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By H. Beecher (Original by) Charmbury

Water is a most remarkable substance, essential for life of all kinds. As well as needing water to survive, man has always used it for agriculture, transportation, recreation, and many other things. When our country was young and inhabited by few people, the streams, rivers, and lakes were able to provide all the clean water needed by man and take away all the wastes created. However, with our growing population and an ever-increasing demand for goods and services, the public, industry, and government at all levels have become acutely aware of the need to manage the nation's water resources more efficiently. Abundant energy from many sources has helped this nation to become the greatest industrial nation in the world. Coal has contributed a major portion of this energy, generating electricity, running railroads, and maintaining national security during wartime. The result has been the highest standard of living in the world and a time of widespread economic prosperity. The use of water in coal mining is somewhat different from its use in most industries. With the exception of water used in cleaning plants, for underground dust control, and for fire protection, most of the water en- countered in coal mining operations serves no useful purpose. In other words, it is an undesirable element and must be removed, otherwise it will interfere with operations, cause potential water quality problems, and may even stop operations by flooding. In the past, removing water from working areas of most mines was usually a fairly simple matter. Pumps with piping were installed at sumps or low spots in the mine and the water was pumped to the surface or to drainage control facilities constructed for the operation. Ditches were often used to collect and drain the water by gravity to the outside or to main sumps for pump discharge. In either case, the water was allowed to flow into the nearest stream or river. The concept of "water is water' was generally accepted without too much concern for what was in the water since low-cost products and services, rather than clean water, were the public demand.

Jan 1, 1981

By Changwoo Lee, Jan M. Mutmansky

Introduction Recognition of Coal Workers' Pneumoconiosis (CWP) as a major occupational disease has affected various aspects of the coal mining industry in the United States as well as in almost all major coal producing countries. Regulations related to the control of coal mine dust forced mine operators to modify their mining and ventilation practices. As the coal production record of the last 15 years shows, this had both direct and indirect impacts on the productivity and production costs. To identify the causes of CWP, many research efforts have been made through- out the world. Most of these studies were epidemiological in nature, attempting to pinpoint exposure and seam variables that affected the incidence of the disease. Other studies have been oriented toward the elemental and mineralogical composition of the coal dust in the mine atmosphere and in the miners' lungs. These studies indicate that there may exist some relationships between the characteristics of the coal mine dust and the prevalence of the disease. Some of the variables that are thought to affect the occurrence of CWP are the mass of the dust in the working place, the rank of the coal, the existence of certain trace elements, the free silica content of the coal, and the existence of other minerals in the respirable dust. A more complete description of these previous re- search studies has appeared elsewhere (Mutmansky and Lee, 1984). The behavior of particles in the human lung is known to be governed by their aerodynamic diameter, which is defined as the diameter of a hypothetical spherical particle with unit density that exhibits the same settling velocity as the given particle. Because of this fact, the aerodynamic size distribution of coal mine dust is one of the parameters to be determined along with the other physical, elemental, and mineralogical characteristics. The objective of this paper is to establish a strategy for providing coal mine respirable dust samples for characterization purposes using instruments that classify according to the aerodynamic diameter. In addition, several findings concerning characterization methods will be presented. Choice of Samplers Most of the gravimetric dust collection devices that can be utilized in a mine environment can be

Jan 1, 1986

By Sarkis G. Ampian

This late 1979 Bureau of Mines report presents current stocks and monthly consumption rates for Guyanese refractory bauxite (GRB), with emphasis on the impact of the GRB shortage on the refractory and downstream industries, general background material, and an evaluation of the situation resulting from the strike of Guyanese bauxite workers during the summer of 1979. A study by the Bureau indicated that industry stocks contained little more than a month's supply of GRB--30,000 calcined short tons (CST), at present consumption rates of 25,000 CST per month. The report was requested by the Federal Emergency Management Agency (FW) in response to refractory industry requests that the Government release GRB from the National Stockpile to minimize forecasted industry problems. The report traces the historical innovations in the high-alumina and/or bauxite-type refractory products industry, eventually leading up to fabrication of modern, high-quality firebrick and monolithic refractories.

Jan 1, 1980

By M. Niec

Lignite deposits in Poland occur within clastic Tertiary series at the depth suitable for opencast mining. Aboundant aquifers with the good quality waters that should be protected against contamination or depletion often accompany them. Landscape and underground water protection are the main regional environ-mental factors that limit the possibility of exploration and mining; presented on map of lignite bearing series distribution allow to delimit areas "free" for exploration and mining and areas where some limitations can be met up to no admittance of any industrial activity.

Jan 1, 1994

By M. G. Ayat

Although other methods of mineral concentration have been developed over the years, gravity separation remains one of the most efficient and economical for cleaning coal. The concentrating table and the spiral separator are popular devices used for the separation of minerals by exploiting the differences in specific gravities of the product material and the gangue. While the former device has been servicing the coal industry for over 75 years, the latter seems to have not been employed extensively for coal cleaning purposes in this country. As far as coal preparation is concerned, both separatory devices seem to be most efficient for intermediate to fine size fractions. As it stands there exists a great deal of confusion amongst preparation engineers and plant managers as to whether spirals can have a place in the coal industry. If so, whether their come back is the beginning of the end for concentrating tables, or can they be employed along with concentrating tables to contribute toward more efficient cleaning processes resulting in an improvement in the overall economics of the coal preparation industry. This paper examines the efficiency of both systems for coal processing operations as well as the basic principles, operational variables, economics, advantages and disadvantages associated with each unit operation. Attempts have been made to draw conclusions and make recommendations as to which system would be more beneficial for coals of known characteristics.

Jan 1, 1986

By D. A. Norrgran

The recent development of rare earth permanent magnets has revolutionized the field of magnetic separation. The advent of rare earth permanent magnets in the 1980's provided a magnetic energy product an order of magnitude greater than that of conventional ferrite magnets. This has allowed the design of high-intensity magnetic circuits operating energy free and surpassing the strength and effectiveness of electromagnets. New applications and design concepts focused on the mineral and metal processing industries have evolved. This technology also led to the development of various magnetic separators specifically designed for mineral processing applications. Applications which were not previously considered are now being applied to primary mineral upgrading and recycling and secondary recovery.

Jan 1, 1993

By B. K. Cantrell, D. H. Carlson, W. F. Watts, K. L. Rubow

The use of diesel equipment in underground coal mines is controversial because the National Institute for Occupational Safety and Health (NIOSH) regards "whole diesel exhaust" as "a potential occupational carcinogen." Threshold limit values (TLVs) are recommended for the gaseous pollutants CO, CO2, NO, N02, SO2 and some hydrocarbons emitted in diesel exhaust. There is, however, no TLV recommended for diesel exhaust aerosols (DEA) nor is there a standard method for sampling these aerosols. The University of Minnesota and the USBM have collaborated to develop a personal diesel exhaust aerosol sampler (PDEAS) that utilizes size selective, inertial impaction and gravimetric analysis. During the field tests of this sampler, numerous air quality measurements were conducted in underground coal mines that used diesel equipment. The objective of this report is to present these data and to assess the impact of diesel face haulage equipment on mine air quality. Air quality data were collected in four underground coal mines. The mines used continuous miners and diesel haulage equipment. Daily samples were collected at the section intake, haulageway and on haulage vehicles. Both full-and partial-shift samples were collected using a variety of aerosol instruments. These included the PDEAS and the micro-orifice uniform deposit impactor (MOUDI) that sample the mine aerosol diesel exhaust fraction. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust CO, CO2, NO, NO2 and SO2. These measurements were made by either collecting bag samples for subsequent gas analysis or by Palmes dosimeters. Concentrations of CO, C02, NO, NO2 and SO2 were well below regulated levels. The mine average DEA concentration determined by the PDEAS in the haulageway for the three mines surveyed was 0.79 mg/m3, with a standard deviation of 0.19 mg/m3. DEA contributed 65% of the respirable aerosol, at this location. These results were the same as the mean DEA concentrations calculated from size distribution measurements obtained using the MOUDI. This was 0.78 mg/m3, with a standard deviation of 0.22 mg/m3.

Jan 1, 1992

By C. N. Bailey

Let's review the economic factors in mill design. Talking about engineering economics in mill design reminds me of an old' saying "There are several ways to handle women but nobody knows what they are." I'm sure that the same economic factors do not apply to each of our mill designs, but for the sake of emphasis, it is well to review a few of them. They are so simple that we are apt to feel they are not important. Other speakers today are talking about the engineering factors of mill design, but I'm asking the question "Have we checked the economic factors involved in these designs? Have we checked the obvious? Many great discoveries have resulted from analysis of the things that appeared to be obvious all the time. What are some of these economic factors? Perhaps the most basic one is simply the value of minerals in place if minerals have value in the ground, they have value only because many important and different considerations add up to the probability that the minerals can be mined, beneficiated and disposed of profitably. The size formation and quality of the ore body, the distance from market, and the transportation available to the market area, depreciation rates, taxes, and the ownership interests involved are but some of the factors that must dovetail into the answer of profit, an answer prerequisite to hoped-for financing.

Jan 1, 1961

By K. W. Deter

The gold ores in the Jerritt Canyon district have been recognized as refractory since they were first encountered by FMC geologists in 1976. Upon obtaining managing rights as joint venture partner, Freeport McMoRan Inc. developed an operating plan featuring carbon-in-leach gold recovery techniques for the oxide portion of the ores and a patented sulphide oxidation step followed by chlorination for treating the organic carbon constituents of the refractory ores prior to CIL gold recovery. The plant was successfully started up in 1981 with the first gold poured on July 4, 1981. Initial plant throughput was designed to be 2495 MTPD (2750 STPD) total through the dual processing trains.

Jan 1, 1991

By D. J. Crawford

The Lucerne Valley Operations of the Minerals, Pigments and Metals Division of Chas. Pfizer & Co., Inca, are located about 5 miles south of the town of Lucerne Valley, California. These operations consist of several limestone quarries, a whiting plant which produces finely pulverized limestone products, a-kiln which produces granular quicklime and lime products, and maintenance shops, warehousing, shipping, and office facilities. Construction of the Lucerne Valley plant began in 1961 as the result of a decision to utilize large undeveloped reserves of limestone in that area. Quarry development was started in the following year; and by 1965, Lucerne Valley had become the principle limestone and lime facility of the Western Operations of the Minerals, Pigments and Metals Division.

Jan 1, 1967

By James Wonneberg, William Edgerton

"Today’s underground construction megaprojects are tremendous feats of engineering on a massive scale, excavating through ground conditions once thought impossible, using new and innovative contracting practices. But one important truth remains unchanged; projects are built by people. What separates winning projects from the rest? Great people, working in great organizations. In straight-talk fashion this paper sets forth fundamental differences between good project leaders and bad ones, on topics ranging from client relations, design management, and scheduling, to use of the whiteboard, and everything in between. Broadly applicable to all corners of project delivery, this paper will resonate with project leaders from around the world and help identify skills necessary to succeed in the management of underground facilities. A NOTE FROM THE AUTHORS This is a training document, and not really a “paper” per se. We have attempted to tackle some big and potentially complex topics using bite-sized paragraphs, each of which are intended to promote thoughtful introspection and dialog. So please feel free to skip around, or even set this document down while you reflect on your own personal experiences, tactics, and philosophies. We have found that providing examples of “what not to do” is oftentimes more instructive than simply listing “what to do”, hence the Good/Bad format of this document. Please note that “PM” refers loosely to anyone on the project management team not just the “Project Manager”. We also wish to preface this with the following cautionary statements: • The authors do not pretend to be the “Good PM” in all cases. In fact, we’re almost certainly the “Bad PM” for some. We aim to improve on those areas. • It has been said that “The only real training for leadership is leadership.” (Antony Jay) We all started somewhere, and nobody has 20 years of experience on day one. • Converting this text into some sort of prescriptive checklist would be a disservice to the evolution of project management. Our world – and our awareness of it – is constantly changing. We must always be open minded to new ideas and different perspectives on project delivery."

Jan 1, 2016

By Ernesto Maldonado, Jesus Romero Benitez, Zach Agioutantis

Numerous researchers worldwide have investigated the prediction of ground movements due to underground coal mining utilizing different analytical, empirical, and numerical models. These studies have primarily focused on the development of prediction methodologies for either flat or gently dipping seams under variable topography, and only a few studies are available that have investigated the prediction of ground movements over inclined seams. Although most inclined coal seams are in China, India, and other countries worldwide, a few inclined coal seams (with a dip of 10 degrees or greater) are also present in the US. Currently, the prediction of ground movements for inclined coal seams using empirical methods utilizes the same methodology for horizontal seams. It consists of dividing the inclined seam into horizontal segments, calculating deformations due to each segment, and superimposing the calculation results. This paper presents a new tool that provides a methodology for modeling subsidence under inclined seam conditions. Examples based on subsidence measurements available in the literature are presented. The goal is to implement this methodology into the Surface Deformation Prediction System (SDPS).

Jun 25, 2024

By Thomas J. DeMull

Amax Gold's Sleeper Mine was brought to production as an open pit mining, cyanidation milling operation in March 1986. The Sleeper deposit is unique in that it contains zones of very high grade gold ore. Despite blending of ore, mill head grades have varied over a broad range. These grade variations were anticipated during mill design and affected, in particular, the sizing and selection of equipment for the CIP circuit. When grades proved to be even higher than anticipated, design operating parameters were adjusted shortly after start-up to accommodate the higher grades. Operating results have been excellent: during the first 18 months of operations the Sleeper mill has processed 375,600 tons of ore and produced 229,000 ounces of gold.

Jan 1, 1998

By D. L. Crouse

The worldwide talc industry has experienced significant changes since the 1980's. Consolidation of companies and operations in Europe, Australia, and North America has altered the face of supply and distribution. Imports of Chinese and Australian crude have increased competition and product options. The number of processing operations without local mines has moved competition closer to the market area. Quality controls related to ISO certification and tighter specifications demanded by the customers have altered the way our mines and mills operate. Ceramics, coatings, and paper applications continue to consume the majority of processed talc.

Jan 1, 1997

Many investigators believe that column flotation cells offer significant advantages over standard mechanical machines for the flotation of fine particles. However, because of their unique design and operation, conventional techniques for flotation cell scale-up and design cannot be applied to columns. In an attempt to help alleviate this problems a population balance model based on first principles has been developed for fine particle flotation in a column. Two different terms have been considered in the model, i.e., transport and rate. Transport terms, incorporating fluid flow and bouyancy, are used to describe the movement of air bubbles, unattached particles and bubble-particle aggregates along the length of the column. Rate terms, which describe the bubble-particle attachment process, have been derived from first principle considerations. Because the model is based on first principles, it can be useful for the design, control, optimization and scale-up of column flotation cells.

Jan 1, 1987

By A. K. Sinha

Despite the tremendous efforts and costs incurred by the industry and regulatory agencies to prevent premature roof failures in underground mines, roof falls continue to occur frequently due to the very unpredictable geological conditions and dynamic nature of mining operations. In fact, roof falls continue to be the largest contributor to coal mine fatalities. The failure of a mine roof generally occurs following a prolonged, gradual degradation in its physical conditions. An electronic mine roof monitoring system has been developed and tested in operating mining sections. It monitors mine roof degradation on a continuous basis. The field test results are presented and discussed.

Jan 1, 1987

By Elmer R. Drevdahl

During the last few years there has been a rapid increase in the development of the community or junior college throughout the United States, Some factors behind this development include the need for more college facilities to service the growing number of high school graduates, the desire of the public to provide some post high school education at reasonable costs, and the need to provide post high school educational opportunities not now provided by most of the universities and colleges. Many of the new community colleges provide at least three educational services including local opportunity to provide the first two years of a four year college program, two year technical-vocational programs of a terminal nature, and adult educational opportunities. The community college has the advantage of not being saddled with years of academic tradition which prevent it from changing to suit the educational needs of the community It serves. The flexibility of the community college in developing new programs, particularly in the technical areas, is going to provide industry with many of the badly needed technicians it is now unable to secure.

Jan 1, 1965

By T. W. Eddy

Research was conducted in which elemental mercury and its sulfide mineral (cinnabar) are removed from a copper sulfide concentrate by low temperature thermal applications. The goal of this research was to reduce, volatilize, and collect mercury vapor from concentrated smelter feed in a simulated drying environment while maintaining the chemical integrity of the residual. The study used synthesized concentrates composed of copper sulfide and mercury bearing minerals (such as cinnabar (HgS) or elemental mercury) to determine optimal residence times and temperature ranges.

Jan 1, 1996

By A. M. Gaudin

In a recent paper we have reviewed principles and applications of measurement methods for contact angles and their hysteresis (22). In this paper we apply these methods to a system consisting of rutile, an organic liquid (benzene, decane, or dodecane) and water. Surfactant (dodecylamine hydrochloride) was used at various concentrations and various pH values.

Jan 1, 1964

By James P. Connell

The Montana Operations of the Anaconda Company constitute an integrated, though geographically separated, non-ferrous metal production complex. The mines are located at Butte and consist of one large open-pit mine, two small underground mines, a precipitation plant for both underground and pit-dump leach water, and the Weed Copper Concentrator. The smelter, located at Anaconda, Montana 25 miles to the west, processes all Butte copper shipments as well as copper materials from both Anaconda and private mines. Copper and zinc are refined at Great Falls, Montana, 165 miles to the north. Other facilities developed over the years include the Anaconda Forest Products Division, the Butte, Anaconda, and Little. Chicago Water Companies, and the Montana Hardware Company. Data processing for these operations has been performed on an IBM 360 Series, Model 30 computer, utilizing a Disc Operating System. This was replaced in September 1970 with a 360 Series, Model 40 128K unit. In addition, some data processing is also done for Anaconda Company operations located at Britannia Beach, British Columbia; Columbia Falls, Montana; Yerington, Nevada; and Twin Buttes and Tuscon, Arizona. The material under discussion in this paper will be concerned primarily with the mining operations at Butte.

Jan 1, 1970