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By James Westfield

This report covers the calendar year 1954 and has been prepared and submitted to the Congress of the United States in accordance with the provisions of Sec. 106(a) and Sec. 2l2(c) of the Federal Coal-Mine Safety Act (66 Stat. 692; 30 U.S.C. Sec. 451-483). Background The Federal Coal-Mine Inspection program was established to carry out the provisions of Public Law 49, 77th Congress, H. R. 2082, approved May 7, 1941. This act has since been amended to be known as Title I -Advisory Powers Relating to Health and Safety Conditions in Mines, under Public Law 552, 82d Congress, approved July 16, 1952, which also includes Title II -Prevention of Major Disasters in Mines. Public Law 552 is known as the Federal Coal-Mine Safety Act.

Jan 1, 1956

By K. L. Paciorek

The aim of the present study is to determine on a gram per gram basis the toxic products of the thermal oxidative degradations of selected compositions. Four families of materials were investigated under the subject contract namely polyvinyl chloride and neoprene compositions, rigid urethane foams I and woods. Three methods were employed to conduct the thermal oxidative degradations: a sealed system (quiescent environment) I a stagnation burner arrangement (dynamic environment) I and a flow-through apparatus (dynamic I but less severe than stagnation burner conditions). The majority of tests were conducted using the first two systems; only limited experiments were carried out employing the third decomposition procedure. All decomposition was done at temperatures of 370 -4000C I the higher temperature being used in the stagnation burner. It has to be stressed that the nature of the products and the relative product concentration are temperature dependent. Thermogravimetric and differential thermal analyses were performed to supplement and extend the above delineated studies and to explore the feasibility of using these analyses as a method for material differentiation.

Jan 1, 1973

The Use of Automated Mineralogy to Interpret the Batch Flotation Performance of Merensky Reef Ore

Sep 13, 2010

By C. W. Davie

"This paper is the second of a series of progress reports4 on a study of the hydrometallurgy of manganese which is being conducted in an endeavor to make possible utilization of the large deposits of low-grade domestic manganese ores that occur in several States.There are at least four processes in which a knowledge of the action of SO2 gas on manganese oxides at elevated temperatures may prove of value.One of these involves dissolution of manganese from ores. The Bureau of Mines has investigated the hydrometallurgy of manganese by a process in which SO2 gas, a waste product at many smelters, is passed into water to form a solvent for manganese. Although several manganese minerals were readily dissolved, rhodochrosite (MnCO3) was attacked but superficially.5 Recent experiments have shown that a roast at 650 to 9000 C. converts the manganese of rhodochrosite to a form that is quickly dissolved by a weak SO2 solution.6 Introduction of smelter gases containing much as 5 per cent SO2 during such a roast would not add much to the cost of the operation, and might result in the formation of considerable water-soluble manganese sulpate.Another case involves a subsequent step in the hydrometallurgical process, namely, the formation of oxides of manganese with simultaneous evolution of SO2 by the heating of the MnSO4 produced by evaporating its solution.A third has to do with the roasting of zinc sulphide ores containing manganese as a preliminary to leaching. During purification of the solutions to be used for the electrolytic deposition of zinc the iron must be oxidized to make possible its removal. Manganese dioxide has been used for this purpose,7 and since manganese compounds are present in some zinc concentrates,8 it is of interest to learn what happens to the manganese in a zinc sulphide or on roasting, and what portion of the manganese in the roasted product might be available for oxidation."

Oct 1, 1930

By Tano Balbin, Valery Astakhov, Juha Timperi, Lauri Koresaar

"Online elemental analysis is the basis of optimal flotation control in mineral concentrator plants. Traditionally XRF analyzers have been used as the online analysis method. However, online XRF analyzers struggle to measure elements below calcium in atomic number (Z=20). For many processes lighter element assays would be beneficial to improve control of grade and recovery. Processes where elements below Ca are required include P, Mg and Si in phosphate concentrators, Si, Mg and Al in iron concentrators, and S and C in gold concentrators. Laser-Induced Breakdown Spectroscopy (LIBS) based elemental analysis can readily be applied to these processes. LIBS is based on generating plasma in the slurry sample by a high energy laser and analysis of the plasma by optical emission spectroscopy. Capabilities of a new Courier® 8 analyzer based in LIBS technology are demonstrated for elemental analysis starting from lithium (Z=3). Results of a plant installation in a sulfide gold concentrator provide a good agreement with the analyzer and laboratory assays.IntroductionEffective process control can be regarded as one of the fastest paying investments for a mineral processing plant. Process optimization in flotation circuits requires constant feedback of the process state. If only manual laboratory samples are available, this optimization becomes difficult due to the long delay between taking the sample and acquiring the laboratory result. If the element grades are available in online basis, the operator or automatic process control system can make corrective actions in real time.Online X-Ray Fluorescence (XRF) analyzers have been in use at concentrators for decades. The XRF analyzers can provide a fast, accurate and precise analysis from slurry streams. However, the drawback of XRF analyzers is their lack of capability to measure elements below Ca (Z=20) in atomic number. The low energy X-rays of the low atomic number elements get absorbed by water in the sample, protective window of the analyzer, or air between the sample and spectrometer."

Jan 1, 2017

By G. Adderley, A. Wetherelt

The problems of poor drilling in underground operations have been highlighted on many occasions. Incorrect collaring and poor angular deviation can all lead to an increased block size, dilution, over-break adding to both cost and time, while in a tunnelling operation sidewall damage and a poor percentage pull from a blasted round has similar consequences. This paper sets out to further investigate the ability of the laser scanner method of obtaining drill hole deviations and collaring errors at the face as described by Wetherelt and Williams (2006). Tests were carried out to compare measured inter-hole burdens from this method in comparison to that obtained using a total station survey. To investigate the ability of these methods to accurately determine drilling errors, a field test was carried out through an analysis of a series of pre-drilled blast holes of known inclination and direction. A time-motion study was also conducted for a varied number of holes to assess the usability of each method. In line with current research into blast vibration being undertaken at the Camborne School of Mines, 6 cut blasts were carried out to establish the effect of poor drilling on a blasts success to see whether an increased burden at the toe of a hole had an influence on vibration.

Jan 1, 2009

By Ralph P. Hackl

Ore at the Congress gold property, located near Goldbridge, British Columbia, is extremely refractory with most of the gold disseminated in fine-grained arsenopyrite. Metallurgical testwork conducted by Giant Bay Biotech Inc. indicated that biooxidation pretreatment was capable of increasing cyanide gold recovery from the ore to greater than 90%. To determine if the bioleach process could be successfully scaled up, a 225m' (7950-cu ft) commercial size bioleach reactor was built and tested at the mine site in 1989. At that time, the tank was the largest bioleach reactor ever operated. The objectives of the program were: • to ascertain if the biooxidation rates obtained in lab and pilot-scale reactors could be duplicated in a commercial scale tank; • to identify agitation conditions under which the process will function optimally; and • to demonstrate the bioleach process on a scale sufficient to satisfy the owners and potential investors.

Jan 1, 1990

When the HSE Act was introduced in New Zealand in April 1993, one of the prime aims of the Government was to signal to the industry. The Government's recognition of the employer as the key person responsible for safety and health in the workplace and to actively encourage employers to self manage the health and safety function. Because of the significant change in the philosophy behind the new legislation, and because of the inherently conservative nature of the mining industry, it has taken some years for both the industry and the regulators to reach the stage of considering the framework in which a controlled degree of self management can proceed.   In this paper, some of the issues relating to the legitimacy of the process are considered, some of the questions raised in the minds of those charged with implementing the legislation are discussed, and the views of some eminent authors are examined.   The latter part of the paper focuses on a programme called the Reduced Site Surveillance Programme, which grew out of Goal 2 of the New Zealand Mining Inspection Group's 5-Year Strategic Plan. The programme is described in some detail, and the criteria applied at each stage of the programme is discussed. The paper concludes with the author's expectations of the longer term outcomes of the programme.

Jan 1, 1997

By W. E. Coughlin, R. L. Faverty, F. H. Lightner

Introduction The intent of this paper is to present the general strategy and method of implementation to achieve a "fast-track" mine development. The major objectives of a "fast-track" or rapid development schedule are to minimize front-end development expenditures and to realize an early cash flow from operations. The Borealis project of Houston International Minerals Corp. (HIMCO) is used as the working example to illustrate the development schedule. Borealis is a 2.3 kt/d (2,500 stpd) gold-silver heap leach operation near Hawthorne, NV, Pre-Feasibility Planning Proper early planning and identification of priority items were necessary to expedite project progress. On April 1, 1978, HIMCO leased the rights to the Borealis prospect and initiated exploration activities almost immediately. Since Borealis was showing excellent potential for mine development, an effort to clear the way environmentally was initiated during the summer of 1979. With the Borealis properties located within the Toiyabe National Forest, the US Forest Service (USFS) was recognized as the "lead" or respon¬sible agency for addressing the environmental issues. Early scoping of the environmental issues by both HIMCO and the USFS allowed HIMCO to take the initiative and address two potentially critical issues-archaeological and biological. Third party consultants, agreed upon by HIMCO and the USFS, were contracted to conduct archaeological and biological surveys. Desert Research Institute of Reno, NV, provided archaeological services, and JFL & Associates of Boulder, CO, provided biological services. These efforts began in the fall of 1979 and continued through the summer of 1980. Conservative Design Criteria By adoption of conservation design criteria, flowsheets and processing data required for detail engineering were firmly established with a minimum of impact on schedule. On Oct. 21, 1980, HIMCO formally initiated a feasibility study to evaluate the Borealis project. Four organizations were contracted for particular scopes of work: • John T. Boyd Co.: Ore reserve estimation, preliminary mine plan, and mine capital and operating cost estimation. • Bechtel Civil and Minerals: Conceptual engineering, processing capital and operating cost estimation. • Hazen Research Inc.: Metallurgical testing. • Sierra Pacific Power: Cost estimation for power supply. Metallurgical testing and conceptual engineering of both heap and agitation leach flowsheets were investigated concurrently. Numerous economic evaluations were conducted for both heap and agitation leaching at varying production capacities. The results indicated a heap leaching flowsheet treating 454 kt/y (500,000 stpy) yielded the best economics and was compatible with the "fast-track" development goal. Conservative design criteria was established to provide operating flexibility and ensure plant productivities. A summary of major design criteria is presented in Table 1. HIMCO assembled the results of the studies of the various consultants along with internally generated studies to produce the feasibility document. The decision to supply 100% equity by HIMCO rather than arrange project financing help to expedite the project. Cooperation Between HIMCO and Regulatory Agencies With cooperation and mutual trust established between HIMCO and regulatory agencies, the time required for environmental permitting was streamlined as much as practical. To expedite the required construction permits, HIMCO proposed to the USFS that HIMCO fund the total cost of an Environmental Assessment Report (EAR) and that issues be addressed at the technical level of an Environmental Impact Statement (EIS). The previous studies on the critical issues of archaeology and biology provided HIMCO with the information to satisfy the proposed approach. Houston International Minerals and the USFS agreed to have Environmental Research and Technology (ERT) of Fort Collins, CO, prepare a draft EAR for the USFS.

Jan 11, 1983

By A. Whillier

The decisive action taken by mine managements in recent years has been the main factor in bringing about the present downward trend in mine fires. A better understanding of the fundamental factors that govern the ignition and spread of fires. obtained as a result of investigations into mine fires, has provided useful guidance to production personnel. Similar investigations into fire-fighting techniques have assisted the Rescue Training Service and mines to institute more effective fire-fighting techniques. Some of the more important findings of recent investigations in these areas are outlined.

Jan 1, 1981

By R. J. Watson, A. H. Juch

About half a million sucker-rod pumps are installed in oil wells in the U. S. alone. In Venezuela, too, the system is widely used; some 5,000, or 90 percent, of Cia. Shell de Venezuela's wells produce a total of 400,000 BOPD by this method. Most of the crude pumped is viscous, gassy and contains relatively small amounts of free water. API gravities vary from 90 to 16O; dead oil viscosities vary from 10 to 10,000 cp at the pump; and GOR's range from 100 to 2,000 cu ft/bbl. Pumps are set at depths ranging from a few hundred to 6,000 ft; the average setting depth is about 2,500 ft. From the literature, it appears that although recent years have seen significant progress toward understanding the rod pumping system as a whole, relatively little attention has been paid to those key items, the sucker-rod pump and the subsurface gas separator or gas anchor. Perhaps because of proration in the U. S., pump manufacturers have seemingly concerned themselves more with the durability of their product, achieved mainly through robust design and metallurgical know-how, than with its working efficiency. In 1963, CSV commenced a major rehabilitation and expansion of its heavy oil fields along the Bolivar Coast. The advent of the more efficient gravel-packed completion and of large-scale thermal recovery (mainly steam soak) operations resulted in well potentials *Now with B. I. P. M., The Hague, The Netherlands. greater than pump capacities. Hence, an urgent need arose to improve over-all pump efficiencies and to attack those special problems related to the production of both the extremely viscous and the hot, steam-laden crudes that formed an increasing proportion of the total stream. There followed a detailed investigation and testing program, carried out in close cooperation with a major pump manufacturer. This culminated in the introduction to the oil industry of a new line of sucker-rod pumps. Early Investigations and Experiments Field Tests Extensive field tests were carried out in three primary Bolivar Coast wells with an in-situ dead oil viscosity ranging from 400 to 6,000 cp. In these installations provision was made to (1) monitor bottom-hole pressures below, in and above the pump by means of pressure transducers, and record casing- and tubing-head pressures continuously; (2) measure accurately the annulus gas, as well as measure the tubing gas and liquid production from the well; (3) take special PVT samples of the well fluid; (4) measure power consumption of the prime mover; and (5) measure the rod loads at the polished rod. A typical test installation is illustrated in Fig. 1. It was established from the pressure transducers that with viscous oils, there is considerable flow resistance across the pump and gas anchor assembly. Pressure surges were observed over each pump cycle,

Jan 1, 1970

By N. B. Pundari

Proper selection of large walking draglines, based on sound engineering principles and field experience, has not kept pace with the large capital expenditures needed to buy these stripping machines. The use of large walking draglines for stripping overburden in US surface coal mines grows steadily, but equipment selection continues to pose problems. An improper size, model, make, or spoil reach selected for a particular stripping application results in additional, unnecessary coal production costs. Large walking draglines are being used to dig deeper tar sands at the Syncrude operations near Fort McMurray in Northern Alberta, Canada. This application is compared with typical deep digging operations and dragline use prevalent at typical US strip mines.

Jan 4, 1981

The Winton Basin is one of three Southland sub-basins. The oldest known sediments are Early Oligocene terrestrial shales, sands and lignites deposited in half grabens formed as a result of oblique extension. A marine transgression in the Oligocene deposited mid-outer shelf to upper bathyal mudstones. Shallowing of the basin and tectonic quiessence lead to limestone deposition in the Early Miocene. Regional tilting led to uplift in the north and east and deposition of terrestrial lignites and gravels across the basin and the basement high to the south.

Jan 1, 1992

By K. S. Liddell

Ultra fine grinding is becoming increasingly used in the mining industry over recent years. The development of large-scale units for high volume grinding of low value materials and concentrates has opened up new areas of economical metal extraction. The ability of stirred vertical mills to produce very fine particles with high surface areas, is providing mine operators with novel extraction possibilities within gold concentrate regrind for Biox or leach feed, Activox autoclave feed preparation and lime slaking operations. The paper will review design, operational and maintenance aspects of ANI-Metprotech stirred vertical mills, comparing these to tower mills, horizontal bead mills and attrition mills.

Jan 1, 2001

By J. Kortnik

Mining has always been, and still is, an activity which is vital for the development of mankind. This is because a predominant proportion of industrial products and energy is produced from raw materials that are excavated using mining methods. The need for environmental protection and the close proximity of urban settlements and mines in Slovenia have necessitated ever stricter requirements for the excavation of raw materials and introduction of more environmentally-friendly mining methods. This is achieved by implementing a closed eco-technological cycle of raw material excavation within the scope of mining methods. In surface mines, this means prompt reclamation of the degraded surfaces, and in underground mines the use of methods with minimized impact on the surface and on underground water. In underground mines, mining methods with backfilling installed according to the multi-barrier disposal system are the only ones that allow the possibility of implementing a closed eco-technological cycle of excavating raw materials. Various industrial waste materials are also included in the backfilling material in order to improve its strength properties. Backfilling consisting of several different waste materials is produced in the form of a composite. Before backfilling consisting of waste material composites can even begin to be used in mines, an environmental impact assessment of its suitability for mines needs to be made. In order to make such an assessment, a pressure leaching cell and an open diffusion cell were made, i.e. a pressure leachate test and a sorption test were developed. The two cells and the developed tests will enable the study of the influence of backfilling on the environment if installed in an underground mine. The pressure leachate test performed with the use of the pressure leaching cell simulates leaching from a consolidated backfill during the seeping of underground water into the backfilling material under pressure. The sorption test performed in an open diffusion cell simulates the flow of eluate leached from the backfilling material through the rock/geotechnical barrier. The two tests were developed in such a manner that they are performed either in succession immediately after one another, but they can also be performed separately at a certain time interval. The paper presents an assessment of the suitability of backfilling made of different waste material composites. Keywords: environmental impact assessment, multi-barrier disposal system, waste material composites, pressure leachate test, sorption test, pressure leaching cell, open diffusion cell, eco-technological cycle, mining methods with backfilling.

Jan 1, 2003

By R. R. Falier, W. E. Rice

"PURPOSE OF REPORTThis paper presents the results of a series of tests made by the U. S. Bureau of Mines in cooperation with The Ohio State University Engineering Experiment Station as part of an investigation on the use of fuel in kilns.This report is preliminary and gives only enough of the test data to illustrate results and show the reasons for the successes and failures of the method of firing investigated; fuller details will be included in the final report.PERSONNEL FOR TESTSThe investigation is conducted under supervision of P. Nicholls, supervising fuel engineer, of the United States Bureau of Mines, and G. A. Bole, research professor, of The Ohio State University. These tests were made under direction of W. E. Rice, associate fuel engineer, assisted by R. R. Faller, assistant fuel engineer, of the United States Bureau of Mines; H. C. Harrison, senior research engineer (until October 1, 1930), C. R. Austin, senior research engineer (since October 1, 1930), and H. K. Van Sohoick, junior research engineer, of The Ohio State University. M. J. Rice, field engineer, represented the manufacturer of the stoker.PURPOSE OF INVESTIGATIONThe general aim of the investigation is to develop more economical methods of using fuel in kilns and to improve the over—all efficiency of the process of firing by methods that will produce ware of better quality. One phase of this investigation is the burning of coal on an automatic stoker to gain the advantages of control, constant rate of application of heat, and ability to burn cheaper coal than can be used in the hand—fired furnaces of kilns. It a stoker in to be used it is desirable that the coot of the installation should be low, the control of operation simple, and the distribution of heat in the kiln as good or better than with hand firing. These desiderata were sought in the stoker and furnaces that were used for the tests described herein. The tests were made to determine whether it is feasible to fire a large kiln with a single stoker, whether the use of a single furnace simplifies control, and whether the admission of all the hot gam at the center of the kiln will give symmetrical distribution of heat."

Aug 1, 1931

By E. A. Metz

Ergonomics is the art and science that tries to understand the complex interrelationships among employees, their work environment, equipment, work methods and job demands. Coal and metal/nonmetal miners are exposed to a higher number of ergonomic risk factors than in non-mining occupations. In addition, studies have shown that these miners experience more degenerative disc disease and osteoarthritis than comparable industrial populations. A general discussion of the risk factors that cause overexertion injuries and disorders will be presented. In addition, the basic principles of ergonomics will be discussed with specific cases to show how successful programs have been developed. A successful ergonomics program should simultaneously improve health and enhance productivity.

Jan 1, 2002

By Charles F. Seemann

It is with considerable trepidation that I set out to defend "litigation" to Design Professionals (DPs), as a better method of resolving disputes than arbitration, in the light of my personal feeling that an increasing amount of America's productive process is being squandered in litigation. Newer methods of dispute resolution, particularly arbitration, are fashionable, and opponents of these schemes risk being viewed as cynical or self-serving. My quandary is heightened since for some smaller disputes, arbitration seems clearly the better choice. I must concede, for example, that when the cost of dispute resolution--i.e., the cost of the process (such as arbitrators fees, attorneys fees, etc.), plus the cost impact of the non-productivity of involved employees--approximates the amount of the dispute, controlling that cost may be as important as a correct resolution. This principle is particularly true for small disputes arising during the progress of a project; it is probably more cost-effective for all parties to resolve their disputes quickly than permitting the dispute to drag out.

Jan 1, 1988

By Thomas M. Barczak

Advancements in support technology have occurred to a large extent because of the demands of the mine operators. Shield supports are no exception. The most notable changes in shield technology in the past decade have been increases in shield capacity and life expectancy, which have increased by a factor of 4 and 7 respectively since the inception of the shield support 25 years ago. The purpose of this paper is to set goals for the future generations of longwall shields. These goals include: (1) 100,000 cycle life expectancy, (2) improved hydraulic diagnostic capability, (3) smart load control with adjustable setting pressure algorithms, (4) composite material design to reduce weight and increase shield width, (5) constant set leg cylinder design, (6) improved joint design to reduce wear and stress, (7) advancements in leg cylinder socket design, and (8) an instrumented shield to measure in-service structural component loading. These design issues will continue to push the envelope in longwall shield technology that has provided the safest and most productive mining system employed in the history of mining. In preparation for this, a historical examination of shield failures is made and recent trends in shield design are evaluated. Design practices to improve structural margins of current designs are also addressed.

By R. G. Peluso

Methods and results of studies to determine friction and shock losses encountered in auxiliary face ventilation systems utilizing flexible, spiral-reinforced ventilation tubing are presented. The results, tabulated in graphic form, simplify fan selection and enable mine operators to design adequate auxiliary ventilation systems. Problem illustrates the use of graphs.

Jan 1, 1968