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By R. P. Fischer

Traditionally, molybdenum and vanadium have been used chiefly as alloy metals in steel. They impart similar characteristics to most steels, and to some extent one can be substituted for the other. In the United States during the 1950's the production of steel increased about 5 percent, and the reported consumption of both of these alloy metals in steel increased some 40 percent. In Europe during the 1950's the production of steel in¬creased nearly 100 percent. Data on the actual consumption of these alloy metals in European steels are not available, but production and trade records show that the European supplies of molybdenum increased about 150 percent and those of vanadium about 350 percent during the 1950's. If most of the molybdenum supplies in Europe are being added to steel, as seems likely, then the European steel industry has nearly caught up with the United State in the rate of consumption of molybdenum in steel. The vanadium supplies, on the other hand, are puzzling--unless Europe is adding mach more vanadium to steel than is done in the United States, it seems reasonable to assume that other uses are consuming moderately large quantities of this metal or that appreciable amounts of it are being transshipped from Europe. To the extent that a changing volume of supply signifies a changing pattern of use, the increased demand for molybdenum and vanadium in Europe should be of interest to domestic producers and consumers of these metals.

Jan 1, 1964

By C. C. Graham

In this paper, the problems which occurred on introduction of dense medium cyclone coal washing in Australia are reviewed together with the subsequent measures taken to obtain a satisfactory magnetite. Specification and testing of magnetite for exploration, quality control and in-plant check purposes is discussed. The disposition of Australian magnetite deposits in relation to the main coal producing areas is examined, and comments are made on the economics of mining, milling and beneficiating magnetite for coal preparation uses alone. Future trends in the Australian Coal Industry are predicted, and the need for a planned approach for the future is demons traced.

Jan 1, 1982

By Vi-Duong Dang

Lithium requirements in the next few decades for batteries and controlled thermonuclear fusion reactors (CTR) may exceed the availability of the current mineral and brine reserves. It is thus prudent to search for new reserves and resources to satisfy these and future lithium applications. The lithium content of the waters from the Smackover oil field. located in the Gulf Coast region of the United States, ranges from 100 to 500 mp/l and could represent a substantial new reserve. Experimental evidence described in the literature indicates that a specific chelating agent dipivaloylmethane (DPM), of the diketone type, has a specific selectivity toward lithium in the presence of other metal ions in aqueous solutions. Based in part on this unique property of dipivaloylmethane, a conceptual design of a full-size plant to extract lithium from the Smackover brine is presented in this paper. This study includes alternate flow-sheet development, design information on the major units of the process, energy requirements, and an economic analysis of a facility capable of producing 106 kg of lithium per year. The economics of three different process concepts depend primarily on the amount of water needing to be evaporated from the initial oil-field feed waters in concentrating the brine. The results, as a function of production rates, are indicated only in a general manner.

Jan 1, 1978

By J. R. B. Lima

The present work emphasizes the selection in the separation of the apatite/calcite by the direct anionic flotation versus the double flotation, with a reverse second stage of the Jacupiranga phosphate ore. The double flotation would allow the obtaining of two concentrated solutions: one of them mainly constituted by a calcium carbonate material (CaCO3) and the other one, phosphatic (apatite). The calcium carbonate concentrated solution is used for the production of cement. The presence of phosphatic material in the calcium solution is not desirable, phosphor being a harmful element to cement. On the other hand, smaller quantities of calcite in the phosphate concentrate would represent a substantial economy in the processes of production of phosphated fertilizers. These processes make use of sulfuric acid to the solubilization of the apatite and the presence of calcium material consumes acid. Also that, when carbonates are solubilized, unwanted products are formed resulting in losses in the process and diminishing the quality of the fertilizer produced. These characteristics are discussed in the paper and are compared to another Brazilian phosphate ore, the reverse route of which can be considered more adequate. The results are discussed according to recent discoveries, and special emphasis is given to the use of corn starch and its crucial role in promoting the selection in the direct flotation process.

Jan 1, 1993

By Thomas P. Oxford

The impact of recent legislation on Florida phosphate industry operations has been dramatic. The most significant influences are described: the National Environmental Policy Act of 1969; the Federal Water Pollution Control Act Amendments of 1972; and implementation of the Florida Environmental Land and Water Management Act of 1972. Further discussion includes: critical examination of the recently completed EPA Areawide EIS; potential effects of the Resource Conservation and Recovery Act of 1976; the Surface Mining Control and Reclamation Act of 1977; current local and state laws; and summary of studies on radiochemical effects of mining, seepage from gypsum ponds, and dewatering of waste clays.

Jan 1, 1979

By Dale K. Fields

With today's technological advances in mineral processing equipment, there is an increasing demand for accurate system control. This can only come about through representative sampling. The purpose of this paper is to guide you in the selection of sampling equipment and outline design parameters for the cutters used in dry and wet sampling without adding redundant mathematical probability formulas to your files. Special attention will also be given to the equipment used in conjunction with samplers and sampling systems, such as feeders, crushers, chutes, launders, and controls.

Jan 1, 1979

By John W. Graham

To start my talk, I thought it might be helpful for us to define the term "aggregate", so I went to the dictionary. Webster has several listings under "aggregate", and I found the following: "1. A mass or body of units or parts somewhat loosely associated with one another." Well, I didn't like that term "loosely" so I read on. "2. Crystals of one or more kinds of mineral or rock fragments." That sounded better, but I still read on. "3. Any of several hard inert materials used for mixing with a cementing material to form concrete or mortar." That sounded even better, but it should be a little broader. So I would like to define "aggregates" for you as follows: "Hard, inert fragments of rock or minerals used alone or with cementing agents to form products essential to nearly all types of construction." Usually aggregates are sand, gravel, or crushed stone, but other minerals such as clay or shale can be heated and become aggregates. What are some of the construction uses? Well, we've already mentioned concrete, as used in streets and highways, sidewalks and parking lots, airports and all kinds of building construction, not to mention bridges and swimming pools, and docks and breakwaters, just to list some of the uses. Our way of life couldn't exist without concrete. And you can't have concrete without aggregates,

Jan 1, 1977

By W. Choi

The present study revealed that the bioleachability of a chalcopyrite flotation concentrate is influenced by the semiconductor properties of CuFeS2. The overall reaction of biooxidation,

Jan 1, 1991

By Tore M. Larsen

The Rødsand Gruber mining company is a subsidiary of the Norwegian industrial corporation Elkem AS, and its mine is situated in the northwestern part of southern Norway. The ore from this mine is a relatively low grade, magnetite ore with a small amount of vanadium. The ore bodies are very irregular in shape, resulting in a high amount of waste rock intrusion in the stopes. The annual underground production in the mines is approximately 1 million t. Because of varying dimensions of the ore bodies, both transverse and longitudinal stopes are employed. The inclination of an ore body is usually 1.04 to 1.59 rad (60 to 90°), and the horizontal width varies up to 100 m. Sublevel stoping has been the traditional mining methods in this mine. Until a few years ago, the ore was primarily blasted using horizontal blasthole fans drilled from Alimak raises. Recently, however there has been an increasing demand for a les expensive mining method. Alternate systems were considered, and finally a method based upon large blasthole stoping was found to be the most suitable. GENERAL LAYOUT The general layout of a stope is shown in Fig. 1 As with all the figures in this chapter, only the prin¬ciples of the method are emphasized and the details may not be valid for any particular site in the mine. In transverse stopes, the horizontal width of the ore determines the length of the stopes. The average length is approximately 50 m, the width of the stopes is 20 m, and there is a 10-m wide vertical pillar between. The distance between the main levels is 60 m. Usually a horizontal (sill) pillar 10 m thick is left below the mucking level. Each stope is first undercut along the entire stope length. This undercut is made with 50.8-mm (2-in.) diam drill holes in a fan pattern. At the moment this is being done by a trackless Atlas Copco Promec jumbo equipped with two Cop 130 pneumatic rock drills. The drill drift is 4 X 4 m, and the crater is 20 m high. This leaves a 36-m stope height to mine with large blastholes. To achieve a fair portion of vertical drilling withlarge blastholes, there are two parallel drill drifts at the top of each stope. These drifts are 4 m high and 9 m wide, separated by a 4-m wide pillar in the middle of the stope. To ease the drilling of perimeter holes, the drifts extend 1 m into the vertical pillar on each side of the stope. The pillar will thus be only 8 m wide on the drill drift level, but 10 m wide down the rest of the stope.

Jan 1, 1982

By Gregg R. Bierei

Arch of Illinois is a mining complex comprised of two surface and two underground mines located in Perry County, in southern Illinois. The company a division of Apogee Coal Co. of St. Louis, MO. Arch of Illinois' two surface mines, the Captain and Horse Creek Mines, use large stripping shovels and cross-pit bucketwheel excavators to remove overburden from three seams of coal, the Herrin No. 6, Harrisburg No. 5 and Danville No. 7. All are considered high sulfur reserves. The two underground operations are managed by Arch of Illinois. They are the Kathleen Mine and the newly constructed Conant Mine, which began production in 1991. Both underground mines are continuous miner operations. They mine the No. 6 coal, which is about 1.8 m to 2.1 m (6 to 7 ft) thick. All coal is currently transported by truck to a central preparation plant located at the Captain Mine. This preparation plant produces 27 kt/d (30,000 stpd) of clean coal. Production in 1992 reached 5.9 Mt (6.5 million st) of saleable coal. Of that, about 66% or 4 Mt (4.4 million st) are produced by the surface mines and the rest the by under ground operations. Change is in the wind for Arch of Illinois. In 1988, 100% of all production (6.2 Mt or 6.9 million st) came from surface operations. By 1995, only 38% of production is scheduled from surface mines. And by the year 2000, 100% of production will from underground mining methods. Dwindling low ratio reserves, compounded by increasing environmental and land acquisition costs, coupled with more efficient underground mining equipment, have started an evolutionary trend toward development of underground reserves. For Arch of Illinois to maintain profitability of remaining surface reserves and to compete effectively mining underground, it must improve efficiency, productivity and cost reductions. These efforts are essential for maximizing current surface reserves and to ensure a continued existence in the presence of clean air legislation and the softening of the high sulfur coal market.

Jan 1, 1993

By C. J. Bise

Virtual Reality (VR) is a concept in which the human experience of perceiving and interacting with a computer-modeled environment is achieved through the use of sensors and effectors. It is an advanced fonn of computer graphics where the images are generated based upon where the user looks and how the user moves. As personal-computer-based (PC-based) instruction gains acceptance as an innovative approach to providing safety training, VR offers the capability of providing a multisensory, rather than merely a multimedia, mode of presentation. VR has been effectively used by the military for training tank commanders and by hospitals for training surgeons. However, these applications have been limited to small numbers of highly skilled participants. The purpose of this paper is to examine VR's potential for enhancing the hazard awareness of larger numbers of individuals in a broad-based approach to mine safety training, such as new-miner, annual-refresher, and independent-contractor training.

Jan 1, 1996

"INTRODUCTION Foam, unless intentionally created, in any industrial process presents operational problems, or at a minimum, is a nuisance. Some foam problems are unique to a given industry and others are common across many industries. A few problems foam presents to any particular industry are: (a) Poor Housekeeping, (b) Environmental impact, (c) Safety Hazards, (d) Slower Production Rates and, (e) Reduced quality of the end product. Defoamers address these issues. Sadly, the assumption in most industries is all defoamers are alike. In reality, a lot of chemistry is involved in the manufacture of even the simplest defoamer sold today and rarely are any two defoamers “just alike”. Today’s defoamers can include polymer chemistry, fatty esters, alkoxylated alcohols, silicone chemistry, silicone surfactants, ethoxylated and propoxylated block polymers, and a tremendous amount of emulsion chemistry just to name a few. This paper will discuss the various types of defoamers, defoaming mechanisms, the advantages and disadvantages of defoamer selections, and how to choose the proper defoamer for your application. Before a discussion of defoamer can be brought about, foam generation and composition must be discussed. WHAT IS FOAM? Foam is a colloidal suspension of a gas dispersed in a liquid. Most often foam consists of air dispersed in water. If a stream of air is introduced into a liquid, the bubbles produced assume a spherical shape. As the density of the bubble is less than the liquid the bubble rises. When the individual bubbles reach and pass through a surfactant free liquid they collapse. Air from the bubble dissipates and the liquid previously surrounding the bubble flows back.It should be noted a pure liquid will not foam. In the case of air dispersed in water a surfactant is necessary to make the water support a stable foam. A surfactant is a term used to describe a surface active agent; a compound with a hydrophilic end and a hydrophobic end on the same molecule."

Jan 1, 2016

By J. C. Johnson

The problem of estimating pillar capacity in coal mines has motivated development of a variety of empirical equations. Most of these equations have arisen from experience and a very limited set of measurements that have, necessarily, been focused on particular regions or coal fields. Their applicability is often limited to a specific range of pillar sizes. This is of particular concern in the design of large gateroad pillars and small barrier pillars between panels. The result has been a variety of equations and equation coefficients that can calculate load estimates to size pillars. Inclusion of these equations in more sophisticated loading models, such as boundary element methods (e.g. LaModel and MULSIM) has been hampered by absence of a function that describes specific variation of coal strength within the pillar. A singular exception, to our knowledge, is a function corresponding to the Bieniawski pillar strength equation. Because of this, it is the only coal strength criteria inherently available in most boundary element models. This paper presents a general method for deriving local coal strength, as a function of distance from the pillar rib, for an arbitrary pillar strength equation. Integration of this function provides the strength of pillar regions, or cells, needed for boundary element models. The method is demonstrated for the Bieniawski, Maleki and Holland-Gaddy equations. The Maleki and Holland-Gaddy equations contrast strongly with Bieniawski as strengths are extrapolated to large pillars and barriers. This development provides a tool for incorporating any of the proposed empirical equations into a boundary element model, thereby allowing the analyst to choose the most appropriate equation for a particular region, coal seam and/or pillar size.

Feb 23, 2014

By J. Kenneth Wittle

The DC Graphite Melter has been shown to be capable of processing radioactive waste materials. The process is characterized by its high temperature capability and operation in a closed system. From an environmental perspective, the control of emissions coupled with destruction for hazardous organic materials is mandatory. These same characteristics may be applicable to the minerals processing industry. Under normal operation, the system reaches temperatures for nominal operation of 1600°C, with an arc temperature in the order of 5000°C. The system temperature is determined by the melt temperature of the material being processed. In testing of a 750 lb/hour unit, temperatures of 2200°C were reached. Current focus is on finding waste treatment and metals recovery opportunities in the metals processing industry for his innovative technology.

Jan 1, 1999

By J. Frostiak

The Campbell gold operation of Placer Dome Inc. produces an arsenopyrite-sulphide concentrate which must be treated either by roasting, biooxidation or by pressure oxidation to obtain high gold recoveries. Pressure oxidation is a proven process and has the inherent advantage of meeting the stringent environmental regulations in the province of Ontario. A comparison of biooxidation and pressure oxidation was completed early in 1990 and the latter was selected by Placer Dome as the preferred process for replacement of the roasters. The commercial plant design was based on technology supplied by Sherritt Gordon and in July of 1991, the existing roaster operation was shut down and a new pressure oxidation plant was commissioned. The following summary describes the start up of the new facility and presents typical operating data.

Jan 1, 1992

By E. De Souza

Rockbursts and rockfalls cause very large safety and productivity losses in underground mines. One of the major unsolved problems of safe, economical rock support in underground mining has been that of maintaining anchorage during dynamic rock loading conditions or seismic related occurrences. It is recognized that the large displacements and high strain rates in excavation walls and underground structures cannot be countered by increasing the strength of stiff rock-reinforcing systems but must be accommodated by introducing yieldability into the support elements. This paper introduces a low cost yieldable support system which provides viable solutions to dynamic support loading. Such system should not only provide a feasible and more effective rock mass stabilization strategy but improve mine safety and reduce losses.

Jan 1, 1998

By William F. Riggs

In the fresh application of a frother, collector, or the change of any particular reagent, the interaction caused by this change is often overlooked since we attempt to solve a problem or improve a situation with use of a particular reagent without regard for the Interactions or side effects. When a particular reagent is added to a flotation circuit or substituted for another reagent, a series of chemical reactions occurs which. In turn, will create different physical responses. This discussion will provide a series of examples which have actually been experienced by the author.

Jan 1, 1994

Maximising margins in competitive markets demands superior productivity. Unfortunately, management systems developed early this century for other industries often drive counterproductive behaviours choking mining productivity. Many executives and managers waste valuable time and effort relying on simply training and communicating to improve managerial practices and attitudes. In covering practical human behaviour, the paper explains why this fails - and explains how to use systems to successfully drive improved managerial practices and attitudes. It highlights use of modern performance Measurement, Analysis and Reporting systems to drive behaviours and improve margins - without capital investment - and make executive and managerial work easier and more effective.

Jan 1, 1999

By G. J. Karabin

The Boundary Element Method of Numerical Modeling has become an increasingly popular rock mechanics -mine design tool. It has been used by the Roof Control Division, Pittsburgh Safety and Health Technology Center, MSHA, to aid in the resolution of complex ground control problems since 1985. This paper will present an overview of an evolving simulation process and details of methods utilized to generate necessary coal, rock and gob input properties. Also included is a description of a Deterioration Index System that is used to link model output to observed mine conditions and two case studies to illustrate that process.

Jan 1, 1995

By Robert V. Price

It is a pleasure to be here today to discuss coal's prospects with the Society of Mining Engineers of AIMS--- a group destined to play a crucial role in shaping our national energy future. Much has been said lately about attaining domestic energy self-sufficiency, but to date, little has been done. Oil tankers from Venezuela and Kuwait continue to glide across the seas to meet our incremental energy needs. Meanwhile, our principal domestic energy resources -- oil and natural gas reserves in the Outer Continental Shelf and the oil shale deposits and the coal lands of the West -remain untapped. Help, however, appears to be on the way. In a forceful address last fall, President Ford called for the elimination of oil as a fuel for base-loaded power plants and its replacement with coal by 1980. He also urged the accelerated leasing of federal lands on the Outer Continental Shelf, the resumption of coal leasing on federal lands, and the development of a new energy conservation policy. There are, of course, many details left to be worked out. Language must be developed to put statutory flesh on the conceptual bones spelled out by the President. Congress must act. Regulations must be approved and tested, if need be, in court.

Jan 1, 1975