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By CORA ROELOFS

In the USA, miners are at higher risk for work-related disorders that could precipitate an opioid prescription, injury-related opioid prescriptions, and opioid overdose. We aimed to support prevention of these outcomes with an “opioid hazard awareness” miner safety training module. In January and February 2020, the training module was embedded within required mining safety and health training for stone, sand, and gravel miners in Massachusetts (USA). Training impact and reception were assessed with a pre- and post-training survey of trainee characteristics, training content knowledge, and attitudes. Over 800 miners were trained and over 600 responded to surveys. We found statistically significant improvements in opioid risk factor knowledge and knowledge of resources to help a coworker. Nonstigmatizing attitudes were high both at baseline and following the training. The training was perceived as relevant and useful by trainees. Improving opioid hazard awareness in high-risk worker populations has potential to reduce opioid dependence and downstream impacts including overdose death. Employer injury-prevention efforts should be reinforced while worker health and safety training enhances awareness of opioid-related harms and prevention strategies for miners and other high-risk worker populations.

Nov 19, 2021

By William B. Schmidt

In July of 1974 a study team comprised of the authors was formed by the Department of the Interior. It was supported in part by funding from the National Science Foundation. The purpose of this study group was to visit coal mines and research and manufacturing facilities in England and Germany, to review the status of mining in these countries, and to identify mining technology which might have application to U. S. mining conditions. The duration of the visit was 18 days. The first week of the trip was spent in England. Time does not permit a complete recitation of the team's impressions but a few of the more interesting technologic developments will be discussed. These fall into the following categories- High Speed Development Ground Support Chainless Haulage and Face Conveyors Nucleonic Steering of Shearers Miscellaneous

Jan 1, 1975

By W. J. González

"With the increasing demand for minerals, technologies to maximize mineral recovery are paramount to a mine’s economic success. Many mining process waters have the potential to form calcium-based inorganic scales, which inhibit effective mineral recovery. Often, the solution to inhibit these deposits is the implementation of a chemical antiscalant program. This paper examines the application of a fouling analyzer to continuously monitor the formation of inorganic scale in mining process streams. The fouling data can be used to compare antiscalant programs and to optimize antiscalant feedrates. Case studies validate the ability of this technology to help optimize mineral recovery processes.INTRODUCTION The mining industry uses significant quantities of water. From quarrying, to crushing, to flotation, leaching, and refining, water is often the integral motive force to move slurries, separate or agglomerate fines, and extract and purify minerals. As well, water is used in a number of ancillary applications at mines, including dust suppression, gas scrubbing, and utility processes such as boiler, cooling, and waste water operations. For many processes, the quality of water being used is inconsequential. However, for certain processes, such as flotation, leaching, and desorption / stripping, water quality plays a key role in the ability of the operation to economically recover the target minerals. Dissolved solids such as calcium and magnesium salts can concentrate in process waters, exceed their solubility limits, and precipitate as scale on metal surfaces such as feed and transfer pumps, piping, and equipment. Some of the more common scales that form in mining operations include calcium carbonate (CaCO3, or calcite) and calcium sulfate (CaSO4, or gypsum), and to a lesser extent, calcium and magnesium silicate compounds. Any scale that deposits in a process stream will negatively impact mineral recovery, and increase the operational costs of the mine site. Whether it is acid washing a scaled heat exchanger in a carbon strip at a gold operation, replacing plugged emitter tubes in a leaching operation, or hydroblasting process lines in a scrubber unit, there are costs associated with labor, cleaning chemicals, repairs, and replacement parts. These costs pale in comparison to the potential costs of downtime and lost production, should the scale deposits occur in a process that is critical to the recovery of the target mineral."

Jan 1, 2014

By Dennis S. Kostick

Salt is a universal mineral commodity used by virtually every person in the world. Although a very common mineral today, at one time, it was considered as precious as gold in certain cultures. This study traces the material flow of salt from its origin through the postconsumer phase of usage. The final disposition of salt in the estimated 14,000 different uses, grouped into several macrocategories, is traced from the dispersive loss of salt into the environment to the ultimate disposal of salt-base products into the waste stream after consumption. The base year for this study is 1990, in which an estimated 196 million short tons of municipal solid waste was discarded by the U.S. population. Approximately three-fourths of domestic salt consumed is released to the environment and unrecovered while about one-fourth is discharged to landfills and incinerators as products derived from salt. Cumulative historical domestic production, trade, and consumption data have been compiled to illustrate the long-term trends within the U.S. salt industry and the cumulative contribution that highway deicing salt has had on the environment.

Jan 1, 1993

By W. W. Agey

The Bureau of Mines examined and tested the rhodonite deposits of the Silverton lead-zinc district, San Juan County, Colo., as a possible source of domestic manganese. Exploration and development work by several mining companies and preliminary reconnaissance of the area by Bureau of Mines engineers indicated the presence of extensive manganese resources in the form of rhodonite. This report summarizes the results of laboratory beneficiation tests made on samples of different type and grade material obtained from surface and underground exposures of seven veins in the district. Surface and underground examinations revealed the presence of several prominent veins that could be traced up to 2 miles for a single vein along the surface. The principal veins average about 50 feet in width and apparently carry rhodonite to considerable depth. Underground samples were taken from the Sunnyside, Silver Queen, Washington, Independence, and Scotia veins. Samples also were taken from surface exposures of the Sunnyside Extension and Hidden Treasure veins.

Jan 1, 1962

By H. Yilmaz

Tensile strength testing has been one of the most common physical property testing methods of thin spray-on liner (TSL) products worldwide. However, the variety of products tested has been insufficient for comparison purposes. Specimen preparation procedures and test parameters such as curing time and loading rate are not reported well. Comprehensive tensile strength testing on 20TSL products and one plain shotcrete brand was performed over 28days of curing period. Detailed information on the test procedures with particular attention on the important aspects during sample preparation and test execution are provided. As expected, the tensile strength increases with increasing curing period. The test results make the categorization and comparison of liner products possible.

Jan 1, 2010

Coal cleat and faulting influence failure, gas release, and choice of preferred mining directions, locations, and sequences. Unfortunately soil and younger rock cover restrict direct mapping of these structures ahead of mining operations. Aerial photographs of cover contain indirect indications of concealed structures in arrays of linear photostructures. These arrays are commonly too complex for interpretation by simple visual inspection.Analytical techniques applicable to complex arrays are illustrated for a covered part of the Galilee Coal Basin, Queensland. These techniques are: optical determination of sets in arrays of photostructures; correlation of these sets with sub-surface structures; filtering of m-rays for particular sets; detection of anomalies associated with concealed structures in the density distributions of particular sets; fitting filtered arrays to trajectories; correlation of trajectories with the regional directional variations of concealed structures; contouring of ratios of sets to discriminate anomalies associated with concealed fractures and variations in the total and bed thicknesses of cover; kinematic and dynamic inference on the basis of fracture-trace angular and spatial relationships.

Jan 1, 1979

By J. W. Eckerd

This report describes an investigation of the technical feasibility of using a conventional commercial-size (10-ft. i.d.), rotating grate, dry-ash-removal type gas producer to make producer gas from chestnut-size bone anthracite. Test instruments were installed, and some minor changes were made in the equipment to handle the large quantities of materials expected. Extensive tests, lasting about 4 weeks, were planned, using 35 to 50 percent ash chestnut anthracite bone. However, operations were suspended after 8 days when it became apparent that to use this type of fuel satisfactorily substantial changes in equipment and operating procedures would be required. Nevertheless, enough data were obtained to indicate that gas could be produced continuously and routinely from bone coal in this type of producer whenever conditions justified the necessary development work.

Jan 1, 1960

By Fernando Generoso Neiva Ferreira

O aumento crescente dos requisitos de segurança a serem atingidos pela indústria automotiva vem cada vez mais exigindo a utilização de aços com maior conteúdo tecnológico, que é o caso do aço bifásico (“dual-phase”), que são caracterizados por uma microestrutura ferrítico-martensítica. Neste trabalho, estudaram-se, em escala laboratorial, os efeitos das temperaturas de encharque intercríticas (750, 800 e 850°C) e distintas taxas obtidas por dois diferentes meios de resfriamento (ar e ar forçado) na obtenção de microestrutura bifásica a partir de dois aços laminados a frio “full-hard” (produzidos industrialmente), com micro-adições de Nb e Mo e diferentes teores de C e Mn. Utilizando ensaios mecânicos de tração, microscopia óptica (MO) e eletrônica de varredura (MEV), observaram-se as influências da temperatura de encharque e da taxa de resfriamento sobre as microestruturas resultantes e as influências da presença de ferrita encruada, dos carbonetos não dissolvidos e da morfologia da segunda fase sobre as propriedades mecânicas das amostras estudadas.

Aug 16, 2017

By Congling Shi, Marek Borowski, Yue Wang, Jianwei Cheng, Xixi Zhang, Xuan Xu

As the first barrier to prevent accidents caused by explosions in underground coal mines, the integrity and stability of mine seals have great effects on mine workers’ lives and underground production safety. In this paper, the mechanical responding performance of typical mine seals under the impact load are studied by using numerical simulation method. By such simulation studies, the safety of different seals subjected to the explosion load is evaluated. Seals’stability are also investigated under effects caused by various influence factors including thickness of mine seal, cutting depth into surrounding rocks, rock type, and the roof-tofloor convergence under given the explosion load. The research results can provide theoretical basis and reasonable improvements for mine seal’s construction practices for improving its anti-explosion performance.

By Congling Shi, Marek Borowski, Yue Wang, Jianwei Cheng, Xixi Zhang, Xuan Xu

As the first barrier to prevent accidents caused by explosions in underground coal mines, the integrity and stability of mine seals have great effects on mine workers’ lives and underground production safety. In this paper, the mechanical responding performance of typical mine seals under the impact load are studied by using numerical simulation method. By such simulation studies, the safety of different seals subjected to the explosion load is evaluated. Seals’stability are also investigated under effects caused by various influence factors including thickness of mine seal, cutting depth into surrounding rocks, rock type, and the roof-tofloor convergence under given the explosion load. The research results can provide theoretical basis and reasonable improvements for mine seal’s construction practices for improving its anti-explosion performance.

It is shown that factors associated with conditions whIch are thermodynamically favourable for the formation of CuS04 in roasting lead to high copper recoveries on leaching. One of these factors is the ratio of the air to solids used for roasting. This can be varied widely without loss of temperature control in the sulphating roasting of many Australian copper concentrates.Thus, the prediction of the air to solids ratio corresponding to a maximum p(SO3) value, for a given concentrate and temperature, is of importance in fluidized bed roasting, since this could be associated with the formation of a maximum quantity of CuS04. Calculations are presented which predict this air to solids ratio, not only for a given concentrate composition, temperature, and pressure, but also for air which is enriched with sulphur dioxide or oxygen.

Jan 1, 1968

The widely accepted concept of mineral resources are that they are finite - mining therefore being intrinsically unsustainable. Yet the modern global mining industry continues to grow production at strong rates - how can this be? In reality, mining is a complex industry, starting with exploration, development, operations and then rehabilitation and closure. A recent major study of Australia has shown that for most mineral commodities, exploration continues to find new deposits, or expand resources at existing mines. In parallel, however, there are a number of key 'mega-trends' which are growing in their importance - declining ore grades (or quality), increasing tailings and waste rock volumes, the need for deeper mining, more refractory ore types, increasing energy inputs and higher unit energy costs, increasing pollution issues and, of course, not to forget greenhouse gas emissions issues. This paper will present a detailed case study of the ultimate sustainability of the Australian mining industry - showing long term historical data sets on ore grades, waste volumes and economic resources and placing these trends in light of major twenty-first century issues such as energy supplies (especially Peak Oil), climate change and existing and emerging land use conflicts (eg agriculture versus mining). Australia is a critical case study in the sustainability of mining, as it is a major global exporter of numerous commodities, and this is expected to continue to underpin the ongoing industrialisation of countries such as China and India. The ultimate question begs - can Australia actually meet this fundamental challenge, or will our resources run out, or will we be constrained by environmental issues such as climate change, land use or perhaps water? Rather than a mere optimist's or pessimist's view, this paper will present a range of hard data which underpins the debate about the sustainability of mining this century: ultimately, we cannot assume that the patterns of past mining will continue to work in the future. The sustainability of mining continues to hang in a precarious balance.

Jun 1, 2010

By C. Rutledge

The new mining method of multiple strata blasting, called StratablastTM, is described in a separate paper presented at this conference. The current paper presents three case studies where the technique was implemented in three different configurations in large-scale blasts in Australia. The first two blasts were in the Hunter Valley of NSW while the third was at Ensham Mine in Central Queensland. All blasts comprised multiple layers that were blasted in a single drill and blast cycle, with unique designs applied to each layer to achieve different blast outcomes from the various layers.

Jan 1, 2006

The Australian Coal Combustion Testing and Research Facility has been operating commercially for one year and during that period coal product evaluations have been conducted on behalf of four coal companies and one electricity commission. The facility is equipped to assess the behaviour of steaming coal in milling, combustion (including flame stability, burnout and heat transfer), ash deposition and erosion, fly ash collection and gaseous emissions. The relevance of the results of the pilot testing to industrial practice was demonstrated during the calibration of the facility using four coals burnt in Australian power stations. The calibration coals were from the Tarong and Gladstone Power Stations in Queensland, tluja Power Station in Western Australia and Bayswater Power Station in New South Wales. Also an opportunity arose to visit an overseas power station to observe a full scale test burn using one of the early coals tested on a commercial basis in the combustion test facility. The calibration trials showed excellent agreement with industrial coal performance in t:orms of flame stability, turndown, carbon burnout and gaseous emissions. Encouraging correlations were also found in the case of furnace radiation, boiler deposits (slagging and fouling) and electrostatic precipitation. In the case of the last group the only real reservations about the correlations are due to the non-availability or qualitative nature of results collected around the power stations. In all cases there is a high degree of confidence in the facility's ability to predict the relative performance of different coals and in some cases direct numerical predictions can be Made.

Jan 1, 1987

J. H. Lord (Geological Survey of Western Australia): During the last few days in Kalgoorlie here we have heard on various occasions of the great job the mining engineers have done persisting against rising costs and increasing salaries without a rise in the price of gold. I think it has been somewhat overlooked that it has been difficult to find additional ore as well. I consider that geologists also should be commended on their action in persisting to search for more orebodies. This goes on in any mining community, but in Kalgoorlie in particular, I believe, over the last few years that it has been more difficult all the time to find additional orebodies and the Companies are calling for higher grades to offset the economic condition. I feel that this paper by Mr. Finucane shows that the geologists have persevered on an idea and discovered that they can find additional orebodies in the calc schist where previously it was thought that these did not occur. This has added many tons to the ore reserves, and although it is not very significant at the moment, the significance will probably improve as more work is done.The whole thing has shown us the importance of economic geology. Mr Finucane has had many years of experience here and he has given us a very able exposition of the economics of ore finding, and there are not many questions that one could pose to him, because most of the information he presented is obviously fact borne out by drilling, underground development and lining up the ore channels. He did briefly touch on ore shoots-the Oroya shoot and several others. It would be very good if we could, and I feel sure...

Jan 1, 1965

By H. R. Manouchehri

The importance of the grinding environment and its effect on sulphide minerals flotation behavior has been known for many years. The grinding environment may play a role in controlling fine and coarse particle flotation along with dissociation of different chemical species in grinding environment. Dissociation of different chemical species and ions within the process water may result from changing the grinding environment. The mining and mineral processing industry undertakes activities that may impact on water resources. These include use and storage of chemical storm-water management, process water management, mine dewatering and management of tailings. In mineral flotation understanding and controlling water quality is paramount important not only because of its effect on flotation but also with respect to control the quality of the water which is released to the environment. Releasing of different anionic and/or cationic chemical species in the process water results from the interactions among different mineral within the ore, process water, and the milling environment. In fact grinding mill acts as an electrochemical reactor which affects the flotation performances of different value minerals as well as the quality of the tailing products. An increasing in antimony content in process/discharge water at Boliden?s Tara processing plant in Ireland to above limitation level was reported in April 2010 which needed to be controlled. An increase up to 6 times of the permitted level was reported which needed an immediate action to control due to environmental considerations. Therefore attempts were made to detect why this higher amount of Sb is released and how to control and minimize its release to the process/reclaim water. This paper discusses how/why Sb content in process/reclaim water was increased by changing the mill electrochemistry and the strategies were taken into considerations to control it. Different strategies, including electrochemical controlling of the milling section, Fenton process, using Bauxsol in treating the process water, etc., have been considered and tested which are described herein. All strategies taken into consideration for solving the problem were successful which indicated good understanding of the issue and good decision making. Furthermore, for each solution the capital and operational costs were roughly estimated. Accordingly, the Sb content in process/discharge water was controlled to a value lower than allowed limitation, i.e., 1 ppm. Keywords: antimony, water contamination, mill electrochemistry, ag milling, grinding media, eh-ph, sulfide minerals, fenton process, bauxsol, lime addition

Sep 1, 2012

By T. J. Otto, G. C. Lindeque

Productivity is improved by increasing the ratio of output to input. In an operating open-pit mine, improving the productivity of heavy mining equipment (HME) enables the unit cost of production to be reduced. To optimize HME productivity, the Kolomela open-pit iron ore mine transitioned to an enhanced short-term mine planning (STMP) process that supports the application of a manufacturing-type operating model. At the core of the enhanced STMP process is a focus on integration across the open-pit mining value chain. The interdependencies between mining activities are highlighted and emphasized, thus ensuring that mining activities are synchronized. The improvements related to HME productivity were monitored from 2019 to 2020. The utilization of mining area in the Leeuwfontein pit improved from 71% to 90%, and the blasting frequency reduced by 14% while the average blast size increased by 17%. The distance travelled during shovel relocations between mining phases reduced by 16%, and the lost time associated with drills relocating reduced by 53%. These productivity improvements resulted in an 11% increase in the loading rate of the main waste shovel at Kolomela from 0.9 Mt/month in 2019 to 1.0 Mt/month in 2020. The enhanced STMP process can be adapted to other open-pit mining operations.

Nov 1, 2021

The following is a summary of some of the companies that were exhibiting their products and services at MINExpo INTERNATIONAL 2000. Atlas Copco develops, manufactures and markets rock drilling tools, tunneling and mining equipment, and surface and geotechnical drilling equipment. The company provides a line of drilling products, including production drilling rigs, rock reinforcement bolts and rock drills. Atlas Copco’s Boomer is a series of high-capacity drill rigs that provides economy, production capacity and reliability

Jan 1, 2000

By E. P. Youngman

The Siamese mining lew, which is cited as "The Sian Mining Act, 2461 (1919)," was enacted February 14, B. E. 2461 (A. D. 1919), corresponding to the ninth year of His Majesty's reign. This act replaces the Sian Mining Act of 1901 and repeals all edicts, decrees, laws, rules, and local customs relating to mining the terms of which are inconsistent with the new law. It shall in- clude all subsequent alterations or additions, as well as all rules issued by the Minister (of Land and Agriculture) already in force or to be brought into force publication in the Government Gazette to be deemed sufficient notice of any modifications or alterations. (Art. 1, 2, 5, 83, and 85.) Legislation passed recently amending certain provisions of the mining law for the purpose of controlling the sale of minerals is the mining amendment act, B. E. 2474, given August 21, 1931 (7th year of the present reign), which repeals provisions of the mining act, B. 3. 2461, and also all rules and regula- tions relating to mining that are inconsistent with the amending ect. Under article 25 of the mining amendment act, B. E. 2474, ministeriel regulations (of the Minister of Agriculture) were issued August 21, 1931. Further recent legislation, brought about by the agreement of the Siamese Government to become a party to the international tin restriction scheme (inter- national tin pool), is the tin and tin ore restriction act (Siam), B. E. 2474, which came into force on September 1, 1921, its purpose being to suspend the

Mar 1, 1933