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By Douglas Castleberry

The degree of fragmentation obtained in primary quarry blasting has always been a factor in the speed of digging' the muckpile This paper will discuss a case history of increased production and associated lowered costs from increased fragmentation. The quarry under discussion is fairly new, located in Georgia, and is in the large operation .category. Loading is done by three yard shovels, and, primary crushing by a 48" x 60" haw crusher preceded by a 5' wide feeder. The stone is a hard granite gneiss, of Los Angeles rating 22, and apparent specific gravity is 2.68. The product is shipped to points in that state for railroad ballast, concrete aggregate, and road building stone. Inasmuch as fairly large shovels and a large Jaw were to be utilized, initial drilling and blasting were pointed toward producing fairly large sized muck for this large equipment. This was following a concept somewhat in vogue for some years in the Southeast wherein many large equipment plants would tend towards larger fragmentation, and smaller equipped plants would conversely tend toward attempts at smaller sized rock piles for smaller shovels and crushers.

Jan 1, 1960

By Jorgen Elbrond

In a stream of ore in an underground mine or in a beneficiation plant bins are installed between machines or machine system. When the upstream machine is stopped the downstream machine can continue operation for a while and vice versa. The paper describes a procedure for calculating the total capacity of a system consisting of two machines with an intermediary bin as a function of the bin's live volume and of the installed machine capacities and their production variations, which are defined. Extensions to several machines in parallel and in series are shown as well as practical examples.

Jan 1, 1982

By Paul D. Tomlingson

Numerous worthwhile benefits accrue to the industrial organization that is supported by a maintenance organization performing at a world class level. That organization will be favored with consistently reliable production equipment. It will be assured of meeting production goals. Its product will exceed marketplace standards. Its customers will see them as a quality organization. Its employees will enjoy job satisfaction and the plant will realize continuing profitability. Every industrial plant aspires to achieve ?world class? status knowing it can compete favorably with the best, most profitable organizations in the world. The trick is to achieve the attributes that qualify your organization for world class status. But there are no world class maintenance organizations. Rather, there are world class industrial organizations that include a world class maintenance organization. Maintenance, by itself, is a service provider, dependent on the support and cooperation of other departments. When that service is exceptional, it is made that way because maintenance is operating in a plant environment that requires it to be exceptional. Managers have created an environment in which maintenance can be exceptional. The plant, mine or facility manager must acknowledge from the start that maintenance is not a stand-alone effort of a plant maintenance department. It will require the joint efforts of all plant departments. Quality material support and full cooperation from operations, for example, are among the essential requisites for effective maintenance and achievement of world class maintenance status. When attributes such as these are reinforced by dedicated plant managers, profitability soon follows.

By Y. J. Wang

This paper describes a graphical technique by which the operating points for a two-fan ventilation system can be represented as the intersection of the modified fan curves. In constructing the diagram, the air quantities associated with the fans are considered to be independent variables and employed as the axes of a rectangular coordinate system. The diagram may include, in addition to the modified fan curves, contour lines for resistances, pressures, and air powers. Procedures for drawing the diagram are discussed and illustrated with an example of the ventilation system.

Jan 1, 1985

By A. A. Davis

The decade of the 70?s saw a series of landmark environmental resource programs enacted by the Congress. Many states followed suit, so that by the end of the decade air quality, water pollution, and the conservation of other natural resources, including minerals, were the subject of a wide-ranging body of laws, policies, regulations, and procedures. Many of the actions required or permitted by this rule-making involved areas for which adequate information and substantial experience were not available. Moreover, goals and objectives were sometimes established which were enormously difficult to achieve technically, or of such formidable expense as to cause concern about their consequences in the marketplace. It is therefore hardly surprising that one product of all this activity has been a mass of litigation. Court dockets are crowded with suits and counter-suits involving both substantive and procedural aspects of environmental protection. Indeed, it is probably fair to say that the volume and range of environmentally-related disputes brought before the courts parallels that generated by the civil rights movement a decade ago. There were also some new dimensions to the environmental movement. For the first time, the national environmental policy act required agencies to prepare environmental impact statements when proposed projects or activities would have substantial impacts on environmental resources. Another requirement of many of the new programs mandated meaningful citizen participation in public decision-making. Here, as elsewhere, the purpose was admirable, but guidelines were vague, and the result often was inaction, polarization, and litigation.

Jan 1, 1986

By Frank H. Skelding

A new, large mine is about to be born. Many years and millions of dollars have been invested in exploration. An orebody has been found and proven. All necessary political and legal work to establish rights and conditions for development are complete. The feasibility studies are favorable. Financing has been arranged. Board approval has been given to proceed. The time has come to engage a contractor to design and build the new facilities in a location, as is the common case today, far re¬moved from the centers of advanced technologic development where the minerals will ultimately be used. A select list of Engineering and Construction (E&C) companies is asked to prepare proposals. At this point the common viewpoint among mining companies is that the company's sole remaining problem, a major one to be sure, is to select qualified contractors to design and build the project at the lowest cost and shortest time possible so that production can start generating a return on investment. The purpose of this discussion is to explore the viewpoint of the large E&C contractor toward such projects. It differs in important ways from that of the client mining company and it is these differences and the reasons for them that must be understood by the client if severe difficulties and misunderstandings with the contractor, starting at the beginning of contract negotiation and continuing through design and construction to final startup are to be avoided or minimized. Often enough, the difference is in degree, not kind, which only serves to obscure the fact that a difference exists.

Jan 1, 1975

By W. E. Benton

Diatomite or diatomaceous earth is a siliceous sedimentary rock principally made up of the skeletal remains of the diatom, a microscopic, single-cell aquatic plant related to algae. The unique structure, chemical stability and physical properties are the major attributes of diatomite not met by other forms of silica. The production of diatomite was down in 1982 vs. 1981, reflecting the worldwide recession. The principal markets for diatomite products continue to be basically filtration and fillers. The outlook is for small but steady growth into the 1990s.

Jan 1, 1983

By Nasri Munfah, Raymond E. Sandiford

"Superstorm Sandy (Sandy) created a storm surge that inundating many of the tunnels that pass beneath the Hudson and East Rivers. The tunnels are vital infrastructure links for the economy of New York City and the northeast region. The sea water, which contains highly reactive salts, caused significant damage to electrical and mechanical systems. In addition, the salt water inundation left corrosive precipitants on the tunnel linings and on and within electrical duck banks. After the salt water was evacuated from the tunnels, condition assessments were performed using a state of the art approach involving high resolution laser scanning, digital imaging, and thermal imaging. These scans were performed prior to hands on inspections. The damage assessment concluded that, although the tunnel structural linings were not damaged, the interior elements of the tunnels needed major rehabilitation to arrest the continual deterioration of the structures. This paper details the state of the art approach used for these tunnel inspections. INTRODUCTION On October 29, 2012 Super Storm Sandy flooded a large number of both transit and vehicular tunnels in the New York Metropolitan area. The region’s transportation network was severely disrupted. The storm damage is estimated to have been in excess of $30 billion, and with the tunnels out of service, the local economy was losing hundreds of millions in economic activity. Restoration of these tunnels was a very high priority and the resulting expedited restoration process did not always provide adequate time for comprehensive condition surveys. This resulted in many of these surveys being conducted after service restoration. Inspecting highly trafficked transit tunnels is challenging and the logistics of working in short night outages led to a rethinking of the conventional inspection approach. Traditionally, visual and tactile methods are first used to inspect tunnels and then quite often followed by LiDAR (Light Detection and Ranging) scanning and perhaps infra-red scanning. For multi-mile tunnels, the time required to visually map tunnel features can be quite extensive. By performing the scanning first and then performing the visual and tactile inspections, one is able to use the scan data to identify the specific areas that need detailed inspections. This approach was used quite successfully for a number of the NYC tunnels."

Jan 1, 2016

By Richard J. Leary

At the 1976 Annual Meeting of AIDE, Alan Merson reminded his audience that economic' success comes to those who understand things as they are, rather than as they have been or what ideology says they should be (1). He went on to say that, measured by this standard, the mining industry is in trouble. The mining firms had recognized long ago the importance of effective lobbying in Washington and the state capitals. But, he pointed out, those methods are nearly worthless anymore in coping with many land use problems because the critical decisions are likely to be made at the local level. There the tactics are far different as are the relations of the decisionmakers to the parties before then. Furthermore, in his estimation the trend is to leave land use regulation largely to the local level of government. All who are concerned for access to land for mineral development will be benefited by reading Professor Merson's paper lie is speaking effectively about the context of decisionmaking for specific cases, the shape of things in the here and now. There is, however, a longer-tern set of considerations that if pursued will be likely to foster the creation of public support for mining developments. At that sane meeting I spoke on two foundations of the long-term relationships: namely, the growth in requirements for minerals implied by projections of increasing consumption; and a rationale for fostering mineral exploration and development. I mentioned in passing the social decisionmaking process for public uses of land (2). This paper is intended as a complement. The growth of requirements for Minerals and the rationale for development based on the Entropy Law will be only mentioned. The main concern will be on the process of social decisionmaking in the context of access to land for mineral development.

Jan 1, 1976

By K. J. Stratford

The selection of a suitable mathematical function for the modelling of the partition curve for dense medium cyclones is discussed. Five alternative functional forms (based on three basic functions) are compared using data obtained in the course of an extensive experimental study of a 610mm dense medium cyclone. It is shown that, for adequately sampled tests, any of the functions may be used, although a function based on the Weibull distribution is shown to be most suitable. Where data are poor, all functional forms exhibit disadvantages, notably in terms of a reduction in precision of parameter estimation. This problem can be exacerbated by the complex numerical techniques required to estimate the parameters of a particular function. A set of ideal requirements for a performance function are presented.

Jan 1, 1986

By Anil Kumar

In underground mine production units that employ discrete-vehicle face haulage, feeders are used in the belt network so that vehicles can unload rapidly without transmitting to the conveyor network the high material flow rates that result from rapid unloading. They prevent production bottlenecks at the face, while reducing capacity requirements for downstream materials handling equipment. Similarly, surge bins may be installed at intermediate locations in the network to smooth flows from a number of upstream sources, thereby reducing downstream belt capacity requirements. This paper introduces new stochastic process models to temporally describe loading patterns from unit operations and techniques for computing the probability of various fill levels for the feeder or surge bin. These results may be used to analyze the effect of alternative bin or feeder capacities and discharge rates on the performance and costs of the materials handling system.

Jan 1, 1994

By John J. McCrone

In the Mining Industry, the means of handling and transferring lubricants has been given little attention over the years. An analysis of this process indicates that this neglect has often exacted a very high price. As the costs associated with labor, equipment utilization and waste disposal soar, the need for an efficient system takes on an increasing significance. Often the focus of bulk systems has been placed on the master container itself. Certainly, there is nothing new about a large lubricant container; they have been available over a period of years, known under a variety of names, "mini tank", "super drum", ?flo-bin" and "tote bin", to name but a few.

Jan 1, 1982

By Walfrid Been

There are no particular nor unique features of iron mining that are not shared in some degree by all mining ventures everywhere. There are, however, at least three problems that have acquired a special emphasis from a unique cause. That cause is the embarrassment of riches under which the industry is suffering. The most obvious' feature of iron mining today is the copious abundance of usable ore and its almost universal distribution over the face of the earth. By the term "usable ore" is meant ore that is amenable to reduction by the usual and conventional processes. Amidst this plenty, three problems become acutely emphasized: 1. The geographic location that will provide a mine with the best market opportunity. 2. The size of the orebody that will be required to' return the preproduction investment. 3. The geometry and configuration of the orebody that will permit quality control measures to be effectively executed.

Jan 1, 1964

By Larry S. Diaz

It is felt that prior to the presentation of the technical portion of this paper, some general information would be of interest. The Sar Cheshmeh Copper Mining Company was founded by the Iranian Government to oversee the design and construction of Iran's first copper smelter complex, which will be another step in the industrialization of Iran. Since this is the first such plant in Iran, Sar Cheshmeh wisely chose to enlist the technical assistance needed in regard to the facilities requiring engineering and operating know-how from outside of Iran. To obtain the foregoing, SCCM signed a contract with Anaconda-Iran, Inc., which was formed by The Anaconda Company for this project. The general scope of this contract covers the overseeing of engineering and design by Parsons-Jurden as well as physical plant construction. In addition to this, the same services were given to water supply and tailings disposal systems which were not included as part of the Parsons-Jurden contract. Anaconda-Iran is also assisting SCCM in setting up a training program for Iranian personnel for plant operations, administration, etc., which .will go on for some time after the plant startup, under the guidance of Anaconda-Iran expatriates. SCCM?s other responsibilities, in respect to the development of this industrial effort, are the building of a townsite for approximately 2200 families, the expected manning requirements, having all the facilities necessary to provide a pleasant life in a remote area. It has been estimated that the manpower for operations will be 2050.

Jan 1, 1976

By G. Schmelzer

The disposal and reintroduction into recycling of residues produced by today's industrial society is not only a problem of much public debate in the countries concerned but also an increasingly prominent topic in science and research. In the treatment of most types of waste, ecological as well as economic considerations are important factors. In view of this, not only will future expenditures for treatment and processing become more significant but also, on the other hand, the savings and profits resulting from recycling. The situation described above reflects the inherent problems in the treatment of solid residues produced by waste incineration plants. The incineration of municipal waste produced approx. 2.7 - 2.8 million tonnes of solid residues in 1993 in the Federal Republic of Germany, which in part included still considerable amounts of organic and inorganic pollutants that could potentially be released into the environment. The most significant of these in terms of volume is incinerator ash at approx. 2.4 million tonnes. Through the use of innovative processing techniques, attempts are being made to convert the residues into a form that remains environmentally neutral over the longest period of time possible. One such group of techniques includes smelting technologies. After it has undergone specialised treatment, mineral incinerator ash is converted into environmentally neutral and reusable glass (vitrification) since, besides a reduction in the volume of the residues by approx. 90%, the main goal is a complete immobilisation and destruction of inorganic and organic pollutants respectively. These glasses, after they have been reshaped, are resold as commercial products such as damming or form glass.

Jan 1, 1995

By Lane White

The nature of the new Mining Law in Mexico, how it works and its implications for foreign investors were discussed from a variety of points of view by speakers participating in SME's special programming on Mining in Mexico at its An¬nual Meeting in Albuquerque, NM Feb. 14-17, 1994. Following are summaries of three papers whose primary objective was to give foreign investors some insight into the nature of doing business under the current Mexican Mining Law and its regulations. Lane White, Publisher.

Jan 1, 1994

By R. R. Tatiya

The selection of a mining method for a particular deposit must be based on certain technical and economic criteria. This can be interpreted as maximizing extraction and productivity while maintaining safe working conditions and minimum costs. The methodology developed here examines some of these aspects. The proposed methodology was tested on copper deposits that could be mined by underground stoping methods such as sublevel stoping, cut-and-fill stoping and their variants. In general, it provides a practical approach to both method selection and optimum stope design for base-metal deposits.

Jan 1, 1998

The strength of anchorage of various types of roof bolts in permafrost depends on the types of rock in which they are installed. Variation in the mine thermal regime results in weakening of the roof and walls, and at times total loss of ice cement bonds takes place in the surrounding rockmass. In mines with positive ventilation air temperature, the wedge or expansion types of bolts may become weakened due to the transfer of heat into the anchorage through the metal rod and subsequent thawing of rocks. Effective operation and evaluation of roof bolt systems for mine workings in permafrost require predictions of the dynamics of wall thawing by warm ventilation air. This paper presents an analysis of the temperature distribution in the frozen host ground surrounding roof bolts, the area of interest being the vicinity of the anchors for point anchored bolt and the entire length for split set bolt

Jan 1, 1994

By T. H. Jones

Fall of ground is a leading source of worker injury and fatality indicating a persistent need for ground monitoring technology. The HRTMM is an experimental convergence monitor utilizing a digital camera and custom software to track the position of one or more lasers across the target. Apparent laser movement is proportional to target convergence. The HRTMM was installed in an underground mine near active operations to test its response to the mining environment. This included intense blasting vibration and mine fog. Results and potential of the new monitoring technology will be discussed.

Jan 1, 2008

By Rebecca A. Miller, Terry M. Hertel

In-pit identification of neutral waste rock at the Zortman and Landusky minesites in Montana, by visual and chemical analy­ses, will assist in proper segregation and placement of rock so that soil and water resources can be protected. The use of too few or very general segregation criteria to identify neutral waste rock can result in ineffective waste rock segregation. Conversely, the use of overly restrictive criteria can result in the unnecessary loss of valuable reclamation material that would otherwise have to be mined elsewhere and hauled to the site. Recognition of nonre­active materials can be accomplished on a site specific basis with the use of visual observation and simple chemical analyses. The choice of chemical parameters used to analyze rock samples is constrained by the length of time needed to conduct the test. These analyses must require no more than 24 hours to complete so mining can proceed without delay. Limits set for the chosen parameters must be reasonable and defensible. To achieve these objectives over one thousand samples were collected at the Zortman and Landusky minesites and clas­sified by rock type, total sulfur content, paste pH, and net neu­tralizing potential (NNP). In addition, over 22 humidity cell kinetic tests were conducted to help corroborate static results for waste rock. Another 8 humidity cells were configured in series to test waste rock blending and waste rock/limestone capping alternatives as mitigation for acid rock drainage. Leachates were analyzed for pH, conductivity, alkalinity, acidity, sulfate, Al, Cd, Cu, Fe, Mn, Zn, Mg, and Cr in some cases. Petrographic analysis, as well as total sulfur content, paste pH, and static and kinetic test results identified three geochem­ically different waste rock groups: 1) Archean amphibolite gneiss and Paleozoic carbonates and shales, 2) Tertiary syenite porphyry, and 3) other less abundant Tertiary igneous and Archean metamorphic rocks.

Jan 1, 1996