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By James E. Norman

[The flotation of mica is mentioned frequently in the literature, but most of the references have dealt with the recovery of mica by the old anionic collectors. The first use of the new cationic reagents indicated their superiority as collectors in the flotation and agglomerate tabling of micas, feldspars, guartz, clay, and other acidic minerals, but the separation of these minerals from each other necessitated of the study of the flotation of each mineral.]

Jan 1, 1941

By S. Gößling-Reisemann

Most copper ores contain valuable co-products such as molybdenum, gold, silver, nickel, etc. Sulphuric acid and steam are valuable by-products, which are generated dur¬ing copper production. The environmental impacts from mining and refining therefore need to be shared between these by-products and co-products, an issue in Life Cycle As¬sessment (LCA) referred to as allocation. There are different, recognised methodologies for doing so: burdens can be allocated based on the market values of these commodities, they can be allocated by mass, volume, molar amount, functionality, or other physical, technical or economic factors. All of these methodologies have their respective merits and restrictions, and the choice is usually case specific. Nevertheless, the choice between alternative methodologies can have dramatic effects on the LCA results. Recycling in LCA has to be handled in a similar way, as it essentially constitutes a special case of co¬production. The existing standards (ISO 14040 ff.) allow different methods for imple¬menting recycling and allocation into metal LCAs (open loop, closed loop, value cor-rected substitution, etc.), which are still a subject of discussion in the scientific community. However, the methodology used can significantly influence the ecological profile of copper and copper products. We will present an overview of the different methodologies available for including recycling and allocation and give an analysis of how the meth¬odological choice affects the final LCA results. This work will be followed up by quantitative case studies.

Jan 1, 2007

By R. Hedin, M. Dunn

The Pennsylvania Department of Environmental Protection (US EPA 319 program) provided funding to aid a public-private effort in the installation of an environmentally-friendly system to treat abandoned mine drainage at Jennings Environmental Education Center (Pennsylvania Department of Conservation and Natural Resources). Through this cooperative effort among state and federal agencies, mining, excavation, and environmental companies, college and home school students, Girl Scouts, and volunteers, a successful multi-component passive system, readily accessible for upgrades and public education/research activities, was built. 90 people were directly involved in construction of this award-winning system and about 1000 people annually benefit from the educational opportunities.

Jan 1, 2002

By Mary S. Esfandiary

U.S. scientists attempting to maintain continuous surveillance of scientific information are confronted with two acute problems: The steady, even spectacular; increase in the volume of such information and the fact that much of it is published in unfamiliar foreign languages, According to the National Science Foundation, almost one-third of the world's scientific literature is published in languages that are read by less than 5 percent of U.S. scientists. Most scientists in the United States must rely on abstract journals and translations to obtain information on developments in research and investigations conducted in the non-English-speaking countries. However, there are problems involved in procuring suitable abstracts and translations and in obtaining such information as cheaply and rapidly as possible.

Jan 1, 1961

By R. Strydom, J. H. Selby

Published information is available on the radiological impacts of disposing of zircon sand in a landfill. Zircon flour by virtue of its finer particle size presents a different set of issues during disposal. This paper describes two options for disposal of such fine grained materials – namely incorporation into concrete aggregates and agglomeration by addition of cement. The study considers the radiological exposure of the public from such disposal methods and concludes that these options are viable alternatives for the safe disposal of waste zircon flour. The disposal of zircon into concrete aggregates at a rate of 10 per cent produces a sufficiently low effect to allow such aggregates to be used in building foundations or other such mass concrete applications. The use of cement agglomeration methods will also provide a safe method of landfill disposal provided at least 20 cm of soil cover is included.

Jan 1, 2003

By H. L. Bibbs, H. D. Snedden

"INTRODUCTION The use of beryllium and its alloys has increased rapidly during the last decade. Further expansion of its use is limited; in part, by lack of adequately developed ore reserves. The principal commercial beryllium mineral is beryl, which is found chiefly in pegmatites and produced for market as a byproduct of the mica and feldspar industries. The coarse beryl is mined selectively, sobbed and sorted by hand, and then sold without further beneficiation. The known reserves of coarse beryl are small. No method has been available for concentrating small disseminated beryl crystals, so ores of this type have not been mined or have been left on waste dumps. Disseminated ore in low-grade unmined areas and waste dumps on developed properties is a potential source of beryl, provided a method is developed for its beneficiation.Published literature on the concentration of beryl is lacking in detail or deals chiefly with tests on artificial mixtures of pure minerals, and procedures as given were not applicable to the beryl ores tested at the Salt Lake Station. The testing procedures described in this report are independent developments. By employing these procedures, beryl was satisfactorily con¬centrated from several run-of-mine and dump ores, although these ores wore low in grade and part of the contained beryl was finely crystalline and disseminated.Beryl, quartz, and feldspar, when ground to flotation sizes, are so alike in color and general appearance that they cannot he distinguished by visual observation. The progress of the work depended on rapid determination of the grade of test products by means of the petrographic microscope. Small samples of concentrates and tailings were often cut after each addition of reagents, dried, and examined under the microscope."

May 1, 1947

By Jorge Agramonte Bermejo

Dado que el Perú es un pais rico en carbón antracítico y con limitados yacimientos de carbones semicoquizables, la tecnología que predominará para una producción mayoritaria será en relación con el consumo de la antracita en la industria de acero y de otras que le signifiquen ahorro de divisas y petróleo. En ese sentido, el objetivo del texto radica en hacer conocer la potencialidad de los yacimientos, cantidad, calidad de recursos y reservas de los mismos.

Nov 8, 1982

By Donald W. Mitchell

Studies were made in the Bureau of Mines Experimental coal mine to evaluate the effectiveness of a few extinguishing agents and techniques for controlling a fire on a simulated mining machine. The investigation showed that water containing an alkali-metal salt or a surface-active (wetting) agent was more effective than water alone. For close attack, fog applications was the most effective technique studied; high rates of agent application controlled the fire more quickly than low rates. The ability to control the fire increased as the distance of attack decreased. Dry powders controlled the fire when applied by shovel but not when applied airborne by rock-dust distributor or by hand fire extinguishers. Dry alkali-metal salt powders (potassium and sodium bicarbonates and sodium tetraborate) quenched the fire more readily than limestone dust. In each instance the finer powder, the greater its effectiveness. In an open ventilated entry, smoke and hot gases backed against the air currents. An airspeed of 230 feet per minute was required to permit approach to within 10 feet of the fire. At lower airspeeds, approach could be made by extending the brattice across the bottom two-thirds of the entry, by pushing the smoke ahead with water sprays, or by discharging dust from a rock-dust distributor. In a dead-end entry, the fire was approached to within 30 feet by coursing fresh air along an airtight line brattice; however, it was safer, easier, and less time-consuming to attack the fire from a fresh-air base 100 feet away with a solid stream or by high-expansion foam; the latter method was more effective.

Jan 1, 1961

INTRODUCTION This paper was originally presented at the Platinum Adding Value Conference, held at Sun City from the 4th to 6th October 2004. Narrow reef mining may not be applicable to the base metal operations in Zambia, however, it is considered that the methodology used is equally appropriate to the development of technology and mining methods in mining environments other than narrow reef mining. The purpose of this paper is to explore the integration of technology and stoping systems. For the last hundred years the South African narrow reef mining industry has battled to control working costs in a labour intensive industry. It is only through the application of appropriate technology that change will occur. Stoping systems, because it is the stoping method and methodology that is at the heart of the mining system. Introduce a different technology that results in a more efficient stoping system and the mining system will look after itself. The technology applied to stoping in narrow reef mining, over the last 100 years, can be categorised as follows: ? The introduction of pneumatic rockdrills early this century. The cumbersome rig mounted units being replaced by smaller, lighter, hand held units that were then made easier to use with the addition of an air leg. (The so called Swedish method of mining.) As late as the early 1970s some drilling was still being carried out without the assistance of an air leg. ? Scraper winches to replace gravity and shovels to move rock both in the face and the gullies were first introduced in the late 1920s. ? Hydraulic props installed close to the face and capable of applying force against the hangingwall as well as yielding in a controlled manner under dynamic load arrived in the 1960s. In many instances these have now been replaced by yielding elongates fitted with water hydraulic tensioning devices. ? Some people argue that the introduction of tungsten carbide inserts, to improve drilling, was equally important.

Jan 1, 2005

[Mr. Scott Aberle Western Energy Co POB 99 Colstrip, MT 59323-0099 Mr. Brian L. Acton Oxbow Carbon & Minerals Inc 1601 Forum Pl-#P2 West Palm Beach, FL 33401 Mr. Laine W. Adair Genwal Resources Inc POB 1420 Huntington, UT 84518-1420 Mr. Thomas D. Aderman The North American Coal Corp 14758 Preston Rd #1100 Dallas, TX 75240-7891]

Jan 1, 1998

By S. R. Dismukes

Mining is likely to be targeted by The United States Environmental Protection Agency (“EPA”) as one of its key enforcement targets for fiscal year 2002-2003. Identifying the mining industry as an enforcement target, coupled with an increase in enforcement activity in recent years, places each mining operation at increased risk of receiving enforcement attention. A properly developed and implemented Environmental Management System (“EMS”) tailored for your operation is invaluable in reducing the risk of incurring liability for non-compliance. At the heart of an effective EMS is an audit program that checks the company’s compliance with environmental requirements. In addition, audit privilege (in select states), voluntary self-disclosure, and the attorney-client privilege serve as very effective tools for managing those liabilities that may arise during auditing a well-developed program. Of course, these latter tools are effective only if the auditing program is properly structured and properly managed. EPA and some states also provide varying degrees of immunity for environmental violations that are voluntarily disclosed in writing by the company. However, self-disclosure laws and policies typically prescribe stringent requirements for parties seeking to take advantage of them. For example: U.S. EPA has recently extended the time period in which to provide full written self-disclosure to 21 days. However, U.S. EPA’s revised Self-Disclosure guidance also addresses when a company obtains knowledge of a violation for purposes of triggering the 21-day clock and specifically extends the knowledge requirement to include the company’s agents and consultants. This expansion increases the difficulty companies may have in clearly defining and managing when they obtained knowledge. This difficulty increases the importance of managing factual development and the strategic use of other

Jan 1, 2001

By A. Baldwin

This report describes the engineering feasibility and economic advantages of a unique new mining machine using cutting bits that take a constant-depth linear cut in the coal face. The studies show that this innovative new cutting concept, being developed by the Bureau of Mines, can be designed into the basic continuous mining machine. The resulting miner would be attractive to mine owners because coal could be mined with minimum generation of airborne respirable dust, substantial increases in productivity, and elimination of methane ignition due to cutting.

Jan 1, 1977

By S. S. Cole, C. E. Wood, T. L. Joseph

"INTRODUCTION Iron ore containing titanium was first used in blast furnaces over a century ago. It is well known that TiO2 is a slag-forming material that will increase the amount of slag produced by the usual gangue materials, silica and alumina. Increase in the volume of slag due to the presence of TiO2 and a lack of information concerning its effect on the properties of the slag have prevented the general use of titaniferous ore. Also rather com¬mon belief among furnace operators that the bottom of the furnace builds up when ores containing TiO2 are smelted has militated against the use of titaniferous ore. This building up of the hearth has been attributed to the formation of copper-colored crystals of titanium cyanonitride, which have been observed in the salamanders of blast furnaces. Until recently the availability of nontitaniferous iron ore has left little incentive to use ore containing titanium.The presence of vanadium in certain deposits of titaniferous magnetite in New York State has created new interest in problems connected with the use of titanium-bearing ore. It appears that most of the vanadium in this ore can be recovered in pig iron, which can be blown in a converter to produce a slag containing vanadium in amounts suitable for the production of ferrovanadium.The Titanium Division of the National Lead Co. recently erected a largo mill to treat ore from Sanford Hill, in Essex County, New York, about 50 miles west of Port Henry. The ore deposit was acquired from the MacIntyre Iron Co. and is often referred to as Sanford ore. It is one of the largest deposits of Iron-bearing material to be found east of the Lake Superior region and is being mined by open-pit methods."

Jan 1, 1943

By Robert V. Spencer

"This report describes an examination and preliminary exploration of the Magnet Cove Rutile Co. property in Hot Spring County, Ark. The company in 1944 was producing titania for use in-the welding-rod and metallurgical industries but later ceased operations. The deposit appeared to contain potential reserves of rutile ore, and the Bureau of lanes in 1945 conducted an examination designed (1) to obtain samples for ore-dressing tests and (2) to gather information regarding the grade, character, and size of the deposit. This report presents the data obtained by geologic mapping, geophysical surveying, churn drilling, and core drilling. Beneficiation tests are being made at the Bureau of Mines Rolla, No. station, on the samples taken and will be discussed in a later report.The Magnet Cove operation had been called to the attention of the Bureau of Mines, and in view of the potential reserve of titanium-bearing material, it was decided to obtain samples for ore-dressing tests. Churn drilling was selected as a means of obtaining representative samples, and geologic mapping and geophysical surveying were done to throw more light on the nature of the deposit. Subsequently, a few holes were core-drilled.The property contains the NE1/4, W1/2 fractional NW1/4 and 82 acres of the N part of SE of sec. 18, and -29 acres of the SW1/4 NW1/4 sec. 17, all in T. 3 S., R. 17 W., Hot Spring County, Ark. The mine and mill are about 1 mile by graveled road northeast of U. S. Highway 270, a paved road connecting Malvern, 10 miles south and Hot Springs, 12 miles west. The area is served by two railroads, the Missouri Pacific, which passes through Malvern and Hot Springs and the Chicago, Rock Island & Pacific,,has a line connecting Malvern and Hot Springs an passes about 2 miles south of the property. A natural-gas pipe line and an electric power line reach the property."

Sep 1, 1946

By Vernon Helm, John S. Ball, Welton J. Wenger, William E. Haines

"INTRODUCTION Although the presence of sulfur causes many petroleum’s to be classified as ""low-grade"" because of the difficulties encountered in manufacturing products to meet rigid specifications, the petroleum industry is finding it necessary to use such crude oils to satisfy present needs. As the demand for petroleum products increases, and available reserves diminish, this utilization of high-sulfur crude oils will be accentuated. Programs designed to supplement the supplies of fuel available from petroleum by the manufacture of synthetic fuel from natural gas, shale oil, and coal are in progress. Such fuels, especially shale oil and, less so, oil from the hydrogenation of coal, also contain sulfur compounds which must be effectively removed. Thus, the need for fundamental research on the sulfur compounds that may be expected in petroleum and allied products is becoming greater as the industry is forced to call upon all available resources to meet the demand for petroleum products. In recognition of this need, the Bureau of Mines has inaugurated a long-range program assigned to furnish fundamental data concerning the presence, characteristics, and effects of sulfur compounds in petroleum and its products."

Dec 1, 1946

By George P. Demopoulos

In this paper the production and stability of crystalline scorodite (FeAsO4·2H2O) is discussed both on the basis of previously published work as well as recent work performed in our laboratory. The production of scorodite, especially from arsenic-rich and iron-deficient sulphate solutions offers a number of operational advantages such as high arsenic content, stoichiometriciron demand, and excellent dewatering characteristics. In addition to hydrothermal production of scorodite the work done over the last 10 years in our laboratory has determined that it is feasible to produce scorodite by step-wise lime neutralization at 90°C. The atmospheric scorodite possesses the same structural and solubility characteristics with the hydrothermally produced scorodite. Long term equilibration tests (up to 66 weeks) in the pH range 5 to 9 and temperatures from 22 °C to 75 °C revealed scorodite to undergo slow incongruent dissolutionyielding a highly metastable nano-sized 2-line ferrihydrite phase. The equilibrium arsenic concentration with this phase was 0.35, 0.96 and 5.87 mg/L at pH 5, 6, and 7 respectively at 22°C. In the presence of gypsum slightly lower concentrations were measured, this being more pronounced at pH>7. It was tentatively deduced that a Fe-Ca-AsO4 association (in the form of a phase resembling the mineral yukonite) contributes to the lowering of As concentration. Finally thermodynamic calculations determined that scorodite is stable in the presence of ferrihydriteunder oxic conditions up to pH 6.75 at 22 °C or higher pH at lower temperature and gypsum-saturated solutions. Keywords: Scorodite, Crystallization, Arsenic, Solubility, Stability, Precipitation, Disposal, Extraction, Processing, Metals, and Environment.

Jan 1, 2005

Crushing Plant Process Optimisation Design of processes in order to find the most efficient solution to a specific task is a difficult problem. Often the number of solutions are large and the optimal solution is therefore difficult to identify. Crushing plant process design is no exception from this statement. In order to find the best solution issues like equipment selection and process configuration must be mastered. The solution must both be technically feasible and preferably have a low operating cost. Since crushing plant design is a complex task with a large solution space it is basically impossible to master without a specialised tool. For a long time simulation softwares have been used to assist in the design process. These tools only give answers for how a user defined plant will operate. There are no tools with capabilities to consider different design options in order to determine what the most efficient solution looks like. In this paper a method for crushing plant design optimisation is presented. The novel method utilises a combined optimisation routine and expert system in order to find the most cost efficient solution to a given process task. The user will only need to define the feed material properties, the process capacity, and the end product requirements. The developed system will find the solution lowest production cost per ton.

Sep 13, 2010

By Steve Klein

Weak rock is an important consideration in tunnel design and construction due to the difficult ground conditions that are often encountered. Nevertheless, when conditions are favorable high advance rates can be achieved leading to economical tunnel construction. Successful construction of a tunnel in weak rocks depends on correctly anticipating the behavior of these unique materials. The objective of this paper is to provide guidelines that can be used to accurately classify the performance of weak rock in tunnels.

Jan 1, 2001

By S. S. Dean, B. Silkes

"INTRODUCTION The metallurgical-research program of the Bureau of Mines .for the past 15 years has emphasized the production of high-purity nonferreus metals through the utilization of our available resources, ores, reducing agents, fuel, and power.Ore dressing or concentration, has always been a vitally important part of nonferrous metallurgy, and the Bureau continues to give most of its attention to it. In the field of the traditional nonferrous metals, the Bureau staff has developed natural-gas reduction of zinc, the application of glomerule technique to preparing high-grade lead concentrates for Scotch-hearth smelting, the production of electrolytic antimony from precious metal-bearing ores, and the recovery of nickel from nickel-chrome-iron ores.In the field of light metals, the Bureau staff has developed several improvements in both magnesium and aluminum production and in alloys of these metals. In the so-called ""rare-metal"" field, Bureau activities have included the production of pure ductile titanium on a larger scale than heretofore attempted, the electrolytic production of cobalt, chromium, and manganese which may now take their proper places as bases for nonferrous alloys as well -as ingredients of special steels. The Bureau staff has investigated many of these new alloys. Investigations of methods of recovering vanadium from its low-grade domestic ores have given promising results. Methods for the preparation of metallic zirconium have been improved."

May 1, 1947

By E. V. Deshayes, W. E. Young

"INTRODUCTION The Camp Bird mine was investigated by Bureau of Mines engineers 3/ September 22 and 24, 1942, and April 29 and 30, 1944. In a subsequent report and supplement, it was recommended that core drilling be done below the 14th. level to determine if commercial ore existed at greater depths, and particularly if ore existed in the vein or adjacent thereto where it passes into the sedimentary formations estimated to underlie the volcanics approximately 400 feet below the 14th level.Seven diamond-drill holes aggregating 3,956 feet were drilled. Four of these holes were under the Hematite ore body and three were under the Big Discovery ore body. Two holes under, the Hematite ore body wore directed at angles but little steeper than the angle of dip of the vein and penetrated the sedimentaries beneath the volcanics close to the vein. Enough low-grade ore was found at the base of the Telluride conglomerate to indicate the presence of a large body of low-grade zinc sulfide ore. Two holes were directed to crosscut the vein at a depth of approximately 125 feet below the 14th level. No commercial ore was cut, but the vein showed the average width and same general characteristics as at the 14th level. One hole under the Big Discovery ore body was directed to crosscut the vein and test the base of the Telluride conglomerate in the footwall block. No commercial ore was found in either the vein or the sedimentary horizon. One hole was directed to test the base of the Telluride conglomerate in close proximity to the vein in the hanging-wall block. This hole was lost approximately 100 feet short of its objective, and a third hole was drilled to accomplish this same thing. The third hole was stopped approximately 50 feet short of its objective when failure of equipment caused a recess of the"

May 1, 1948