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By D. L. Kuck

Water ice pillars far underground mine roof support can be frozen and/or maintained and/or melted on demand. The system to do this consists of a refrigeration brine chiller, brine circulation system and disposable plastic containers. Fusion expansion, resilience to dynamic loads, plastic deformation under stress, and non-contamination of coal or ore are unique properties of ice. Lower labor and material costs are economic advantages of ice far mine structural support. Ice brattices can become ice pillars on retreat. For safety, ice pillars can be placed (by remote control, if necessary) in hazardous sites without human entry.

Jan 1, 1988

By John Mastoris, Kostis Dragasakis, Kostas Kouklidis, Shkurtë Gashi, Halil Berisha, Jenuz Bulica

Titan Group’s environmental policy and Sharrcem’s Corporate Social Responsibility (CSR) are the driving forces behind the development and implementation of a comprehensive Rehabilitation Plan at Dimce Quarry, which is the main raw material source for Sharrcem Cement Plant since the 1970’s, located in the municipality of Hani i Elezit in Kosovo. Based on an Environmental Impact Assessment Study and the approved Mining Plan and also on the principles prescribed in the Guidelines on Quarry Rehabilitation, released by the Cement Sustainability Initiative of the World Business Council for Sustainable Development (WBCSD-CSI), Sharrcem has adopted a quarry operation and rehabilitation process in line with the best practices in the mining and cement sector. This paper discusses the background for the development of the rehabilitation plan and the results of rehabilitation activities, as have been implemented over the last few years. The main objective of the progressive rehabilitation plan at Dimce Quarry is to restore the depleted pit and return it back to the original land owners for resettlement. To date approx. 3,4Ha of former mining area has been restored by backfilling and levelling of the depleted closed pit and returned back to owners, who have built their houses and turned it into a living area again. This Quarry has turned out to be a real composition and practical example of preserving and returning back the natural resources in a state compatible with the surrounding environment and with respect to the needs of the local stakeholders. The motivation for business to engage in rehabilitation activities in the first place lies in the belief that the development and implementation of a progressive and practical Quarry rehabilitation plan and restitution of the land will deliver significant environmental and social benefits that outweigh the long-term rehabilitation costs, while maintaining the company’s reputation.

Jan 1, 2017

By Jaye Pickarts, Bret Boster, Jack McPartland

Pegasus Minera de Chile, Ltda. is completing three phases of metallurgical evaluation on the Pullalli project to develop a preliminary process flowsheet. A project feasibility study is in progress. The feasibility study includes a proposed process flowsheet designed based on results from the multiple stages of metallurgical evaluation. Phases I and II of metallurgical evaluation included laboratory scale heap leach and milling cyanidation testwork on multiple drill core composites and bulk ore samples from the Pullalli Project. Phase Ill included pilot scale milling/cyanidation testwork on Pullalli drill core composites. The proposed flowsheet includes selective mining and separate processing of low grade and high grade ores. Low grade ore will be crushed and heap leached. High grade ore will be milled leached for 12 hours in an agitated cyanidation circuit. After 12 hours of leaching, sands and slimes will be separated and the sands will be washed using a counter current cyclone (CCC) circuit. Partially leached and washed sands will be added to the crushed low grade ore for heap leaching treatment and permanent placement. Partially leached slimes will be thickened in a high capacity thickener and will be processed in a CIP circuit. Leached slimes will be placed in a tailings impoundment.

Jan 1, 1996

By Robert C. Peddicord

Application of Quality Management philosophies and techniques commonly referred to as Managing for Continuous Improvement, Team Management , or Managing for Consistency is required in today's mining, manufacturing, and service industries in order to meet quality demands, beat competition, lower costs, optimize operations, effectively use personnel, improve morale, and enhance profitability. Most of these phiosophies and techniques are known to today's managers but either have fallen into disuse or were never allowed to surface in the corporate environment of the organization. Managers should review and adopt the philosophies and techniques of Quality Management and use them to revitalize their organizations and bring about a "paradigm" shift in the way we manage, thereby achieving the goals listed above.

Jan 1, 1991

By Robert McEwen

Conveyor equipment beyond its prime chronically suffers from a lack of understanding in today's plant environment regularly delivers more material than original designers ever expected. A case in point is a belt conveyor in a major hard rock mine/milling operation asking to bring the unit up to current standards while eliminating spillage and reducing airborne dust. The challenge was to keep the system going by revamping the system while keeping the same footprint and allowing for higher production rate. Thirty years of daily maintenance and dust collection costs have virtually disappeared by the end of this challenging upgrade.

Jan 1, 2008

By W. G. Stevenson

The centennial celebration of the AIME provides an opportunity to review some aspects of developments in mineral exploration since 1871 and to reflect on the changes that have occurred. During this period seven Factors have fundamentally altered the procedures, techniques and philosophy of mineral exploration. Although most of these developed gradually, and unheralded, they have drastically altered the art of exploration and discovery. 1. ADVANCES IN MINING AND MILLING The development of huge shovels, draglines, trucks and track-mounted drills, to replace the wheelbarrow and single Jack has drastically expanded the rate of production for both underground and surface mining. The development of selective flotation has had a far-reaching affect on mineral exploration and has made it possible to extract metals from the metallurgically complex deposits discovered years before. These developments have reduced the costs of mining and treatment, and have transformed material into ore that was considered waste one hundred years ago. These advances have permitted exploration for progressively lower grade and larger mineral deposits.

Jan 1, 1971

By R. F. Hüttl

World-wide Germany is the leading lignite mining nation. Most of the lignite is produced in opencast operations. However, opencast mining causes enormous impacts on natural ecosystems and even on entire landscapes. The extensive production of lignite particularly in eastern Germany results in large devastated areas, which so far have been reclaimed only to some part. For the restoration of the post-mining area of more than 80,000 ha the major land use option is the reestablishment of forest ecosystems. However, adverse site conditions of the post-mining landscape such as extreme soil acidification and salt concentrations call for specific recultivation practices. Therefore, after the German reunification new reclamation and reforestation concepts have been developed for these brown coal areas of eastern Germany by the Collaborative Research Center (SFB 565) at the Brandenburg University of Technology at Cottbus (Germany). As a case study our comprehensive investigations into forest ecosystem development on terra nova in the Lusatian lignite mining district, south-east of Berlin, will be presented.

Jan 1, 2003

The implementation of NAFTA in January of 1994 was expected to have small but beneficial effects for the Mexican economy, mostly through increased investment flows. Mexico's mining industry was especially likely to benefit, as mineral investment funds would be diverted to the now safer Mexico and away from similarly endowed but more risky Latin American mineral economies. The results of the past two years have shown that it is governments and macroeconomic factors that influence investment flows, rather than the fine-tuning of trade flows through so called "free-trade" agreements.

Jan 1, 1996

By Murdoch Mackenzie

"Organic Polymers used as gangue depressants are classified according to their chemical structure. Absorption mechanisms for these reagents at the mineral - water interface are reviewed. The method of selecting these reagents for a particular flotation system is discussed. Details are given of methods of reagent solution make-up and distribution. Plant addition policy is reviewed.”

Jan 1, 1986

By G. R. S. Smith

In any filtration, it is primarily the filter medium (cloth) and cake filtering properties that control the type of filtration equipment used and filtration conditions. The advent of new types of filter cloths, such as the membrane cloth discussed in this paper, can result in significant changes in filtration techniques and areas of application for filtration. For many suspensions, for instance, conventional filtration is uneconomic compared to gravity separation or not filtering at all (as with product recovery from dilute streams) because the solids are very fine, are hard to retain and build up filter pressure rapidly, and once retained are hard to remove. As a result of the developments discussed here, this is no longer the case. This technique and the use of the membrane filter cloth is well established. This filtration is currently being used for white liquor filtration in twenty-four mills worldwide in the chemical recovery step of the kraft process for producing paper pulp where it is replacing gravity thickeners in new plants. Filters up to 1000 sq. ft. (100 sq. meters) are filtering large volumes of solids from hot caustic solutions. The filtration materials and techniques discussed in this paper open the way to new methods and applications for filtration in the mining industry. It is not the intention of this paper to give a vigorous analysis of the different separations, but to outline some of the ways in which this filtration technique might be used in the mining industry.

Jan 1, 1989

By M. J. Shields

There are numerous suggestions in the literature on methods of obtaining representative samples of waste rock or mill tailings. Some suggested methods would result in thousands of samples and very high costs for a large facility. There is no general rule that can (or should) be followed, such as collection of a given number of samples per mass of material, per acre of impoundment, or per foot of drillcore. Each site is different, and the adequacy of sampling must be tailored to the site. A logical approach is to let the variability at the site dictate the number of samples that should be collected and analyzed, and then to quantify and evaluate the results by means of standard statistical methods.

Jan 1, 1998

By Bruce Watzman

Can the United States mining industry achieve its long-stated goal of zero fatalities ? and what will it take to do so? Does it require new laws and regulations, as some propose, and a continuation of the commandand- control model that has been born out of more than 40 years of regulation and enforcement under the Federal Mine Safety and Health Act of 1969? Or, is it time to consider a new model to manage safety and health and drive continuous, sustained improvement? These are questions that many are debating as mine safety performance, while improved, appears mired in a trough where improvement followed by declines seems to have become the rule rather than the exception. Without doubt, U.S. mines have made significant progress in safety performance during the last four decades, yet the stalled decline in fatality numbers, the industry?s report card of its success or failure, has led some to question whether the industry will achieve zero fatalities in U.S. mining by relying solely on the Mine Act?s framework and implementing its regulations. These are questions the CEO-led task force, set up by the National Mining Association (NMA), considered as it sought to identify impediments to zero fatalities posed by the current regulatory regime. Out of that effort came CORESafety, a common safety and health framework that relies on a management system approach to improve safety and health performance. The goal of CORESafety is to achieve zero fatalities and a 50-percent reduction in the rate of injuries in U.S. mining within five years ? 0:50:5. CORESafety is built on the plan-do-checkact model, which has been successfully deployed by industries, mining and nonmining alike, to drive continuous improvement in safety and health performance. The improvements in safety performance that can be achieved by shifting from a command-and-control regulatory approach to a risk-based systems approach built on the plando- check-act model have been documented in numerous industries. For example, the United Kingdom quarrying industry (Fig. 1), not satisfied with the number of reportable accidents being experienced 1995-2000, established a hard target of a 50-percent reduction in the number of reportable accidents during the period 2001- 2005. Having met this target, the industry then established a further target zero for the period 2006-2010. The mechanism to achieve these reductions? The plan-do-check-act model.

Jan 1, 2014

By W. M. Haffner, S. L. Borek, H. M. Edenborn, R. W. Hammack, D. H. Dvorak

The conceptual designs of three new applications for the biogenic &S treatment of metal- containing waters are presented. These include: 1. the treatment of a circumneutral-pH ground water containing Zn and Cd using limestone as an alkalinity source, 2. a two-step treatment process where toxic heavy metals in contaminated ground water are recovered separately from nontoxic metals to lessen disposal costs, and 3. a copper recovery process that may be a low-cost alternative to solvent extraction/electrowinning or cementation for dilute copper leach liquors. Preliminary results of initial field testing are discussed

Jan 1, 1995

By Sylvain Duchesne, Claude Bazin, Robert Grant

Grinding simulators are now widely available to assist in the selection of circuit operating conditions or flowsheet designs that yield a given product size distribution. These simulators do not inform of the impact of the grinding product size distribution on subsequent flotation stages. This paper presents a method to predict the effect of fineness of grind on a flotation bank operation. Application of the method is illustrated with data from two Canadian concentrators.

Jan 1, 1995

By Hayward B. Oblad, Anthony G. Fonseca

Coal flotation has been practiced since about 1920 in Europe and since about 1926 in the U.S. Over 200 U.S. coal preparation plants now use the process to recover coal. Over the 60 year period, the fundamental principles upon which flotation is based have been enumerated, but the interaction between the parameters that affect flotation has not been quantified and a useful model which accounts for these parameters has not yet been developed. A comprehensive and user friendly kinetic model coupled with better process monitoring and control instrumentation would allow plant operating personnel to better predict flotation performance and better control the flotation process in coal preparation plants.

Jan 1, 1989

By James A. Clem

Approximately 2,000 years ago, the Lord Admonished the Scribes (Lawyers) and Pharisees (Religious leaders of that time) that they had paid the tithe but had omitted the weightier matters of law, Judgement, Mercy, and Faith. (Matt. 23:23). I want to talk about "The Weightier Matters of Law." In a situation where big government is trying to have an effect on even small details of a work activity, otherwise simple situations become complex. Regulations are written to such detail that constant compliance with strict interpretations can be a nightmare--not to mention off the target of the intended purpose for the regulation. One soon re- cognizes the oneros characteristics of Federal statues

Jan 1, 1979

By P. G. Irwin

Natural resins, those derived from coal and those mined in the Uintah basin, face challenges from synthetic resins that are derived from petroleum sources and rosin or wood sources. In the past, fossil resins from coal were produced by various companies, the last one being Hercules, Inc., which sold BLACKHAWK resin until a fire destroyed the plant in the mid 1970's. Approximately four to fjve million pounds of BLACKHAWK were produced and sold mostly to the printing ink industry. Uintaite, more commonly known as Gilsonite® resin, was widely used by various industries, notably in printing inks, coatings, stains, adhesives, foundry, asphalt paving, and oil well drilling muds. Gilsonite has lost market share over the last thirty years to various synthetic resins particularly hydrocarbon resins that are derived from petroleum sources.

Jan 1, 1990

By W. Robert Power

Dimension stone includes a wide variety of natural materials that are put to an equally wide variety of uses. It is possible to classify dimension stone according to the end use to which the stone is put or according to the lithology of the stone. Both schemes are used by the United States Bureau of Mines in the annual Minerals Yearbook. The 1969 Yearbook lists 15 specific uses and has additional miscellaneous catagories. The same Yearbook lists five specific rock types or lithologies, and also includes a miscellaneous category. In a short presentation it would hardly be possible to list and define all these categories, much less discuss the evaluation of deposits with regard to all possible combinations. Besides, I am only slightly familiar with some of the uses and their requirements. I have therefore chosen to limit my remarks to some special problems in evaluating dimension stone that is to be cut and finished to specific sizes, tolerances, and finishes for use in buildings and some monuments. This use class is called cut stone in the Minerals Yearbook. In terms of dollar value it is the largest single use category. In 1969 the dollar value of cut stone was $29,122,000 which is more than twice the value of the next largest category. For those of you who are interested in other use applications of dimension stone I suggest that you start with recent articles by Bowles (1960), Currier (1960), and Barton (1968).

Jan 1, 1972

By J. E. Bevan

Once mining compromises the stability of a rock mass, the dangerous task of roof bolting begins. Many attempts have been made to automate this process, but there are still many refinements that need to be made. In the past, roof bolting modules were designed around the abilities of a human operator. Currently, researchers are taking a new approach that focuses on designing modules that can utilize bolting methods that are easily automated. A non-rotating anchor that is locked into position by a linear force (as opposed to a rotational force) was designed by researchers at the U.S. Bureau of Mines. Once the bolt is secured in the bolt-hole by the anchor, the bolt is tensioned and a collet is used to secure the other end of the bolt. This process replaces the traditional bolt-nut fastening method. This program is part of an effort at the U.S. Bureau of Mines to automate the coal mining process.

Jan 1, 1994

By R. R. Tatiya

This paper describes the local estimation of mineral inventory by kriging. A mineral deposit located between two working levels of a copper mine was examined. Data for this estimation was obtained by underground diamond drilling. The mineral inventory that was computed by this method was compared to the results obtained by global estimation techniques, which were based on information front surface boreholes. A comparison between the ore reserves estimated through kriging and the ore reserves estimated at the mine using conventional methods was also made. This analysis shows that geostatistical methods can be applied to evaluate base-metal deposits similar to the deposit examined in this study. In the part of the mine that was examined, the kriging estimates show an overall increase in metal content at all cutoff grades, compared to the estimates obtained through conventional methods. Also, the ore body profiles are more continuous and regular through kriging, but they are not radically different from the profiles that were previously obtained at the mine. However, the global estimate of the deposit using kriging could not provide reliable results.

Jan 1, 1997