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By M Rafty, A Markham, S Atkinson, M Heyting

Over recent years there has been a significant increase in the number of miners in the Pilbara region of Western Australia targeting channel iron deposits (CID) located in valleys, intersected by ephemeral creeks and below the groundwater table. The falling iron ore price has triggered a drive to reduce cost and maximise yield. Creek diversions provide an opportunity to maximise the utilisation of orebodies and extend the life-of-mine.Creek diversions that are required during mining operations to access ore and provide flood protection have historically been constructed as uniform engineered channels designed primarily for flow conveyance while minimising earthworks costs; however, the design of diversions becomes more complex when they are required to function in a similar way to the existing creek system during operations and remain stable during more extreme events than would typically occur following mine closure, in accordance with current regulatory guidance. The design specifications for closure are often more rigorous than the operational phase, and could incur significant additional cost to implement retrospectively if not planned and designed upfront.The complexity of diversion design depends on site specific factors such as: the size of the creek to be diverted; hydrology; corridor restrictions; geomorphology; hydrogeology; geology; environmental and heritage values; potential impacts and the risk to operations and environment. The complex interactions of these factors must be well understood and hydraulic modelling undertaken to characterise the existing creek system, demonstrate the diversions, provide adequate flood protection during operations, and can function in a similar way to the existing system following mine closure. This paper presents key design considerations for Pilbara creek diversions, operational and closure requirements, mine planning considerations, risks, cost saving opportunities, and the benefits of an integrated approach to design.CITATION:S Atkinson, A Markham, M Rafty and M Heyting, 2017. ‘Back to the future’ – resilience in historical context and implications for the future, in Proceedings Iron Ore 2017, pp 367–374 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By IPMI Educational and Scientific Foundation

It is with great pleasure that we announce the availability of this fifth issue of the IPMI Journal, a publication of the International Precious Metals Educational and Scientific Foundation. This digital peer reviewed publication has been created as a vehicle for the sharing of technical information related to the science and technology of precious metals. Since 1976, the International Precious Metals Institute has championed the exchange of information of critical importance to the precious metals scientific and commercial communities through its various communications vehicles. This has included instructional videos, annual conference symposia, special topic committee meetings, regional seminars, and professional and student achievement awards. Due to the breadth of important topics related to all aspects of precious metals, it has been the vision of the IPMI to provide a publication available to the general public that would become a key source of pertinent topics containing high quality publications by experts in their fields of study. Historically, the IPMI has attracted world renowned experts in many fields (including Nobel Laureates Henry Taube, Ei-ishi Negishi, Robert Grubs, Professor Ben Feringa, and David MacMillan) in the dissemination of discoveries, inventions, and industry proven practices. Such information has a total value greater than the sum of its parts as seemingly unrelated innovations from distinct focus areas can be adapted to solve problems. Because of this important characteristic of information exchange, we have decided to create a digital journal, available to the general public, that will not only communicate state of the art discoveries and sound practices, but will also review historical communications from the IPMI’s archives that have value and use even in today’s environment.

Dec 1, 2024

By C. Treworgy, C. Chenoworth

Geologic and technical factors such as coal seam thickness, stripping ratios, roof conditions, partings, faults, and size and geometry of the reserve block greatly impact the availability of Illinois coal for mining. Residential and commercial developments also restrict access to coal reserves in some areas. Despite the collective effects of these factors, large blocks of bituminous coal reserves suitable for efficient, low-cost underground mining remain available in Illinois.

Feb 24, 1997

By Fengyu Ren, Ruslan Puscasu, Kunpeng Yu, Gideon Chitombo, Liangliang Kang

Weak rock mass and poor flow of material can cause excessive ore loss and dilution in sublevel caving. This paper proposes a method to establish design parameters for an inclined deposit within a weak rock mass and evaluates its effectiveness through a case study. In order to solve the problem of low production capacity and poor safety conditions of sublevel caving mining at the Yingfangzi silver mine in China and to ensure a smooth production from the refractory ore body, it is necessary to select appropriate stope structure parameters. Based on random medium theory of gravity flow and the improved equation of ore discharge in random medium, an end wall drawing experiment is carried out to determine the optimum design and flow parameters. It was observed from the experiment that, due to the influence of the randomness of particle movement, there is a mismatch in the flow parameter measurement. The flow characteristics and distribution of the marker particles are different from that of the tested particles resulting in large drawbody shape distortion. The study finds that the flow parameters obtained by the new method are more practical and account for drawpoint width and recommends that the new method for determining the sublevel stope height is used when the drawbody is a non-standard ellipsoid. The outcomes have shown a significant reduction in the dilution and improvement in the recovery rates, and the safety and efficiency of mining have been greatly improved.

By B. Samanta

LHD (load haul dumper) is now used as a loading machine for intermediate mechanization in underground coal mining. For survival in the intense competition in the global business environment in recent years it is essential that LHD machine should be reliable and maintained effectively and efficiently. This paper seeks to study the reliability, availability and maintainability (RAM)of an LHD machine with failure and repair data by Markov modelling. The constraints and reasons for machine unavailability are outlined. The reliability and maintainability of an LHD and its subsystems are evaluated. Possible modification or design alternatives are highlighted. Reliability and maintainability of an LHD system are disappointing. There is room to take decisions on optimal maintenance planning and machine improvement from this analysis. Keywords: reliability, availability, maintainability, Markov model, LHD

Jan 1, 2004

By Jason Palmer

"Water in mining is the commodity that has driven the mining industry for decades. Often used frivolously, modern economic and social pressures are forcing change to use less water and to improve the quality of water and effluents. Used in many processes, water is ultimately consumed in tailings disposal and technologies which can increase the recovery of water are constantly being developed. Filtration and thickening are often seen as competing technologies for water recovery however new cases are developing that show significant advantages can be achieved by combining the two technologies to develop the most effective solution. Supported by case studies this paper investigates the merits of each of the technologies and which strategies of combining the two produce the best outcomes.INTRODUCTIONMineral processing applications generally require water for the processing of ores, whether utilising physical or chemical methods. Water is first added in the milling stage and additional water added as required throughout the circuit. Water losses from the circuit are principally associated with the tailings stream. Optimised water recovery is necessary both because it is a scarce commodity and to minimise the environmental impact.Water recovery is usually accomplished through a sedimentation or filtration processes. Water can be removed from the tailings impoundment by evaporation but this does not improve the mine’s water consumption. The water recovery methodology also determines the water quality; increasing water recovery concentrates solutes in the process water and may create recirculating loads of fine solids."

Jan 1, 2016

By T. Prietl

Metallurgical vessel linings are multilayered, consisting of refractory bodies, insulation materials, joints, and additional space to control for thermal expansion. A unique biaxial hot testing press (BHTP) was installed at the RHI Refractories Technology Center Leoben, Austria to enable the three-dimensional behaviour of complex vessel lining segments to be investigated under simulated service conditions. Using the BHTP, the heat up and thermo-mechanical behaviour of magnesia chromite brick lining segments with and without mortar filled joints were examined. The results obtained during the initial heat up provided validation of CFD modelling of the lining system. In addition, after the heat up and under steady state conditions, the lining behaviour during deformation-controlled compression and relaxation was examined. These analyses generated important data regarding the stiffness, joint compressibility, and brick damage of the lining segments after cyclic loading and unloading as well as the benefits of using mortar joints in the lining. These investigations were performed in collaboration with the Christian Doppler Laboratory for Secondary Metallurgy of Nonferrous Metals, University of Leoben, Austria. The BHTP has been operational since November 2004 and is providing information regarding the thermo-mechanical behaviour of different lining segments.

Jan 1, 2007

By Larry A. Haas

The chemistry of current or potential SO2 removal processes can be placed into four categories: (1) reduction, (2) Liquefaction, (3) direct dissolution, and (4) oxidation. Methods that involve reducing SO2 to elemental sulfur appear promising since this product can be easily handled, shipped, and stock- piled. Unfortunately, SO2 cannot always be reduced directly when other oxidizing agents are present. Thermodynamic data indicate that some oxidizing reagents will also consume reductant at the reduction temperature. A two- stage process can be applied to waste gases that contain excessive quantities of oxygen, nitrogen oxides, and water vapor. The best sorbent for the first stage appears to be a nonalkali or nonalkaline earth medium since this medium more readily releases the SO2 for reduction in the second stage.

Jan 1, 1973

By C. M. Mason

The methods currently used by the Bureau of Mines to evaluate the sensitivity, strength, incendivity, gaseous products, and physical properties of explosives and hazardous chemicals are described. Included are the tests used to evaluate explosives which arc certified as permissible for use in underground coal mines.

Jan 1, 1972

not weaken. I saw him shortly before he was killed; his conduct under fire was splendid and an inspiration to his men. His loss is felt deeply by all ranks. Thanks to him and to others, who like him, paid the full measure of devotion to their country, our line was held until the critical situation in that vicinity was at an end. He died the true death of a soldier, with his face to the enemy. As we now look back, it is easy to believe that this holding of the line of defense intact by General Carey and his men was a determining factor in the outcome of the war. To have played so important and noble a part in this vital effort as that taken by Perry is assuredly the privilege of few. Our lives, it seems, are like capital entrusted to us to be expended as wisely and effectively as we may. With them we purchase whatever of accomplishment the stuff that is in us permits. It is impossible to escape profound regret that a career so full of the highest promise, and a personality so overflowing with all that is fine and lovable, should have been cut short at the age of thirty-one. Yet who can doubt that in a few months Perry bought with his life the fullest achievement of a life-time—a glorious part in the salvation of Liberty and Justice and Decency, indeed of Civilization itself! L. C. Graton.

Jan 1, 1920

By D. Xie

An in situ gravimetric technique based on wetting and capillary action principles has been used to investigate the wetting and penetration of synthesized alumina samples and commercial magnesia spinel refractories by CaO-SiO2-Al2O3-Fe2O3slags. Synthetic slags of 40CaO-40SiO2-20Al2O3 (in weight per cent) with 0 to 9 weight per cent Fe2O3were used and the experiments were conducted at temperatures 1370 to 1470ºC under argon. The contact time between the sample and the slag was 30 minutes. The results show that the wetting and penetration are enhanced by the iron oxide addition in the slags. Addition of Fe2O3from 0 to 9 weight per cent resulted in a significant increase in the slag penetration into the magnesia spinel refractory by a factor of about 7 and a moderate increase in the synthesized alumina by about 60 per cent. The addition of Fe2O3enhanced the wetting (??cos?, where ? is the surface tension of the slag and the contact angle between the slag and the refractory) by 5 to 18 per cent. An increase in temperature from 1370ºC to 1470ºC resulted in a significant increase in the penetration of a 6 weight per cent Fe2O3slag in the alumina and magnesia samples by a factor of4 to 5 and a decrease in wetting by approximately 30 per cent. Keywords: refractories, slag penetration, wetting.

Jan 1, 2004

By James Addis, Zoheir Khademian, Marcia L. Harris, Charlie Matthews, Y Zheng

Shale gas wells can sometimes drill through coal reserves. Hypothetically, the caving of the gob from longwall coal mines may deform the shale gas well casing and potentially result in a breach. NIOSH researchers studied the permeability of the surrounding ground strata that may affect the potential for an inflow of gas into an underground mine environment. An overview and comparison of measured permeability values under differing cover depths (147 m and 353 m to the Pittsburgh coal seam) and mining cycle phase will be presented and discussed in this report. The findings highlight data-driven experimental evidence that affect the interaction between gas wells extraction and mining operations that may lead to potentially hazardous environments.

Feb 1, 2025

By L. M. Lowe, D. B. Chambers, D. G. Feasby

"The presence of the naturally occurring radioactive elements uranium and thorium in rare earth (RE) resources can present challenges in achieving regulatory and social acceptance. The discovery and awareness of radioactivity in mineral resources radioactivity typically generates strong public intuitive responses that may be project prohibitive; a significant proportion of such resources contain radioactivity.The objectives of this paper are to demystify the presence of uranium and thorium in RE resources and to demonstrate how a RE project can be safely developed, operated and closed from a radiological perspective. Radioactivity in RE resources is principally thorium-based. Thorium is interesting and challenging from a metallurgical perspective – one of those stubborn metals commonly assessed as refractory. Thorium is difficult to mobilise into solution and easily precipitates out. Thorium is a common element in the earth’s crust – about 10 ppm on average, and natural geophysical systems conclusively demonstrate its immobility. Specific mine tailings contain elevated levels of thorium, but the contained thorium is neither a significant ecological nor a personal hazard.Waste management for a hard rock rare earth project includes the management of mineral processtailings, waste rock, and metallurgical residue. Proven strategies are available for tailings and waste rockfor all climate conditions. The management of the metallurgical residues is potentially more challenging.Example robust strategies for addressing these challenges are presented.A potential way to reduce the radioactivity of rare earth metallurgical wastes is to selectively remove uranium and thorium. Uranium oxide is readily marketable, but its concentration as a byproduct typically triggers extensive regulatory processes. Thorium is presently not marketable, but may be so in the not-too-distant future with the development of thorium-based nuclear energy. The pro’s and con’s of uranium and thorium byproduct recovery are summarized."

Jan 1, 2016

By P. James

"INTRODUCTION High sulfate (SO4-2) levels often occur in MIW (mining influenced water) either as the result of oxidation of sulfide minerals exposed by mining activity or by deliberate addition – commonly by sulfuric acid (H2SO4) use in hydrometallurgical leaching activities. Increasing regulation of sulfate discharge is creating new pressure to treat or mitigate sulfate release to prevent its entry into the environment. Current treatments include precipitating as gypsum during lime treatment, filtration separation using membranes such as reverse osmosis and nanofiltration technology, and biological elimination via methods like constructed bioreactors. Blue Planet Strategies (BPS) focuses on improved resource utilization targeting electrolytic treatment and waste conversion into resources and has now demonstrated that its proprietary DEMET™ (Dynamic Electrolytic Metal Effluent Treatment) platform can also remove sulfate from target streams as a byproduct of its usual primary treatment focus points of metal species elimination and/or pH adjustment.[1-6] This powerful new capability can mitigate sulfate contamination and recover the sulfate in a useful and potentially saleable form as a byproduct of improved primary treatments focused on enhancing production or treating waste. This provides a new treatment opportunity and value proposition for lowering overall sulfate consumption/addition or creating new revenue to defray conventional treatment costs. The DEMET Alternative DEMET utilizes a patented electrolytic technology platform employing proprietary dynamic high surface area electrodes in innovative configurations to achieve a variety of novel selective chemistries. DEMET‘s unique elements can yield higher processing rates at practical efficiencies, lower energy consumption, plus improved processing stability and lower maintenance requirements due to enhanced resistance to cell fouling and shorting; while also thwarting cross stream (catholyte vs. anolyte) contamination. Consequently, DEMET can provide a superior, extremely versatile, and cost-effective electrolytic treatment option where a multitude of FEED and PRODUCT stream combinations might be employed in comparison to traditional tankhouse electrolytic cells. Secondary reactions (Figure 1A) which could also occur at the cathode (plating/electrowinning, precipitation/scale formation, etc.) are controlled through process tailoring and operation parameter selection. Additionally, DEMET‘s innovative dynamic system mitigates potential fouling and electrode occlusion or shorting challenges which could occur when process particulars demand some of these secondary side reactions occur."

Jan 1, 2015

By C. J. Bise

One area of study for the Coal Mine Injury Analysis project was to illustrate how loss control can be used as a foundation for mine safety training. After an initial review of the principles of loss control, the instruments often used for worker/worksite appraisal, such as incident reporting, analysis, and investigation, workplace observation, worksite inspection, and safety audits and checklists were evaluated for their effectiveness. The findings were then applied to the continuous-miner worksite at several mines to modify the techniques for use in a highly dynamic man/machine work environment. Before the information gathered from the review of the various continuous-miner worksites was presented at the annual retraining sessions at five mines, a trainability analysis procedure was developed to separate training shortcomings from those problems resulting from improper equipment design or unsatisfactory working environments. Also, several microcomputer-based training programs were developed to aid in conveying the loss-control concepts to the trainees. Finally, the results from the implementation and evaluation of the loss-control-based training programs were documented, including the complete training script for one of the case-study mines. The procedures outlined in this study will aid mine training specialists in developing focused, pro-active accident-prevention strategies and training programs that are based on sound loss-control principles.

Jan 1, 1993

By P J. B Fransen

Several spatially and/or temporally distinct phases of epithermal activity can be recognised in the Horohoro-Matahana Basin area of the Taupo Volcanic Zone. In the northern Matahana Basin a 140 - 350 ka age range is proposed for mineralised debris flow clasts and related (?) epithermal  mineralisation intersected in a recent drillhole. To the east, a ca. 40 - 50 ka age range is suggested for epithermal activity in the Waikaukau alteration zone which was focused along the Guthrie Fault. Hydrothermal explosion breccias occur over 13 km within the Guthrie Graben, and are probably sourced from vents in the south. Assuming a common origin, these breccias are constrained to a 45 - 50 ka age range. Within the Horohoro hydrothermal system (around the present hot spring), older (15 - 50 ka) and younger (0 - 15 ka) features can be distinguished.

Jan 1, 1991

Conditional simulation provides a model of the ore body that represents variability in the data. This can be used to determine the impact of various grade control and mining strategies. A number of transfer functions are discussed that assist in optimizing grade control sampling. The cost effectiveness of various drilling and trenching techniques are discussed. Modelling of the expected performance of a mill head grade sampler is investigated. Conclusions are drawn about the likely impact of various sampling techniques on the economic performance of an operation and about applying sampling theory to grade control sampling.

Jan 1, 1999

By A. G. Rozner

TRANSVERSE rupture tests have been commonly used in mechanical investigations of brittle materials. The specimens are simple, easy to prepare, and loading presents no difficulty. Owing to the complexity of stress distribution in bending1 one can determine stresses rigorously only for the elastic range. The bend-test results, however, are at times converted into tensile-strength data, determined as maximum fiber stress. The assumption is made that for small plastic deformations the linear stress-strain relation applies. This problem was experimentally investigated by Bach3 who tested cast iron in bending and in tension and found that the maximum fiber strength obtained in bending exceeded the experimental tensile strength by a factor depending on the geometry of the tested piece. The factor varied from 1.57 for a rectangular cross section to 2.12 for a circular cross section of the tested beam. Since this work was carried out 60 years ago, the cast iron used could be expected to have been highly brittle, thus the extent of plastic deformation prior to fracture very small. We have therefore carried out a number of tests on magnesium-modified cast iron with an average elongation of -5 pct. It was hoped that the data obtained from the tests would serve as a guideline for comparing data obtained in tension and bending for brittle materials. Mechanical properties were measured at room temperature on an Instron tensile machine at a crosshead speed of 0.05 in. per min. The three-point bend test employed cylindrical bars 0.20 in. in diameter with a 1.0-in. span. For the tensile test, cylindrical tensile specimens with a gage length of 0.85 in. and a diameter of 0.160 in. were used. Results are summarized in Table I. From Table I one can see that fracture strength

Jan 1, 1965

By Bruce A. Kennedy

The place of the young engineer in the mining industry has been the subject of a large number of keynote addresses, magazine articles, and papers in the past year. One of the best of these was the keynote address given by Mr. J. C. Kinnear, Jr. at the Fifth Annual Intermountain Minerals Conference in Vail. Colorado. Mr. Kinnear presented as part of his address the statistics of a Canadian survey Instigated to find out why young engineers and geologists are leaving the mining industry. The results of the survey showed four main reasons for leaving: 1) insufficient money 2) slow promotion 3) lack of association with senior engineers, as well as insufficient opportunity to keep abreast of technological development 4) geographic isolation

Jan 1, 1970

By V. Reiter, K. Reinharter, C. Wenzl, D. Gregurek, A. Spanring

The refractory linings in lead furnaces are exposed to several stresses rather complex in their interaction. In the present study the magnesia-chromite brick out of a lead recycling furnace suffered from a high chemical attack by the process slag. The high CaO, BaO and sulfur bearing silicate slag, as well as a high NaO2 supply from soda resulted both in a deep-reaching infiltration of the brick microstructure and a severe corrosion of the brick components. Both the sintered magnesia and chromite were attacked chemically. The FactSage calculations showed the formation of high amounts of liquid phase in the infiltrated microstructure. Further phenomena affecting the refractory performance such as iron oxide attack, redox effects, and boron attack are also discussed in the paper. The obtained information and insights serve as a basis for improving refractory materials (i.e., choice of refractories for individual process and new developments) and consequently furnace operations.

Mar 1, 2017