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By Frank B. Fulkerson

Aluminum production in the Pacific Northwest has a new potential for expansion and increased stability of operation. This new potential results from greater availability of power; lower freight rates on alumina and aluminum; good market prospects for the metal, including western aluminum market expansion following a decline in defense requirements in the 1950's; and possibility of developing bauxite deposits in the Pacific Basin as well as other mineral resources. INTRODUCTION This is a report of a special study by the Bureau of Mines of the primary aluminum industry of the Pacific Northwest. It outlines developments relative to the United States as a whole.

Jan 1, 1962

By A. Bascetin

One very important aspect of mining is deciding what material in a deposit is worth mining and processing, versus what material should be considered waste. This decision is summarized by the cut-off grade policy. The cut-off grade strategy for an open pit mine influences the annual cash flows and affects the net present value of a project. The optimization of cut-off grade strategy requires the knowledge of detailed operational costs, mining sequence, mining operation, processing, and product constraints, as well as the grade distribution of a given deposit defined by pit, phase, and different material types. Cut-off grade optimization algorithms have been developed in the past. The most common criteria used in cut-off grade optimization is to maximize the net present value (NPV). This paper describes the determination of a cut-off grade strategy based on Lane?s algorithm adding an optimization factor based on the generalized reduced gradient (GRG) algorithm to maximize the project?s NPV. The introduced algorithm is a windows based program developed at Virginia Tech that is based on a series of Visual Basic routines within a spreadsheet environment (Excel).The benefits of the methodology are demonstrated using a hypothetical case study. Keywords: Cut-off grade optimization, net present value maximization, generalized reduced gradient algorithm method.

Jan 1, 2007

By Edward J. McNamara

People in the real estate industry are fond of saying that the three most important features of a piece of property are, in order, location, location, and location. This is perhaps the reason that the owners of a well known high-end restaurant chain chose to spend $15 million dollars to renovate 5000 square feet of basement in a 22-story commercial building in the heart of New York City's Time Square. The goal was to create a music club with a stage area and dance floor with a mezzanine level surrounding the dance floor. In order to create the 50' x 40' dance floor and 20' x 40' stage area, 3 concrete columns were removed. New transfer girders were used to transfer the loads of these columns to new steel columns. For the mezzanine, nine columns had to be underpinned. All work continued while the restaurants, shops and offices above carried on business as usual. This paper details some of the means and methods utilized as well as the challenges faced by Underpinning & Foundation Constructors, Inc. in underpinning the columns and installing the new transfer steel.

Jan 1, 2000

By Roger Frank

"Abstract After noting the importance of standardization for piles, the European system is described (execution, tests and design, etc.). Some important aspects of Eurocode 7 are outlined (like the role of pile load tests). Finally, the calculation methods in the recent French standard for the design of piles following Eurocode 7 are shortly addressed.Importance of standardization for piles Like for other fields of geotechnical engineering, pile engineering is a complex art. For piles, the challenges are particularly numerous and many things must be mastered properly: - the soil investigation must be serious and adequate (for instance, deep enough!);- the choice of the pile type and the assumed behaviour must be assessed in order to reach a safe and economic design of the overall foundation;- the execution itself (construction and/or installation) deserves special attention and must follow strict state-of-the art rules.The geotechnical engineer, in charge of the design of a pile foundation, must have in mind the parameters linked to the variety of soils, of soil conditions and of pile types. A wide range of strong environmental issues are also to be considered: minimum disturbance during the execution processes, long-duration friendliness of the “inclusions” into the ground (to avoid pollution of the soils and waters, for instance) and respect of the neighbouring structures.Pile engineering plays in a world which is constantly moving and progressing: constructions expand in new difficult areas, actions on piles are more and more important, new execution techniques of piles are developed, research into the complex behaviour of pile foundations has no end, etc. Our views on how piles and group of piles really work are constantly evolving!"

Jan 1, 2014

By Chas. F. Jackson

During the current business depression the Bureau of Mines has received many inquiries concerning placer mining, the prospects for men of small means to make wages by small-scale placer operations, the locations of placer deposits in the United States, methods of working placers on a small scale, and allied subjects. It has therefore seemed desirable to prepare a circular covering, in nontechnical language, the principal questions which have boon referred to the Bureau of Mines for answer. There are a number of bureau publications dealing with placer mining, most of which are now out of print, but which may be consulted in the larger libraries. Other articles on placer mining nave appeared from time to time in the technical press and several good textbooks have been written on the subject. A partial bibliography of this literature appears at the end of this paper. A recent pamphlet published by the Idaho Bureau of Mines and Geology to assist the prospector and inexperienced small operator has received wide and favorable attention and is recommended as a useful reference. In the present paper no attempt will be made to cover the subject of placer mining in a comprehensive manner, but discussion will be confined to elementary questions of particular interest to persons of limited experience.

Jan 1, 1932

By L. A. Morley

This report summarizes the work performed on Bureau of Mines Contract J0199106, "Portable Trailing Cables, Splices, and Couplers - Design and Installation Considerations," from May 1, 1979 until December 31, 1981. Splice installations and considerations for the possible use of conductive-rubber shielding in low-voltage trailing cables as well as coupler installations in high-voltage cables were the principal tasks. Flammability measurements on cable components and general testing facilities for mine electrical equipment were secondary tasks. Theoretical and empirical data indicate that conductive rubber with high resistivity values is an unsatisfactory shield design for current-sensing fault detection. Elimination of partial discharge in coupler installations requires meticulous care.

Jan 1, 1982

By O. W. Shimer, D. C. Helms, C. E. Brown

The early history and progress of anthracite stripping, from the first known operation at Summit Hill in 1821 through 1917, was covered in 1917 in a paper by J. B. Warriner,1 then chief engineer, now president of the Lehigh Navigation Coal Co., and stripping methods between 1917 and 1931 were the subject of a paper in 1931 by H. H. Otto,2 of the Hudson Coal Company. The present paper is confined to methods used today on pitching beds in the western middle and southern anthracite fields. The anthracite industry, not unlike other large industries, had been affected for more than a decade by the adverse economic conditions of the country. High development and operating costs and the competition of other fuels caused some collieries to be closed temporarily, while others were permanently abandoned. In order to obtain a larger tonnage at a lower development cost, a larger stripping program was put into effect by many companies. In 1932, stripping operations accounted for 3½ million tons, or 7 per cent of the total anthracite production of the year, and in the next 10 years this increased until more than double that amount, or over 14 per cent of the total production, was from stripping operations. These figures represent the total production of the entire anthracite region; unfortunately, the figures have not been separated from the different fields. There are some operations in the southern and middle western fields where the tonnage obtained from stripping amounts to more than 30 per cent of the total colliery production. Stripping operations on pitching beds present difficult problems. Owing to the various geological formations, a different situation is encountered in nearly every stripping pit; and because of the proximity of an overlying bed, it is very often necessary to load the entire overburden into trucks and haul it out of the pit to the dump area, although back filling and casting is done whenever possible. Beds in the areas described in this paper pitch from 20" to 90° and some are on the invert in many sharp folds and faults. Planning The more successful strippings have had adequate engineering analysis. Some work is being done without much preliminary planning, but many strippings would have failed completely if close supervision by the engineering department had not been maintained. Locations of stripping areas are determined as follows: I. By constructing cross sections over the areas and drilling sufficient diamond-drill or well drill holes to study the strata and to determine the location, thickness and pitch of the beds.

Jan 1, 1946

By George J. Simchuk

The selection of a stripping method and subsequently, the stripping equipment, are two of the most important decisions confronting a project engineering staff during the initial feasibility study of a new coal stripping operation. The selected stripping units average from 60 to 70 percent of the total capital outlay for mine equipment and their selection will affect the type, size, and quantity of the attendant equipment, such as loading shovels, drills, haulage trucks, and bulldozers. This paper is intended to report on an in depth study by Utah's Technical Services Staff regarding the selection of stripping equipment for the Goonyella Coal Mine in Queensland, Australia. We will touch briefly, on the objectives considered in this selection; the various alternatives which were explored; the general assumptions that were followed throughout the engineering and design of an appropriate stripping system; and computations necessary to determine the amount and size of stripping equipment. INITIAL EXPLORATION Utah Development Company (presently 90% owned by Utah Construction & Mining Co. and 10% by Australian investors) commenced systematic geological studies of the Bowen Basin coal fields of Central Queensland in 1961. The Blackwater Mine as shown in Figure 1 has since been established in this area and is now producing 3.0 million tons per annum of washed coking coal. Geological reconnaissance was then extended to the northern part of the Bowen Basin and in 1963 Utah's coal prospecting area covered 2444 square miles of Central Queensland. The authority to prospect north of Blackwater has since been trimmed to 810 square miles by relinquishments to the State.

Jan 1, 1971

By D. J. Reddish

An understanding of the mechanisms that cause large seismic events in a deep mine provides a foundation for designing effective measures to reduce the incidence of these events, as well as reduce the potential for damage arising from these events. The work described in this paper focuses analytical efforts on major recognizable and controllable factors that influence mining-induced seismicity and serves to screen out many of the more random aspects of individual events. Information used in this study was developed in the course of a long-standing rock burst research program conducted by the U. S. Bureau of Mines in cooperation with mines in the Coeur d'Alene Mining District and regional universities. Information was collected on 39 seismic events having local magnitudes greater than 2.5 that occurred between 1989 and 1994. Five major types of events were developed from these data that describe all but two of the 39 large events. The characteristic mechanisms, tint-motion pattern, damage pattern, and relationships to mining and major geologic structures were defined for each type of event. This information provides a foundation for assessing whether or not changes in mining activity aimed at reducing one type of rock burst will increase the incidence of other types.

Jan 1, 1996

There are circumstances where the ordinary techniques of experimental variography in geostatistics û now in common use despite their recent origin û are not quite successful. This paper describes a new addition to the geostatisticians tool kit developed by one of the renowned leaders in the field to cope specifically with these circumstances. Possible application of this technique will be outlined when it will be seen that there are still problems remaining to be solved in its use for economic evaluation of deposits with irregular mineralisation.

Jan 1, 1984

It is a great honour to be privileged to address The Institute for a second time as President and I appreciate it more than I can say. Eight years ago in Hobart I tried to cover the development of the mineral industry in Tasmania. That was a general subject. Tonight I want to be more specific - I propose to talk to you about rutile.The choice of subject for a Presidential Address is never easy. One is addressing an informed audience and the best one can do is to try to crystallize a particular subject and to present it in a form that willbe of interest to those who listen.I looked carefully at the addresses given by our Presidents over the past seven or eight years. The titles are impressive, the content excellent, and the length, as published, much greater than I had hoped.It is therefore with some trepidation that I have chosen as a subject one only of the three crystal forms of titanium dioxide. This subject is not as limited as may at first appear.There are two aspects with which I can deal - the mineral itself, which has become familiar as the major product of the East Coast beach sand operations, and the lesser-known "synthetic" product, which is the major pigment in almost all the white paints in common use today, and in cosmetics and white-walled tyres and toothpaste, and even the better types of fine papers. The synthetic form of rutile is' the "whitest"of white pigments.

Jan 1, 1966

By Francis X. Cannaday

Equipment and techniques were developed with Bureau of Mines facilities for measurement in the laboratory of sonic shear wave velocity in variously shaped rock specimens in a wide range of sizes. A variety of rock types was tested. The shear wave front is produced by electronically excited, piezo-electric ceramic) disk-shaped transducers. Transmitter and receiver are interchangeable. Special equipment components were Bureau produced; other components were commercially available. The equipment permits quick measurement of shear wave velocity on variously shaped specimens with a minimum of specimen preparation. The technique, under favorable conditions, allows for determination of the moment of arrival of the shear wave when it is superimposed on a weak longitudinal wave.

Jan 1, 1968

By T. N. Williamson

Most U.S. coal production is bituminous coal. Some 90% of current production comes from a geographical area enclosed in a circle with a 300 mile radius and its center at about Huntington, West Virginia. There are important underground coal production areas in the western parts of the United States as well. Most U.S. coal production comes from fairly level seams, many of which pitch rather uniformly only a few feet per mile. Usually there will be several overlying seams of varying thicknesses, separated by several tens of feet. Fig. 1. 1. Seams have minor local undulations but these? are small enough not to be a major consideration in a horizontal drilling research program.

Jan 1, 1970

By Wilbert J. Huff

This is the sixth of a series of annual reports describing the work of the? Explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with the activities of the division from July 1, 1940, to June 30, 1941. The studies outlined in this and preceding reports of the series have been conducted under the direction of the author and the respective unit leaders, to whom specific credit is given.

Jan 1, 1942

By Wilbert J. Huff

This is the sixth of a series of annual reports describing the work of the Explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with the activities of the division from July 1, 1940 to June 30, 1941. The studies outlined in this and preceding reports of the series have been conducted under the direction of the author and the respective unit leaders, to whom specific credit is given.

Jan 1, 1942

By R J. Holmes

An accurate knowledge of the chemical, mineralogical and physical characteristics of ores and mineral products that are mined, processed and traded is crucial to effective resource utilisation, plant design, process optimisation and finally quality control to ensure that contract specifications are met. However, all too often the responsibility for sampling is entrusted to managers and personnel who do not fully appreciate the significance and importance of collecting representative samples for analysis, and everyone seems satisfied as long as some material is collected and returned to the laboratory for analysis. Furthermore, sample stations incorporated into the design of new plants are often the first casualties when cost cutting exercises commence. This needs to change, because there is little point in accurately analysing samples if they are not representative in the first place. The resultant analyses can be next to meaningless and the effort taken to analyse such samples is to a large extent a waste of time and resources.Ultimately, a poor knowledge of the characteristics of ores and mineral products limits the ability of mining companies to optimise the life of ore resources and plant performance, and failure to meet final product specifications can have disastrous consequences, including price penalties and more seriously loss of sales contracts. It is high time that sampling is given the attention it deserves as the first critical step in the quality measurement chain.CITATION:Holmes, R J, 2013. The importance of sampling in the mineral industry, in Proceedings MetPlant 2013 , pp 34-49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Becerra J. O

HYL developed a direct reduction process (DR) that does not require a reformer; it is called self-reforming process. Typically, direct reduction processes based on natural gas utilise a reformer unit to transform the natural gas into reducing agents (hydrogen and carbon monoxide). The reforming reactions are: CH4+H20-?3H2+CO CH4 + CO2 - 2H2 + 2CO These reforming units require a catalyst agent to promote the kinetics of the reforming reactions. The catalyst for these reactions is typically a metallic element such as nickel in a ceramic matrix; iron is also an excellent catalyst for the reforming reactions.

Jan 1, 1999

From Sept. 22-24, the Las Vegas Convention Center will be home to MinExpo 2008, the world?s largest mining equipment show that comes along once every four years. Sponsored by the National Mining Association (NMA), this year?s show is on pace to be the largest ever. Nearly 1,300 exhibitors have purchased nearly 55,700 hm2 (600,000 sq ft) of booth space. At the center of it all will be some of the most impressive mining equipment that the industry has to offer. And in the shadows of the massive haul trucks, drill rigs and bulldozers, attendees will be able to see the latest and greatest products including hand tools; the latest in automation and robotics; safety and communications equipment; longwall mining equipment; engines and parts; materials handling and processing equipment and services; pollution control equipment; reclamation equipment and services; computer applications; consulting and financial services and more. While many companies will be on hand to display the tried and true, there will also be plenty of new things to see. ?We anticipate that a whole range of new products will be introduced at the show,? the NMA said of the show that has been called the world?s richest deposit of mining technology, services and products. In addition to the show that will take place in Center Hall and North Hall of the Las Vegas Convention Center, MinExpo 2008 includes a conference program with 20 educational sessions that will tackle the most timely and pressing issues affecting the mining industry. Many of the industry?s top professionals will lead the discussions.

Jan 1, 2008

By Robert L. Parsons

This paper describes the results of a detailed analysis of a loess deposit at the deep foundations test site established by the Kansas Department of Transportation. Multiple CPT, SPT, and pressuremeter tests were conducted as part of the investigation. This paper includes an evaluation of the effectiveness of common correlations used with the CPT, SPT when used for classification of loess and estimating its properties. Results show that common correlations must be used with caution as significant errors in estimation may result from using methods developed for other soil types. Laboratory testing included direct shear, triaxial, collapse, and consolidation testing, with many of the tests conducted on both vertically and horizontally oriented samples to evaluate anisotropic behavior. The results showed that strength properties could be considered to be isotropic.

Jan 1, 2009

By AIME AIME

The Bulletin. As already announced in the January Bulletin, this publication will be issued during the coming year monthly instead of bi-monthly as heretofore. Among other reasons for this change, it is desired to effect thereby the earlier transmission to members of important papers, lists of candidates for membership, and other items of timely information. The New Haven Meeting. As already announced in special circular, the XCVIth meeting of the Institute for the reading and discussion of papers will be held at New Haven, Conn., beginning Feb. 23, 1909. The Secretary of the Local Committee is Prof. J. D. Irving, Box D, Yale Station, New Haven. The program embraces visits to many interesting works in New Haven, Ansonia, Bridgeport, etc. The leading topics for discussion at the sessions will be: The Conservation of Natural Resources; A Sea-Level Canal at Panama; and The Technical Education of Mining Engineers. But papers on other subjects also are announced. A supplementary session of this meeting will be held in New York City, at some time during March, 1909, as a joint session with other national engineering societies, for the further discussion of the subject of The Conservation of Natural Resources. A Pacific Coast Meeting. The XCVIIth meeting will be held on the Pacific Coast, including a visit to the Exposition at Seattle, and various other points en route going or coming, depending upon the route and program finally adopted. More definite information will be announced at the New Haven Meeting, or at the earliest possible date thereafter.

Feb 1, 1909