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By Ramarao Inguva

Feasibility studies being conducted to investigate the use of electromagnetic methods for insitu volumetric heating of oil shales will be discussed. A two dimensional numerical model which describes eletromagnetic heating of oil shales is outlines. The model includes equations for temperature, pressure, saturations, chemical reactions, mass conservation, and source terms. The gases are all assumed to form one bulk species and the oil is assumed to remain in liquid form. The chemical reactions include pryolysis of kerogen and char, release of bound water, coking, and decomposition if carbonates. Porosity and permeability are dynamic functions of the organic materials. Calibration of the model is accomplished by comparison of the model results with experimental data obtained by IITRI. Nonlinear relationships for viscosity, thermal properties, and source terms and used as inputs to the model. A finite difference approximation to the differential equations is derived and solved using Newton's iteration technique. For the cases studied the solutions are quite stable. Numerical resultes are included and a preliminary study of the optimization of the heating process is presented.

Jan 1, 1984

By John S. Livermore

I feel very privileged to be added to the distinguished group that has received this award since the first recipient, Reno Sales, received it in 1954. If my research is correct, the last geologist to be honored was Bill Callahan in 1982. Perhaps the Awards Committee decided it was about time to select a geologist, and I became the beneficiary. Regarding the discovery of the Carlin ore body, it was the culmination of several studies - one going back as far as 1939 when a US Bureau of Mines engineer named W.O. Vanderberg recognized an unusual type of gold mineralization in sediments in northern Nevada. What was unusual was the fact that the gold was so fine that it would not concentrate in a pan. This, plus the study of the Roberts Mountain thrust by Ralph Roberts (1960) and conversations with Harry Bishop, manager of the Gold Acres Mine, pointed Alan Coope and me in the direction of the Lynn Window and, eventually, the Carlin discovery. There has been a great deal written about this discovery. I thought it would be interesting to discuss the evolution of Carlin gold exploration in Nevada since this time and to discuss the changes in perception of this unique type of mineralization. The method used by Coope and me in following up on Roberts' work was to map geologically the Roberts Mountain thrust and conduct geochemical sampling of favorable outcrops and float. Coope was highly experienced in geochemical exploration, as he had graduated from the Royal School of Mines in London, studying under John S. Webb, one of the pioneers of geochemistry as applied to mineral exploration. We first considered using pathfinder elements, but finally concentrated on gold analyses alone, even though the sensitivity of fire assays used at that time was only about one-half part per million. According to the spatial relationship of the mineralization to the Roberts Mountain thrust, as pointed out by Roberts (1960), we were looking for mineralization within the thrust itself. Our models were the known Gold Acres and Getchell mines, which contained reserves on the order of 0.9 to 1.8 mt (1 to 2 million st). These were not of substantial size, but I had hoped we might find more than one of these tributary to a mill that would justify an operation for our employer, Newmont Mining Corp. What we ended up with was the type of deposit we were looking for - an open pit deposit of micron gold, which the old timers had missed because the gold was not capable of being panned. But never in our wildest dreams did we think there was a chance of finding a body containing 10 mt (11 million st) of ore at 0.30 oz/st (10.3 g/t).The deposit was not in the thrust proper but was found in a favorable horizon of Roberts Mountain siltstone that was below the thrust. This is the first example of how a model should not be followed blindly. Newmont was successful in keeping this discovery quiet for some time. After a considerable amount of drilling, a rumor circulated that they had discovered a large low-grade ore body of around 1.7 to 2.1 g/t (0.05 to 0.06 oz/st), which of course would not have been economic with gold at $1.13/g ($35/oz), which was the fixed price at that time. The company, for obvious reasons, did not discourage the rumor. When, however, the true results came out there was a lot of feverish activity. Because of this new type of so-called "invisible gold," which could have been missed by the old timers, the thought was that other deposits would be discovered very soon. The Carlin and other smaller deposits, including Bootstrap, Blue Star and Gold Quarry, were in windows where the lower plate of the Roberts Mountain formation (below the thrust) had been exposed by erosion. This then became the new

Jan 1, 1997

By Tsutomu Yanagase

Non-ferrous smelting industry in Japan often had the severe problems about the over production of sulfuric acid. There has been such a closed relation between amount of sulfuric acid from non-ferrous smelting industry and the products of copper, zinc and lead metals that the production of one ton of copper accompanies three tons of H2S04. When the proper balance exists in both markets this situation certainly brings bigger profits. In Xining and Metallurgical Institute of Japan the research commitee concerned with the fixation process of sulfur in non-ferrous smelting industry was established in 1977 and continued the activity for four years untill 1981. This paper will introduce some of the activities involved in the report published by the committee.

Jan 1, 1982

By R. S. Shepard

A quick glance at a-portion of the title of this discussion -'Rolling With The Punch" may immediately lead you to assume that I am about to expound on the so-called manly art of self-defense. So that you will not have been misled entirely we will devote our considerations to a far more important art and if I may, I should like to begin by quoting Vincent Van Gogh. According to a literal translation the artist in describing one of his famous paintings said "these peasants are eating their potatoes with those very hands that dug them from the earth' and put them in the dish". Vincent Van Gogh may not have realized at that time, that he could likewise have been describing what is probably one of the oldest of all arts - the art of Material Handling - an art that man with the aid of science has tried to improve since the beginning of time.

Jan 1, 1963

By D. A. Gulley, L. J. MacDonnell, William A. Vogely

INTRODUCTION Environmental impacts are most commonly associated with air and water pollution. Not- withstanding this fact, to many people the primary disruption caused by mineral extraction is the change in the character of the locale. That is, the environmental impact of mining includes, but is not limited to, the generation of residuals. The dramatic transformation of wilderness or rural land often creates strong reactions to mineral development. Thus, the basic issues of land use management are a useful addition to environmental discussion. In this section, we take up a discussion of federal, state, and local land use management regimes, along with a brief introduction to the potential role of economic analysis. Elsewhere in this volume, land management issues are discussed from other orientations, and the interested reader may wish to look there as well. Locatable Minerals on Federal Lands Legislation and Administration: Access to hard-rock minerals on the public lands is governed by the General Mining Law of 1872. This law declares that "valuable mineral deposits in land belonging to the United States . . . are hereby declared to be free and open to exploration and purchase . . . ." In order to initiate rights, prospectors are required to physically stake claims of specified sizes and shapes following basic procedures set by federal law which may be supplemented by the individual states. Rights to these claims are protected at the exploration stage so long as actual possession is maintained and diligent exploration activity is underway. If a valuable mineral deposit is discovered on the claim, the claimholder earns the exclusive right of possession as against private parties so long as the claim is properly maintained. To maintain this exclusive right the claimholder must per- form $100 worth of labor or improvements, known as assessment work, on each claim every year and make related annual filings with the U. S. Department of the Interior. If the existence of a valuable mineral deposit can be demonstrated, and other legal requirements are met, the claimholder may receive a patent giving full title to the claimed land, including the surface in most cases. The purchase price is either $2.50 or $5 .OO per acre. The Mining Law has remained largely un- changed by legislative amendment during its now more than 100-vear existence. However, while the law itself has not changed, its interpretation and administration have changed considerably. Written at a time of rapid western expansion of the U.S. following the Civil War, the intent of the law was to promote mineral development by inviting unrestricted prospecting and by selling the lands containing mineral deposits at a minimal charge. As federal land policy shifted from one of rapid disposal into private ownership to one of retention and management for a number of uses, mineral patenting requirements have been administered more strictly. The most critical issue concerns what must be demonstrated to establish the existence of a valuable mineral deposit. The so-called "prudent man" standard was established in the case of Castle v. Womble (19 L.D. 455 (1894)):

Jan 1, 1985

By Jan Jekielek

Increasing capacity of bulk material handling systems creates difficult problems for accurate in-line material weight measurements. At the same time increasing system complexity and growing user demands call for more measurements. Precision in-line weight measurements for bulk materials are usually accomplished by application of conveyor belt scales. Belt scale accuracies listed by scale vendors are applicable for ideal situations with suitable conveyor design, belt scale location and calibration means. This paper attempts to provide designers and users with simple means to evaluate belt scale accuracy for practical scale installations. Based on known mathematical models simplified formulas for measurement errors are derived and discussed. These formulas allow for simple determination of achievable accuracy for alternative scale installations on the conveyor, conveyor designs, etc.

Jan 1, 1979

By A. J. Erickson

In mid 1970, Park City Ventures, a Utah partnership of ASARCO and TAC, initiated a six phase exploration and development program in the Park City District, Utah. Geologic studies had delineated a number of exploration tar¬gets in several areas of the district. Discovery of ore in any of the target areas and continued favorable down dip development below then productive ore bodies would allow for reserve expansion and mill construction. The targets were: Mississippian Humbug Formation replacement mineralization below productive ore bodies on the east flank of the Park City Anticline; Humbug replacement mineralization in an unexplored fault block in the footwall of the Hawkeye structure on the east flank of the anticline; vein and replacement mineralization along the Silver Fissure; potentially higher grade Humbug replacement mineralization in a theorized structural block on the west flank of the anticline beneath the Ontario Vein; Permian Park City Formation replacement mineralization in the West End Shaft Area of the Silver King mine; vein mineralization along the Back Vein in the Judge Mine. Chilean Nationalization in 1971 resulted in a 30% budget cutback. The Judge and Silver King Projects were suspended. In spite of the cutback additional reserves were developed below the Humbug East Flank ore bodies; a major zone of ore grade mineralization was discovered along the Silver Fissure; five new ore bodies were found in the Humbug, and Doughnut Formations on the west flank of the anticline beneath the Ontario Vein. First concentrates were shipped from a new mill in May 1975.

Jan 1, 1976

By Mahmud Esad Uluer, Aaron Noble

Respirable coal mine dust (RCMD) is one of the biggest occupational health hazards for underground coal miners. Coal extraction is a main source of RCMD. To prevent challenges related to RCMD from developing, it is vitally important to limit airborne RCMD and stay within the regulatory limitations for mine operators. The flooded-bed dust scrubber (FBS), mounted on a continuous miner, is one of the most widely used dust mitigation technologies in room-and-pillar mining, but it is limited by technical challenges, the most notably being the potential to clog. In this study, the impact of mesh design and surface modification on system efficiency is examined using different vibrating, liquid-coated, stainlesssteel mesh panels in a laboratory-scale FBS.

Sep 1, 2024

By Richard H. Olson

The following discussion will deal with the domestic talc industry only, inasmuch as the writer has had no experience in this field outside of the U. S. This is strictly a geological-mining approach; no attempt is made to assess in depth the effects which milling technology and marketing capability might have in determining the potential of any given talc deposit.

Jan 1, 1970

By Karen M. Kessen

The isotopic variations of lead from Mississippi Valley galenas have long been used to place constraints on the sources of the lead, and on the residence the of the lead in crustal reservoirs prior to its emplacement in the Mississippi Valley province. Similar studies based on strontium isotope variations in gangue minerals associated with the lead-zinc sulphides have been neglected until Haden's (1) study of such minerals from several localities in northwestern Ohio. His work revealed two things about the mineralization. Firstly, it shoved that the average isotope composition of lead from galenas from northwestern Ohio lies on the anamalous lead line characterizing Mississippi Valley-type leads, albeit at the least radiogenic end of the entire data array. This confirm earlier assignments of the Ohio mineralization as Mississippi Valley-type (Hey1 and others (2)). Secondly, Haden (I) showed that the strontium in the calcite, strontianite and fluorite is broadly similar in isotopic composition to the strontium in the host Silurian to Devonian marine carbonates within which these minerals arc emplaced. He concluded that the mineral strontium my have been very locally derived, from the carbonate hosts.

Jan 1, 1979

The process design of a metallurgical plant follows logical steps, one built on another, to define the circuit requirements. The methodology used and documentation produced is the same for a pre-feasibility study, feasibility study or a complete design, regardless of the process complexity or the commodity. The only difference is the amount of detail developed at each stage. SRK Consulting, an independent, international consulting practice that provides focused advice and solutions to clients, mainly from earth and water resource industries, has consulted on many mining projects around the world. The company was formed in 1974 and now employs more than 1,600 professionals in more than 50 offices on six continents. According to SRK experts, the first element in plant design is collecting metallurgical testwork or operating data from an existing plant. The testwork identifies the process, the metallurgical recoveries and product qualities and establishes the process parameters for economic recovery of the commodity. Test samples must represent both the whole orebody and the feed over the life of the mine, showing the mineral?s variability. With this data available, the process design can be developed.

May 1, 2013

By Toyohisa Fujita, Mitsuo Mamiya, W. Tai Yen, Hiroki Kogita

Green algae taken from an acidic mine drainage and blue-green algae taken from an alkaline hot spring stream were collected and tested for their ability to recover or remove dilute metal ions. Experimental results demonstrated that unwashed blue-green algae and washed green algae effectively adsorbed base metals ions and eluted them at pH 1. It was also found that washed and dried algae adsorbed precious metal ions more effectively than unwashed algae. For example, the washed and dried blue-green algae was capable of adsorbing 0.31 kg of gold per kg of algae. The gold from tetrachloroaurate solution which was adsorbed on washed blue- green algae was found to change to a metallic state following initial metal binding. In the case of a dilute gold complex solution leached with thiourea, only a small amount of gold could be captured by algae. Further experiments were conducted on components of the algae, such as alginic acid, agar, cellulose and chitin and mixtures of these components, in order to determine their contribution to metal adsorption characteristics. However, a mixture of these two components demonstrated both good adsorption and desorption characteristics indicating an interaction between the individual components.

Jan 1, 1995

By John D. Shaw

1. Introduction 2. The Hydraulic Mine _ (i ) Development (i i ) Extraction ( i i i ) Transport 3. The Water Circuit 4. Manpower and Results 5. Modifications 6. Conclusions 1. Introduction The Kaiser Resources Ltd. hydraulic coal mine is located in south eastern British Columbia, Canada, at the western end of the Crowsnest Pass, next to the Town of Sparwood. The seam presently being mined is the number 10, known locally as the Balmer seam, which is a high quality coking coal, 50 feet in thickness and of an average inclination of 35 degrees. The mine was designed in the late sixties as a small scale trial unit, and was to use a single monitor unit, working 3 shifts per day on a 5 day per week basis. Experience has proved the method to be so successful as to warrant the expansion of the ancilliary facilities to cater for the increased production. The annual raw coal production from this single monitor unit has risen from 108,988 short tons in 1970 to 942,334 short tons in 1975, with a total mine labour force of about 160 men including the surface de-watering plant, mine supervision and mine administration.

Jan 1, 1977

By K. A. Natarajan, Abha Kumari

In this paper, electroleaching and electrobioleaching of ocean manganese nodules are discussed along with the role of galvanic interactions in bioleaching. Polarization studies using a manganese nodule slurry electrode system indicated that the maximum dissolution of iron and manganese due to electrochemical reduction occurred at negative DC potentials of -600 and -1,400 mV(SCE). Electroleaching and electrobioleaching of ocean manganese nodules in the presence of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans at the above negative applied DC potentials resulted insignificant dissolution of copper, nickel and cobalt in IMH2S04 and in sulfuric acid solution at pH 0.5 and 2.0. Mechanisms involved in electrobioleaching of ocean manganese nodules are discussed. Galvanic leaching of ocean manganese nodules in the presence of externally added pyrite and pyrolusite for enhancement of dissolution was also studied. Various electrochemical and biochemical parameters were optimized, and the electroleaching and galvanic processes thus developed are shown to yield almost complete dissolution of all metal values. This electrobioleaching process developed in the laboratory may be cost effective, energy efficient and environmentally friendly. Keywords: Ocean manganese nodules, Electroleaching, Electrobioleaching, Galvanic interactions

Jan 1, 2003

By Donald Towse

Portland cement is a basic building material in every country in the world, and, fortunately, the raw materials required in its manufacture are widely distributed. It is a low-priced bulk commodity (price one cent a pound or less, with a density of 100 pounds per cubic foot.) Table 1. Approximate price per pound of selected mineral products. Copper 48 cents per pound Aluminum 27 Lead and zinc 15 Asbestos 3 to 18 Pumice 6 Sulfur 2 Bauxite (abrasive) 1.8 Barite 1 to 1.6 Cement 1 Primitive regions may get along without any Portland cement, but most countries use some, and it is one of the most widespread building materials, even if used in small quantities. Use of cement begins early in a country's development, and, because of local availability of raw materials, cement manufacture is one of the first heavy industries many countries desire. Use and manufacture of cement usually precedes other industrial materials such as steel and heavy chemicals, and consumption levels off for a long period during development of infrastructure and an economic base. With a mature economy comes a very high consumption. Per capita consumption varies ten times or more between nations (Figure 1).

Jan 1, 1970

By Herbert M. Mandel

INTRODUCTION Designers of major public works projects in the past have displayed varying degrees of environmental consciousness, and tunnel designers in particular have always had to deal with certain environmental considerations - ventilation, lighting, aesthetics - as matters of primary design. Today, however, with a widening sector of the public becoming environmentally aware, tunnels are treated as elements of whole transportation systems, and are subject to increasing environmental scrutiny. The Route H-3 tunnels in Hawaii are examples of the time, care, and detail involved in a major rock tunnel project. Project Description The Route. Interstate Route H-3 is a proposed 10-mile highway crossing the Koolau Mountain Range on the island of Oahu, Hawaii, providing a direct connection between the Pearl Harbor area and the windward part of the island in the vicinity of Kaneohe. It is designed as a dual highway with provision to accommodate mass transit. As shown on Figure 1, the project includes two sets of twin bore tunnels (through the Main Koolau Range and through Red Hill), three highway sections of which two are through largely undeveloped mountain valleys (South Halawa and Moanalua), a viaduct, and three interchanges. From the Halawa Interchange to the Kaneohe Interchange, the proposed highway consists of two 3-lane roadways separated by a median where the highway is at grade. One lane of each roadway will not be constructed initially but will be landscaped and reserved for mass

Jan 1, 1974

By Salam Moubarak, Thomas Camus

"INTRODUCTION Since the introduction, several decades ago, of the first concepts of tunnel boring machines (TBMs), the unremitting increase of mechanized and automated tasks and the reduction of manual tasks carried out by human operators have gone hand in hand with the continuous improvement of these machines. In the present state of TBMs, the replacement of worn cutting tools is a critical, tedious, and dangerous manual operation especially for earth pressure balanced (EPB) and slurry TBMs. For such pressurized TBMs, hyperbaric interventions are used. They consist in replacing the pressurized soil/mud inside the chamber with compressed air that balances the face pressure. The operators can then ""dive"" into the chamber; however, because the human body cannot naturally undergo pressure changes, they have to follow strict procedures that have been developed for subsea divers, based on decompression stops. Indeed such interventions are actually quite often performed by professional deep-sea divers. The pressurized TBMS are consequently equipped with a manlock that allows for the required compression and decompression cycles. Hyperbaric interventions increase risk to the operators and require long decompression procedures that increase the TBM idle time and reduce its efficiency. At higher pressures, over 3.5 bar (ITA Report No 10, 2011), specific equipment and special gas mixes and/or saturation techniques are recommended (Lamont, 2012). Such procedures are even more expensive and time consuming although the duration of work in the pressurized area can be very limited for health and safety reasons. Contractors are therefore increasingly interested in automating these operations to reduce the risks to human workers and improve the TBMs performance. Moreover, the demand for new, ambitious and challenging tunneling projects (very deep, high pressure boring) is ever increasing, but the supply of suitable TBMs is limited and the risk from working in the hyperbaric environments becomes increasingly unacceptable. Impact of hyperbaric interventions The UK Health & Safety Executive has analyzed the consequences of working in intermediate pressure compressed air. The retrospective study of decompression illness (DCI) indicated that at certain pressures its incidence was around 2% of all exposures. More worryingly it showed that over 20% of the exposures commonly undertaken by shift workers in tunneling (those over 1 bar pressure for 4 hours or more) resulted in DCI. It was concluded that on some contracts up to 50% of shift production workers experienced DCI at some time during the contract, a situation which was considered to be wholly unacceptable (Lamont, 2006)."

Jan 1, 2016

By C. C. Bailie

This paper will be concerned with those mineable coal measures at depths necessitating deep mine operations in the range of 200 feet to 800 feet in depth. The area is generally classified as the Southern Illinois Field but more specifically includes that part of the state south of a line extending from St. Louis, Missouri on the west to Vincennes, Indiana, on the east. This embraces an area which presently includes a total of 38 shipping mines and 5 local or truck mines. Of these shipping mines, 22 are deep (shaft or slope) mines and the remaining 16 are strips. The average annual production of the shipping mines is around 29 million tons. The presently classified mineable reserves of the area are estimated at around 70 billion tons.

Jan 1, 1964

By C. A. Young

Previous experimental results have shown that an increase in temperature and/or oxygen concentration leads to an increase in the hydrophobicity of fluorite (CaF2) with adsorbed oleate. Subsequently, ex-situ Fourier transform infrared (FT-IR) transmission studies suggested that this increase in hydrophobicity was the result of double-bond reactions between adjacent oleate species adsorbed at the fluorite surface. Now an in-situ FT-IR study on single crystals of fluorite has been used to monitor this phenomenon using internal reflection spectroscopy (IRS) with the crystals serving as reactive internal reflection elements. The double-bond reaction has been correlated with in-situ adsorption density measurements. These results demonstrate that only the first chemisorbed oleate layer undergoes the double-bond reaction at an appreciable rate. However, multilayers of precipitated calcium oleate in the case of fluorite appear to react minimally even for oxygen saturated solutions at elevated temperatures.

Jan 1, 1991

By S. C. Sun

Very little information is available concerning the magnetic properties of minerals and only recently has there been any attempt to correlate magnetic susceptibility with varying chemical composition1. The work described here covers a study of the relationship and chemical composition of both the rutile and sphene types of titanium minerals. The relationship between the magnetic susceptibility of three selected mineral specimens and the applied field strength is also presented. Experimental: The equipment and procedures used in this in- vestigation for crushing and cleaning the mineral specimens and for determining the magnetic susceptibilities were the same as that employed by Spokes and Mitchell1. The particle size of-the measured specimens was limited to 270/325 mesh.

Jan 1, 1959