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By Z. Kowalski

Landfilling of waste causes the degradation of natural environment, not only due to land occupation, but also due to pollution of air, water and soil. The flotation waste from zinc-lead industry also poses such problem. There is a need to find the way to utilise substantial amount of these wastes and backfilling seems to be a good solution. Recently, in Poland only sand was used for backfilling. However, it will be more beneficial to substitute the sand with the industrial solid waste, especially flotation waste. The tests were performed in the laboratory to examine the use of flotation waste as a main ingredient for backfilling. The use of flotation waste is possible only when it is combined with other waste with specific bonding properties, especially regarding the prevention of leakage. The outcome of tests shows that flotation waste combined with cement and fly ashes can be used as a backfilling material. This paper presents the preparation of flotation waste for using it for backfilling.

Jan 1, 2006

By Julian Brown, Steve Hicks, Zach Agioutantis, Zachary Wedding

Analysis of Coal Pillar Stability (ACPS) software, released in 2018, integrates numerous empirical pillar design techniques. The ACPS program incorporates methodologies originally available as design tools from the National Institute for Occupational Safety & Health (NIOSH), including Analysis of Longwall Pillar Stability (ALPS), Analysis of Retreat Mining Pillar Stability (ARMPS), Analysis of Multiple Seam Stability (AMSS), and concepts including Coal Mine Roof Rating (CMRR), the Mark-Bieniawski pillar formula, and pressure arch loading. The design methodologies that are the basis of ACPS were developed via analysis of significant amounts of real-world data and have been standards of the United States coal industry for decades. While there are empirical factors built into ACPS, making it ideal for use in U.S. coalfields, the concepts in the program have proven to be applicable in variable mine settings, and the software was developed to allow for user-based, site-specific modifications of key design inputs. Application of ACPS to cases outside the regions for which it was developed must be approached carefully, and continuous development of site-specific data is mandatory. A case study is presented involving the application of ACPS to assess pillar stability and assist future design for an underground lignite mine in Eastern Europe. Assessment of in-mine observations, review of the geology of the lignite mine, and evaluation of specific conditions associated with a failure event resulted in “calibration” of key input factors to ACPS. Scenarios evaluated with ACPS suggest that pillar strength and overburden depth are key factors for the determination of pillar stability and design in future areas.

Jun 25, 2024

By B. E. Zeigler

This bi-product from a nickel smelter has been manufactured over the last 30 years for the abrasive and roofing industries. This paper discusses a new development for this material a foundry aggregate used for molding sand in both ferrous and non ferrous casting industries. Test data, marketing strategies, manufacturing, and case studies will be presented from the first concept, to current production, marketing and the end use of this product.

Jan 1, 1999

By Leslie S. Rubin, John C. Roberge, Mackenzie Burnett

A self regulating helical inducer has been developed and tested for dry injection of coarse or fine solids into a hydraulic pipeline. This centrifugal pumping device has also been modified and tested for use as a boost pump in medium and long distance pipeline haulage systems. The helical inducer has been operated as an integral component of a slurry injection vehicle. This compact, low profile vehicle also includes crushing and screening components, solids feeding components, a track drive system for mobility and is run by a single operator. The helical injector and boost pump operate without speed and flow controls allowing for the practical hydraulic transport of excavated materials.

Jan 1, 1983

By S. B. Leonov, K. I. Popov, S. B. Polonsky

The offered technological line includes a flotation pulp air conditioner operating on the impact-mechanical effect and two column apparatuses with a descending pulp-air flow mounted in series. The technology developed makes it possible to increase considerably the valuable component in the concentrate simultaneously with a reduction in energy consumption for the flotation process. The experience achieved with the technology showed the possibility for obtaining sulphide silver-bearing ore superconcentrates with the noble metal content 2-10 times higher than that in the concentrates obtained by the conventional technology. The same results were obtained in the process of calcium-bearing boron-silicate ore-dressing.

Jan 1, 1995

By Fabio Mielli

The mining industry is a multifaceted industry with special characteristics that make efficient and intelligent operations uniquely challenging, and subsequently call for distinctive and tailored solutions. Not only does mining call for processes that are complicated and energy intensive, but complex material movements and an intricate logistical chain add to the industry?s obstacles in achieving sustainability and performance. This article explores three major challenges and the resulting issues currently being faced in the industry, as well as potential solutions to these impediments by use of energy management, automation and control strategies.

Jan 1, 2011

By D. C. Torre

The coal mining industry has long recognized the need for a system capable of hauling mined coal from the face in a continuous flow. More than 30 years ago, successfully operating continuous haulage systems were first placed in the field. There were a few individually successful applications. However, the truly successful use of such systems really only began in the early seventies. Today, a variety of systems are available from a number of manufacturers. Even so, continuous haulage has not achieved the acceptance and application it would seem to have earned. There is a need for more productive, cost-effective, and safer methods of hauling coal from the face. There is also a need to speed up development for longwall operations. And continuous mining is not really "continuous" unless it is supported by a reliable continuous haulage system. Despite all this, most of the coal producers have failed to exploit the successful continuous haulage systems offered by several manufacturers. In the 1970s, many of the top coal producers tried a continuous haulage system but gave up on it and on the concept. In some cases, major coal companies had systems operating successfully in one mine, or even one division. But their use did not spread to others of their mines or divisions. Frequently, their use was eventually abandoned, even in mines where it had been successful.

Jan 1, 1990

By Frank T. Wheby, Edward M. Cikanek

A computer performs all logic and computations customarily done by hand in preparation of engineers' estimates or contractors' bids on tunnel-shaft systems. The program described is based on construction methods, work forces and equipment selections corresponding to the current state-of-the-art of rock, soft ground and cut-and-cover tunneling. The program contains logic to permit estimates of cost of complicated tunnel-shaft systems; it is not necessary to input quantities, as the program calculates those from the tunnel design that is internally generated. In any estimate, the program bases its cost computation on user-input requirements and site conditions, such as tunnel shape and size, shaft depth, ground characteristics, construction methods, and other factors. To provide great flexibility, the user of the program is provided with options for accepting designs built into the program or overriding these designs by his own inputs. An illustrative example is presented.

Jan 1, 1974

By J. Loredo

In some rural regions of Peru, artisanal gold mining is currently an essential activity as it provides an important source of income. In the Huanca region (Ayacucho Department) gold deposits are not attractive for mining companies due to their reduced size, but they have enough interest for artisanal mining because of the ease and low cost of mining operations. Artisanal gold mining represents an important damage for the environment, because operations related to amalgamation processes using Hg result in special environmental problems besides the typical ones commonly associated to all mining activities. A preliminary sampling has been made in soils, materials from tailing ponds and surface water of the Acarí River, at the site of the Huanca village, according to networks specially designed for the particular conditions of the area. Studies accomplished revealed high mercury concentrations in soils and tailings. Chemical analyses of soils directly collected in the area of the active or abandoned ?quimbaletes? show mercury concentrations ranging from 15.3 mg?kg-1 to 44.2 mg.kg-1. Mercury concentrations in soils decrease as a function of distance from the before mentioned sources. Water quality of the Acarí River that flows through the area does not present important changes as a consequence of the mining and processing operations.

Jan 1, 2006

By E. M. Frizzell

This paper addresses the use of the microcomputer programs BACKONE and BACKWEDG for an estimation of rock mass strength characteristics by back analysis of plane and wedge failures. The artificial support requirements are also determined by the programs PLANE2, BOLTPAT, and BOLTWEDG in terms of rock anchor installation angles, tensions, and installation patterns. These programs have been combined into a package called BACKPACK, which can be applied in open pit mines where some failures have already occurred.

Jan 1, 1988

By C. Roos

Traditionally within the mining industry, the main functional process flow for resource and reserve evaluation proceeds from geologists who build the geological model, to resource estimation geologists (modelers) who estimate the grades, to mining engineers who develop the mine design and schedule. The interface between these three disciplines is not always seamless. Assumptions made during one stage of the process are not always communicated down the line, even though most mining companies have procedures in place to encourage communication across the various disciplines. These procedures do not always achieve their aim due to a variety of reasons including time constraints, appropriate people not being available, or a lack of understanding of what other disciplines require, and the handover process can degenerate into one of sending computer files on to the next discipline in the process flow. This paper focuses on the interface between the resource estimation and mine engineering disciplines, and outlines some of the common assumptions made when generating a resource model and the risks that engineers may be taking when elevating cutoff grades, optimizing schedules or generating forecasts. The case studies presented focus on openpit gold deposits, but the concepts should be applicable throughout the industry. A summary of key questions and recommendations is provided.

Jan 1, 2014

By T. Kretschmer, F. Villwock

Conveyor systems are an essential part of many material movements in all conceivable areas of application. They are used to transport goods in raw materials extraction, agriculture, and even articles for daily use. In the process, not only distances of several kilometers but also differences in altitude of several hundred meters are bridged. The layout of the conveyor usually follows the topography at the respective installation site. Particularly in the case of large height differences, safety devices must be provided to prevent uncontrolled movement. Backstops can take over this task in predominantly ascending overland conveyors and are used either as a primary or as a secondary safety system in conjunction with a service brake. They are always used when the system comes to an unplanned standstill, whether due to a power failure, an emergency stop or a defect. When designing backstops, it must be ensured in any case that all conceivable circumstances are taken into account so that failure is ruled out without the product being unnecessarily large in size. Various safety factors are applied, some of which are even prescribed by authorities. One example is the Australian standard on machine safety for bulk material belt conveyors (AS/NZS 4024). This stipulates a redundant acceleration safety device that can absorb at least 150% of the maximum load. ALTRA Industrial Motion with its sister companies Marland and Stieber manufacture backstops for a wide range of applications. With more than 85 years of business activity in freewheeling and backstop applications, they are among the most known and experienced companies and provide a great know-how.

Mar 2, 2022

By John Wiebmer

Several industry trends are putting new demands on surface mining equipment. This is true both on the “hard” side of the equipment business - the research and product development programs, and on the “soft” side - the business processes, human resources and competitive strategies. This article describes seven key industry trends and the impact each is having on surface mining equipment suppliers. 1. Globalization Earth-spanning technologies are shrinking the world into an economic village, causing corporations to think and plan on a global scale. This “globalization” is one of the great buzzwords of the 1990s, meaning precisely whatever the user says it means. In this case, let us take it to mean that political boundaries arc less restrictive than in the past, permitting mining companies new freedom to roam the globe for ore bodies. Evolving out of this are global mining houses that have ownership and management interests in labyrinthian webs of mines spanning the world. There are several impacts on surface mining equipment suppliers.

Jan 1, 1994

By Jack E. Thompson

Thank you Tom and JM for that nice introduction. The remarks I am about to make rely on a large way on comments made by Barrick's Chief Counsel, Patrick Garver, to an internal meeting of Barrick's senior staff. I plagiarized so much from his notes that I thought that I should provide attribution. I did get his consent to borrow so freely. What I have done is take his general comments and used my conversations with CEO's and other participants in the industry to enhance the message with concrete examples that underscore the points I wish to make. What you are about to hear is my personal view – I am not speaking as a representative of any company. With that introduction, now would be a good time to give you the main theme of my talk: The SEC should change its rule making to a more public cooperative approach. If that were to happen the SEC would avoid some of the harm it has been doing to the companies in this sector and the very shareholders it seeks to protect.

Jan 1, 2003

By Robert R. Munro

Introduction Traditional aggregate sources - riverbeds and alluvial fans - located close to developing urban centers are being foreclosed to mining. As sand and gravel reserves are depleted, nearby production plants cannot secure additional, adjacent reserves and are being forced to close down. The sand and gravel industry, in many respects, is its own worst enemy. It promotes development, street paving, home building, and industrial and commercial centers. Economics make us favor developments close to our operations. Thus, we encourage development by our neighbors, who soon become our detractors. Current Aggregate Mining Problems Urban development is not compatible with sand and gravel mining. Neighbors dislike the view of pits and quarries, and they complain about dust, noise, and trucking. In general, the neighbors are not happy being close to an aggregate source. This is reflected in land use or zoning laws. In most localities, mining requires a special-use permit. Public hearings are required before a legislative body. If a large group of opponents show up, legislators will often deny the land use. Urban areas are seeing traditional close-in sand and gravel sites becoming no longer available for industry. A parallel situation is also developing in most urban areas. That is, the not-in-my-backyard attitude toward landfills. As urban areas mature; a significant amount of change takes place in the physical makeup of a city. Streets and parking lots deteriorate and need repaving. Curbs and gutters need to be relocated. This necessitates a place to dispose of excess, or old, paving and structural material. Since landfills have become at least as difficult to permit as sand and gravel sites, they are becoming remote from urban areas. A significant portion of the structural material that needs to be disposed of is concrete and asphalt. This material is heavier than other materials. Thus, the cost of moving a large volume of very heavy material to a landfill becomes very expensive. In California, dump truck transportation is regulated by the State Public Utilities Commission through minimum rate tariffs. A rule of thumb for estimating the cost of such transportation is once the material is loaded, the extra kilometer (mile) costs $0.09/t ($0.08 per st). Thus, to haul an 18-t (20-st) road an extra 32 km (20 miles) will cost about $32. Because of its remote location, the cost of hauling aggregates to the point of use in an urban area becomes excessive - about the same as hauling the material to a landfill. Here is a classic example for synergism. If we could save the transportation cost of heavy demolition material by disposing it relatively close to the central city (its source), and at the same time provide an aggregate source close to the central city (its point of use), two difficult economic situations can be solved. Thus, the develop¬ment of recycling concrete and asphalt. Mining Concrete and Asphalt There are two methods of mining concrete and asphalt. The first is to pick up the old pavement in pieces. Thin, cracked pavement can usually be lifted from the grade with a front-end loader. It will break up into manageable-sized pieces. With heavier pavement, it is sometimes necessary to intentionally break it up with a stomper or heavy ripper. The pieces are loaded into heavy dump trucks and shipped to the crushing site. Again, a front-end

Jan 7, 1984

By P. C. Clark

This paper is an overview of the requirements and concerns for minerals and pigments used in papermaking. The first part of this paper deals with mineral or pigment filling in the actual papermaking process. The second part deals with the pigment or mineral properties that are important in today's coating processes.

Jan 1, 1993

By William M. Hartzler

The Powder River Basin (PRB) refers to the coal deposits located in southeastern Montana and the northeastern Wyoming counties of Campbell, Converse, Hot Springs and Sheridian (Wyoming PRB). In 1993, there were 20 active surface mines with 3109 employees in the Wyoming PRB (Annual Report, The State Inspector Of Mines Of Wyoming, 1993). Early PRB production growth was primarily in response to the passage of the Clean Air Act of 1970. The disproportionate growth in Wyoming as compared to Montana can be attributed to the differing coal taxation policies of the two states. The state severance and production taxes were significantly lower in Wyoming. However, Montana passed legislation in 1987 reducing the severance tax rate, substantially narrowing the severance tax gap. Campbell and Converse counties in Wyoming have benefited the most from the production growth in the region. Cyprus Amax's Belle Ayr Mine, south of Gillette, in Campbell County, was the first modern commercial coal mine to be developed.

Jan 1, 1994

By R. E. Vivas

Goldcorp is one of the largest gold producers in the world with projects in South, Central and North America. Goldcorp?s flagship operation is Peñasquito, a world-class, poly-metallic deposit that started production in 2010 which is one of the largest mines in Mexico. Since the early stages of the project, Goldcorp has used the most advanced technologies available to maximize its value. However, the implementation of optimum mine plans has been challenging to put into practice. This is due to the fact that the mine operation involves more complexity than the plans usually reflect. This challenge is an industry wide issue that presents opportunities for improvement. This technical session discusses the mine planning methodologies and procedures used to connect long, medium and short term planning strategies in order to bridge the gap and produce optimum mine plans that can be practically implemented in the field.

Feb 23, 2014

In 1991, environmental issues related to coal mining continued to be an integral part of managing a cost-effective operation. Environmental regulations and their implementation can create considerable cost burdens on operating mines. Environmental responsibilities require management decisions to be made on a whole systems approach that is comprehensive in costs and consequences. Most of the regulatory activity in 1991 that affected coal was related to reauthorization or revision of several pieces of legislation. Issues related to the reauthorization of the Clean Water Act, the Resource Recovery and Conservation Act (RCRA) and Abandoned Mine Land. Clear Water Act considerations will encompass discharge standards, wetlands issues and proposals to regulate ground water quality at the federal level. Discussion regarding RCRA includes efforts to expand regulatory authority into the area of coal mine waste. That is currently regulated by the Office of Surface Mining (OSM). Another RCRA consideration will be the disposal of coal combustion byproducts. Abandoned Mine Land reauthorization continues the Abandoned Mine Land tax on coal operators. This tax has been in effect since 1977. Regulatory revisions were also proposed by the Department of Interior on valid existing rights, subsidence, federal coal leasing programs and OSM's troubled Applicant Violator System. Industry officials have been critical of the revisions. A federal appeals court found that evidence supported claims by Whitney Benefits, Inc. that the passage of the Surface Mining Control and Reclamation Act (SMCRA) deprived the owner of full economic use of its property. Before SMCRA's passage, Whitney established an operating agreement with Peter Kiewit Sons Co. to mine coal.

Jan 1, 1992

By Jerry L. Purswell

INTRODUCTION The principal OSHA standards dealing with tunneling activities are found in 29 CFR Part 1926. A reference for the applicable subparts which apply to tunneling is included as Appendix A. In addition, some standards from 29 CFR Part 1910 have been identified as applicable to construction and are included in the recent printing of an interim vertical standard for construction (1910/1926 Project). The remainder of this presentation will be focused on past OSHA activities to revise Subpart S of 1926, the principal subpart dealing with tunnel construction.

Jan 1, 1979