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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 B. Cousins

Flotation reagents are critical to the optimum performance of flotation circuits. How a flotation reagent performs within the first few cells of a flotation train is a key indicator of how well it will perform throughout the entire circuit. A method to compare reagent performance was recently developed by Ashland Water Technologies. The procedure involves collecting a timed sample of concentrate from each cell and then measuring the volume of the settled solids. An estimate of the percentage of concentrate collected from each cell can then be mathematically determined, providing an understanding of the recovery changes in each cell. Data from trials at a coal flotation circuit are used to demonstrate the method's validity.

Feb 27, 2013

By H. Kempton

New methods for remediating metals-contaminated groundwater include in-situ emplacement of highly adsorptive substrates to permanently retard solutes. Substrates are introduced by sequential injection of soluble components that precipitate in the aquifer, forming a permanent high-retardation zone. This method overcomes the factors that limit pump-and-treat remediation; i.e, long-term source loading and slow desorption. Column tests demonstrated efficient substrate emplacement, increasing retardation coefficients of Cr(VI) by 20 and As(V) by 40. Similar effectiveness is expected for other heavy metals. Simulations using a coupled advective-geochemical model accurately matched substrate emplacement and arsenic attenuation, allowing extrapolation to other constituents and larger-scale applications.

Jan 1, 1999

By Rodney R. Krause

In attempting to tell the general public about the coal industry's land reclamation efforts, we have often said, "We're not doing things by the book, because we're still writing it." Like any good catchphrase, the statement is not only striking but true. It is particularly true in the mountains of Appalachia, where the problems of mining; and of reclamation are made more intense by the nature of the terrain. Mining and reclaiming the land "by the book' --which is to say by the methods of contour mining traditionally used in hill country--hasn't worked too well. So a lot of conscientious coal operators and associations are trying new methods--new ways of mining, new machines for seeding and planting, and new species to seed. Not all their experience can be transplanted to other areas, and of course I don't believe that Appalachia is the only place where new methods are being developed. Nevertheless, there's enough action in Appalachia to make a detailed examination rewarding, so let's focus on the hills to see what's new.

Jan 1, 1970

By Allen M. Newcome

The Ohio valley division of consolidation coal company has incorporated two new aspects within its coal mining concern. A new communication system, thru the cooperation of the c. & p. Telephone company, has been established in each of our mines with its central control in the general office building. In conjunction with this system, a Texas instruments 960 a computer has been incorporated into the system. The purpose for our computer is to provide modernization and improvement to our safety, production and maintenance programs. Thru proper use, the computer will help eliminate inaccuracies and inefficiences that have previously caused inaccurate analysis of problems. Due to federal requirements for more reliable communications in underground mines, Ohio valley division is making a concentrated effort to improve its communication systems. Systems such as the magneto phone and trolley phone have been looked at more critically. It was found that these systems are being used well beyond their limits. With these facts in mind, division personnel started looking for a system that would have these built in advantages: ease of maintenance and installation, increased reliability, low cost, and an inherent ability as a multiple use system.

Jan 1, 1975

By P. Johnson, G. E. Jones, G. K. Hoffman, C. B. Krueger, J. S. Raugust, M. Wilks, V. T. McLemore

The NMBGMR is slowly converting historical data into a relational database using Microsoft Access 97. The purpose of this database is to provide data on districts, mines, and mills in New Mexico to government agencies, public organizations, industry, and citizens to make informed decisions about resource development, resource management, water supplies, environmental impacts, hazard assessment, and waste disposal. Once the data are entered into the database with locations, the data can easily be converted to GIS format for displaying as different map layers.

Jan 1, 2003

By John R. Sturgul, Elizabeth Yost

The number of Native Americans presently working as mining engineers is extremely low-perhaps three in the entire US. At the New Mexico Institute of Mining and Technology, it was felt that introducing high ability students to mining engineering at the high school level would encourage more to consider mining engineering as a career. New Mexico Tech, in Socorro, NM, has initiated a continuing summer college program for Native American high school students. The program, which began in the summer of 1980, is designed to introduce participants to college life, enrich their high school curricula, and expose them to the problems and challenges of a career in mining and related engineering fields. Students From reservations throughout New Mexico with a demonstrated aptitude for science and mathematics were encouraged to apply for admission. Preference was given to high school sophomores and juniors since it is hoped that students will want to return for a second year before graduating from high school and beginning university studies. The program seeks to impress upon the students the need fir Native Americans in the fields of seience and mineral engineering.

Jan 7, 1981

By John B. Draper

The 1980 Mine Dewatering Act was enacted to protect water rights and to allow mine dewatering to proceed where impairment of a water right might have otherwise created a bar to mine development. In New Mexico, new appropriations for beneficial use are subject to the State Engineer's jurisdiction and are granted only upon a showing of non-impairment. Before 1980, mine dewatering was not considered a beneficial use, nor was it considered waste. The Act brings mine dewatering under the jurisdiction of the State Engineer, makes it subject to the same requirements as an application for appropriation for beneficial use, grants the right to replace the water of users whose rights would be impaired by mine dewatering without a plan of replacement, and extends the right of replacement to non-mining appropriations of water for beneficial use, Application of the Act requires determination of the definition of impairment (the threshold of significant impact on existing water rights), hydrologic evaluations to determine the impact of the proposed dewatering, and preparation and execution of a plan of replacement to avoid impairment of existing rights.

Jan 1, 1983

By M. J. McPherson, P. Mousset-Jones, G. Danko

Ventilation and refrigeration fortune climate modification contributes significantly to the operating costs of a deep hot mine. Mine climate simulation programs can he used to minimize the impact of these costs. There are several computer codes available to assist in this work. Whichever simulation program is used, it is the mine ventilation engineer who must supply the input data. This paper raises and answers the following question, namely, what accuracy is required of the basic input parameters, in order for a certain precision to he obtained in the predicted air temperatures? In the first part of the paper a new approach is described to estimate the dry and wet bulb temperature of the airflow, either in a dry or wet roadway. The calculation procedure allows an arbitrary temperature change with time, using Duhamel's superposition solution. Matrix-vector representation is applied to simplify the computational structure. In the second part of the paper the sensitivities of the dry and wet bulb air temperatures are analyzed, to the changes of the rock thernrophysical properties, the heat transfer coefficient, and the wetness factor.

Jan 1, 1987

By Joseph D. Drew

Oregon Resources Corp. (ORC) has developed and permitted a new mining operation that incorporates a process design that will allow the unique paleo-beach placer deposits of southwestern Oregon to be extracted efficiently and economically, creating the only domestically mined source of a unique foundry grade chromite and specialty de-veining sand for precision casting. The operation will also provide an additional domestic source of garnet and zircon. Engineering design has been guided by the variable geology and mineralogy of the paleo-beach placer deposits as well as the need for a dry tailing scheme that resolves a lack of water resources at the placer locations and at the same time eliminates the need for slurry settling ponds, typical of paleo-beach placer operations in North America.

Jan 1, 2010

By I. Duckworth

P.T. Freeport Indonesia operates a mining complex located in the highlands of Papua, Indonesia. This district consists of underground and surface operations. The East Ertsberg skarn system (EESS) is one of the major orebodies in this district. Subsurface caving of the EESS has been carried out in a systematic series of mining lifts dating back almost 30 years. Present production from the third lift deep ore zone (DOZ), has reached 80 kt/d (88,000 stpd) during 2010, with this rate sustained through 2015. The orebody was proven below the existing caving level, with the next vertical block called the deep mill level zone (DMLZ).

Jan 1, 2010

By Daniel H. McClain

A unique partnership between the Colorado Mine Safety and Training Program (CMSTP), the Colorado Rock Products Association (CRPA) and the Higher Education and Advanced Technology (HEAT)Center resulted in a video CD-ROM training program for new miners entering the aggregate industry. Cooperation from everyone involved, including the U.S. Mine Safety and Health Administration (MSHA),made this the product against which other training materials in the mining industry will be measured in the 21stcentury. This product’s versatility and wide application make it a tool that is as critical to a mine’s success as any earthmoving machine. The state and federal grant money involved allows this product to be affordable to small operators and independent contractors. The quality of this two CD-ROM set rivals any commercially made CD-ROM training.

Jan 1, 2003

By Steve Kral

The upswing in prices for base and precious metals, industrial minerals and coal has allowed the global mining industry to ramp up production at existing mines and begin construction of proposed projects. In addition to satisfying shareholders, the industry is also providing good paying jobs and creating needed infra-structure in places that previously did not have either. However, the industry has learned that the prospect of jobs and infrastructure is not necessarily a guarantee that communities will allow mines to be built. The industry must maintain even higher environmental and reclamation standards. And mining companies must help communities plan for life after a mine is closed and the company moves out.

Jan 1, 2005

By Leonel Lopez

Throughout Mexican history, mining has been an important, traditional activity. Before the "Discovery of America," native miners worked a variety of deposits throughout the country, including Mixtec gold and gem mines in Oaxaca State and Aztec gold, silver and copper from mines in Michoacán. The 500th anniversary of Mining in Mexico after the "Discovery of America" was initiated by the Mexican mining sector on April 15, 1991. As early as 1548, when the Guanajuato mining district was discovered, Mexico had become a leading world producer of precious metals. Since then, Mexican mineral production has developed in cycles, responding to changing technological, economic and political conditions. During the 20th century, Mexican mine output reached its peak in the decades of the 1930s and 1940s, when it was producing about 40% of the world's silver, 15% of its lead, 10% of its zinc, 4% of its copper and 3.5% of its gold. In 1990, by way of contrast, these percentages of world output stood at 13.5% for silver, 4.7% for lead, 4.1% for zinc, 3.2% for copper, and 0.43% for gold. The lowest production levels were recorded during the 1960s and 1970s, when Mexicanization of the industry and increasing state controls weakened mineral economics to a point that mineral exploration budgets were sharply reduced or eliminated, along with the industry's future. Only the noble old mining districts continued to supply production, with occasional eruptions of "bonanzas" and new extensions in established mining districts.

Jan 1, 1994

Despite the current economic downturn that is now decimating iron ore production, Minnesota?s mining operators remain optimistic about the long-term prospects for the industry. Reflecting this optimism, the development of several new mining projects continues in the state. The future of mining in Minnesota was the featured topic at the combined 82nd Annual Minnesota Section of SME Meeting and 70th Annual University of Minnesota Mining Symposium. More than 500 mining industry professionals, including engineers, executives, mining managers and equipment suppliers from the around the world, attended the meeting, which was held April 14 and 15, 2009, in Duluth, MN. The combined meeting featured a keynote session with three distinguished speakers plus a panel discussion by representatives from several of Minnesota?s taconite producers. The keynote speakers were Curtis Clark, president and chief operating officer, Behr Dolbear, who gave a presentation on the ?State of the Mining Industry.? Phil Newman, chief operating officer, CRU Strategies, spoke about challenges facing the mining industry and James A. Skurla, acting director, Bureau of Business and Economic Research, Labovitz School of Business and Economics, University of Minnesota Duluth, discussed the importance of mining to northeastern Minnesota?s economy. The taconite producers panel discussion included Jonathan Holmes, vice president and operations manager, ArcelorMittal; Ed Latendresse, vice president and general manger, Hibbing Taconite; John Tuomi, vice president operations services, United Taconite and Mike Mliner, vice president and general manager, Northshore Mining. The mangers provided updates on their respective operation The meeting included concurrent technical papers sessions on mining, processing, environmental and nonferrous mining. The sessions included technical papers that provided information on the status of a number of new mining projects in the state. The conference also offered a SME short course titled ?The basics of iron mining.? A tradeshow that featured about 100 companies and organizations offering products and services to Minnesota?s mining industry ran in conjunction to the conference. It was estimated that more than 900 people, including conference registrants and special invited guests of the vendors, attended the tradeshow opening reception. This was the largest trade show in many years. The Minnesota Section of SME also held its annual business meeting during the conference.

Jan 1, 2009

By M. A. Giralico

A new generation of hydraulic efficient pumper and auxiliary impeller designs is the result of an extensive research program focused on improving the overall performance of optimized SX/EW plants. Combined with the proper scale-up, these optimized designs will greatly reduce aqueous and organic entrainment losses, reduce or eliminate air entrainment and crud formation, enhance mass-transfer and maximize the overall copper yield. Currently, these new pumper and auxiliary impellers are installed full-scale in numerous plants ranging in flow rates from 90 to 15000 G.P.M. and developed heads up to 51 inches. Operational results reported by the independent metallurgist at each processing plant are reporting the lowest entrainment results in the industry. Further R&D has just been completed on a new mixing configuration that separates the systems mixing and pumping requirements. Results from the system pilot test document further improvements in reduction of both chemical entrainment and crud formation, while keeping mass transfer stage efficiencies.

Jan 1, 1998

By Kim Appleby

Epithermal gold-silver (lead-zinc-copper-manganese) mineralization on Misima Island is confined to steep and reactivated flat-lying normal faults in the upper plate of a major, shallowly dipping detachment fault. The hangingwall comprises an Eocene metavolcano-sedimentary sequence that has been extensively intruded byMiocene calc-alkaline granodiorite. It is unconformably overlain by Pliocene sedimentary and volcanic rocks. High-pressure amphibolite facies rocks dominate the footwall and have many characteristics of a metamorphic core complex. Mafic-alkalic lamprophyre dike swarms intrude the hangingwall and footwall sequences. Previous workers attributed the gold-silver mineralization on Misima to the intrusion of the porphyritic granodiorite (Williamson, 1984). This has been proposed for many tertiary gold deposits of the southwest Pacific(Sillitoe, 1989; Leach and Corbett, 1994).

Jan 1, 1996

By Duk-Won Park

A new gage for monitoring fractures in underground openings was successfully developed utilizing the reflection photo-elastic technique. The gage may be used to detect crack initiation in mine openings or tunnels so that remedial action may be taken to prevent further deterioration. Fringes concentrated around the cracks were spread by the use of rubber backing. Crack growth as little as 0.003 inch up to as much as 0.1 inch width were detected in this study. Variation of gage materials will provide alternative ranges. The feasibility of the method was tested and calibration was made in the laboratory study. Field study successfully demonstrated the capability of applications in detecting mine roof crack development.

Jan 1, 1982

The exploitation of the underground is currently undergoing a major transformation process. Besides mining, alternative ways of utilization are playing an increasingly important role. These alternative utilizations include the storage of gases, the disposal of radioactive wastes and the implementation of geothermal storage facilities. In addition, more and more mining operations are being shut down, like the German hard coal mining industry in 2018. But the integrity of closed mines must be ensured in the post-mining phase.

Jan 7, 2020

By Daniel H. Israel

Indian tribes own a substantial portion of the West's minerals. More importantly, Indian reservations contain coal, oil and gas, uranium, and oil shale reserves in unusually large and unencumbered blocks. Many tribes are now prepared to intensify development of their large reserves knowing that they can offer energy partners the unique opportunity to develop major energy facilities free of overlapping local, state, and federal permitting authorities. The tribes, therefore, can offer mineral developers both substantial reserves and an unusual degree of freedom from a multiplicity of government regulation. In the past, Indians and energy companies enjoyed only partial success as business partners. Indian tribes lacked the resources and know-how to act as equal partners with large oil and gas and mining operators. The tribes relied on the Bureau of Indian Affairs (BIA) to initiate and execute reservation energy projects, and as a result the tribes never developed adequate tribal structures and the expertise to responsibly manage their energy resources. At the same time industry made little effort to understand and learn the laws, customs, and institutions existing on Indian reservations. To the contrary, industry found it easier to bypass the tribes and deal with BIA officials. But the situation has changed. In 1975 the tribes organized an effective coalition, the Council of Energy Resources Tribes (CERT), which recently acquired substantial federal assistance to bring the tribes a level of technical and business expertise that begins to equal that of industry. Because the tribes have changed the rules of the game, industry must now change and learn to work directly with tribal governments. A working knowledge of Indian law, practices, customs, and policies must be acquired by energy companies before beginning negotiations with tribal governments for development of reservation energy resources.

Jan 6, 1980