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By Emre Turk, Suat Gullu, Candan Gokceoglu, Ahmet Sirri, Asli Can

In this study, the ground improvement application applied under the live railway bridge's approach embankments in Sivas, Türkiye was investigated as a case study. The soil profile is mainly composed of orangish conglomerate, clay, silty sandy clay, and under claystone, and mudstone units in the study area. As a soil improvement method, the Deep Soil Mixing (DSM) technique based on the principle of simultaneous mixing the ground while injecting with the water-cement mix, was selected. The application of DSM columns is designed to be 45 degrees horizontal, in order to reach the deepest point of the soft clay units for better improvement against settlement. The core samples were taken from the DSM columns and the compressive strength tests were performed in the laboratory. The results were higher than the minimum designed values. It means that inclined DSM columns were applied successfully, and the excessive settlement problem was solved.

Oct 1, 2022

By Scott G. Giltner, Alex Schwenk

An iron operation sought to extend the life of the mine by conducting a major pit pushback in an area close to several public structures and the neighboring town. The result of the pushback would make millions of tonnes of ore available for mining allowing many additional years of taconite mining. This paper discusses the initial development blasts conducted for the pit pushback. For the development blasts, it was determined that no fly rock should leave the mine site and that the blast vibrations should be as low as possible, but specifically under 19 mm/s (0.75 in/s) at a nearby sewage treatment plant. One issue complicating the blast design was the variation in hole depth within any given blast. For the initial sinking shot, the hole depths varied from 6.4 m (21 ft) to 12.5 m (41 ft). In the subsequent blasts the hole depths within each blast could vary up to 5.8 m (19 ft). Various tools were employed to design the blasts to ensure there was no fly rock and that the blast vibrations were as low as possible. UAV surveys of the blast areas were conducted to provide a 3-D representation of the free faces and bench surface. The 3-D point cloud produced from this was used to measure the shape of the free faces. Once the shape of the free faces was quantified, it was possible to establish proper placement of the crest holes and develop a custom explosive load for each blast hole. In addition, signature hole analysis was performed for each blast to determine the optimum delay time that balanced the need for minimal vibration, prevent fly rock, and a well fragmented muck pile. Electronic detonators were applied to achieve the necessary control of the blast that balances these three concerns. The results of the seven blasts conducted to date provided the desired results. The peak vibration level at the sewage treatment plant for the seven blasts was 10 mm/s (0.40 in/s). The only fly rock occurred when there was a miscommunication in the blast design resulting in under burdened holes on the front row. To date, the mine has been able to safely expand the pit into an area that will add many years to the mine life. The muck piles have been well fragmented with reports from the shovel that they have all dug well.

Jan 21, 2025

By M Rea, E O’Connell

Decarbonising explosives manufacturing and catalysing low-carbon mining supply is a significant global challenge. Low-carbon manufacturing precincts – clusters of geographically close businesses across multiple industries that share a goal of adopting firmed renewable energy and decarbonising process emissions – offer one potential solution. In an Australian first, Orica commissioned tertiary catalyst abatement technology in 2023 to mitigate greenhouse gas (GHG) emissions at its Kooragang Island (KI) facility in New South Wales (NSW), Australia. The EnviNOx® technology (ThyssenKrupp Industrial Solutions AG, Dortmund, Germany) used reduces nitrous oxide (N2O), a potent greenhouse gas arising as a by-product of nitric acid manufacture. As a result, mining customers in NSW are now benefitting from ammonium nitrate (AN) products that are almost 50 per cent less emissions-intensive than those Orica previously offered. The $37 million project is a private-public partnership that has involved partners across Federal and State government, global engineering and technology vendors, local community groups and local carbon advisors to overcome financial barriers.

Sep 1, 2024

By D Brown, K Markovic, Z Tabor

From ancient times to the modern world, the mining industry has played a pivotal role in shaping the society that we live in today. It remains an integral part of everyday life and is a catalyst for both technological and economic growth. With finite resources on Earth, and growing pressures surrounding climate change and the environment, space mining opportunities have become of increasing interest. Recent discoveries have shown celestial bodies including the Moon and surrounding asteroids, contain an abundance of critical minerals, as well as resources necessary to sustain human life. These discoveries coupled with a transition into the digital and autonomous age, offer an innovative solution to solving some of the mining challenges currently being faced on Earth. Similarly, they also offer a pathway to enabling deep space exploration and off Earth exploratory missions. However, like with mining operations on Earth, space remains and immensely challenging and complex operational environment. The inhospitable nature of space poses new challenges, including communication barriers, lunar dust, cosmic radiation, and gravity. The challenges and risks are not just technological, as Environmental, Social, and Governance (ESG) factors must also be considered to prevent unintended consequences and hazards. Furthermore, future workforce, law, financial, and security systems must evolve to enable space mining to take place. These are all known aspects to begin with, but as the complexity of the space grows it becomes apparent that a holistic approach to assess and manage these factors will be required.

Sep 1, 2024

By A K. B Chigwada

Mining organisations grapple with the same problems year after year, wasting incredible amounts of time and money. According to estimates from the International Labour Organization (ILO), over one million work-related deaths occur annually, and hundreds of millions of workers suffer from workplace accidents and occupational exposure to hazardous substances worldwide. Many accident reports cite human failure as a primary cause (Busse and Johnson, 1998). The workers at the Bhopal chemical plant pumped methyl isocyanate into a leaking tank (Morehouse and Subramaniam, 1986). On 3 December 1984, more than 40 tons of methyl isocyanate gas leaked from a pesticide plant in Bhopal, India, immediately killing at least 3800 people and causing significant morbidity and premature death for many thousands more. The company involved in what became the worst industrial accident in history immediately tried to dissociate itself from legal responsibility (Broughton, 2005). Australia is not spared from safety problems either (Lucas, 2022). The ILO Convention 176 (1995) as a response provides that national law should inter alia provide for the supervision of safety and health in mines; the inspection of mines by designated inspectors of the competent authority; the procedures for reporting and investigating of fatal and serious accidents; the compilation and publication of statistics on accidents, occupational diseases and dangerous occurrences; the competent authority to suspend or restrict mining activities on safety and health grounds until conditions giving rise to the suspension are addressed; and worker consultation on matters related to safety and health in mines. This has assisted in getting enough data to define the magnitude of the problem to the mining sector.

Apr 16, 2024

By C Tapia, B Hay

There is a close relationship between the mining industry, economic growth, and technological and social development. Mining activities benefit all economic agents, but only during a timespan determined by available reserves, primarily driven by internal factors such as production rate, technology and costs, and external factors such as prices determined by the market and taxes and royalties controlled by governments (Gordon and Tilton, 2008; Henckens, 2021; Tapia Cortez et al, 2018). The intense use of Mineral Commodities (MC) needed to maintain the current lifestyle has placed ore depletion as one of the main threats to sustainable economic, social and technological development. However, ore depletion does not only arise due to the finite nature of MC, price fluctuations or technological challenges. It is also triggered by the ‘economic limits of extraction’, determined by the optimisation of financial factors and technical restrictions within the regulatory framework (Henckens, 2021). Most reporting standards – if not all – define ore reserves as ‘the economically mineable part of a Measured and/or Indicated Mineral Resources’ determined by the technical and economic viability of extracting, processing and commercialising MC having the NPV as the fundamental decision – making tool (JORC, 2012; Krzemień et al, 2016). However, is the NVP an ‘economically’ basis index able to capture the complexity of economic phenomena? No, it is not, and it is crucial to define what is economic and financial. Although related, they are different disciplines. Economics studies the behaviour of the different market agents, including human behaviour and policies and explains the factors involved in the scarcity (or surplus) of goods and services. Finance focuses on financial systems and managing funds considering the time, cash available, and risk. It involves banks, loans, investments, and savings and can be considered a small subset of economics (Simon, 1959; Tapia Cortez et al, 2018). Given the economic nature of ore Reserves, endorsed by governments (Figure 1), NPV is an incomplete tool to determine ore Reserves as it limits the problem to simply maximising cash flows instead of optimising the economic benefits for all economic agents. In addition, using the rigid scheme of controlling taxation – unable to adapt to new market or economic conditions and systematically increasing – within the NPV framework only increases the sub-optimisation of ore reserves, mainly due to the systematic taxation rise. Short-term benefits of higher taxes and royalties are unlikely to offset the impacts of reducing exploration and project development in the long-term, which not only boosts ore depletion concerns but also reduces competitiveness, threatening economic and social welfare (Fisher, Cootner and Baily, 1972; Gordon, Bertram and Graedel, 2007; Lilford, 2017; Mardones, Silva and Martínez, 1985; Radetzki, 2009; Rodrik, 1982; Tan, 1987; World Bank, 2000). Holistic methods and collaborative tools, able to dynamically simulate and assess how changes in the technical settings, regulatory framework (taxes and royalties), and financial factors affect the availability of ore reserves and the impact for all economic agents, should be incorporated into the evaluation process to fill the gap.

Aug 2, 2023

By Bradley Stoughton

AT THE meeting of the Board of Directors on May 20, the resignation of Bradley Stoughton as Secretary of the Institute was presented and regretfully accepted by the Board. The letter of resignation follows : Gentlemen: About two years ago, I indicated to the President and some members of the Board my belief that the office of Secretary of the Institute should not be a permanent one. It is my observation of events, not only in our own Institute, but also in several sister societies, that too long a tenure of office by the Secretary inevitably leads to a situation which is not good either for him or for the society. After submitting this in writing to the Directors on February 17, 1920, I was overpersuaded by members of the Board to defer resignation until a more convenient time for the

Jan 1, 1921

By Douglas Bunting

(Wilkes-Barre Meeting, June, 1911.) WITH the gradual exhaustion of the upper veins in the anthracite coal-fields, the problem of mining at greater depths acquires increasing importance and demands the consideration of a number of important factors, one of which is the greater earth-pressure and the consequent necessity of stronger support o for the roof. Under the pillar-and-chamber system, almost exclusively followed in the Northern anthracite-field, the highest economy in mining is generally secured by leaving, on first mining, pillars only sufficient to support safely the overlying strata. As to the necessary size of such pillars, the opinions of mining experts are widely divergent. In establishing the width of chambers and pillars, the thickness of vein and its depth below the surface have received little consideration. For. instance, it has been quite usual to work both overlying and underlying veins with the same width of chambers and pillars, when the lower vein was two and one-half times as thick, and twice as fits below the surface, as the upper. In view of the generally-accepted theory that the crushing-strength of coal-pillars of the same base-area becomes less with increased height, it is probable, in this instance at least, that the most economical mining has not been secured. This question of adequate pillar-support is economically less important down to about 800 ft. than at greater depths; and it is with reference to mining at these greater depths that the study of the subject here presented has been prompted. The necessity of leaving larger pillars, involving greater mining-costs per ton and also smaller yields per acre, is one of the troubles of deep working. To mine without leaving adequate pillar-supports will result, sooner or later, in a squeeze. Limited areas, it is true, have been mined at certain widths of

Sep 1, 1911

By W. C. McClain

In the design of underground excavations, rock mechanics considerations are nearly always based on an elastic behavior of rock. Most rocks do exhibit a certain amount of elasticity, and the application of principles and concepts of elasticity to rock mechanics problems has been largely responsible for progress in the field over the past 10 or 15 years. No doubt the theory of elasticity will remain the most useful analytical tool available for both the design of underground openings and the interpretation of phenomenological data.

Jan 1, 1967

By C Berglin

Is the Northern Territory different? Certainly it is more remote, has less people and relies more heavily on two or three industries for its survival. On the other hand, its mining industry is governed by Acts not dissimilar to those of the major States - a Mining Act provides the basis for acquisition of tenure, a Mine Management Act provides regulatory control, a Mineral Royally Act collects revenue in return for the right to utilise the land's bounties, an Environmental Assessment Act provides the public face to rehabilitation and environmental safety, and the Aboriginal Land Rights (NT) Act purports to give development criteria for inalienable land use. With the exception of the latter, at least until the advent of Mabo, all these are simply variations on a theme, and are common to most States. This paper will show how the Department of Mines and Energy works in relation to the Northern Territory mining industry.

Jan 1, 1994

By A J LYNCH

It was Harold McMillan, Prime Minister of England 30 years ago, who used the phrase "The Wind of Change" to describe political events in Africa in his day. So well did this phrase capture the spirit of the time that it echoed around the world, and the echo has never stopped. Change is the constant factor in the society in which we live and everyone of us has had experience of the effect which it has had on our professional and personal lives. Change will not stop, it will continue at an increasing rate and the questions we must answer are how do we prepare ourselves to meet the challenge of future change and how do we take advantage of the opportunities which it will bring? It is these questions which I wish to discuss in this address.

Jan 1, 1989

By V. Sheikhzadeh, M. R. Sheikhzadeh, A. Haratian, M. Zare

High Pressure Grinding Roll (HPGR) as an efficient grinding technology plays a major role in mineral processing plants. Investigating the effects of this technology on different parts of mineral processing circuits reveals this technology’s capability. In this paper, HPGR grinding effects on an iron ore beneficiation circuit, in comparison with conventional crushing systems were studied. A representative feed sample was taken from an iron ore beneficiation plant, then crushed to minus 6 mm in a laboratory by two methods: HPGR and cone crusher, and finally a concentrate plant circuit was simulated. Plant simulation was performed by doing laboratory tests consisting of grinding, magnetic separation, flotation and filtration on HPGR and cone crusher products, respectively. According to comminution tests results, in particle sizes smaller than 6 mm, a cone crusher product is coarser than an HPGR product. Also, the Bond ball mill work index of the HPGR product was 10% less than the crusher product. Therefore, based on the Bond formula in applying HPGR, ball mill power consumption decreased by 12%. After ball milling to minus 100 microns, magnetic separation tests results showed that the recovery of the cone crusher circuit output was 90.8% and the product Fe grade was 66.4%. For the HPGR circuit these figures were 87.6% and 67.3%, respectively. Therefore, by using an HPGR, a higher Fe grade of the final concentrate was achieved. A flotation test was then performed on the magnetic separation concentrate, where the results showed that the crusher circuit recovery and the sulfur grade of the product were 96.5% and 0.192%, respectively; whereas the HPGR circuit recovery was 97.2% with a sulfur content of 0.185%. Findings revealed that flotation performance in the HPGR circuit was more efficient than the crusher circuit. Vacuum filtration tests on concentrate produced through the HPGR circuit resulted in a moisture content of 12% that was 2% higher than the crusher circuit’s concentrate in the same condition. Keywords: High pressure grinding roll, power consumption, magnetic separation, flotation, filtration

Jan 1, 2020

By Dan Ifrim, Andre Solecki

Tunneling could be a major challenge to tunneling contractors as tunneling operations can be seriously affected by the Tunnel Boring Machine (TBM) performance. Specifying the appropriate TBM methodology, selection of systems and features, is critical for managing tunnel risks and contribute to successful tunneling project. The paper analyzes tunneling records from the recently completed City of Toronto’s Ashbridges Bay Treatment Outfall tunnel project and underlines the righteous selection of the TBM type and associated TBM systems in achieving good advance rates during tunnelling and managing project risks. The paper intends to draw attention of a few aspects of TBM technical specification importance and highlight the lessons learned from this process.

Jun 13, 2023

By B Stump

Reliable particle size analysis in minerals processing plants is a critical factor to the economic return of a plant. As recovery of valuable minerals is compromised for particles outside the optimal size range, effective and reliable particle size analysis is more crucial than ever, particularly in the current upswing of the global commodities market. Inefficient particle size analysis can lead to excessive over-grinding, thereby significantly increasing energy consumption and reagent costs, whilst negatively affecting process operation, thickening capacity, water recovery and tailings disposal.Australia’s first installation of a particle size analyser in Iron Ore has been monitored with great interest by the industry. Previously, manual size sampling at Rio Tinto’s Paraburdoo fines processing plant involved off-site sample analysis, with a turnaround measured in days. The Outotec PSI® 500 particle size indicator, commissioned in July 2009, takes approximately three minutes per line at site.The paper will include details on the following:• plant description,• sampling design,• PSI® 500 analyser functionality description, and• key learnings from site.

Jul 11, 2011

Commissioning is one of the many phases of a project, it has inter-dependencies with the other phases, as they have amongst themselves, and has its own terminology and distinctive features. Commissioning time and cost can severely affect project economics, especially through unrealistic estimating, and requires a separate management team to ensure full control is. maintained. Targets to be achieved in commissioning are identified, together with the necessary policies to achieve them. Factors which have to be taken into account in applying these policies are Discussed.

Jan 1, 1986

By Jan Krull

A high productive coke making process in connection with stringent emission control has clearly become a demand of plant operators and stakeholders. Further to this, availability, quality and coal costs are key concerns for the iron and steel industry in its efforts to optimize raw material cost. Today, the optimization of raw material cost in integrated steel works has further gained priority. Coking coal reflects up to 20% of the cost of steel. In top charged batteries coal preparation and blending is one of the concerns to lower coal cost by maximizing the percentage of non-coking coals in the blend. Stamp charging technology is technologically and economically an effective solution in the process of pre-carbonisation. Paul Wurth’s jumbo top charged oven as well as proven stamp charging technology have recently set new benchmarks in Europe, India and Brazil in terms of productivity, stability and emission control.

Aug 1, 2018

By H. Uygucgil, C. Kwang

The use of remote sensing and geographic information system techniques in mineral exploration is still underutilised. There is a need to explore the potential of new robust remote sensing and geographic information system techniques in the field of mineral exploration. In this study, we mapped the argillic alteration associated with epithermal gold-silver mineralisation. A band ratio of band5/band6 and Crósta technique on Advanced Spaceborne Thermal Emission and Reflection Radiometer within the Google Earth Engine Environment was applied. The bands 5 and 6 were selected for the band ratio after critically analysing and comparing the illite spectral extracted from the Advanced Spaceborne Thermal Emission and Reflection Radiometer image and the illite spectral obtained from the United States Geological Survey spectral library. The band ratio and Crósta technique identified and mapped the Ovacik goldmine and other argillic alteration zones. Even though both methods mapped out the argillic alteration zones associated with gold-silver mineralisation, the Crósta technique produced the optimal argillic alteration. The study demonstrates the analytical capabilities of Google Earth Engine in image processing and analysis for mineral exploration, such as discovering hydrothermal alteration associated with mineralisation.

Jul 23, 2025

By S. S. Klima, H. Jiang, T. W. Beck, Y. Zheng

Researchers at NIOSH’s Pittsburgh Mining Research Division (PMRD) performed comparative testing of six different water sprays at pressures ranging from 689 kPa (100 psi) to 6,895 kPa (1,000 psi) in a 14.5-m3 (512-ft3) confined dust chamber. Testing was conducted to determine the effect of various pressures on each spray’s respirable coal dust knockdown ability. It is known that higher water pressures are typically preferred for lowering airborne dust concentrations, but it was important to determine at what pressure range the dust knockdown ability of each spray plateaus or reaches its minimum dust concentration. Results from this testing showed that several sprays saw up to 100% decrease in dust concentrations during the five-minute water spray testing period, with some occurring well below the maximum 6,895 kPa (1,000 psi) spray pressure.

Feb 1, 2023

By R. E. Fanning

"IntroductionThe Aluminum industry is one of many materials industries which strive to make their material the preferred choice for large volume products. In some applications one material has a natural advantage over others, but more frequently several materials compete with one another, each providing one or more advantages and some trade-offs. Customers may design their product with several objectives such as minimum system cost, maximum customer appeal or maximum manufacturing flexibility, choosing materials which best combine cost and performance. In such markets it may become necessary for a material supplier to enhance the attractive features of the particular material to outweigh its disadvantages.It is difficult, if not impossible, to predict how various materials will evolve. Technological breakthrough, government regulations, material availability or sociological issues may redefine the balance between competing materials. In spite of some uncertainty regarding the competitive position of competing materials, there is little doubt that unrelenting pursuit of product quality improvement and cost reduction are essential to future viability of the aluminum industry. It is the intent of this paper to identify some areas where technological improvement would be beneficial. Thus this paper is a collection of briefly described problems that will hopefully stimulate the thoughts and research required for knowledge based solutions. Rolling ProcessA particular example is the beverage can industry where aluminum, steel, glass and plastics vie for a share of the m.arket. The high cost of aluminum relative to steel or glass requires minimizing the amount of metal per can. The high intrinsic value of aluminum has led to extensive recycling of cans although net metal cost is still higher than that of the competing materials. Intensive engineering of the beverage can led to improved design and better understanding of material requirements. These improvements permitted substantial reduction in sheet thickness over the past decade. The downward trend in metal thickness for beverage can sheet is shown in Figure 1."

Jan 1, 1988

By O Handayani, R Barr, E Isaaks

The mining industry has focused a great deal of attention recently on the impact of blast movement on grade control. Although the problem of blast movement and its contribution to dilution and ore loss is well known, solutions to the problem are less than satisfactory. Perhaps the most recent innovation is the application of blast movement monitoring (BMM) devices to quantify blast movement. These devices emit an electronic signal and are planted at surveyed locations within the preblast material. Following the blast, their new locations are found using an electronic scanner. The magnitude and direction of the blast movement is given by the vectors between the pre- and post-blast BMM locations. However, it’s not clear how the BMM vector data can be best used to minimise dilution and ore loss. One common solution is to displace preblast dig line polygons by distances indicated by the BMM vectors. However, studies of BMM vectors show that blast movement not only displaces material laterally but also mixes material internally within the bench (Thornton, 2009a).This paper presents a method for modelling the post-blast muck pile that accounts for displacement and internal dilution using simulated annealing. The preblast ore control block model is re-blocked to 1?×?1?×?1?m sub-blocks. Each sub-block is displaced by simulated BMM vectors conditional to post-blast surface topography and blast initiation sequence data in addition to BMM vector data. The displaced sub-blocks are aggregated into new ore control model blocks whose grades are calculated from the contained sub-blocks. New dig lines are then designed on the post-blast muck pile model using the new ore control block model grades. A case study based on actual data is provided.CITATION:Isaaks, E, Barr, R and Handayani, O, 2014. Modelling blast movement for grade control, in Proceedings Ninth International Mining Geology Conference 2014 , pp 433–440 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014