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By P. L. Woolf

Seven evaluation tests with blast furnace iron bearing burden materials are described. The effects of pellet strength, fines in the burden, decreasing slag volume, pellet size, eliminating stone with superfluxed sinter, and eliminating stone by prefluxing the pellets were determined. Fluxed pellets and fluxed sinter made with the same ore fines were compared. The tests were conducted under cooperative agreements between the Bureau of Mines and North American steel companies. The objectives were to improve blast furnace practice, expand and develop understanding of the operation and theory, quantify the effects of changes, and explore the limitations of operability. This work was part of an extensive program of blast furnace research in experimental blast furnaces at Bruceton, PA conducted in the years 1958 to 1967.

Jan 1, 1984

By John C. Smock

The question of the proper valuation of mines of iron ore was suggested to me by the difficulties experienced in getting answers for the United States Census Office, while I was engaged in the work of collecting the statistics of mines in New Jersey and New York. The answers to the questions relating to values of real estate of mine properties varied so greatly that it was necessary to revise them according to some general principles of valuation. Generally the returns of mine proprietors seemed to be too low. There were, however, examples of what would be termed excessive valuation. The subject appeared to be of practical importance, and led to the paper here presented. The following table of selected mine statistics is given, prefacing the discussion of the principles of valuation. It is in part made up of census returns and partly of data obtained directly from mine owners and managers. The mines which were selected for the several groups and mining districts include nearly all of those from which the more full and carefully filled returns were received, and are also representative of their respective districts. Hence the averages obtained from them become good types of these groups or districts. The mines of New Jersey appear in six groups, each containing from three to eleven mines, or, in all, thirty-four mines. The magnetic iron ores of New York are in four well-marked groups, and there are twenty-six mines in them. Then follow the red hematite mines of St. Lawrence and Jefferson counties; and, lastly, the brown hematite groups of Dutchess and Columbia counties, and those of the adjacent parts of Connecticut and Massachusetts. The whole number of mines represented by the table is eighty-eight, of which twenty-eight are hematite mines. The first column gives the value of the real estate; the second that of the plant; the third is the sum of these two, or the capital invested. Then follow the number of men employed, the amount of wages paid during the census year, and the value of materials used in mining and preparing the ores for market." The seventh column gives the total expendi-

Jan 1, 1882

By G. Unland

The sizing of crushers depends on the expected crushing forces. However, the crushing forces develop differently with every individual rock while it is compressed by the working surfaces of the crusher. For sizing, this compression process has to be characterized by the maximum crushing force. The maximum crushing force depends on the strength, shape and size of the rock, the amount and velocity of the imposed displacement of the working surfaces of the crusher on the rock and the conditions of the contact surfaces. From experience it is known that the strength of the material and, therefore, the crushing forces depend on the size of the specimen. This dependence is the so called size effect. The determination is based on compression tests. The force development is recorded during the compression of the specimen and for every individual test the maximum force is determined. The occurring maximum crushing forces of several rocks with the same diameter comminuted under the same conditions can be assessed by a mean value and a variance. The relationship between the mean values of the cross section related maximum crushing forces FAmax and the corresponding sizes d of the specimens can then be described by mathematical functions. They are derived from different approaches (phenomenological, statistical and statistical-physical methods). The phenomenological methods are subjective and yield functions depending on the assumptions of a person, whereas the statistical and statistical-physical methods are based on an evaluated function and the optimization of the parameters.

Jan 1, 2014

By Dorsey Hager

NORTH -CENTRAL Texas has recently become a center of interest for the oil men of America. The bringing in of the McClosky well at Ranger, Eastland County, and the shallow pool at Brownwood, Brown County, in 1917, has stimulated interest in this area to fever pitch. Oil men from all over the United States are now investing there. The area of present interest is shown by the accompanying map (Fig. 1). The money spent in leases runs into millions of dollars. It is no exaggeration to say that a strip of country 200 miles (321 km.) long and 125 miles (201 km.) wide, comprising some 15,000,000 acres (6,070,310 ha.)., has been leased practically solid at a cost for rentals and bonuses of at least $1 per acre. The test holes contracted for will certainly number 400, at a cost of at, east $5,000,000. From what has been done in the past six months, $20,000,000 at least will be spent. To pay, returns on this amount of money, new production to the extent of at least 12,000,000 bbl. must be obtained. At present, the production from new fields will not average over 5000 bbl. per (lay; three wells at Ranger are producing 3000 bbl.; 250 wells at Brownwood produce 1000 bbl.; and the Gray well, Coleman County, is as yet an unknown factor. However, at Ranger there is every indication of developing a good pool covering from 1500 to 2000 acres (607 to 809 ha;), more or less, but the wells are deep, 3400 to 3800 ft. (1036 to 1158 m.), and cost $35,000 to $40,000 to drill. Large wells are necessary to pay for such expensive holes. As new wells are drilled, the gas pressure will be lowered rapidly, and large production need not be expected. For those oil men who expect a second Cushing or an Eldorado, Ranger holds little of promise. At Brownwood, Brown County, there are some 250 shallow wells (depths from. 200 to 350 ft.) averaging 4 to 7 bbl. per day. There is a chance of an extensive producing area, for these shallow sands to the southwest, and the opening of several thousand acres of shallow oil territory, and also some promise of deeper oil horizons in the Ranger horizon, but probably all under 2500 ft.

Jan 6, 1918

By C. A. Heiland

I. Description of reflection equipments.................. 412 A. Design features of present types.................. 412 B. Reflection equipment designed by writer.............. 418 11. Characteristics of reflection seismographs............... 421 A. Types of coupling in electromagnetic seismographs.......... 421 B. Action of pickup, amplifier and galvanometer............. 424 C. Combined action of pickups, amplifiers and oscillographs....... 433 D. Static and dynamic constants................... 434 E. Desirable values for static and dynamic constants.......... 435 111. Calibration of reflection apparatus.................. 442 A. Dynamic tests without shaking table................ 442 B. Calibration methods....................... 445 C. Various other tests........................ 451 INTRODUCTION In the past five years, the reflection method of seismic prospecting has been developed to a high degree of perfection. Its success in mapping oil structure is due to the unique and definite nature of the depth data obtained. While articles on the principle and results of this method continue to appear in increasing number, there is virtually nothing published about the instruments used in this work. Several years ago, the writer started an experimental and theoretical investigation with the object of determining which characteristics would be best adapted to the problem at hand. As a result, an equipment was developed which has proved its usefulness in a great number of field tests. W. E. Pugh, now with the Empire Oil and Refining Co., joined the writer, in 1931 and 1932, in the laboratory experiments and field tests. In 1933, a paper was written on Certain Instrument and Field Problems in Reflection Seismology, and submitted to the Institute. The part of that paper dealing with field tests was published as Contribution 34 (reprinted in this volume, p. 455). Since then, considerably more labora-

Jan 1, 1934

By Shadia Ikhmayies

ZnO microprisms in thin film form were produced by the low cost spray pyrolysis technique at a substrate temperature of 350 ± 5 °C on glass substrates. Scanning electron microscopy (SEM) and energy dispersion X-ray spectroscopy (EDS) were used to explore morphology and composition of the films respectively. The films were found to be oxygen rich and contain chlorine. ImageJ software was used to analyze the size of the prisms, where the diameter and length of the microprisms were estimated.

Mar 1, 2017

By Milton H. Fies

The dedication of thin building, establishing a station of the U.S. Bureau of vines at the University of Alabama, bristles with significance and challenges the wisdom and courage of the people of this State. Here is united, in common aim, the Engineering School of our State University, recognized for its competency and usefulness, and the Federal Bureau of Mines. The Bureau is one of the most effective arms of our National Government. It outranks in accomplishment, measured by practical scientific contribution, any like governmental organization in all the other nations. It possesses none of the characteristics of many other bureaus of government which have created popular bias. Here is one Bureau devoid of political suggestion or aim with a personnel zealously devoted to labor in scientific re¬search - an organization marked by practical accomplishment, alleviating many of life's burdens, raking easier life's pathway, and unerringly pointing to life's possibilities.

Jan 1, 1936

By Harry H. Nowlan

A heavy development campaign progressed during the year 1936 in South Texas1, following up important discoveries made in 1935. Oil and gas wells completed during the year were 1473 against 704 in 1935. The drilling program reached its peak of operations in June in consequence of offset requirements made necessary principally in Duval County in the Seven Sisters, Loma Novio, Lopez and Cole fields. There were six new fields discovered during 1936 as follows: Rhode in McMullen County; Peters, El Mesquite and North Kohler in Duval County; Wood in Starr County and Colorado in Jim Hogg County. No discovery of unusual consequence was made during the year. The pools mentioned above are simply in the primary stages of development. The most intensive exploratory work during the year was in Duval, Webb and Zapata Counties. Considerable activity also prevailed in Starr and Brooks Counties. Much significance is attached to the California Company's discovery in the Alta Mesa field in Brooks County, which is considered to be a deep-seated salt dome. The Comitas field, in Zapata County, developed some surprisingly good production in a shallow sand at 900 ft. and is being followed by a heavy wildcat campaign throughout that area in search of like production. In Starr County an active wildcat campaign is in progress in a continued effort to find new fields northwest of the Sam Fordyce field, in Hidalgo County. This play continues in a northerly direction through Starr and Jim Hogg Counties. New Fields Rhode.—The Rhode field, in southeastern McMullen County, was opened in May by the Magnolia Petroleum Co. with a gas well in the Whitsett (Upper Jackson) sand at a depth of 1810 to 1822 ft., this test is located in the southeast corner of sec. 86 on the Rhode ranch. Four gas wells have been completed, proving up a gas area of 1000 acres, more or less. Development will be slow because of lack of market for the gas.

Jan 1, 1937

By K. Osseo-Asare

Third phase formation, the separation of a solvent extraction organic phase into two liquids, is generally attributed to the limited solubility of the extracted complexes in the hydrocarbon diluents. Much of the research on third phase fomiation, therefore, emphasizes experiments designed to establish the stoichiometry of the species responsible for the limited solubility. This work offers a different approach, based on the recognition that the solvent extraction third phase, in fact, corresponds to the middle phase in a microemulsion fluid system. Using the tri-n-butylphosphate (TBP)-diluent-water-electrolyte system as a model system, current concepts of microemulsion phase behavior are utilized to develop a general framework for interpreting and predicting the patterns of phase behavior in solvent extraction systems.

Jan 1, 1999

To the members of The South African Institute of Mining and Metallurgy We have audited the annual financial statements set out on pages 239 to 245. These financial statements are the responsibility of the Institute?s Council. Our responsibility is to report on these financial statements. We have conducted our audit in accordance with generally accepted auditing standards. These standards require that we plan and perform the audit to obtain reasonable assurance that, in all material respects, fair presentation is achieved in the financial statements. The audit included an evaluation of the appropriateness of the accounting policies, an examination, on a test basis, of evidence that supports the amounts and disclosures included in the financial statements, an assessment of the reasonableness of significant estimates, and a consideration of the appropriateness of the overall financial statement presentation. We consider that our auditing procedures were appropriate in the circumstances to enable us to express our opinion presented here. In our opinion these financial statements fairly present the financial position of the Institute at30th June, 1997, and the results of its operations for the year then ended in conformity with generally accepted accounting practice.

Jan 1, 1997

By Barry Olson

The Peñasquito deposit in Mexico is one of the largest grassroots precious metal discoveries to be developed in recent years. Goldcorp Inc. acquired the gold-silver-lead-zinc property with the acquisition of Glamis in 2006. The company has since committed US$1.5 billion to construct the mine, mill and associated facilities. The first of two 50-kt/d (55,000-stpd) mill and flotation lines is currently being commissioned while engineering and construction continues on the second line. A high-pressure grinding roll (HPGR) will ultimately take total throughput to 130 kt/d (142,000 stpd). The Peñasquito property is located in the northeast corner of Zacatecas state, Mexico. The elevation of the property averages 1,900 m (6,200 ft) above sea level and it is situated in a wide east-west valley. Except for one small outcrop (Peñasquito), the area is covered by up to 30 m (98 ft) of alluvium.

Jan 1, 2009

To the members of The South African Institute of Mining and Metallurgy We have audited the annual financial statements set out on pages 269 to 276. These financial statements are the responsibility of the Institute?s Council. Our responsibility is to report on these financial statements. We have conducted our audit in accordance with generally accepted auditing standards. These standards require that we plan and perform the audit to obtain reasonable assurance that, in all material respects, fair presentation is achieved in the financial statements. The audit included an evaluation of the appropriateness of the accounting policies, an examination, on a test basis, of evidence that supports the amounts and disclosures included in the financial statements, an assessment of the reasonableness of significant estimates, and a consideration of the appropriateness of the overall financial statement presentation. We consider that our auditing procedures were appropriate in the circumstances to enable us to express our opinion presented here. In our opinion these financial statements fairly present the financial position of the Institute at 30th June, 1999, and the results of its operations for the year then ended in conformity with generally accepted accounting practice.

Jan 1, 1999

By L. B. Smith

Introduction The property of Wright-Hargreaves Mines, Limited is situated at the northeastern end of Kirkland lake, Ontario. It lies immediately east of the Lake Shore mine, and about in the centre of the Kirkland Lake camp. The district is served by the Swastika-Rouyn branch of the Temiskaming & Northern Ontario railway, the town of Kirkland Lake being four miles northeast of Swastika, which is 63 miles north of Cobalt and 392 miles north of Toronto. The mine is developed by three shafts and has more than twenty-eight miles of underground workings. There are two main producing veins, which lie in a porphyry boss 1,350 feet wide. Milling started in May, 1921, and to-date (January, 1933) the mine has produced gold to the value of $21,770,183. Present production is at the rate of 800 tons of ore per day. For a description of the geology, reference may be made to the report by E. W. Todd on the Kirkland Lake Gold Area (1). Structure and Ore Deposits The two major productive veins on the Wright-Hargreaves property are known as the North vein and the South vein. In the vicinity of the shafts these veins are approximately 550 feet apart. A third vein, known as the Inclined vein, has been worked from its junction with the South vein at the 2,000-foot level to its intersection with the North vein at the 800-foot level. This inclined vein has to date been found only in the area east of the eastern major north-south fault. The main North vein and South vein have a general vertical dip, although local rolls and post-ore faults throw certain sections out of line. From the surface to 3,900 feet, the North vein is displaced south less than 200 feet, and the South vein at the same horizon is almost perpendicularly beneath the surface showings.

Jan 1, 1934

There are available today many various types of mixing systems, tank types and process liquors confronting the process designer of gold adsorption circuits. This short paper is to give the process designer an insight into the special mixing requirements for resin-in-leach and resin-in-pulp, plus the advantages and disadvantages of the various mixing systems that are available to agitate the required tank shapes. An understanding of the latest developments in this important process area of gold production is addressed and information given on the results of resin degradation in various tank sizes over long periods of mechanical agitation.

Jan 1, 2007

By Jorge A. S. Tenorio, Pedro F. A. Prado, Denise C. R. Espinosa

There is an increasing challenge of waste management regarding the growth of photovoltaic (PV) technology. Often overlooked by its environmental benefits of greenhouse gas emission reduction, PV technology contain metals that are highly hazardous for the environment. Amorphous silicon (a-Si) PV modules employ indium-tin-oxide as transparent conductive oxide and given the high price of indium its recovery could be advantageous from an economic perspective as well. Leaching of indium was predicted by comparing the Pourbaix diagram with the values of oxidoreduction potential and pH measured on a phosphoric acid solution. The a-Si panel was subjected to thermal treatment to remove the proprietary, protective coating and allow leaching to occur. Then, indium could be leached by phosphoric acid in a jacketed reactor, reaching a concentration of 55 ppm (67% leaching rate) with a 0.2 g/mL of a-Si panel to aqueous solution ratio. The leaching of indium with phosphoric acid is novel and could open doors for many other recycling routes for solar panels.

Mar 1, 2018

By K. Gardner

"Many deposits have a geological model developed early in the project stages, which is not always reviewed or modified as the project matures and production commences. Conversely, ongoing pressures, due to a combination of declining head grades, a push for increased revenue and a multitude of other reasons, leads to processing plant modifications, with the primary aim being to increase production. Often, the ore deposit knowledge is not sustained or developed during the operational stages to the level carried out during the prefeasibility and feasibility study phases. This results in the variability within the deposit being poorly understood and a lack of data and knowledge being available to support (and ideally optimise) operations particularly in an environment where the flow sheet has changed and ore feed requirements are complex.INTRODUCTION This paper presents a case study of ore deposit knowledge development and corresponding process plant operating strategy at the Ladolam Gold Deposit, commonly referred to as the Lihir gold deposit in Papua New Guinea. The gold deposit is located in a tropical equatorial climate on the east side of Lihir Island in the New Ireland Province of Papua New Guinea. Gold mineralisation was discovered in 1982, and was followed by a major exploration campaign by a joint venture between Kennecott (Rio Tinto) and Nuigini Mining Limited. The first drillhole was drilled in 1983, and after an extensive period of drilling consisting of 343 holes for 83,500 m, the final Feasibility Study was completed in 1992. The feasibility study was based on a Reserve base of 37.9 Moz in refractory sulphide ore, with gold extraction proposed to occur via whole ore pressure oxidation due to the refractory nature of the mineralisation. The Lihir Special Mining Lease (SML) was granted in 1995 to a new PNG company – Lihir Gold Limited, and Rio Tinto established Lihir Management Company to develop and operate the mine on behalf of LGL. Mining and processing of the deposit commenced in 1997. Newcrest Mining Limited purchased Lihir Gold Limited in August 2010, and subsequently completed a major plant upgrade including the installation of additional grinding, autoclave and carbon-in-leach capacity. Post commissioning of the upgrade, Newcrest has continued to increase throughput and production. A reinvigorated ore body knowledge development program has significantly assisted this process in identifying operating strategies for the process plant and delivering recovery improvement projects to address declining head grade and recovery due to increased stockpile feed and flotation circuit use."

Jan 1, 2017

By A. Choudhury

Deep open-pit mines are becoming increasingly common in the highly mineralized arctic and sub-arctic regions. Air inversion is a frequent occurrence in these regions, and is exacerbated by the natural topography of an open-pit mine. Due to such inversions, the air quality in open-pit mines deteriorates very rapidly. Transport of gaseous pollutants under arctic air inversion is complex and involves an interaction between flow, thermal and convective transport systems. This paper discusses the construction and validation of a three-dimensional model that simulate the flow of air and the transport of gaseous contaminants in an arctic open-pit mine and the effect of low influent velocity and large gust velocities on the contaminants profiles in the mine. It was found that while higher velocities may remove contaminants from the pit bottom, they may not remove the contaminants from the pit entirely, necessitating artificial mitigation measures.

Jan 1, 2012

By A. J. Basu

New technologies, such as computer based learning, wireless computing, internet2, online courses, distance learning, and in general multimedia applications are being implemented in the higher education sector in an increasing manner. However, these implementations are not coherent, and lack standards. However, one example of the existing standards is the development and implementation of the virtual learning environments. These technology tools help in delivering the eLearning objectives. There is a major initiative in Europe (eEurope action plan) in promoting eLearning towards creating a knowledge-based society. Technology implementation is the major driver for achieving the eLearning objectives. A two-year pilot project on implementing technology tools including virtual learning environment (VLE), video-conferencing, and simulation and visualization was carried out for providing a blended learning environment for undergraduate and graduate students in Mining Engineering (undergraduate) and Mineral Deposit Evaluation (M.Sc.) course at the Imperial College London. The pilot project was funded by the Imperial College Centre for Educational Development (ICCED). The project did contribute towards activities for creating an institute-wide eLearning strategy in line with the eEurope action plan.

Jan 1, 2003

By G. S. Rice, H. P. Greenwald

"Experience and experiment have goth shown that a cloud of coal-dust in air can be inflamed and an explosion developed only when a certain minimum concentration of the dust in air has been equaled or exceeded. Those who have had experience in the handling of coal know that dust is frequently present in the air and may be of sufficient density to obscure an ordinary electric light at a distance of 40 or 50 feet; yet flames may be, and times without number have been, introduced into such clouds, when no additional coal-dust has been stirred up, with no effect other than the burning of the dust particles which actually enter flame. Evidently the density of the dust cloud is insufficient to give self-supporting combustion.The minimum amount of dust in air required to give a spreading flame will vary with a number of factors such as the composition of the dust and its size. This amount in a unit space may be considered analogous to the lower limit of inflammability of fire damp (methane) in air, although the variation in limit of explosibility of gas is small even when conditions of the experiment are altered. In large-scale determinations of the lower limit of inflammability of coal-dust there is no certain method by which a sample of the dust cloud can be snatched and its density determined. It is necessary to produce the best possible dust cloud from a known weight of dust, in a known volume and assume - probably with considerable error - that the dust cloud is reasonably uniform. The dust cloud must be formed and the source of ignition applied to it simultaneously; this is generally accomplished by the use of blow-out shots of black blasting powder, dynamite, or similar explosive so prepared as to blow out like a cannon shot, or by a gas explosion. The more violence attending the source of ignition, the greater is the probability that all the dust is raised in a uniform cloud; and the greater the length or intensity of the flame, the greater are the chances of ignition. As a result one may obtain a variation in apparent minimum density with different sources of ignition. This difference is more apparent than real and must remain until devices for instantaneous sampling of dust clouds during explosions are perfected."

Aug 1, 1931

CONTENTS PAGE THOENEN, J. R.-Limestone Production as a Mining Problem. Discussed by Oliver Bowles, J. T. Singewald, S. R. Russell 1 GRIGGS, C. C.-Engineering in Limestone Production. Discussed by W. C. Phalen, John Rice, Samuel M. Shallcross, Oliver Bowles, Nathan C. Rockwood, George Milliron 2 WILDER, FRANK A.-Rotary Calciners for Gypsum. Discussed by L. K. Arm-strong 9 PORTER, JOHN J.-Manufacturing Problems of Cement Industry. Discussed by Samuel M. Shallcross 9 KIRKHAM, VIRGIL R. D.-Phosphate Deposits of Idaho and Their Relation to the World Supply. Discussed by F. A. Wilder, S. L. Willis, G. R. Mansfield, R. W. Stone, L. K. Armstrong 9 Limestone Production as a Mining Problem Discussion of the paper of J. R. THOENEN, presented at the New York Meeting, February, 1925, and issued, as Paper 1417-H, with MINING AND METALLURGY, February, 1925. OLIVER BOWLES, New Brunswick, N. J.-I am so thoroughly convinced of the growing importance of underground work in the production of limestone that I had the author make a detailed study of limestone mining for the Bureau of Mines and prepare a report on the principles of limestone mining. Many limestone operators, long accustomed to open¬pit work, are being forced to mining. About 6 months ago I thought there were twenty-five or thirty underground limestone operations in the United States but the author has been finding new ones until his list now runs nearer sixty. Some of these are very extensive; one at least has 4 ½ miles of underground workings. There is an ever-expanding field for the engineer in the operation of limestone mines and quarries. Some of the larger companies realize the need of skilled engineering advice, but many of the companies regard the engineer as an unnecessary expense. Although almost every metal mine, even those handling only a few hundred tons of ore per month, employs a mining engineer, many limestone operations ten times as large employ no mining engineers. Few mining engineers are at all familiar

Jan 6, 1925