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By Bruce Conard

For many years, Bruce Conard has been engaged in reading about and discussing the desired sustainability of the mining and metals resource industry. He has, however, become concerned that there is a greater issue that requires our urgent attention: what challenges do we face as a global society? His Distinguished Lecturer presentation traces the idea of environmentally sustainable economic development but concludes that a business’ interest in its sustainability is predicated on the sustainability of our global society. Conard reviews some of the most serious challenges, including population growth, clean energy supplies, freshwater availability and climate change, and calls on scientists and engineers not only to apply their skills in helping solve these challenges, but most urgently, to speak with intelligence and passion about the need to act now.

Jan 1, 2014

Recent literature is reviewed with emphasis on the design and scale up of mixers. Most important aspects of mixing have resulted from the study of Newtonian fluids and only a minor attempt has been made to extend the work to non-Newtonian materials.The rheology of non-Newtonian materials is outlined and the typical behaviour of mineral slurries is indicated.The importance of flow velocity, flow pattern, and fluid turbulence is discussed with relation to suspension of solids and rate of reaction.Data on experimental leaching of ore from Mary Kathleen, Queensland, show the effect of different mixing impellers.In conclusion, factors involved in the selection of a mixer are presented with emphasis on economic appraisal after pilot experimentation.INTRODUCTIONThe subject of mixing has attracted considerable attention during recent years, but relatively little work has been undertaken for the study of non-Newtonian materials. Most work has been restricted to Newtonian fluids because there are less inconsistencies in such study.Mixing, by definition, implies blending or combining, and ranges from gentle mixing which blends the contents of a large tank in 24 hours to violent mixing which completely homogenises the contents of a tank within seconds. Metzner and Otto (1957) have pointed out the present lack of knowledge on the degree (or quality) of mixing. Apart from this fact the design of mixers for Newtonian materials would seem to be reasonably certain.Both capital and operating costs rise rapidly with increasing mixer size. Therefore the design, or selection, of a mixer is a matter for economic consideration in the overall aspect of plant design and operation.

Jan 1, 1961

"In addition to outstanding technical sessions and networking opportunities, the SME Annual Conference and Expo offers attendees a chance to see the latest and greatest technology that the industry has to offer. The 2017 SME Annual Conference and Expo was no exception as 575 companies filled 756 booths from Feb. 19-22 in Denver, CO. The following is a look at some of the vendors that were on hand.AIL MiningThe Edge, featured by AIL Mining at the 2017 SME exhibit, is a four-flange structural liner designed to be an alternative to structural plate’s traditional lapped seams and to help mine operators build more efficiently and safely. It is ideal for creating underground structures, such as mine shafts, ventilation raises and escape ways. The Edge is available on SuperCor structural steel plate — 10 times stiffer and five times stronger than traditional steel liner plate. It facilitates curved structures, both horizontal and vertical, and eliminates the need for ring beams. It is ideal for remote sites. For added safety, structures can be assembled from the inside, and the leak-resistant structures can be dismantled and removed easily. Brackets can be attached to mine shafts or vent raises to support Alimak rails or climbers. Similarly, brackets or hangers can be attached to drifts or tunnels to support mine air, water or electrical utility services.ArcadisMining companies spent nearly $12 billion on water infrastructure worldwide in 2014, reflecting the industry’s heightened concern about environmental issues and social, regulatory and political risks.So, with an increasing focus on water reuse and recycling, mining companies must have effective water management plans that include sustainable solutions. Also, many water quality issues fall under both state and federal regulatory jurisdictions. To solve these problems, Arcadis provides comprehensive ground- and surfacewater technical support in a complex hydrogeologic setting. It can characterize the nature and extent of mine-related constituents in ground water and surface water, as well as the complex interactions between the two waters, and prepare the operational permits needed by mine and tailings facilities. As an example, Arcadis constructed a hydrogeologic and geochemical conceptual site model that improved site understanding for a molybdenum mine in the western United States that spanned several watersheds. It also provided technical support for permitting and compliance issues, allowing the mine to return to active production."

Jan 5, 2017

By Dhar B. B, Gupta R. C

Grinding of iron ore is an essential step to utilise ore fines for pelletisation needed for DRI units. While preparing iron ore pellets for DRI production, the iron ore needs extensive grinding which is highly energy consuming step causing the process to become non-viable in some cases. In the present paper an attempt has been made to evaluate grinding performance of thermally treated ore compared to normal ore grinding. Such thermal pre-treatment has been found to reduce the energy requirement with lower consumption rate of grinding media. It has been observed that by applying thermal shock the ore is rendered weak with improved grindability. The stresses generated due to thermal treatment may extend existing micro-cracks in the ore and in some cases it may even nucleate fresh cracks. Experimental studies carried out on thermally treated hematitite ore reveals that the heating to 400¦C followed by water quenching can cause a reduction of 45 per cent in grinding energy. The paper gives the details of the experiment and the Results.

Jan 1, 1999

By Damian R. Siebert

Risk-reduction measures implemented during the design and construction of a 21-story pile-supported building adjacent to a below-grade 100-year-old sewer structure were keys to a successful foundation system. Avoiding damage to the existing sewer structure during construction activities and the future ability to access the structure post-construction were the main concerns for the utility owner. Clear communication and a deliberate design process between all parties ? utility owner, building owner, structural engineer, geotechnical engineer, architect, and contractor ? were integral to the project?s success. This collaborative process helped all parties to understand the risks, both real and perceived, and to develop mitigation measures to reduce the risks. Bringing together all parties to engage in dialogue and encouraging open communication throughout the project were paramount to its success. By implementing the joint design plan, using mutually-acceptable construction techniques, and careful monitoring, the building foundation was successfully installed and all parties? risks were averted.

Jan 1, 2011

By L. A. Eros

The U.S. Bureau of Mines and Western Fuels Utah, Inc. entered into an agreement to plan, install, and evaluate a micro-computer based monitoring and control system at Deserado Mine, an underground coal mine. The U.S. Bureau of Hines contracted the Colorado School of Mines (CSN) to independently evaluate the project. CSM evaluated and documented costs, benefits, problems, and management and labor perceptions in this report. Recommendations are provided for mine operators and monitoring system vendors considering future installations.

Jan 1, 1986

By Ö. Erdem

The investment decision making process in the insurance and finance industries is affected by new advances such as simulation techniques. These advances have improved the discounted cash flow method (DCF). In DCF, a dynamic and flexible model construction is not possible because it does not consider uncertain conditions. Each project should be evaluated taking into account the related uncertainties because the related uncertainties determine the characterization of the project. Related uncertainties can be processed in dynamic DCF, which is applicable to both financial and non-financial industries with different kind of uncertainties, such as power generation and petroleum projects. The dynamic DCF method can estimate net present value (NPV) while managing related project uncertainties with a simulation method like Monte Carlo Simulation. The simulation method is preferred because its output is unbiased. Therefore, a more realistic financial evaluation of the project can be concluded. In spite of the improvement of dynamic DCF, this project evaluation method is not used frequently in mining industry. However, the mining industry is ideally suited to this concept because it is highly dependent on estimations such as orebody size and ore grade. During the project evaluation stage, these uncertainties can be included with the dynamic DCF method. This study aims to contribute to increasing the usage of this method in mining projects. A copper reserve in Turkey is selected as a case study to apply uncertainty assessment for the evaluation of NPV.

Jan 1, 2012

CONTENTSSummary.Introduction.Location and Geology.Historical and Exploitation.Part 1. Washability Characteristics of the Liddell.Seam.Foybrook Open Cut, Top Bench.Sampling.Size and Ash Distribution.Washability Data.Washery Separations.Part 2. Washability Characteristics of the LiddellSeam.Foybrook Open Cut, Bottom Bench.Sampling.Size and Ash Distribution.Washability Data.Washery Separations.Acknowledgments.References.INTRODUCTIONThe washability characteristics, size-range and chemical analyses of the screening from the Liddell Seam are matters of growing interest in view of the increased exploitation of this seam over the last few years, and also since the Newdell Coal preparation plant of the New South Wales Mining Company Proprietary Limited, utilizing magnetite heavy media separation, commenced...

Jan 1, 1954

Real-Time Integration of Mining and Metallurgical Information for Efficient Use of Energy and Water

Sep 13, 2010

The Greymouth Coalfield contains New Zealand's greatest known resource of bituminous rank coal. The coals are of very high quality, with low ash and sulphur contents and a range of other properties that makes them desirable for a wide range of uses. In fact only a few producers around the world today can offer coals with such exceptional properties. This suggests that Greymouth coal has potential as a premium export trading commodity. These assertions have been largely confirmed by a comprehensive exploration drilling programme funded by Mines Division û Ministry of Energy between 1979 and 1984. The program, forming part of the NZ Coal Resources Survey, was carried out under contract by Lime and Marble Ltd. The drilling of 49 deep, predominantly cored, holes at 1000 m intervals over the coalfield has generated a vast amount of data. It has shown the existence of three major potentially minable coal deposits containing 233 x 106, 33 x 106 and 15 x 106 tonnes of coal in ground. Investigations have at this stage only identified targets and these estimates represent 'in ground' resources, not recoverable reserves. Recent geological studies as well as past and present mining have clearly highlighted the problems posed by the complexity of the coalfield geology. The coalfield lies within a mobile zone in the earth's crust known as the Paporoa Tectonic Zone, which has been active from at least mid-Cretaceous to the present time. Currently this factor poses the greatest obstacle to the determination of mining possibility of the, defined deposit and ultimately will strongly influence any future mining development. The Greymouth Coalfield has, however, had a long and eventful mining history spanning the last 120 years, where 32.5 x 106 tonnes of coal has been won from over 100 mines. In spite of the problems facing development, the large quantities and exceptional quality of the remaining coal will act as a strong inducement to persevere with this difficult but potentially valuable resource.

Jan 1, 1985

By R. F. Favreau, Patrice Favreau, Dennis Mahan

Cast blasting is becoming more and more popular, not only in coal mines but also in other operations which require excavation of an upper layer of waste rock to uncover temporarily and excavate a layer of ore, which may for example be material for the fertilizer industry.

Jan 1, 2014

By D. Harrington

"Coal—mine explosions are accidents that can and should be prevented. In former years hundreds of lives were lost each year in the United States as a result of such explosions, but after 1932 the numerous precautionary measures adopted had reduced their frequency and severity 75 percent or more until in 1940 several very disastrous explosions marred the good record. Unfortunately, both the number and severity of explosions seem to be tending to increase compared with the relatively good achievement from 1933 to 1940. The requisites for an explosion are ever present in all soft-coal and many hard-coal mines. A certain combination of circumstances, such as a flame or an arc in a cloud of dust or in a body of gas or both may start an explosion at any time. The fact that the frequency and severity of explosions were lowered for 6 or 7 years is no guarantee that such freedom from explosions will continue, as the bad record of 1940 has shown, and underground workers should feel honor bound to exercise the utmost care so that they will not help to bring about the circumstances that will cause an explosion.Although mine operators bear the main responsibility for preventing explosions, miners can do many things to help. As about 9 out of 10 explosions begin at a working face, it is largely within the power of workers to prevent them. All miners should do their part willingly and should not defend a fellow workman from punishment, even from discharge, for disobeying necessary rules, whose disregard may cause the death not only of the safety-rule breaker but also of many of his coworkers.When a miner is careless and is injured some other way than by an explosion he may be the only one to suffer, but if his carelessness causes an explosion he not only endangers his own life but also that of every other man in the mine and possibly the lives of persons outside the mine.Experiments have shown that ignition of as small a quantity as 150 cubic feet of an explosive mixture of methane and air under certain circumstances can start an explosion that will traverse an entire mine. Thus, ignition of an explosive mixture of gas 1 foot down from the roof and 13 feet back from the face of a 12-foot entry might cause a widespread explosion if the right quantity and kind of dust were present. Many persons have ignited much larger quantities of gas without being killed, but they survived only because dust, confinement, and other conditions were not exactly ""right."""

Nov 1, 1940

By B. C. Peterson

Calumet Division, Calumet & Hecla, Inc., whose operations are in Houghton and Keweenaw Counties, Mich., is a highly integrated and complex organization. This division operates mines, a railroad, a concentrating mill, a reverberatory smelter, and the auxiliary generating plants and shops to service these operations. In addition, it operates a sands reclamation plant, leaching plants, a foundry, and a machine shop that serves varied industries with castings and parts for many applications. Calumet & Hecla, Inc. has produced over 60 percent of all the copper that has been produced in Michigan since discovery of the ore in 1864, and in 1959 the company ranked eight among the country's producers with a production of 17,407 tons. To keep abreast of modern accounting systems developed elsewhere in industry and to combat increasing costs due to higher labor and supply costs, as well as increased costs due to deeper mines and lower grade ore, the company has developed a modern machine cost accounting system. This not only provides the usual bookkeeping and cost accounting facilities but offers accurate cost data for engineering evaluation of the mining operation. This system is credited with being instrumental in permitting continued operation of these high-cost mines in a period of increasing costs with no corresponding increase in the price of metal.

Jan 1, 1962

By A. M. Ouchi

Existing empirical design tools have been developed from fair-to-good quality rock masses (RMR76 >50). This paper presents a focus of ground control research presently being conducted by the Rock Mechanics Group in the UBC Mining Department in incorporating weak rock masses (RMR76 <50) into existing empirical design relationships. An emphasis is being placed upon the updated span design curve/critical span graph originally developed at UBC. The original database has been augmented with over 450 weak rock data points from mines such as the Stillwater mine (Montana), the Eskay Creek Mine (BC) and several mines in the Carlin Trend and other parts of Nevada. The original database is comprised of spans supported with ?traditional? mechanical bolting. In weak rock environments however, this type of support has been found for the most part, ineffective. This paper presents the span and weak rock RMR76 relationship for four different support categories. This work attempts to provide rock mechanic tools that will enable a mine operator to make economic decisions that will also ensure a safe working environment.

Jan 1, 2008

By R. W. Raymond

(Pittsburg Meeting, March, 1910.) IN the long list of our illustrious and lamented dead, there are names which recall personality as well as career and achievement; social as well as scientific merit; devotion to the Institute itself as well as to some one of the professions which it represents. These men we remember because they did not forget us; besides our pride in their wider work and fame, we are proud of what they did with and through us; especially do we rejoice if our early recognition of them opened the way to a recognition by the world; and in their departure we claim to sorrow, not merely as members of an appreciative public, but also as. bereaved personal friends. In common with thousands, we regret our loss, but we do not regret only-we mourn and miss. To this group of those whose death has brought to us the double sense. of public and private grief belonged our strong, bright, dear brother, in whose memory this inadequate tribute is offered. Charles Benjamin Dudley was born July 14, 1842, at Oxford, Chenango county, N. Y. He came on both sides of New England blood, his father being from New Hampshire and his mother from Connecticut. Emigrating from the rocky hills of their native States, they. settled upon the more fertile soil of what was then regarded as the West, and, with thousands of other pilgrim sons, imitating the pilgrim fathers, contributed to the foundation of new commonwealths. The Empire State owes much to this element of its population. Dudley&apos;s early education was obtained, like that of the sons of the pioneers generally, by attending the village school and academy in the autumn and winter, while he worked upon the farm during the rest of the year. But his ambition looked forward to a college-course; and this was almost within his reach when a passion still stronger took possession of him. The out-

Jun 1, 1910

By R. W. Fedors, S. T. Green, G. R. Adams, C. Manepally, L. B. Browning

This paper provides estimates of large-scale temperature gradients that can be used to support modeling of natural convection and cold-trap processes in thermally perturbed drifts. Temperature influences estimates of the quantity and chemistry of water contacting engineered components (e.g., drip shields and waste packages) in a potential high-level waste repository at Yucca Mountain, Nevada. Temperature gradients drive natural convection and cold-trap processes, which could affect the distribution, quantity, and chemistry of liquid-phase water contacting drip shields (waste packages).The confluence of high temperatures, liquid-phase water, and high chloride may lead to corrosion of drip shields and waste packages. An overview of the evolution of environmental conditions in thermally perturbed drifts is presented to provide a context for the estimates of temperature gradients. A mountain-scale conduction-only model is used to estimate temperature gradients and temperature differences for a drift located at the center of a potential repository. Thermohydrologic models and heat transfer algorithms are used to evaluate the reasonableness of the conduction-only results. Estimates of temperature using an in-drift heat transfer algorithm account for the possibility of drift degradation and formation of a rubble pile on the drip shield. Temperature differences between the center and ends of the drift are estimated to rapidly increase to 80 °C soon after repository closure. That temperature difference decreases over time to 15 °C after 10,000 years. Local temperature gradients are generally estimated to be less than 0.2°C/m, though the gradients can be much larger near changes in lithology and near the end of the drift. The estimates of temperature gradients do not account for intermediate- and small-scale variations, such as those influenced by differences in heat loads between waste packages, intra-layer variations in thermal properties of the surrounding fractured rock, or localized drift degradation.

Jan 1, 2004

By Larry DeGraff

With the increase of new mine development in the past several years, many coal mines have decided to self- perform the design and construction for their slope development projects. The development process of determining the proper configuration is challenging, and a major economical consideration. Greenbrier Smokeless Minerals engineering staff and consultants, along with DSI/American Commercial, developed a support configuration that was best suited for their slope. The developmental process took into consideration the length of slope, depth of slope at the high-wall transition, economics of a single or multiple entries, waterproofing, stresses on the steel supports and lagging during the backfilling operation. This paper describes the developmental concept of using a single entry, side by side configuration, using steel ?Banjo String? supports with steel plank lagging, to develop a long term permanent installation in a cut and cover application.

Jan 1, 2009

By John S. Brown

The northeastern United States embraces that area of the Appalachian Mountains, and adjacent territory, beginning on the south at the Potomac River. It thus extends from the flat-lying Paleozoic terrane of the Appalachian plateau on the west, across the folded Paleozoics of the Great Valley and adjacent ridges (Paleozoic and Precambrian), over the Piedmont and New England metamorphic complex (mixed Paleozoic and igenous rocks), broken by the great Triassic rift remnants, onto the subdued coastal plain of Cretaceous and Tertiary sediments. Although not noted as a metal mining region, the area does contain numerous substantial and several outstanding mines, chiefly of the more prosaic metals, particularly iron, zinc, and copper, as well as many minor occurrences of these and a few additional items. These deposits occur to some extent in every subdivision of the area. The region to date (1966) has produced almost 500,000,000 tons of medium to lowgrade iron ore, especially magnetite, including ilmenitic magnetite; 50,000,000 tons of highgrade zinc ore; and 5,000,000 tons of lowgrade copper. In the past, it has yielded small amounts of chromite and nickel, and at present is a large producer of titanium. Precious metals are conspicuously absent, and so also are the Tertiary or Mesozoic igneous phenomena so commonly associated with mines of the West. Hence, a survey of the extensive mineralization · of this region should be instructive

Jan 1, 1968

Jan 1, 1968

The pressure of low commodity prices forced the design process for the second lift of Northparkes E26 Mine to adopt a continuous improvement philosophy. The emphasis was to minimise capital expenditure while still maintaining the excellent low operating costs achieved on Lift 1. Although the first block cave lift at Northparkes is the most productive underground mine in the world and is held up as a benchmark for the use of technology in mining, areas for improvement were identified. Every area was critically assessed and investigated for the possible application of new techniques and technologies. Key learnings from the construction and production phases of Lift 1 were captured, documented and used as the starting point for the Lift 2 design. This paper shows how and why the design parameters initially used onLift 1 were changed to become the current E26 Lift 2 developmentproposal. The main differences between the two block caves arehighlighted. The alternative techniques and equipment that wereconsidered are also discussed. * Originally published in the Proceedings of MassMin 2000,published by The AusIMM.

Jan 1, 2001