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By R. L. Unger

Restricted fields of vision are a common problem with underground mining equipment. Also, when lighting systems are provided, they may be positioned where they cause glare. This restricts the visibility around the machines even further. To help address these problems, the U.S. Bureau of Mines has developed a PC based software package to aid in the analysis of certain human engineering aspects of mining equipment design. The software is available for use by equipment manufacturers and mining companies for design work on new machines, as well as for evaluating proposed modifications to existing machines.

Jan 1, 1994

[Aamot, Olav Crone, (M'29) Chem. Engr., Elektrokemisk, Raadhusgt. 23, Oslo, Norway. Abadilla, Quirico A., (M'38) Min. Engr., Dir. Bureau of Mines, Manila, P. 1. Abbott, Agatin, (J'40) Asst. Geol., Trench Mine, Patagonia, Ariz. Abbott, Clarence E., (M'04) Civil Engr., V.P., Tennessee Coal Iron & R.R. Co., 1642 Brown Marx Bldg., Birmingham, Ala. Abel, Raymond L., (M'28) Prof., Chem. Engrg., Univ. of Pittsburgh, Pittsburgh, Pa. Abel. Walter D., (M'32) Min. Engr., Div. of Corporations, State of Calif., 403 California State Bldg., Los Angeles, Calif. Abele, Louis T., (M'31) 4800 Patterson Ave.. Richmond, Va. Abell, Leo M., (M'31) Research Met., Mount Morgan Ltd., Mount Morgan, Queens., Australia. Abenius, Hakan V., (M'37) c/o Falu Gruva, Falun, Sweden.]

Jan 1, 1940

By John R. Holliday, William Marcum

Apogee Coal Company, DBA Arch of West Virginia, faced the challenge of drilling and blasting over one million cubic yards of high temperature overburden at its Ruffner surface operation near Logan, West Virginia. The overburden was removed above the Upper Five Block seam that was previously deep mined, abandoned, and later engulfed by fire. Borehole temperatures were measured above 700” F.

Jan 1, 1996

By Fred Drury

I spent 38 years in the Industry in a variety of sales, technical and management positions. I started out with Hercules, then was one of the founders of ECONEX, a large regional Distributor, and finally served with Dyno Nobel as a global Vice President, based in Oslo, Norway. When I retired in the fall of 1998, I looked forward to spending a lot less time traveling and a lot more time around home. After 4 years, I’m still traveling and still wondering how to find a few more hours in the day.

Jan 1, 2003

By G. J. Hundman

Control of respirable dust produced by auger type continuous mining machines is normally attempted by water sprays from fixed nozzles mounted on the frame of the machine. In tests conducted under this contract, a 'wet auger' system was used, where the spray nozzles were mounted on the rotating auger itself. The tests were conducted at the Hunter mine of Smith and Stover Coal Company using a Jeffrey 1.00L auger miner. Operating the mining machine in the wet auger mode, it was found to produce 47 pct less respirable dust than when the fixed conventional sprays were used. On section dust levels were reduced too 3.5 mg/m3 which is equivalent to approximately 2.0 mg/m3 for a full shift portal to portal sample. The major difficulty that had to be overcome was the development of a simple reliable water transfer mechanism to get the water into the rotating augers. This was successfully achieved by the development of a water-through-the-shaft water system. This system can be retrofitted to existing machines and is available in kit form.

Jan 1, 1977

By G. R. Hopkins, E. W. COCHRANE

The number of completed petroleum refineries in the United States continued to decline in 1937 , but the total capacity to process crude oil continued to increase . These facts were ascertained in the Bureau's annual canvass of refinery capacity as of January 1 , 1938 . Several important changes were made in the census questionnaire for January 1 , 1938 . First , the basis of reckoning cracking capacity was changed from cracking stock charged to cracked gasoline produced . Although this is a definite improvement , in that it is no longer necessary to consider the yield , it is unfortunate that the data for January 1 , 1938 cannot be compared with cracking - capacity statistics since 1925. Other changes or additions included separating capacity at operating plants into that actually operating and that closed down ; collecting data on capacity added or retired during the previous year ; breaking down idle capacity according to physical status ; and separating new capacity into that built for replacement and that built to augment existing capacity . Prior to January 1 , 1938 , the total capacity of an operating plant was listed as " operating " even though some stills might have been closed down ; furthermore , the only capacity reported as being under construction was that of new plants that were being built on January 1. To make the statistics clear , the totals for the United States as of January 1 , 1938 , are given on both the old and the new bases . On January 1 , 1938 , there were 551 completed plants compared with 572 the previous year . Ten new plants were under construction on that date compared with 11 the year before . The greatest number of completed plants recorded was 632 on January 1 , 1936 ; since then , competitive conditions , particularly in the East Texas field , have been instrumental in reducing the number of small independent plants . The total crude- oil capacity of the completed refineries on January 1 , 1938 , was 4,351,151 barrels , of which 3,970 , 196 barrels ( 91 percent ) represented the capacity in actual operation and 380,955 barrels ( 9 percent ) was shut down . The " shut -down " capacity ( 199,875 barrels on the old basis ) was the lowest since pre- depression days , chiefly because numerous idle East Texas plants were removed from the list . The new method of compiling the statistics sheds considerable light on excess crudeoil capacity , which has been the subject of considerable speculation in recent years . The highest daily average crude runs to stills reached in this country was about 3,460,000 barrels in September 1937. At that time , the total crude - oil capacity was about 3,925,000 barrels . This indicates that at peak operation the excess capacity was somewhat less than

Aug 1, 1938

By James R. Boyle

The value of mineral production increased 6.2% in 1976. With the exception of coal, practically all commodities registered an increase in production and value; most had an increase in unit value. Total value exceeded $1 billion for the first time. The increase in nearly all nonmetallic mineral production was a complete reversal of the 1975 experience. Alabama led the Nation in the production of crushed marble and was second in bauxite and scrap mica, third in oystershell, third in kaolin, and fifth in dimension limes-tone and dimension marble. International Trade.-The international trade passing through the Mobile customs district was valued at $2,524 minion in fiscal year 1976, up 20% from that of the previous year. Of the total value of trade passing through the district, 52% of the value of experts and 89% of the value of imports were handled through the port at Mobile. The major export Commodity was coal through McDuffie Coal Terminal which amounted to nearly 2.9 million tons, up from 2.4 million tons in 1975. Coal exports were to Japan, Italy, Turkey, the United Kingdom, and Brazil. Other exports were cement (114,000 tons) and [ ]

Jan 1, 1979

By P. Ret, E. Üstiindag, R. Dieckmann, R. Subramanian, S. L. Sass

"Partial reduction reactions in the Ni-AI-O system, starting with the spinel compound NiAI20 4, are used to form metal-ceramic microstructures. By suitable choice of processing parameters, such as reduction temperature, oxygen partial pressure and time, two different morphologies of nearly pure Ni particles, equiaxed and rod-like, form within a ceramic matrix, which is either a-A12O3 or a metastable ""defect spinel"". Electron microscopy studies were performed for microstructural characterization, phase identification and chemical analysis. The fracture toughness of the Ni-AI2O 3 mixture was significantly improved with respect to that of the original spinel phase. The important issues that must be addressed to form useful metal-ceramic microstructures by partial reduction reactions rue discussed. It is shown that cracking at the original spinel grain boundaries, likely due to the large volume changes associated with the reduction reaction, can be avoided by the addition of small amounts of ZrO2• Initial results illustrating effect of ZrO2 on the microsuuctures are presented.IntroductionEngineering materials used in load bearing circumstances, particularly under extreme conditions (e.g. high temperatures or stresses), generally are formulated with complex microsuuctures. Such composite-like materials can possess properties unobtainable by either of the individual constituents. With metal-ceramic composites, for example, a material can be obtained with an optimum combination of the low density and high strength of the ceramic, and the toughness of the metal. For high temperature service, where demanding conditions are often present, for example, inside jet turbine engines, a successful new material must have low density, high Young's modulus as well as good oxidation resistance, strength, fracture toughness, creep and fatigue resistance. The candidates include intermetallic compounds, and metal-ceramic, intermetallic-ceramic and ceramic-ceramic composites."

Jan 1, 1994

By A. P. Chaves, D. Jose Neto, M. G. Bergerman, E. S. Mano

"More complex ore comminution and concentration operations have found increasing application in the mining industry due to lower grades and higher complexity of the available ores. An alternative to coping with the higher capital and operating costs of ore processing plants is the use of pre-concentration stages. They allow removing a significant mass of material with little or no content of the relevant mineral before the ore is fed into the processing plant, with the consequent reduction in the mass to be processed in downstream operations. Significant benefits arise out of the use of pre-concentration, such as higher contained metal output without the need to increase the grinding or flotation capacity, and longer mine life. The grade of marginal ores could be enhanced to a level that would make their exploration economically feasible, which would result in increasing exploitable reserves. Nevertheless, few studies to date have assessed the resulting impacts on ore grinding energy consumption and wear after the gangue is removed through pre-concentration operations. This study evaluated the energy consumption and wear of grinding circuits in Brazilian mining operations in which the feed has gone through a pre-concentration stage. Such assessment was based on different samples of sulfide and oxide ores. Laboratory tests were carried out to investigate the power consumption and wear of grinding circuits with and without a pre-concentration stage. Laboratory test results were used to simulate industrial grinding circuits based on both alternatives and illustrate the environmental and economic benefits of each one.INTRODUCTION Increasingly complex ore concentration operations in several stages have found broadening application in recent years in view of lower grades and higher complexity of the available ores. An alternative to coping with the higher capital and operating costs of ore processing plants is the use of pre-concentration stages. Different ore processing technologies can be used for that purpose, such as magnetic separation, density segregation, and separation methods based on high-tech sensors (ore sorting). Currently, the most common methods are gravimetric processes, in view of their low cost, particularly jigging and dense medium separation methods, such as the drum and cone separators manufactured by Western Machinery Company, Teska, Drewboy, Norwalt, Dynawhirlpool and Tri-flo, and dense medium cyclones (CAMPOS; LUZ; BRAGA, 2010). The use of dry ore sorters has also grown significantly in recent years (Jose Neto et al. 2017). The selection of the separator type depends essentially on the ore particle size, required flows, and operating density ranges. All these methods may even be used after preferential blasting in mining (Grigg & Delemontex, 2015)."

Jan 1, 2018

By Donna L. Anderson

This information circular documents the status of a laser-based guidance system to track and control the tramming maneuvers of a continuous mining machine. The work is part of a multiple project effort at the U.S. Bureau of Mines to develop technology for computer-assisted mining systems. The system includes stationary offboard laser-scanning sensors that report the angular coordinates of retroreflective targets on the mining machine. A microcomputer system processes the angular coordinates, determines position and heading, handles requests for data, and controls tram maneuvers of a continuous mining machine. This report describes the hardware for the sensor and computer systems and the software algorithms for continuous miner position and heading determination, closed-loop tramming, and data request handling. Improvements made to the system since previous documentation include the rewriting of the software on a stand-alone real-time microcomputer system, the implementation of real-time programming techniques, the use of a new version of the laser sensor, and the design and development of explosion-proof enclosures for the lasers and corresponding power supply.

Jan 1, 1991

By D. D. Hogarth

"Edward Haycock, Engineer and Public Contractor Edward Haycock was born in Shrewsbury, England, June 14, 1813. His father was John Haycock, a timber merchant and soap manufacturer, residing at Swan Hill Court, Shrewsbury, and his mother Esther was the daughter of William Hilton of Hempstead, Hertfordshire. Edward's paternal grandfather, John Hiram Haycock, was the first of a line of architects that ""changed the face of Shrewsbury"" and ""provided some of the best examples of typical Victorian architecture in Shropshire""(1). Nothing is known of Edward's early life or education, although it appears that he made no attempt to follow this artistic trend. In 1833, Edward immigrated to Canada. The following year, he married Mary Butler, daughter of Johnson Butler, a Lieutenant-Colonel in the Lincoln Militia during the War of 1812. Mrs. Haycock, as co-heiress of Johnson Butler's estate, was assigned 600 choice acres of farmland in Brooke Township near present-day Sarnia. This alone would have guaranteed a tidy income, but the Haycocks soon disposed of this land, the last lots being sold in May 1840. Instead, Haycock turned his hand to engineering and, for a number of years, was employed by the Great Western Railway first in Woodstock and later in Hamilton. He then moved to Port Hope, tried farming, worked in the engineering office of the Port Hope, Lindsay and Beaverton Railway Company, and later constructed a portion of this railway(2). During his stay in Port Hope, Haycock met his future partners Ralph Jones, a contractor, and Thomas Curtis Clarke, chief engineer with the P.H.L. and B. Railway Company. The alliance was styled Jones, Haycock and Company and their most successful venture was the construction of the Government Buildings in Ottawa. This work was the crowning achievement of Haycock's career and, no doubt, his proudest moment was at 11:30 a.m., April 2, 1860, when his daughter Mary Emily, then a little girl of 4, with a special silver trowel ceremoniously laid the first stone. Of special interest in this project were the quarrying operations, which introduced Haycock to the art and difficulties of mining as well as to the potential returns of mines. Sandstone, for facing, was drawn from four quarries, 10 to 12 miles from the Departmental Buildings. Haycock seems to have been in charge of these operations, which in the early stages involved an average labour force of 86 men and 43 teams. However, by 1861, quarrying had declined in importance and the contractors were able to concentrate whole-heartedly on the construction site."

Jan 1, 1999

"Foreword by Emily SarverAssistant professor, Mining and Minerals Engineering, Virginia Tech, Blacksburg, VAThe Mineral Processing Division hosted its fifth Student Poster Contest during the 2014 SME Annual Meeting and Exhibit in Salt Lake City, UT – and, by all accounts, it was a huge success! This year, the contest more than doubled in numbers of individual entries and schools represented. A total of 30 students participated, including 23 graduates and 7 undergraduates, representing 13 US and international institutions: Colorado School of Mines, Michigan Tech, Missouri University of Science and Technology, Montana Tech, New Mexico Tech, South Dakota School of Mines, University of Kentucky, University of Utah, Virginia Tech, West Virginia University, Autonomous University of Chihuahua (Mexico), UNAL Medellin (Colombia), University of British Columbia (Canada). In addition to constructing their posters, students submitted abstracts and gave short oral presentations highlighting their research. Based on tallied scores from all three components of the contest, the judging panel selected 1st, 2nd and 3rd place winners at the undergraduate and graduate levels, which were announced during the MPD Luncheon on February 26.In the undergraduate division, University of Utah’s Lucas Pich was awarded the 1st place prize for his poster “Solid-liquid mixing studies in lab-scale flotation tank using electrical resistance tomography.” His extended abstract is included in this issue of Minerals & Metallurgical Processing. Joshua Chidester, also of Utah, won 2nd place for his poster presenting “Evaluation of detectors for radiotracer RTD measurement by MCNP.” And Lucas Rojas-Mendoza, of UNAL Medellin, took 3rd place for his poster on “Preg-robbing in Colombian gold ores.”In the graduate division, 1st place went to Caelen Anderson, of the Colorado School of Mines, who also placed in this contest in 2012 and 2013! The 2nd and 3rd place prizes were awarded to Jacob McDonald and Joseph Halt, respectively, both of Michigan Tech. Extended abstracts describing the work of these up-and-coming researchers are also included in this issue.The 2014 Contest was chaired by Emily Sarver (Virginia Tech) and Lisa Schlink (Freeport-McMoran Copper and Gold, Inc.). Aaron Noble (West Virginia University), David Perkins (Derrick Corporation) and Derek Novotny (Eriez) graciously served on the judging panel this year.Special thanks are extended to all sponsors of the 2014 MPD Student Poster Contest, and to all student participants. Please watch for upcoming details on the 2015 Contest. We look forward to seeing you in Denver!"

Jan 1, 2015

By M. F. Koehler

[THE LITERATURE contains relatively few thermodynamic values for interoxidic compounds, and these often are unreliable. This is especially true of data for ferrites and aluminates for which heat of formation determinations may involve extreme experimental difficulties. This report contains the results of new experimental work for obtaining the heats of formation of five ferrites (Ca2Fe2O5, CaFe2O4, MgFe2O4,, NaFeO2, and LiFeO2) and one aluminate (CaAl4O7), and a review and revision of previous similar work of this laboratory on five aluminates (Ca3A12O6,, 12/7 CaO-Al2O3, CaAl2O4, NaA1O2, and LiAlO2), The results for the 11 compounds are combined with entropy and high-temperature heat content data to derive tables of heats and free energies of formation (both from the oxides and from the elements) for the temperature range 298° 1,800° K, The relative stabilities of the compounds are discussed. The presented data all have application to ceramic reactions, and those for the calcium and sodium aluminates are applicable in considering soda-lime sintering processes for extracting alumina from silicate minerals such as day and labradorite.]

Jan 1, 1961

By Hall G

The Mount Isa silver-lead-,zinc deposit possesses a number of features which sets it apart from usual occurrences of ores containing those metals. The deposit has been described in vario:us papers, but development upon deeper levels during the past two years has, yielded much information not hitherto published. Purpose of the present paper is to furnish a unified and coherent perspective by tracing briefly the full rock deformational and mineralization processes responsible for the ore deposition. The paper represents the outcome of ten years' organized geological effort at Mount Isa. Information contained in it supersedes that previously published.A bibliography of published articles relating to Mount Isa ore deposition is appended. In preparing the present paper previously published data have been drawn upon freely wherever applicable. The authors are especially indebted to the papers by Grondijs and Schouten, and by O'Malley and McGhie, which present results of systematic microscope studies of thin and polished sections from comprehensive suites of Mount Isa ore.

Jan 1, 1942

By E. J. Wasp, N. T. Cowper, R. A. Davis, W. F. McDermott

On October 26, 1967, the world's first long distance iron ore slurry line was put into service by Savage River Mines. The commissioning of this $5 million installation climaxed three years of development, testing, and construction. The mine and concentrator are located approximately 30 miles from the town of Waratah in a rugged semi-mountainous terrain. The open pit mine will produce approximately 5 million long tons a year of crude ore, which is ground in autogenous mills, separated magnetically, thickened and prepared for the pipeline. The 53-mile pipeline transports the 2,250,000 tons of concentrate north to Port Latta. The Port Latta facilities include the receiving, storage and thickening equipment for the slurry as well as filtering, balling and pelletizing equipment to produce the 2,250,000 tons of high grade iron ore pellets. Five vertical shaft furnaces are used for pelletizing.

Jan 1, 1969

By T. R. Ellis

The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned. Since 1981, the Securities and Exchange Commission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis. Between 1989 and 1995, all 50 states and essentially all federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers.

Mar 1, 2002

By T. R. Ellis

"The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned.Since 1981, the Securities and ExchangeCommission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis.Between 1989 and 1995, all 50 states and essentially all federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers."

Jan 1, 2002

By B. R. Mohal, F. F. Aplan, S. Chander

"The wetting behavior of coal has been determined in the presence of nonyl and octyl series of nonionic surfactants containing polyethoxy groups of different sizes. The wetting behavior was determined by a modified Walker technique and contact angle measurements. The results show that the wetting rate of coal varies with coal rank, structure of the hydrocarbon chain and number of ethoxy groups in the hydrophilic group of the surfactant. A close relationship has been observed between the wetting rates and the short-time advancing contact angles.INTRODUCTIONNonionic surfactants are used in many applications to improve wettability of solids. They can be used as dispersing agents [ 1 ] or dust suppressants [ 2-5] and to control the flotation, flocculation, filtration and, flowability of particulates. This study was undertaken to study the effect of a series of nonionic surfactants on the wetting behavior of coal. Two series of surfactants, namely, ethoxylated nonyl and octyl phenols were used. The nonyl phenol series con tains a linear hydrocarbon chain containing nine carbon atoms (CH3 ( CH2 )8-C6H4- ( OC2H4 ) n, where n is the number of ethoxy groups) . The octyl phenol series contains a branched hydrocarbon chain containing eight' carbon atoms ( ( CH3 ) 3CCH2C ( CH3) 2-C6H4- ( OC2H4 ) n ).Initial wetting rates — modified Walker techniqueWalker et al. [ 6 ] developed a sink test to determine the wettability of coal particles. In this technique, coal particles are dropped individually onto the surface of surfactant solutions of different concentrations, and the most dilute concentration in which coal would sink ""instantaneously"" is determine& This technique is a variation of a procedure initially developed by Draves and Clarkson [ 7 ] to determine the effect of surfactants on wettability of cotton fibers."

Jan 1, 1989

By Pei‑liang Xu, Jun Wang, Xi Zhang, Deng‑pan Qiao, Tian‑yu Yang

The surface backfill, serving as the operational platform for continuing mining in upward slicing and filling stopes, is required to possess sufficient strength and thickness. Currently, there are limited model methods for determining the strength and thickness of the surface fill body. By analyzing the mechanical actions on the surface backfill, it is determined that its stability is mainly influenced by the combined effects of normal and tangential uniform loads under full-load conditions of trackless equipment. Assuming a circular contact surface between the tire of the trackless equipment and the surface backfill, and utilizing solutions from elastic mechanics theories such as the Boussinesq and Cerruti solution, the stress and displacement distribution of the surface fill body were obtained. Based on the maximum vertical stress condition, where the surface backfill body undergoes maximum deformation while still in an elastic state, and considering the stress–strain relationship, a model for the strength and thickness of the surface backfill has been established. According to the research findings, the design for the strength and structural parameters of the surface backfill has been developed to meet the full-load operation of the Atlas ST7 scooptram, with a compressive strength of 1.32 MPa and a thickness of 0.5 m. Numerical simulation analysis results indicate that the stress and displacement of the surface backfill align with theoretical analysis results. Practical results from industrial application in the western section of the Dahongshan Copper Mine demonstrate that the designed strength and thickness of the surface backfill meet the operational requirements for trackless equipment, resulting in significant engineering application effects and economic benefits. The research findings hold significant importance for advancing the theory of backfill mining and have high applicability and promotional value for similar mines.

Mar 24, 2024

By Yongjie Yang

Experimental study on the strength and deformation characteristics of coal under cyclic loading provides guidance for designing coal pillar which is subjected to repeated mining influence during mining. This paper studies the strength, deformation and fatigue process of No.3 coal from Xinhe Colliery under cyclic loading by the MTS815.03 servo-controlled rock mechanics test system. The results indicate that coal is more susceptible to fatigue damage than other hard rocks. Under uniaxial cyclic loading, the fatigue failure ?threshold value? of coal is smaller than 78% of its uniaxial strength, and there is also some fatigue damage when cyclic loading and unloading experiment is carried out below the fatigue failure ?threshold value?. Axial deformation can be divided into three stages: Initial deformation, steady-state deformation and accelerating deformation. Transverse deformation can be divided into two stages: Stable deformation and accelerating deformation. When the transverse deformation begins to increase rapidly and the deformation recovers only slightly upon unloading, it?s a precursor to failure of coal. Under cyclic loading, fatigue failure develops through a process of compaction, strain hardening, and strain softening.

Jan 1, 2006