Search Documents

By C. H. Stephenson, Z. White

This paper presents the design approach case study for incorporating a Technogrid® conveyance End-of-wind arresting system within the new South32 Hermosa headframe. Focus is placed on energy absorption requirements, structural integration, and mounting details tailored to the geometry and operational constraints of the headframe. Key considerations include arresting forces, load path continuity, and connection design to ensure reliability and maintainability. The paper also discusses coordination with other headframe systems and the iterative design process used to meet safety standards and client objectives.

Feb 22, 2026

By M. Allan Holtz

The shipment of coal, ores, and minerals in bulk form during the winter months presents a difficult problem in emptying rail cars. U. S. Steel Research in cooperation with U. S. Steel Coal Operations bas laboratory tested and field monitored the effectiveness of using freeze conditioning agents (FCA) to minimize the frozen coal problem. This report examines, in an overview manner, our experience after four seasons of treatment using different FCA agents on raw and preparation plant products. Our observations indicate that if an FCA is applied correctly it is effective mineral to mineral. Freezing problems still occur at the interface between the coal and the metal of the car sides and bottoms. Leading chemical suppliers have made positive improvements in their FCA formulations with second and third generation products. Further advances are needed to make chemical treatment for the prevention of frozen coal a real full-proof method.

Jan 1, 1980

By Brendan Howard

Rio Tinto has a large globally distributed technical workforce and needs to ensure these employees have the requisite skills to not only manage technical risk and enable safe efficient production, but also ensure they are keeping pace with a fast-changing technological landscape. Traditional approaches to learning struggle for scale and an inability to respond to the extreme diversity of capability development needs. In response, Rio Tinto has successfully introduced innovative approaches to learning and employee engagement via leveraging the power of globally distributed networks for peer-to-peer knowledge transfer and providing mechanisms to recognise, reward and retain the individual technical contributors.

Feb 1, 2024

By Sabina Brady

Nearly a decade and a half after the US and China established formal diplomatic relations, and two decades after the two countries signed the Shanghai Communique and established commercial ties, the world, and perhaps China itself, has discovered that a wealth of natural mineral and energy resources lie beneath China's soil and directly off its coast. The country's coal reserves and oil and gas potential are well known. Its ferrous and nonferrous metal reserves are respectable and in a number of instances pre-eminent. According to 1981 Minerals Yearbook estimates - more often than not below those now being claimed by China - the country's aluminous metal reserves are about 907 Mt (1 billion st); iron ore reserves are 40 Gt (44 billion st); and copper reserves are about 46 Mt (54.4 million st) of contained metal. In addition, the country has about 10.7 Gt (11.8 billion st) of phosphate reserves, the fourth largest in the world, and 3 Gt (3.3 billion st) of pyrite. China's national Sixth Five Year Plan promulgated in late 1982 ended a stringent three-year retrenchment or readjustment period in which a number of major development projects involving foreign participation initiated in the late 1970s were shelved. The new Five Year Plan is a signal both within and outside of China that things are now moving again, and that major industrial and service sectors are receiving the kind of funding and flexibility they need for expansion, construction and modernization. The new plan's strategy for growth is measured and much less grandiose and frenetic than it was five years ago when China flung open its doors to foreign companies and invited participation in large-scale development projects. Now, the country's reticence to spend foreign exchange to purchase key equipment, technology, and services -a reaction to these projects and the spending they entailed - is clearly on the wane. In China's effort to quadruple its GNP by the year 2000, there is a new willingness to use some of its substantial foreign reserves. In fact, it is projected that 1983 will witness a $1.9 billion deficit, with a $2-3 billion deficit in 1984 and 1985. The following article discusses implications the Sixth Five-Year Plan has for nonferrous metal development in China. It is the first in a series of three articles on Chinese mineral resource development to be published in Mining Engineering over the next few months. The second article will identify specific nonferrous projects underway, while the third in the series will focus on trade and development opportunities for phosphate and potash producers in China. China's Ambitious Plans In the last few months, the exploitation of China's nonferrous resources and development of its industrial processing capabilities have begun to receive increasing attention on both provincial and central levels. Unlike the earlier modernization drive of 1978 when China's ferrous sector - best typified in the Baoshan iron and steel project - got the lion's share of the Ministry of Metallurgical Industry's (MMI) energy and resources, it now appears that in some respects the nonferrous and industrial sectors are finally moving out from beneath the dominating shadow of ferrous and getting their own day in the sun. Separation of Nonferrous from Ferrous One clear demonstration of this is the establishment in April 1983 of the China Nonferrous Metals Industry Corporation (CNFMIC). The corporation is composed of 819 enterprises with over a million workers, and also includes 12 nonferrous metal construction companies, eight design institutes, and three prospecting companies. Of ministerial rank, CNFMIC is responsible for the development of both the country's nonferrous resources and its processing facilities. Although closely tied to the parent ministry from which it sprang (i.e. MMI), CNFMIC, at least theoretically, is separate and independent from it. One strong indication that this independence is, or soon will become a reality, can be seen from the fact that the new corporation is not headed by the former MMI officials, not even those who made up the ministry's now defunct nonferrous bureau. Instead, its president Qiu Chunfu is formerly of the State Economic Commission and the China International Trust and Investment Corp. Its general manager Fei Ziwen, an engineer in his early 50s, is from the Jiangxi Province Copper Corp. The new nonferrous corporation appears to be powerful

Jan 7, 1983

The mining industry is one of the three pillars of the Namibian economic development, besides tourism and the fishing industry. Generating 20 % of the GDP and more than 50 % of the export income, half of this amount derives from the diamond mining industry. In 2008, the annual production of 2.2 mio carat achieved an income higher than 1.44 billion Namibian Dollars (more than 750 mio Euro). After the global recession in early 2009, which also caused a significant downcrease in production to only 0.93 mio Carat, the diamond mining industry easily restored itself and the production figures for 2010 are expected to be even higher than those achieved in 2008. Compared to other diamond producing countries, Namibia is mainly producing diamonds of highest quality (jewellery quality), with less than 10 % of the mined diamonds not falling into this category. This high quality stands also for the worldwide highest prize achieved per carat. With 370 $US per carat it is more than four times higher than that of the average South African stone. In 1908 the finding of the first diamonds in the Namib desert close to the coastal town of Lüderitz was reported by a Mr Stauch, railway inspector for the then German colonial railway company. This event immediately triggered a Diamond Rush and subsequently the set-up of the restricted diamond mining area ?Sperrgebiet? through the German colonial administration. In 1913, only five years after the first mining operations had started, the steadily increasing production allowed for more than 20 % of the diamond production worldwide. After the First World War, the new South African government concentrated all mining activities in one organization, CDM (Consolidated Diamond Mines of South West Africa) which in following decades conducted an extensive and detailed exploration of the whole Sperrgebiet and started numerous new diamond mining operations.

Jan 1, 2011

By William Gleason

"It has been more than 10 years since Montana Resources’ copper/molybdenum mine has had a lost-time injury at its site in Butte, MT. With more than 350 employees and an average production of about 15.5 Mt/a (17 million stpy), which includes 29.5 kt (65 million lbs) of copper and 4 kt (9 million lbs) of molybdenum, the mine’s journey to a decade of exemplary safety is an impressive feat that has required hard work, commitment and, most of all, leadership from every level of the operation.It has not always been an easy journey, nor has it been one without scrapes and bumps along the way, but it is one that has produced stellar results. Mike McGivern, vice president of human resources, and Pete Steilman, safety manager at the mine, spoke with Mining Engineering about how the operation transformed from a site that was accustomed to collecting citations for safety violations to one that is now collecting awards for its safety record.Simply put, Montana Resources has made safety a value and the people its top priority.The operations faced many predictable challenges in 2003, when the mine was being brought back online after three years of sitting in care-and-maintenance status. It had been shuttered in 2000 because of low commodity prices and high operating costs, and, in the three years that the mine was idled, the equipment became dilapidated, and some of it was no longer in compliance. Less than half of the workforce returned to the site for the restart, and the team was challenged with getting the gears turning again to produce copper and molybdenum. But the most daunting challenge of all of was keeping the workforce safe during the transition.In the first few years of operation the mine racked up citations from the U.S. Mine Safety and Health Administration (MSHA) at an alarming pace, so much so that in May 2006, Montana Resources received a letter from the MSHA District Office informing the company that the operation was being placed on the Potential Pattern of Violations list due to its excessive citation history and high rate of significant and substantial citations. It was clear that something significant had to be done to change the course of action at the mine."

Oct 1, 2019

By John J. Stetler

The Companhia Vale do Rio Doce in Brazil operates one of the most extensive systems in the world for the mining, transportation, processing, pelletizing and shipping of high grade hematite iron ore and pellets. Current shipping of unbeneficiated, sized, high grade ore from its ports at Tubarão and Vitória is now at the rate of 17,500,000 metric tons annually. An increase in this annual rate is now under study. Using the technology and facilities of Lurgi (1) and Arthur G. McKee company CVRD undertook a program to process and pelletize two types of fines - "Blue Dust" and ?Itabira Fines?. Blue Dust is a high grade fine ore which was bypassed while mining the direct shipping ores and which, also, exists as a very large ore body called the Conceição Mine. Itabira Fines is a lower grade of fine ore which is comprised of in-situ fines and, also fines which are generated in sizing the direct shipping ores for a rigid specification market.

Jan 1, 1970

By Joel S. Leventhal

The roles of organic matter in ore deposits are complex and represent a specialized effort in the larger subject of the geochemistry of ore deposits. The organic carbon cycle can be considered with particular emphasis to ore deposits in order to understand the origin and genesis of the organic matter. Organic matter may play one, several, or none of the following important roles in the formation of ore deposits: leaching, transport, concentration, reduction, and precipitation of metals. For deposits that contain organic matter, detailed field relationships and laboratory characterization of the organic matter are required to make an ore deposit model that Includes the organic matter and specifies its role(s). Examples of the involvement of organic matter in several types of uranium deposits are contrasted as being direct or indirect, syngenetic or epigenetic, and necessary or unnecessary. Examples of organic matter in deposits containing gold and lead-zinc, and In metal rich shale are discussed with respect to ongoing work and critical questions.

Jan 1, 2013

By Stephen J. Crittenden

Deep gas and oil production has been substantially increased over prolonged periods through the use of sintered bauxite propping agents. Since its inception in 1976, over 170,000,000 pounds of high strength ceramic proppants have been employed. Recent field evaluations and economic analysis demonstrate the superiority of sintered bauxite proppant over quartz sand. This paper describes the development, application, field results, and product evolution of sintered bauxite.

Jan 1, 1983

By Paul C. Miclea

With the growing urban population and the concern for traffic congestion and pollution (emissions control), public transportation is becoming more and more attractive to both city dwellers and managers. To gain access to the central area of the city, the sub- way remains the most viable alternative, despite its higher cost when compared to above ground or elevated transportation systems. There are relatively few regulations and criteria for subway ventilation, particularly when compared with mine ventilation. The main document that provides guidance and general recommendations for subway ventilation and environmental control is the Sub- way Environmental Design Handbook, published in 1976 (2nd edition) by the U.S. Department of Transportation, Office of Re- search and Development. Many of the subway systems in existence today have been designed and built with ventilation features adequate for normal train operation, but their design does not consider stringent criteria for such emergency conditions as a train fire in a tunnel. The National Fire Protection Association's Standard for Fixed Guideway Transit Systems known as NFPA 130 as well as the ASHRAE Handbook - HVAC Applications (1995) provide specific design and operation requirements for subway ventilation systems. Some of the existing, old subways are upgrading their ventilation systems to comply with the new regulations. The ability of a particular ventilation system design to provide adequate ventilation during normal and emergency conditions can be evaluated using computer modeling and simulation techniques. A train fire will cause a sudden change in the tunnel ventilation pattern by adding an unsteady and fast-growing source of heat. The hot air and gasses created by a fire will tend to flow uphill, possibly against the normal flow, producing a 'backlayering effect." To prevent this effect from happening, enough ventilation must be provided and the governing criterion to establish the required airflow is called 'Critical Velocity." Several software packages are available for special applications on tunnel and station ventilation as well as to model the spread of smoke and heat in case of a major tunnel fire, using Computational Fluid Dynamics. This paper presents the current issues in subway ventilation, as shared by the public transit community around the world, together with modern alternative design concepts vis-à-vis the more stringent emerging Fire-Life Safety criteria. Examples of recent studies and ventilation systems design are provided.

Jan 1, 1997

By Allan M. Johnson

Dewatering is a major operational cost at sane mines. Under certain conditions, costs associated with water disposal may continue beyond the productive life of the mine. For mines with mineralized waters, this is of special concern. Since 1974 experience has been gained from the examination of a number of closed underground metal mines that exhibited drainage problems. It was observed in certain cases, that had appropriate steps been taken prior to closure, that the resulting drainage problems could have been largely avoided. The pre-closure steps would have involved alteration to the "plumbing system" of the mines: i.e., the drifts and crosscuts interconnecting the workings of the mine. This could have best been accomplished by the placement of bulkheads and/or selective drifting. In addition to reconfirming that hindsight is 20-20, a lesson learned from these case studies shows that a relatively simple hydrologic evaluation prior to mine closure may avoid a troublesome and costly drainage problem.

Jan 1, 1983

By F. J. Hurst

Phosphate rock, which is a prime source of phosphate used in fertilizer manufacture in the United States, contains uranium. In general, the uranium content of the rock increases with the phosphate content and most high-grade phosphate deposits (>30% P2O5) contain 0.01- 0.02% U3 8. The large tonnages of rock being mined represent a significant potential source of uranium that lends itself to recovery as a by-product of the wet-process phosphate industry. For example, in 1953, the U. S. Geological Survey estimated that recoverable phosphate reserves in the U. S. totaled about 5 billion tons and contained 600,000 tons of uranium. I This estimate did not include any rock from North Carolina which has since been estimated at about 2 billion tons. For the most part, the known, economically mineable U. S. reserves - estimated at about 7 billion tons - are concentrated in a few areas: 43% in the western states of Idaho, Montana, Utah and Wyoming; 28% in each of Florida and North Carolina and less than 1% in Tennessee. In the past, Florida has supplied about 80% of the total U. S. production, practically all of which is land pebble phosphate. All forecasts indicate increased production rates from North Carolina and the western states.

Jan 1, 1976

By John Hillman

The reconstruction of the British mining industry which began shortly after nationalisation in 1947 continued until well into the 1950s with the support of the Government. This support diminished as plentiful supplies of cheap oil from the middle East made many coalmines un¬economic. The planned rundown which followed was foreshadowed in the 1965 White Paper which outlined the financial measures to speed the closure of uneconomic collieries. The decline appeared likely to continue into the 21st century as the role of coal in UK energy requirements became less and less significant. This policy was well on course in 1973 when the oil crisis led to a complete reappraisal of the position. A Government examination in 1974 of the coal industry then supported the National Coal Board's general strategy of major capital investment as set out in its 'Plan for Coal' (1). Plan for Coal aimed at halting the intended decline in the industry's capacity and restoring it to 120 million tons of deep mined output in 1985. The Plan proposed action along the following lines (a) increase output by major Investment in construction at existing collieries with sufficient reserves to give 13 million tons per annum extra output (b) invest in extending the life of existing collieries by gaining access to additional reserves, to give 12 million tons per annum extra output © by sinking new mines, produce an extra 20 million tons per annum. Figure 1 shows the contribution (2) expected from each of the three sources up to 1990/1. The measures taken were expected to offset the inevitable exhaustion of existing pits and provide the additional 40-42 million tons capacity needed to restore annual output in 1985 to 120 million tons. Parallel to this programme for expansion of deep mined output, opencast mining was to produce 10-15 million tons per annum. A recent review however, indicates that new mines are likely to yield only 10 million tons per annum by 1985, mainly owing to the need for public inquiries into proposals for new mining and the resultant fact that planning approval takes 'much longer than originally expected. Nevertheless the objective of 120 million tons deep mined output by 1985 is still considered achievable of means of a greater contribution from existing mines. This programme was originally estimated to cost 2,-56 million dollars at March 1974 prices, out revised estimates of the cost of Plan for Coal indicate that it may now exceed 6,960 million dollars at mid-1977 prices. Plan for Coal includes a substantial investment in new and reconstructed coal preparation plaints. At mid-1977 prices more than 322 million dollars Ls so be invested in coal preparation projects in the UK, at the rate of, about 70 million dollars a year. This rate 3f capital expenditure has been maintained over the past three years and covers investment in a wide range of coal preparation coals for the power station, coking and domestic markets.

Jan 1, 1978

By A. Guzman

The design and construction of a new 140-ton-per-day R. O. M. phosphate rock scrubbing and washing plant was undertaken by Western Knapp Engineering Company, a Division of Arthur G. McKee and Company, for the J. R. Simplot Company, Minerals and Chemical Division, Pocatello, Idaho. The new plant replaces the owner's existing facilities at Conda, Idaho, seven miles northeast of Soda Springs in the southeast corner of Idaho. Replacement of the existing facilities became necessary because of loss in production and recovery. These losses were due in part to varying grades of raw ore from the mine and to the type of process equipment used in the old plant to upgrade the ore. Increase In production and grade was further necessary by demands created by expansion of facilities in Pocatello, Idaho, where all process ore from this plant is shipped. The new process scheme includes an ore-feeding system, scrubbing, screening, classification, wet cycloning, attritioning, filtering, drying, storage and shipping facilities. Space was also left for future increases of scrubbing and classification capacity and for heavy media separation. It is the purpose of this paper to take up some of the considerations necessary in the design of small mills in order to achieve the desired objectives of a successful plant, such as production, minimum operating cost and maintenance cost.

Jan 1, 1969

By Thomas W. Mitcham

A program of geological research in support of mineral exploration efforts is outlined. Specific goals are stated, approaches to accomplish their attainment are described, and the type of useful results to be expected are outlined. Because mineral exploration or prospecting has intensely practical goals, research in support of it must be applied research, applied to the problem of maintaining or increasing the discovery rate of the exploration effort. To attain research goals, attention to personnel selection, group structure, and program are critically important, and in about that order. A large percentage of the professional personnel should have had experience in mining geology or mineral exploration, and they all should be prospector-oriented. Structuring in the group should be at a minimum, with wide allowance for the kind of independent research which is essential to the nurturing of on-target creativity. The program should be field-oriented, and it should include a wide representation of those subdisciplines of geology which are applicable to mineral exploration. The types of results to be anticipated include improved or new conceptual models for various types of orebodies and their settings from which new ore guides can be derived, new exploration techniques, and the development of a knowledge bank for various aspects of the exploration effort.

Jan 1, 1968

By A. M. Gaudin

In the first place, let me thank you for inviting me to appear before you today to speak to you on "Mineral Industry Problems - Present and Future". It is a distinguished honor for me to have this opportunity, and I am highly appreciative of this distinction. The beautiful surroundings of Gatlinburg and the pleasantness of a summer occasion are a wonderful tonic for all of us, yet they should not blind us to the seriousness of our Industry's problems No doubt, because of my past appearances before members of the Society of Mining Engineers, at which I discussed wholly scientific topics, or research in the Applied Sciences, you may be expecting me to revert to these subjects. But I intend to venture in a field that is new to me, yet old to all of us, the field of Economics.

Jan 1, 1962

By Dale D. Teeters

Today, I would like to talk about ways to maximize the efficiency of surface coal operations. I doubt I will present any startling new ideas, but my comments may, hopefully, stimulate some conversation today and later back at your own operations. Strip mining is a very old technique used by ancient societies. Only with the coming of the machine age in the early twentieth century did we attempt to increase the magnitude of our operations. The industry, as we know it today, really only got started in the early 1900s with the advent of steam shovels. In the first portion of this presentation, I will attempt to show that we have, in many cases, not changed the basics of strip mining, only the scale. In doing so, quite often we have complicated the operations to the point of being unmanageable and unprofitable.

Jan 1, 1981

By Edgar Urbaez

Production scheduling is one of the most important factors affecting mine planning. A program -Mine Scheduler -that aids mining engineers with the setup of an optimum open pit production scheduling algorithm has been developed. A mathematical model for open pit scheduling that optimizes the Net Present Value of the cash flows was formulated. A simulated data is formulated as a Mixed Integer Linear Programming (MILP) problem. What's Best by Lindo Systems is used as the MILP solver in Microsoft Excel. The implementation of the algorithm focuses on problem setup, allowing users to easily evaluate, simplify, and develop the model that best fits their production scheduling.

Jan 1, 1999

By W. B. Weston

To mining people who have experienced the tremendous expansion of existing operations and the development of new properties over the last several years we do not have to point out the difficulties in hiring skilled equipment operators. To those of you who have opened operations in some of the more remote places in the world this is not just a difficulty. It is an impossibility. Your only recourse has been to try and train whatever manpower has been available. Depending upon your success in training, the next problem has been to keep them. On todays modern equipment, the skill of the operator remains as the greatest single variable affecting the performance of the machine. On a blast hole drill, for example, a skilled operator will get good production footage, acceptable bit life and minimal machine downtime The unskilled operator will not only fail to get the acceptable production footage but all too frequently this failure is coupled with low bit life, high repair costs and excessive machine downtime. Even between experienced operators, on identical machines, in the same kind of material we find significant variations in performance. It is, therefore, the skill of the operator, not just his experience, which makes the difference. The problem, as presented to us by our customers, has been to find a way for the unskilled man, with minimal training, to match the performance of the most skilled and experienced operator. The obvious answer is automation.

Jan 1, 1970

By George H. Davis

Much concern has been expressed recently as to whether water supplies will be sufficient to support accelerated energy development foreseen in operation Independence. Taking the Nation as a whole, sufficient water is available for energy growth, but locally, as in arid parts of the Colorado Basin, limited water supplies will dictate economies in water use and affect plant siting. As Young and Thompson1 point out with respect to electric power generation, the term "water requirements" is misleading, as demand for water for cooling is sensitive to price of water and thus is quite flexible rather than the inflexible or fixed level implied by the word "requirement." Much the same is true of other energy conversion systems. Water is used in many aspects of energy production including mining and reclamation of mined lands, on-site processing, transportation, refining, and conversion to other forms of energy. In the East, South, Midwest, and along the seacoasts, water supplies are generally adequate for energy industries; most water problems in those regions relate to pollution rather than supply. West of about the 100th meridian, however, runoff is generally less than potential diversions and energy industries must compete with alternative uses for the limited available water supplies. Water is especially short in areas of less than 10 inches mean annual rainfall where natural precipitation generally is insufficient for establishing vegetation without irrigation. Extraction. The principal categories of extraction comprise coal mining, oil and gas production, uranium mining, and oil shale mining.

Jan 1, 1974