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By P. H. Williams, D. J. Morris

The co-disposal of coarse and fine coal wastes by combined pumping through a pipeline to subaerial deposition was pioneered in Australia in 1990 by Jeebropilly colliery in Queensland. Significant segregation of fines is found to occur in its co-disposal delta, leading to the formation of distinct mainly coarse upper and fine-dominated lower segments; the upper delta drains rapidly and is able to support traffic on its surface immediately after deposition. An existing theory of subaerial deposition, originally developed for mine tailings alone and later extended to trial co-disposal, is shown to apply also to the upper segment of the full-scale Jeebropilly delta

Jun 19, 1905

By Y. X. Tong

The simplicity off Ø=0 analysis has been taken advantage of to evaluate the geotech­nical problems of open caissons, slurry trench walls and piles in Shanghai. Undrained shear strengths obtained by various testing methods are correlated with case record and experimental data. Some problems posed by the construction of tall buildings are briefly discussed. Comments on applications are made to help engineers deal with practical problems.

Jan 1, 2010

Provide an unobstructive means of measuring small changes in distance from roof to floor or from rib to rib of a mine opening and the rate of closure in order to help operators of under-ground mines detect hazardous ground conditions. Approach A small ultrasonic measurement system was developed to detect g round movement and define closure rates. How the System Works The system contains two parts: a transducer and a readout device. The small ultrasonic transducer, similar to an audio speaker diaphram, is plucked with an ultrasonic frequency every six seconds. This frequency wave is sent through the air and reflected back to the transducer off any surface at which the transducer is pointed. The amount of time needed by the ultrasonic wave to make this round trip is accurately measured using a precise oscillator / timer and is converted into a measure of distance. The accurate 6-second time interval is used to convert any subsequent changes in the reading to a rate of change in feet per minute. Two readings are then displayed alternately on the readout instrument.

Jan 1, 1984

By R. D. Brown

The first step in achieving a rationalization of Canada's crazy patch-work quilt of mining taxes and policies was achieved with the release last November of a major federal-provincial report on the taxation of the Canadian mining industry. The Report, prepared by a group of federal and provincial civil servants, sets out a concise and informative discussion of the major taxation and incentive issues facing the mining industry, and puts forward major recommendations for more rational and moderate taxation policies. It will be considered by federal and provincial Finance and Resource Ministers for possible action by the respective governments. The Report was prepared in response to a directive from the federal and provincial First Ministers in February 1978 to review the federal and provincial taxation of the resource areas. Although the Report is more successful in identifying problems rather than concrete solutions, and reflects some continuing differences of opinion between the governments involved, it does represent an important first step in a comprehensive review of our resource tax policies. This article summarizes the Report, which is some sixty pages in length. Although a detailed discussion of it is beyond the scope of this article, the report itself is recommended reading for those concerned about the current state of the Canadian mining industry.

Jan 1, 1979

By Tristan H. Jones

Beginning in 1987, miniature dataloggers approved by the Mine Safety and Health Administration (MSHA) were publicly available for sale. The principal among these was the model CR21XQM, manufactured by Campbell Scientific, Inc. These dataloggers had been tested and were deemed permissible by MSHA and thus could be installed in the return air of an underground coal mine. In 1996, production of all permissible Campbell Scientific dataloggers ceased due to lack of sales. Data collection with these dataloggers has been a staple of ground control research in the United States for decades, and, without them, or a replacement, the capability to monitor ground behavior is severely impacted. Since that time, any party requiring a permissible datalogger has needed to borrow one that was purchased during the production years. In order to fill this technology gap and ensure its own data-gathering capabilities, the National Institute for Occupational Safety and Health (NIOSH) has developed and refined its own miniature data acquisition system (MIDAS). On February 16, 2010, MSHA deemed the MIDAS to be permissible and approved it for use in the return air of an underground coal mine. The MIDAS is an intrinsically safe, 16- or 24-bit datalogger, compatible with a wide range of resistive, single-ended, and differential-type instrumentation. It contains enough data storage memory to operate for over a year with typical data rates and is efficient enough to do this on a single C-sized alkaline battery for that entire period. It is menu-driven and requires no programming knowledge to operate. It supports wireless or hardwired communication for datalogger setup and data download. This paper describes the design, field and laboratory testing, and capabilities of the MIDAS datalogger. While not as fully -functioned as the CR21XQM, it is the only new permissible datalogger available, and there is intent to make it available to the mining industry for purchase.

Jan 1, 2012

By F. G. Scott

This document is a proposed program plan for mining environmental research to be conducted by the U.S. Bureau of Mines in support of industrial oil shale mining and processing. This program plan is one of three research alternatives being considered by the Bureau, each based on a different level of anticipated funding. This report documents the low funding level program plan.

Jan 1, 1980

By Stephen M. Jasinski

The development and industry adaptation of advanced technologies have led to many important uses for bismuth and its compounds. Bismuth-base alloys are essential for manufacturing jet engine turbine blades, lenses, and various safety devices, such as fire-protection sprinklers. The addition of bismuth to iron, steel, and aluminum imparts properties to these metals that makes them useful in diversified applications. Bismuth is also used widely in medicine, pigments, and electronics. The United States relies heavily upon imports from South America and Europe to meet its demand for bismuth, which is recovered chiefly as a byproduct of lead processing.

Jan 1, 1992

By Luke Keeney, Stephen Walters

"The start up of a new mining and metallurgical facility is a crucial step in the life of any mining project. The mining industries record is poor when evaluating processing plant operation relative to design capacity predictions made during feasibility studies. Multivariate geometallurgical orebody characterisation, using principle component analysis, is a method developed for improving predictive processing performance models during feasibility stages of mine development. This paper outlines the application of multivariate geometallurgical characterisation to the Cadia East deposit located in New South Wales, Australia. Cadia East is a low grade high tonnage copper-gold porphyry system in advanced stages of feasibility analysis. A dataset of ~32000 measurements and 150 comminution parameters (A*b and BMWI) has been used to develop class-based characterisation and modelling methodologies. The results of this study outline the development of class-based ore characterisation and provide a technique for analysing and interpreting large and complex geometallurgical datasets for prediction and optimisation of processing performance. The results enable sophisticated population modelling to be conducted which displays deposit scale processing variability, aiding circuit design specifications and predictions during feasibility studies.INTRODUCTIONA feasibility study is the major technical report on which the decision to proceed to production and on which financing is based (Shillabeer & Gypton, 2003). The mining industry’s record is not very good when actual construction time, costs, and operating performance are compared to the projections made in feasibility studies (Ballard, 1983; Gypton & Ward, 2000; Gypton 2002). A study by McNulty (1998) found that of 41 mineral processing and chemical plants built between 1965 and 1995, only 56% achieved design capacity within two years of commissioning and three were closed after failing to achieve design capacity within 36 months of start up (Shillabeer & Gypton, 2003). McNulty (1998) related this underachievement and failure of start up performance to the use of innovative process technology without appreciating and managing technical risk. Factors contributing to technical risk include inadequate pilot plant testing, scaled up prototype equipment without backup, design flaws and poorly understood complex process chemistry."

Jan 1, 2009

By Y. M. Chen, H. L. Zhang, W. U. Bing, C. Q. Zhou

Multiphase flow in the widely used Vanyukov furnace was numerically studied. An unsteady three-dimensional and three-phase flow model was firstly built using the computational fluid dynamics (CFD) software ANSYS FLUENT®, and then solved with the volume of fluid (VOF) and k - ??model. The results showed that the proposed model could be used to predict the multiphase movement, the slag/air fluctuation, the vortex formation, and effects of structural and operational parameters. By fast Fourier transform (FFT), the dominant frequency of density with time signal was calculated as 0.29 Hz. The analysis of different injection flow rates of enriched air indicated that this variable has a major effect on the mean slag velocity. The peak mean velocity increased from 2.17 to 4.99 m/s while the flow rate of enriched air varied from 70 to 160 m/s. The proposed model provides a method to optimize the furnace structure and operating conditions for the best furnace performance and lowest energy consumption.

Jan 1, 2015

By Glenn D. Lyle

As part of an initiative to improve value in mining, CEMI is developing a handbook on best practice in mine design. Various formats were examined, and of these, the wiki was selected as being most suitable. Being web-based, its global reach and capability of being continuously updated allows the wiki to evolve as new knowledge is generated, and to capture the diversity of experience of practitioners in the mining industry. While wikis have many advantages in terms of organizing content and searching, their ability to be edited by users is often seen as a negative characteristic for quality control. To ensure reliability of information content, author attribution, specific authorship models, and a peer review process have been implemented, in addition to the standard version tracking capability of wikis. The first phase of the project concentrates on topics related to underground hard rock mine design. The scope will be expanded to cover other aspects of mining as the project matures. Strategic partnerships with various organizations, such as the CIM, and CANMET, are being formed to provide a wide range of seed material to stimulate growth of the site. www.minedesignwiki.org

May 1, 2011

By James Westfield

Bureau of Mines activities for safety and health in the mineral industries were reorganized during the fiscal year to provide direct supervision by the Assistant Director -Health and Safety. On December 19, 1954, the field offices conducting these activities were designated as district health and safety offices reporting to the Assistant Director. The functions of determining the causes of accidents and injuries in the mineral industries and recommending measures to eliminate them were continued, with satisfactory results in improved safety records. The inspection of coal mines and enforcement of the Federal Coal Mine Safety Act of 1952 were conducted as directed by the Congress, and safety conditions in the mines were notably improved. One coal-mine explosion classed as a major disaster occurred during the year. The causes of that explosion and means for preventing a recurrence were still under investigation because of the extreme difficulty in recovering several portions of the mine. Basic research on the nature of certain hazards and ways of eliminating them is continued. Training of individual workmen and supervisors in this knowledge is a major part of the work.

Jan 1, 1956

By R. Michael Digman

Few efforts have been undertaken to date to assess the quality of mandated coal mine health and safety training for new miners and for experienced miners. This study was concerned with the quality and effectiveness of existing classroom health and safety training programs. The study involved field data collection through pre- and posttesting of trainees, audio-taping class sessions, and administering short feedback forms with trainers and trainees at 14 sites in West Virginia, Maryland, Kentucky, and Pennsylvania. Results indicate that goals, methods, materials, and outcomes of existing training programs vary widely among trainers and sites. The report provides less by way of solution to problems, than it highlights the breadth of issues that relate to the question of training effectiveness and quality. The report concludes that additional work by industry, labor, government, and academia is necessary in order to improve health and safety training programs. Recommended steps are: (a) to develop performance standards and measurable criteria in each of the types of mandated training, (b) to develop better training of trainers, (c) to develop expanded training support services. and (d) to undertake further research and development in health and safety training in the mining industry

Jan 1, 1982

By D. E. Traut

A fluidized countercurrent ion-exchange system was developed, operated, and evaluated by the U.S. Department of the Interior, Bureau of Mines. The system consisted of integrated multiple-compartment absorption and elution columns in which the solution flows were continuous except for short periods when resin increments were withdrawn. The exchange of uranyl carbonate between a simulated in situ uranium leach liquor and a strong-base ion-exchange resin together with the subsequent elution with an ammonium chloride solution was studied. The effects of the number of sections, section height, amount of resin withdrawal, solution flow rate, and column diameter were investigated. The kinetic and equilibrium relationships for the absorption and elution steps were also examined. The experimental data indicate a strong interdependence between variables. Solution retention time appears to be a major limiting variable in the absorption process, while resin residence time is the determining factor in the elution process. The column was efficient over a range of conditions, but close control was needed for optimum operation.

Jan 1, 1978

By Allen McComas, Frank Chase, Phyllip Worley

Longwall mining has gained the reputation as being the safest extraction method in underground coal mines. However, one of the most difficult tasks associated with longwall mining is moving the face once a panel is completed. Based on Mine Safety and Health Administration (MSHA) fatality reports since 1996, longwall face recovery operations have claimed the lives of 5 U.S. miners and have resulted in numerous injuries. Recovery operations can be hazardous because they involve moving large pieces of equipment in very confined spaces. They are also conducted in highly stressed ground conditions due to front abutment loads generated by panel extraction. Shield removal is the most hazardous operation during face recovery because miners are constantly exposed to the unpredictable gob edge. To protect the miners, one or more walking shields, cribbing and/or other supplemental roof and standing supports are typically employed as breaker line supports as each shield is removed. At the Harris No. 1 Mine in southern WV, mobile roof supports (MRS’s) have been used in lieu of traditional walking shields on 17 face moves since 1997. MRS’s are shield-like support units mounted on crawler tracks and are commonly used during room-and-pillar retreat mining operations. For longwall recovery, the two biggest advantages that MRS’s have over traditional walking shields are that they are remotely controlled and are highly maneuverable. MRS’s have contributed to safer shield recovery and shorter move times at the Harris No. 1 Mine. This paper will address both the safety and the operational issues associated with MRS usage during shield recovery. It will also discuss new developments, including the use of the inherently safer battery powered MRS’s, which have been recently certified by the Mine Safety and Health Administration.

By W. H. Goghill

Numerous investigators have studied grinding. Each has contributed his bit to a literature that is difficult to correlate. Too many of the results have been transformed into curves with so many "inflection points" and "counterflexures" that they obscure the issue. Some of the investigators have neglected the very essence of the problem, namely the power and the amount of material to which a known amount of work was applied. The purpose of this paper is to show the ease with which results can be interpreted when these quantities are duly recognized. Some grinding tests will be given for illustration. Grinding studies are of two kinds: (1) Study of the character of the ore and (2) study of the performance of the machines. Several ores may be crushed by a given machine, or several machines may be used on a given ore. The illustrations given in this report cover both objectives.

Jan 1, 1934

By Christopher J. Bise

INTRODUCTION Before a mine is planned in detail, a preliminary analysis is often conducted. This preplanning permits the mining engineer to make a rapid assessment as to whether or not a particular mining property warrants further consideration. In fact, a properly conducted preplanning phase can come within 10% to 20% of the actual results, thereby saving the mining engineer valuable time before committing himself to a fine-tuned analysis. The questions to be answered by mine preplanning are (1) What will be the operating conditions for the mine? and (2) How long will it take to complete the project? To answer these questions, calculations dealing with reserve estimation, production planning, man- power planning, and project scheduling are conducted. The following sections discuss these various phases of mine preplanning in greater detail. RESERVE ESTIMATION The estimation of the various characteristics of a reserve, such as quantity, grade, and thickness, is an ongoing process throughout the life of a mining venture. However, the reserve-estimation phase of mine planning is more closely associated with the preplanning phase. There are many different techniques employed in reserve estimation of solid mineral deposits; variations among them are introduced because of such considerations as ease of application or level of accuracy. In any event, each technique is developed in the following manner: (1) the mineral body is represented pictorially and then subdivided into blocks related to one or more samples of exploration data, (2) the area and volume of each block is determined, (3) the volumes are converted to representative tonnages (or, for example, grades), and (4) the results are tabulated. To illustrate this procedure, the polygonal (area-of- influence) technique will be presented due to its ease of application, flexibility in dealing with different deposits, and general acceptance. The polygonal method assumes that all characteristics of a mineral body extend halfway between a point of observation and any other point of observation. The explored portion of the mineral body is represented by polygonal prisms whose depths relate to the characteristic in question (grade, thickness, etc.) and whose plane bases relate to the area of influence of each point of observation (drill hole, etc.) as shown in Fig. 1. The polygons must be constructed in a definite order, usually clockwise and from the periphery to the center of the deposit. Table 1 can then be used to calculate the characteristics in question. Since, by definition, the polygonal method assumes that the characteristics of a mineral body extend half- way between points of observation, it becomes readily apparent that the evaluation of a vertical-drill hole exploration program requires that the sides of the polygons be formed by the intersection of perpendicular bisectors (Fig. 2). Figs. 3 and 4 show correct and incorrect construction of the polygons. The criterion for correct construction of the polygons is that all points within a particular polygon must be closer to its rallying point than those located in any other polygon. This is clearly not the case for certain points that are located in the polygon containing rallying point B in Fig. 4. Although this method can be used where the drill holes are irregularly spaced, calculations become less tedious when a square net (Fig. 5) or a chessboard (Fig. 6) grid is adopted. The numbers shown in Figs. 5 and 6 represent the relative weight for each of the shaded areas. In general, the greater the number of polygons, the more continuous the mineral body, and the more regular the grid, then the more accurate the computations will be. PRODUCTION PLANNING Before an acceptable evaluation of the production potential of a mine can be determined, a thorough exploration program should be conducted. It seems obvious that the nature and properties of the deposit and adjacent strata, the presence of impurities, and other mining conditions should be adequately determined prior to production planning and equipment selection. The lack of sufficiently detailed knowledge of the many mining parameters has led to the failure of numerous operations. For example, targeted production tonnages and equipment sizes for a coal mine are intimately related to the seam thickness. Needless to say the quality of information that is gathered from an exploration program can have a tremendous impact on the production plan. Production plans are developed initially by determining reasonable shift tonnages per operating section. Most of the time these values are developed from his-

Jan 1, 1986

By S. H. Ash

THE INVESTIGATION of barrier pillars in the Western Middle field is part of the comprehensive study of the mine-water problem in the anthra¬cite region of Pennsylvania by the Federal Bureau of Mines (1, 2, 5, 6, 7, 8,9,10,11,1,2,15,16).8 The Western Middle field is in Schuylkill, Columbia, and Northumberland Counties in eastern Pennsylvania. It has an area of 120 square miles, is 42 miles long from Delano on the east to Trevorton on the west, and is 2 to 5 miles wide. In the Western Middle field are 58 underground water pools containing 38 billion gallons of water (5). Some of the pools overflow to the surface, and the water from others seeps into adjacent mines through permeable barrier pillars separating them from abandoned mines. Several active mines are interconnected to workings in abandoned mines, which are partly filled with water. These mines are separated by barrier pillars that are considered effective only below the altitude of the connections. In some abandoned mines, pumping stations maintain the water at altitudes where the hydrostatic pressure against the barrier pillars is not excessive and does not endanger adjacent active mines. If water in these abandoned mines is allowed to rise to where it can overflow into the active mines, it must be pumped from the active mines at lower altitudes; this materially increases the cost of pumping. It is estimated that from 1944 to 1948 approximately 30 percent of the water pumped to the surface was from abandoned mines.

Jan 1, 1953

By Ralph Spickermann

UK Seabed Resources (UKSR) signed a manganese nodule exploration contract with the International Seabed Authority on 8 February 2013 for a 58,000 km2 tract on the eastern edge of the Clarion Clipperton Zone (CCZ). UKSR is a private company based in the United Kingdom and established primarily to develop the commercial potential of the CCZ deposits. This is the first of many anticipated regulatory, market and technical milestones that are requisite for (1) environmentally responsible commercial scale production of nodule derived metals and (2) generation of revenue through their sale in the global commodities market. This presentation will describe the progress made to date in this effort and an industry-based perspective on the tasks and challenges that may lie ahead.

Sep 1, 2014

By Ken Witherly

Modern airborne EM surveys typically acquire more data than is processed or analyzed at the time of acquisition Suitable additional processing can provide more diagnostic information, thereby allowing for more effective ranking and hopefully, follow-up of outcomes

Apr 1, 2005

This is the seventh in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the United States Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ The present report covering 1,875 samples represents the products of 83 companies plus those from the Pacific coast, which were averaged by the Pacific Coast Technical Group before being submitted and are published exactly as they were submitted. For the regular grade 985 samples consisting of 73 different brands are averaged. The premium grade consists of 489 samples of 40 different brands. The third grade has 401 samples averaged from 51 different brands. In this report the districts have been reduced to 21 by combining North and South Texas into one district. Fl Paso samples are reported with the South Rocky Mountain district, and Amarillo, Tex., has been included with the Middle Rocker Mountain district. In the present survey samples from Fort Smith, Ark., have been included in the Tulsa area, Indianapolis has been included in the St. Louis district. Cleveland represents the State of Ohio. Samples from Little Rock, Ark., and North Carolina have been included in the Memphis district. The Pittsburgh district includes samples only from this State and Wheeling, W. Va. The actual sampling points in each area are indicated an table 1.

Jan 1, 1939