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By H. Foster Bain

THERE has never been a great civilized nation which did not have a mining industry; civilization cannot flourish without metal mining. Without tools we can have none of the 'industries that are the foundation of civilization and without metal mining we cannot produce the material of which tools are made. Therefore, if we have no metal mining we have no metals, no tools, no civilization. An example to illustrate this may be drawn from a recent article in the Saturday Evening Post which described the run-down condition of modern Athens. Athens is nothing but a busted mining camp! In its palmy days the Greeks so applied the leasing system to the silver mines of Laurium that the royalties, paid the expenses of government and instead of a tax bill the inhabitants received a pay check. The Persians came over to capture these mines but the Greek navy was built to defend them. When the silver mines played out, Greek civilization declined.. Our mining must continue if our civilization is to continue.

Jan 1, 1921

By C. H. Larsen

A 9-month study of the uses of wire rope associated with U. S. underground coal mining is reported. Rope applications are broken down into hoisting and nonhoisting applications where "hoisting" refers to transport in vertical and inclined shafts. The former receives the greatest emphasis since it represents the most critical rope application from the stand-point of production and safety. The discussion of hoisting practice includes aspects related to the mine operators as well as those related to the equipment builders and wire rope manufacturers. U. S. state and Federal laws regulating hoisting and wire rope use are also presented and discussed. Canadian and other foreign hoisting practice and laws are included. The state of the art in electromagnetic nondestructive inspection of hoist ropes is presented. Capabilities and use of one Canadian electromagnetic device are discussed in great detail. Conclusions are drawn regarding the present state of wire rope and hoisting technology in U. S. coal mines. Recommendations are made for improving rope practice, in general, and hoisting, in particular, consistent with greater safety.

Jan 1, 1971

By J. W. Thompson

Be if enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That deposits of coal, phosphate, sodium, oil, oil shale, or gas, and lands containing such deposits owned by the United States, including those in national forests, but excluding lands acquired under the Act known as the Appalachian Forest Act, approved March 1, 1911 (Thirty-sixth Statutes, page 9G1), and those in national parks, and in lands Withdrawn or reserved for military or naval uses or purposes, except as heroinafter provided, shall be subject to disposition in the form and manner provided by this Act to citizens of the United States, or to any association of such persons, or to any corporation organized under the laws of the United States, or of ;iny State or Territory thereof, and in the case of coal, oil, oil shale, or gas, to municipalities: Provided, That the United States reserves the right to extract helium from all gas produced from lands permitted, leased, or other- wise granted under the provisions of this Act, under such rules and regulations as shall be prescribed by the Secretary of the Interior: Provided further, That in the extraction of helium from gas produced from such lands, it shall be so extracted as to cause no substantial delay in the delivery of gas produced from the well to the purchaser thereof: And provided further, That citizens of another country, the laws, customs, or regulations of which, deny similar or like privileges to citizens or corporations of this country, shall not by stock ownership, stock holding, or stock control, own any interest in any lease acquired under the provisions of this Act.

Jan 1, 1921

By Jim Sadowski, Steve Stewart, Bob McMurdy, Martin Nevens

"Mohawk Garnet has been operating a small pilot plant near Sudbury, Ontario for several years attempting to produce commercially viable garnet. The challenges of operating a pilot scale mining, processing, and product handling operation as a full time plant have led Mohawk Garnet to seek a better way. In co-operation with Mohawk Garnet, Outotec (USA) Inc. has taken on the technical and design challenges of increasing garnet product from twenty tonnes per day to two hundred tonnes per day.Outotec performed a comprehensive test and flowsheet development program applying Outotec’s density separators, spirals, flotation, and other technologies to design a successful process for the separation and recovery of the valuable garnet for Mohawk.This paper explores the test program, the process flowsheet development work, plant design and preliminary engineering of a new garnet processing. The various technical challenges, process technologies involved, and design concepts will be discussed.INTRODUCTIONMohawk garnet has been operating a small-scale garnet mine and process plant in Wahnapitae, Ontario near Sudbury.The current operation was intended to be a pilot plant and so only produces 20-25 tonnes of garnet concentrate per day. The garnet is bagged and sold for use as abrasive. The process is inefficient with low yields, poor material handling and very high cost per tonne. Mohawk garnet approached Outotec to help them improve their garnet process and transform themselves into a larger scale and more efficient operation."

Jan 1, 2010

By R Adamian, F. T. Da Silva, D. H. Gameiro

Schytill and Geldart diagrams were developed for the TiO2-C-Cl2 system at 1 073 and 1 273 K, so as to define the hypothetical relations between particle sizes and chlorine velocity for simultaneous fluidisation of mixtures of anatase concentrate and charcoal for carbochlorination. It was concluded that the operating limits on chlorine gas velocity will be controlled by the behaviour of the reducing agent, mainly because of its lower density. An increase in temperature from 1 073 to 1 273 K will have only a small influence on the fluid-dynamic behaviour of the mixture. For bubble fluidisation, the maximum sizes 0.413-0.478 mm for anatase and 0.529-0.611 mm for charcoal will be adequate. When the particle size distribution is large, fluidisation will be feasible only if conducted in two stages, otherwise the residence time of the small particles in the reactor will be very short. New diagrams will be needed for the gaseous chlorides in the second stage

Jun 21, 1905

By B. W. Roberts, V. A. Phillips

A copper alloy containing- 25.5 at, pct Zn and 19.0 at. pct Ni, which was previously found to show an anoma1old.s hardening effect on quenching- from 600 "C and aging- at 400oc, has now been examined by neutron diffraction. No evidence of long-range order was found. The aged sample showed diffuse scattering- consistent with clustering. The anomalous hardening effect is now attributed to lattice strains caused by clustering rather than (long-range) order hardening. SOLID-solution Cu-Ni-Zn alloys (the commercial 'nickel silvers") have been reported to show anomalies in: change of resistivity on cold working,1-6 temperature coefficient of resistance,2-12 resistivity at low temperatures,13,14 parameter (vs temperature),2"4 calorimetric data,2,4 specific heat,15,16 dilation,2-4 and elastic modulus.17 The structure responsible for the anomalies is produced by annealing typically near 400°C and is rather loosely referred to as the ('K-Zustands" (K state), a term coined by Thomas1' who apparently meant simply that the arrangement of atoms on the sites deviated from that expected statistically. Thomas proposed that the K state occurred in a variety of (solid-solution) alloys such as Cu-Ni-Zn, Ni-Cr, Ni-A1, Ni-Cu, Fe-A1, and Fe-Si and is recognized because its formation is strongly temperature-dependent and results in an increase in electrical resistance which can then be decreased by cold working. Later workers on ('nickel silver" have interpreted the K state variously as short-range order, long-range order. or a combination. The present work was prompted by the discovery by Phillips and Jones19 of a substantial hardening effect when an 18 pct "nickel silver" alloy which is fairly close to the Cu2NiZn composition, was reheated in the range 150" to 450 C after previously quenching from 600°C or, alternatively. was slow-cooled from 600°C or above. The phenomenon was attributed to (long-range) order hardening. Due to the similarity in the atomic scattering factors of copper. nickel, and zinc atoms, the ''nickel silvers" are unfavorable for X-ray diffraction studies aimed at detecting ordering. Nevertheless Bialas et a1.,20 using a powder sample containing 47.96 wt pct Cu, 24.03 wt pct Ni, and 27.98 wt pct Zn, slow-cooled from 400" to 200°C taking 500 hr, observed weak super lattice lines. Further unpublished work" using an anomalous dispersion X-ray technique indicates that zinc atoms are regularly ordered at the corner points of the lattice cell, while the nickel and copper atoms are statistically distributed on the remaining sites. Köster 17 also observed X-ray superlattice lines, for example, in an alloy containing 43.5 wt pct Cu, 28.6 wt pct Ni, and 27.9 wt pct Zn superimposed on the basic fcc cell with a = 3.62 kX. He proposed a Cu3Au-type superlattice with the Ll2 structure in which the A sites were statistically occupied by copper and nickel atoms and the B sites by zinc. He adds that substitution must be possible so that zinc atoms partly occupy A sites. Below about 35 pct Cu, Koster had some evidence for a CuAu-type superlattice with the Llo tetragonal fcc structure with a = 3.82 kX, c/a = 0.88 which could be preserved by quenching. This is suggested17722 to correspond to CuNiZn. While the present work was in progress Hirabaya-shi et a1.23 made an independent comprehensive neutron-diffraction study of a single crystal containing 50.05 at. pct Cu, 26.57 at. pct Ni, 0.25 at. pct Mn, 0.13 at. pct Fe, balance zinc. The presence of manganese and iron is surprising since the crystal was supposedly grown from high-purity metals. The homogenized crystal showed evidence of long-range ordering after an anneal of 5 months at about 300°C. Three possible crystal models were proposed. A curious feature of their results23 is that they could not find any neutron-diffraction evidence of ordering in a powdered polycrystalline near-stoichiometric Cu2NiZn alloy. There appears to be some essential difference between a near-stoichiometric Cu2NiZn alloy and one somewhat further off stoichiometry as used by the present authors. Thus Sato14 was able to reproduce the low-temperature resistivity anomaly reported by one of the authors13 on the present alloy if he used a similar composition, but found the normal behavior of the residual resistivity in a near-stoichiometric alloy. satol2 found that the resistivity of a cold-drawn slightly off-stoichiometric alloy increased to a maximum on isothermally annealing at 300°C and then decreased ("over-aged"). Since he could not explain this on the basis of ordering phenomenon, he proposed that zinc atoms were segregating to stacking faults (Suzuki effect) and found etching bands on the surface by replication which were attributed to the widening of faults. Sato suggested14 that the hardening effect observed by Phillips and Jones19 is partly due to the Suzuki effect. EXPERIMENTAL The starting material was 1/4-in.-diam hard-drawn rod of a commercial 18 pct "nickel silver" alloy identical with that used in a previous study by Phillips

Jan 1, 1967

By J. E. Hipp

Three electrostatic field sensing proximity warning devices were tested using full-scale cranes and power line systems, a scaled model facility, environmental testing facilities, and theoretical/numerical analysis. The design objective of each device is to assist in safe crane operation near overhead power lines. Several design deficiencies (varying from device to device) were observed, including inadequate overlap in sensitivity ranges, utilization of vacuum tubes and electro-mechanical parts, temperature sensitivity and inaudible alarms. In addition, the testing showed major device limitations including sensitivity to boom orientations and length, polarization dependent responses, and unreliable operation in the presence of multiple power line circuits. The multiple power line circuit problem is intrinsic to electrostatic sensing devices. The remaining deficiencies and limitations are correctable within a state-of-the-art design. This investigation is not intended to evaluate the safety aspects or policy of utilizing proximity warning devices. Rather, the purpose is to determine the performance characteristics of such devices in relation to the criteria specified in proposed MSHA regulation 77.805-4 (i. e., the devices must alarm at a distance of 10 feet from the power line).

Jan 1, 1980

The complex organic chemicals in coal differ from those in petroleum mainly by the ratio of carbon atoms to hydrogen atoms; this ratio is about 2 for coal and 1 for petroleum. By changing the ratio, coal can be converted into compounds similar to those found in petroleum. In. very simplified form, omitting here the special conditions required, the paths by which this can be done are: [ ] Part or all of the coal is first gasified by reaction with steam and oxygen, either in a gasifier or while the coal is still in place underground. The resulting gas is mainly hydrogen and carbon monoxide, with impurities that .must be removed before further processing by one of the following routes.

Jan 1, 1959

By Fernando Romero Lage

"Crushing and screening theory and application has remained fairly consistent in the last 50 years. The application of such equipment is guided by varied formulaic conventions and rules that due to the entropic nature of the process, remains more an art than a science. The variability of conditions creates an environment in which trial and error becomes the principal means of process balance and control. This paper illustrates some of the theories behind the process, plus other assumptions, postulates, myths and misconceptions that exist within the crushing and screening industry.INTRODUCTIONContinuous material balance calculations are habitually performed in the design of new comminution circuits as well as in the valuation of existing circuits. A continuous material balance calculation is one in which the input rate of material is equal to the output rate for each unit functioning in the circuit. At continuous analysis, there is no accumulation or losses of material within the system, as it is when performing a discrete event analysis.In order to produce viable and manageable mine-to-mill material, whether it is ready to leach or ready to mill, we must reduce the material in a series of stages. The power demand increases as the material size decreases, as it is when folding a piece of paper successively. As with the paper, there is a crushing size limitation that is a consequence of the mineral properties such as work index, moisture, viscoelasticity, etc. Comprehensive knowledge of crushing plants in both the aggregate and the mining industries show that, after three stages of crushing, a particle size distribution originating from a blasted deposit can be reduced from an nominal maximum size of 500 mm to a nominal maximum size of 12 mm. if the last stage of crushing is set in closed circuit, the screen openings will be able to yield a smaller top size.Achieving steady and continuous material balance poses major difficulties as crusher lose their settings, screens blind or peg, and material characteristics change geographically or seasonally. Overloading conditions in crushers and screens are nothing but counterproductive, and the net losses of an unbalanced circuit can be overlooked when mining operators are paying a lot more attention to the evermore complex systems downstream.It is not simply the crushing of the mineral but achieving the right size for the downstream milling process that will yield the maximum amount of energy savings."

Jan 1, 2010

By J. E. Nesset, S. R. Rao, J. A. Finch

"For base metal sulphides, iron rejection starts in mineral processing. This review focuses on changes in plant practice specifically to improve iron sulphide rejection by control of contaminant ion effects and discusses selected general innovations in mineral processing that can be expected to play a role. One group of changes to control contaminant ions is in size reduction (the use of stage grinding and inert stirred milling) and another is in system chemistry (order of reagent addition and exploitation of the flexibility of sulphoxy reagents). Plant examples illustrate the successes, indicating that there are several options available. The general innovations start by considering the new tools for measuring gas dispersion properties and quantifying froth characteristics by imaging. Examples of their application to improve concentrate quality illustrate the potential. Other innovations stress adapting geostatistics to model variation in milling and flotation response to provide feed forward control and rigorous application of statistical experimental methodology in plant test work. An example from one concentrator shows improvements in concentrate quality from application of basic principles can be impressive.INTRODUCTIONThe more iron control (rejection) that can be accomplished in mineral processing the lower the subsequent metal extraction costs and environmental implications of iron disposal, particularly in hydrometallurgical processes. Iron rejection has been a contributing target to periodic attempts to apply mineral processing to nickel laterites and bauxites but the prime application is control of pyrite and pyrrhotite (iron sulphides) in the treatment of sulphide ores by flotation. In this paper some new concepts and innovations introduced in sulphide flotation plants over the past ten years or so (i.e., since a previous review [1]) will be outlined with examples of how they have contributed to improved “iron control”.To increase rejection of iron minerals, first the recovery mechanism should be understood. There are four principal ones, two physical in origin: 1, via locked particles (i.e., flotation of composite particles due to insufficient size reduction to liberate the minerals) and 2, through entrainment in the water reporting to the float product (an unselective process); and two originating from a response to the system chemistry: 1, true flotation (i.e., iron sulphides becoming hydrophobic) and 2, as a result of iron sulphides forming aggregates with hydrophobic particles (e.g., ”slime” coatings). There has been considerable effort to diagnose which of these dominates iron sulphide recovery; in many cases it is due to “chemistry”, in particular true flotation. The flotation effect often appears related to contamination by metal ions [1]. This can reduce selectivity in two ways: 1, metal ion species may activate iron sulphides, or 2, cause general depression which demands more vigorous flotation conditions (e.g., additional collector) with consequent loss of selectivity. This is where the review will start, by considering ways to control contaminant ions."

Jan 1, 2007

By Gene R. Reid

The contract objective is the development of an Automatic Fire Control System for Mobile Underground Metal Mining Equipment. The Phase I Report, which described the projected data handling plan, was published on July 24, 1975. The Phase II effort covered the period from July 24 through December 2 and accomplished the following objectives: ? Acquisition of data in accordance with the project data handling plan. Data were acquired through visits to twenty mine sites in ten states and Canada; visits to Bureau of Mines and MESA facilities; visits to mobile equipment manufacturers; and an extensive literature search. ? Analysis of accumulated data which provided the following specific types of design inputs: selection of the type of mobile underground equipment found to represent the greatest overall fire hazard; typical operating conditions for the vehicle; characteristics of the reported fire experiences; and performance, cost and maintenance factors affecting potential purchases of automatic fire control systems for underground mining equipment. ? Development of the AFCS design concept. Utilizing the data analysis results and considering the state-of-the-art of fire control system components, a recommended design concept was developed with particular emphasis placed on the need for a low cost and reliable system. Design trade-off studies are provided for the recommended system and for four alternate system concepts.

Jan 1, 1975

By J. J. Jakosky

THE method of electrical mapping of oil structures to be described possesses certain limitations, as well as certain definite advantages. It, in common with other geophysical methods, is not a panacea for the solution of all subsurface geological problems. It operates on differences in electrical conductivity of the geological strata, whereas the other most-used methods operate on (1) differences in magnetic properties, (2) differences in gravimetric properties, or (3) differences in seismic properties. This modification of the resistivity method is therefore able to obtain subsurface information under conditions not favorable to the other methods mentioned. Where the other methods have been employed with ambiguous results it may act as a complementary method.

Jan 1, 1936

By J. R. Alldredge

This Bureau of Mines report presents a computer code that has been developed for describing and testing the statistical distribution of general continuous data sets. The statistical distributions used include the normal, lognormal, exponential, chi square, gamma, and uniform. Histograms for observed and expected values are plotted for each distribution. An example using geologic data obtained from a study of the geometric properties of natural fractures in oil shale rock illustrates the use of the computer program, GDIST.

Jan 1, 1977

By E. D. Doney

The Kerr-McGee Coal Corporation's Galatia Mine's first longwall mining system was implemented on May 3; 1989. Start-up of the longwall face represnted the successful conclusion of an effort begun nearly four years earlier. This paper-presents a case history of the processes that led to the longwall's implementation, and the subsequent mining of the first 7,900 foot long panel.

Jan 1, 1990

By William R. Yernberg

The Mineral Processing Plant Design, Practice and Control Conference was held from Oct. 20through 24, 2002, at the Fairmont Hotel, Vancouver, British Columbia, Canada. The conference was attended by nearly 400 of the world’s top mineral-processing specialists, including plant-design engineers, mineral-processing consultants, academics, suppliers and equipment manufacturers. The meeting was sponsored by SME and cosponsored by the Canadian Mineral Processing Division of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM). The conference covered all aspects of mineral-processing design, construction and operation. The meeting included more than 130 technical presentations. Topics included sampling programs, feasibility studies, design criteria, process technologies, construction, start-up operations and shutdowns. To stimulate interaction and discussion throughout the five-day conference, the sessions were presented consecutively. Attendees had the opportunity to attend every session.

Jan 1, 2003

By David H. Browne

(Pittsburg Meeting, March, 1910.) NICKEL has always been a fruitful mother of problems. Previous to the year 1906 nickel was regarded as an element replacing iron in copper-mattes, and it was believed that the same laws which governed the elimination of iron could be applied-to nickel. This conception has lately undergone a complete change, and nickel in all its stages is now regarded as an element replacing copper; in other words, copper-nickel is considered now as two elements, but as one metal. When we commenced our investigations on Monel metal we made a great many experiments on the conversion of mattes, both high copper and high nickel. We studied closely the composition of the mattes and the changes produced by the blow. We found in all cases certain agreements which we believe are due to some law. Briefly stated, our conclusions are as follows 1. Nickel is not an element replacing iron in matte. 2. Nickel-copper alloys act in the matte-blow like one metal. 3. Nickel-copper alloys follow, during the matte-blow, exactly the same laws as govern. the behavior of copper alone. This brings up the question : What are the laws governing the production of metallic copper, and what are the relations copper to sulphur and iron during the Bessemer blow ?

Apr 1, 1910

By Stavros A. Argyropoulos

Exothermic mass transfer takes place in various areas involving metallic systems, ranging from liquid metal processing operations to the growth of thin films in microelectronics. The formation of intermetallic compounds plays an important role in the exothermic mass transfer of metallic systems. Two types of exothermicity are identified , namely , Microexothermicity and Macroexothermicity. The former is encountered when small amounts of metals are mixed, while the latter is exhibited when a solid metal in a lump form is added into liquid metal. In this paper two types of exothermic mass transfer in metallic systems will be presented and reviewed. Mathematical modelling work for these types of exothermic mass transfer will be analyzed.

Jan 1, 1993

By John G. Parker

The rare-earth elements, sometimes known as the lanthanides, comprise the series of 15 chemically similar elements with atomic numbers 57 through 71. Yttrium, with atomic number 39, is often included in the group, because its properties are similar and it more often than not occurs in association with the lanthanides. Thorium is included in this survey due to its close association with the lanthanides, particularly in the mineral monazite. The lanthanides were first recognized as elements around 1750 and were the subject of much study by chemists during the 19th century. The purely chemical methods then available failed to resolve the strange intimate relationships between these elements, and it was not until about 1920 that the full series was explained.

Jan 1, 1971

By Jeffrey A. Yonkey, Timothy J. Lutz, Jacob L. Carr, Christopher C. Jobes

"Since 1984, there have been 39 fatalities involving striking and pinning of the operator and other workers by the continuous mining machine (CMM). In January 2015, the U.S. Mine Safety and Health Administration (MSHA) finalized a regulation to require proximity detection systems on all continuous mining machines except full-face machines (MSHA, 2015). Proximity detection systems are designed to stop machine motion to protect miners from striking/pinning hazards. Several MSHAapproved proximity detection systems are commercially available.NIOSH researchers have been involved in the development and testing of proximity detection technology since creating the HASARD system (Schiffbauer, 2002) and have recently conducted research intended to develop more advanced proximity detection technology for CMMs (DuCarme et al. 2013; Jobes et al. 2012; Carr, DuCarme et al. 2013 and Carr, Li et al. 2013). In addition, NIOSH has also conducted research investigating how the signals of a proximity detection system propagate (Li, Carr et al. 2013 and Li, Jobes et al. 2012) and have developed a novel method for determining the location of a personal wearable device (PWD) relative to the magnetic field generators (Carr et al. 2010 and Jobes, et al. 2012).To evaluate the performance of proximity detection systems implemented in industry, NIOSH researchers conducted tests in 2013 on three systems installed on CMMs at three underground mines in Illinois and West Virginia. The results of these tests indicated that, while generally consistent performance was observed, there were opportunities for improving performance. These results were presented at the 2014 SME Annual Meeting (Carr, Lutz, et al. 2014). Since that time, second-generation systems have become available to the industry and are becoming more commonly used.Beginning in early 2014, NIOSH researchers conducted underground testing of these secondgeneration proximity detection systems installed on CMMs. Five tests were conducted on four installations of second-generation proximity detection systems, with one installation being tested twice. The tests were conducted at mines located in Illinois, Virginia and Kentucky with seam heights ranging from 137 cm (54 in.) to 213 cm (84 in.). These tests were conducted using the same test protocol used during first-generation testing, which is summarized in the following section."

Jan 1, 2014

By Parry. V. F.

"SUMMARY This report reviews the status of the packaged-for industry as of 1941. A field study was made of 35 representative plants to obtain technics and economic data on different types of processes used to make packaged fuel in the Central States. The report includes a classification of processes, photographs of typical operations, designs of different plants, an analysis of costs of manufacture, and a study of the physical and chemical properties of fuel cubes.It was observed that many of the smaller plants were having troubles in the manufacture of packaged fuel as the price of materials and costs of labor advanced toward the higher levels of 1942. In some instances, the total cost of manufacture was as high as $5.00 per ton, while in the better, medium-sized plants it was approximately $3.25 per ton. The direct manufacturing costs, excluding investment and depreciation, ranged from $3.17 to $2.37. These costs permit almost no profit at small plants when packaged fuel sells for the same price as competing lump coal under conditions existing in 1941-42.It was found that the predominant troubles in plants were due to inadequate drying and insufficient mixing of the starch binder. It was ob¬served that in the better plants, where proper mixing of binder was attained high-quality packages were made if 50 to 70 percent of the moisture was removed in the drying ovens. Experimental data obtained in the laboratory show the relationship between the temperature of dry air and the time required to remove different percentages of moisture in wrapped orunwrapped coal cubes.The average physical and chemical properties of fuel cubes made by five processes are listed, and tentative standards for minimum physical qualities and methods for measuring quantity are giver."

Jun 1, 1944