a German mining claim is registered and interdisciplinary field works of the TUSCH (German: TiefseeUmweltSCHutz, deep sea environmental protection) research group are carried out in order to obtain the required scientific background for evaluating of the deep sea mining impacts and to provide the necessary supporting data for the modelling (Thiel 1991a, Thiel 1991h).

Jan 1, 1995

By T. Richard Davies

This paper primarily deals with the application of wearfacing materials and their role within a well-established preventive maintenance welding program. Some examples are shown, as well as a synopsis of possible benefits and a compendium of methods and materials.

Jan 1, 1979

By John. A. Lombardi

Membrane technology for mining applications has gone beyond producing high-quality water from well- and sea-water by pushing forward with process water treatments to recover and concentrate metals, reagents and clean, discharge-quality waters. Therefore, the main objective of this work is is presenting state-of-the-art process alternatives using membrane technology to face four treatment issues common in the copper, gold and in general all the mining industry regarding process waters and streams that offer treatment challenges to the metallurgical and process engineers.

Sep 14, 2009

By Paulinelli Santos Rocha

A frota de equipamentos retro escavadeiras 345 CAT é responsável pela infraestrutura das minas do complexo Mariana, e este Projeto foi desenvolvido devido a baixa confiabilidade que estes equipamentos estavam apresentando. Foi desenvolvido um Projeto de seis sigma para aumentar a confiabilidade do equipamento que é medido pelo indicador MTBF, calculado pela fórmula: horas trabalhadas/ocorrências corretivas. O trabalho foi desenvolvido através de ferramentas de análise e solução de problemas no período de outubro/2012 a agosto/2013. O MTBF médio da frota era 29,39 horas sendo o benchmark de 47 horas. Foi utilizado o método da lacuna para estabelecimento da meta. Após definido a meta foi utilizada ferramentas de priorização dos focos mais relevantes. Para os focos encontrados foram utilizados análise de variabilidade e cartas de proporção, sendo cada causa classificada e priorizada, definido as ações e implantadas. Foi acompanhado o indicador de MTBF e implantados controles de rotina e padronização com o intuito de alcançar o resultado. Por fim, a meta estabelecida foi alcançada, chegando ao MTBF médio da frota de 42,50 horas.

Aug 8, 2018

By Marco Sonnenschein

Belt conveyors for tunnelling are industry standard and key to high performance of TBM drives. Conveyors reduce traffic in the tunnel and increase safety in the tunnelling process. This paper will illustrate the state of the art of tunnel belt applications in very long and curvy tunnels like the Coxwell Bypass Tunnel Project in Toronto, Canada.

Jun 23, 2024

By Karin Bäppler

Hydropower produces almost two-thirds of the world’s renewable electricity generation and delivers a major contribution on the ambition of the Paris Agreement and Sustainable Development Goals (SDG) with a range of benefits to society and environment. These include clean and flexible generation and storage in addition to reduced dependence on fossil fuels and avoidance of pollutants. The Limberg III PSP is one of the European projects that addresses the implementation of the UN SDGs. The challenge of the project is the construction of a 770 m long pressure shaft to be excavated with a TBM at an inclination of 42°.

Jun 13, 2023

By Karl Berger, Michael Steinkogler

The evolution in Metal Cutting: Inventors around the world have been successfully developing innovations for decades, but only some of these developments have had „GAME CHANGING“ potential. One of these innovations is the new developed saw blade LINCUT®, a patented changing system that paves the way for a fundamental reorientation of the entire saw blade industry worldwide through a simple and economical concept for rolling mills or heavy forging lines. Cost efficiency starts with the raw material: Circular saws equipped with a standard saw blade are expected to have a necessary 2 percent standstill per year due to required tool changing. The applied technology reduces this unnecessary loss of production by more than 50%. The ROI can therefore be reached faster which immediately lowers your production costs. No matter what material, conventional carbon steel or highly alloyed stainless steel, the coating and shape of carbide plates is perfected for extended tool life up to 25% with increased performance. Due to LINSINGERs own tool-technology-centre in Austria specialized in research and development of tools, constantly expanding R&D activities, best results are achieved in quality and cost efficiency: a (r)evolution in metal cutting.

Oct 1, 2019

By Jan Reimann

Increasing individualization with smaller quantities, growing competition from low-wage countries, and the continuous drive towards digitalization are the challenges that industrial companies in high-wage countries must face. The example of the Flender One gearbox modular system demonstrates how consistent standardization and digitalization are the enablers for AI, and thus already enable new business models and business approaches today.

Feb 22, 2026