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By David A. Summers

Coal is increasingly viewed as one of the major fuel resources of this country for the remainder of this century. The need to extract a greater percentage of the coal in a given seam, together with advantages of improved safety, indicates that longwall mining will become more widely used within this time frame. A novel method of mining coal on a longwall face, utilizing high pressure water jets, is herein described. The mining machine proposed will exploit the stress conditions which exist on a longwall panel in order to achieve the required productivity while at the same time reducing respirable dust and methane ignition hazards. The water jets will excavate only the boundary of the extracted seam section, and thus the energy requirement of the machine will be minimized. The action of the machine is similar to that of an existing coal plow, except in that the wedge teeth of the plow are replaced by oscillating high pressure water jets. The machine can, therefore, cut to the depth and at the speed of existing shearer units at equivalent power levels. The removal of impact stresses from the machine will reduce downtime required for maintenance and replacement of picks and lower the load on the haulage motor of the system. The ability of the machine to increase the depth of cut without an increase in horsepower will further improve productivity when transportation systems to remove the greater production are in operation.

Jan 1, 1974

By Arman Hazrathosseini, Ali Moradi Afrapoli

Fleet management systems (FMSs) as the pivotal part of any surface mining operation find it essential to evolve from conventional into intelligent systems because of both Mining 4.0 requirements and some shortcomings inherent in conventional methods. However, this novel transformation needs to be investigated technically and strategically. To this end, the previously published research works on intelligent FMSs are explored to track the latest status of these third generation frameworks within the surface mining context. Following that, their underlying models are compared in terms of five categories of allocation and dispatching features to pinpoint the technical gaps ignored. Having drawn the future lines of research, the present article then leverages the popular SWOT analysis method to outline the strengths, weaknesses, opportunities, and threats associated with the advent of these intelligent FMSs in mines of future. By and large, the analysis indicates that advantages outweigh disadvantages. Solutions are offered to address the existing weaknesses and threats.

Nov 10, 2023

By D. J. Parker, D. Harrington, L. H. Harrison

"INTRODUCTION The necessity for protection against the hazards of lightning manifests itself from time to time in the mining industry by reason of loss of life, damage to electrical equipment, fires in surface structures at mines, and accidents in the handling and use of explosives. This paper is intended to assemble, correlate, and present some of the salient points embodied in the available literature on the subject and at the same time give some factual data concerning instances of such loss of life and damage to property, with special application to the mining industry.The annual loss of life and destruction of property by lightning is considerable; the former may be prevented to a limited extent, though use of common sense as to exposure is required and not always followed; the latter can be prevented to a considerable degree. The manufacturers of electrical equipment, through improved types of lightning arresters, have done much toward the protection of electrical equipment, with consequent safeguarding of life and of property. Education based on unfortunate experiences has gone far to discourage the handling of explosives and blasting accessories during thunder storms, especially in open pits and quarries, and to a much smaller extent in underground workings. The lowly lightning rod plays an important role in the protection of certain types of buildings (especially isolated buildings), stacks, monuments, and other structures.LIGHTNING PHENOMENAIn 1751, Franklin proved that, lightning was simply a visible display of electricity - an extended spark; and until a generation ago little had been added to his exposition to define the various phases of the phenomenon. Matters pertaining to lightning are discussed in the following references:"

Apr 1, 1948

By Paul M. Tyler, Amy B. CLINTON

The four elements fluorine (F), chlorine (C1), bromine (Br), and iodine (I) form the most intimate family in the entire system of elements and are grouped under the name "halogens" or salt formers (by derivation from the Greek). The first member of this family, fluorine, is the most chemically active element known; and fluorspar, and to a less extent cryolite, the chief sources of fluorine, are important commercial minerals. Fluorine occurs in nature chiefly in combination with sodium as common salt, but it also appears in other natural compounds in sea water, salt-well brines, and bedded deposits. In addition to common salt, various compounds containing chlorine (chlorides) have long been consumed by industry on a large scale, and within the last two decades that element itself has come rapidly into prominence as one of the leading industrial chemicals. Bromine and iodine, the two retaining members of the family, are less abundant in nature and less readily isolated and in consequence of their relatively high price have found few industrial uses, being consumed chiefly in medicine and in photography. Bromine, however, is now entering the industrial field to a considerable extent, due to the rapidly growing use of ethylene dibromide in anti-knock compounds for gasoline. The present paper is devoted to bromine and iodine, but in order to compre- hend the physical and chemical characteristics of these two elements (and hence their potential economic significance) it is convenient to consider them as members of the family series to which they belong. The family relationship of the halogens is illustrated by the following:4 (1) The similarity in the chemical and physical properties of the elements and their corresponding compounds is such that the prop- erties of any one member of the family can be said to summarize or rather to typify the properties of all the other members, although fluorine diverges a little in some of its properties. (2) The gradual transition of chemical and physical properties is such that if the elementa are arranged in order F, Cl, Br, I the variation in any particular property in passing from fluorine to iodine nearly always proceeds in the same order, and that is the order of their atomic weight. Taxing almost any property and comparing its magnitude in passing from the element fluorine to iodine, or from the fluorides to the iodides, a similar graiation will be observed. Thus, take the melting point of the cadmium, calcium, barium, sodium, or potassium salts, in degrees.

Nov 1, 1930

By P. M. Daling, C. A. Geffen

The objectives of this study were to examine a representative cross section of formal safety analysis techniques developed for the nuclear and aerospace industries, to recommend those methods that would be suitable for application to the mining industry, and to include those methods in a user's manual. Volume XI of this report, the user's manual, describes several methods that were determined to be immediately transferrable to the mining industry. The handbook gives detailed instructions on appropriate application and utilization of the methods. Other techniques will require further development before they can be effectively transferred to the mining industry.

Jan 1, 1983

"Investment in diamond exploration has been declining over the past decade, in spite of positive long-term industry fundamentals and a growing interest in diamonds as an investment category. The lack of new significant discoveries in recent years has eroded investor confidence, yet no new discoveries are possible without investment in exploration. Junior ‘mine finders’ have been the hardest hit. Their agility, tenacity, and appetite for risk are not sufficient to attract the funding required, even at the greenfield stage. Developing new discoveries into mineral resources can be crippling without solid financial support. Junior incubators could play a crucial role, especially at the project evaluation stage – but where are they? Alternatives to traditional funding mechanisms have become available, many still untested in the junior diamond exploration space. Valuable lessons can be drawn from the past and used to inform emerging new strategies. IntroductionDiamonds are the ultimate expression of love. Their ancient and timeless allure continues to influence consumer emotions and behaviours across continents, cultures and age groups. Analysts are predicting a sustained supplydemand shortfall in the years ahead which will trend diamond prices generally upwards. With positive long-term industry fundamentals, one cannot help but wonder why funding for diamond exploration and development projects is so scarce.Investment in exploration across commodities – including diamonds – has been declining for a number of years, reaching a historic eleven-year low early in 2017. The lack of major diamond discoveries in recent years has done little to strengthen the case for investing in diamond projects, yet no new discoveries can be made without investment in exploration.Global estimates of known carats in the ground stand currently at 2.5 billion carats, which equates to around 18 years of production at current levels of 140 million carats (mct) per annum. Sustainable replenishment of depleting diamond resources is possible only through the development of new discoveries. This is what junior explorers are best at – but they need investors to fund their evaluation activities from early in the project development continuum."

Feb 1, 2019

By Jim Glider, Noah Miner

The Gordie Howe International Bridge is a project to build a cable-stayed bridge and border crossing across the Detroit River. With a span length of 2,800-ft (853.4 meters), the Gordie Howe International Bridge will have the longest main span of any cable-stayed bridge in North America. Each tower has two legs that are supported by six drilled shafts each for a total of 12. The tower shafts are 9.84 feet in diameter (3-m) and extend well into bedrock. 17 each, 6.6 feet (2-m) drilled shafts were built to support the aging river bulkhead and replace shipping bollards. In addition to shallow groundwater fed by the Detroit River, artesian conditions at depth result in a water head that is approximately 17.2-ft (5.2-m) above surface. At 95-ft (29-m) below grade Dundee Limestone, of the Detroit River Group, is moderately weathered and fracture density decreases with depth. The Dundee Limestone strength ranges from 8-ksi (55.1-MPa) to 12-ksi (82-MPa) and may carry hydrogen sulfide in fractures. Working through casing that sticks three stories out of the ground is less than ideal, but was necessary to maintain a positive fluid head and prevent artesian-related quality issues. The sheer scale of the bridge forces required a load test configuration that could impart an equivalent static load of over 38,000,000 pounds (170-MN). A suite of QA/QC tests was developed to ensure the shafts would meet the project plans and specifications to include critical base cleanliness criteria. Interesting CSL and TIP results obtained highlight the strengths and weaknesses of each test method. Cleaning drilling fluids with a centrifuge allowed recycling of product and reduced exposure to environmental contaminate exposure. Having large construction equipment working next to the river presented challenges in working pad design. A driven pile system was developed to support high oscillator forces and protect the aging seawall.

Sep 8, 2021

By P. Rambalee

A multiple coal fired boiler house provides steam for utility usage in various production plants. Maintaining stable header pressure and boiler availability is of critical importance for downstream consumers. Advanced Process Control comprising of a G2 based expert system and Model Predictive Control was implemented to improve the boiler house performance. The results yielded improvements in the main header pressure stability, reduction in boiler saturation and significant saving in coal consumption. All information used for this document is from a published whitepaper written and led by Prevlen Rambalee (Anglo Platinum) and Gustaf Gous (BluESP) titled, ?Control and Stabilization of a Multiple Boiler Plant: An APC Approach?.

Jan 1, 2012

By R. C. Adams

This report describes the feasibility of mining the oil-shale deposits of the Piceance Creek basin in Colorado by an integrated open pit system. The study is based upon a comprehensive analysis of pertinent environmental, economic, and engineering factors. Ten mining cases are investigated, and the mine design and cost estimates for each case are presented in this report. Nine of the cases represent three cutoff grades, defining oil shale ore as equal to and above 15 gallons per ton (gpt), 20 gpt, and 25 gpt, at three ore production levels of 500,000 tons per day (TPD), 1,250,000 TPD, and 2,500,000 TPD. The tenth case is an alternate design of the 500,000 TPD production rate at the above 15 gpt cutoff grade. The report consists of Volume I, a technical and cost comparison of the ten cases; Volume II-Part I, a detailed explanation of the estimating methods used; and Volume II-Part 2, a more detailed discussion of the technical and cost features of the ten cases than is presented in Volume I.

Jan 1, 1976

By J. G. Pippenger

Rio Tinto Coal Australia (RTCA) developed the Meandu Mine in Queensland, Australia in 1983 to supply thermal coal to the adjacent and newly constructed Tarong Power Station (TPS). In designing the mine, RTCA selected Meandu?s best economic reserves for a 27-year life based on station owner Tarong Energy Corp.?s (TECs) estimated life for TPS. That 27-year plan changed dramatically in the early 2000s when TEC approved life extensions to TPS?s four existing units plus construction of a fifth unit. After reviewing Meandu?s remaining reserves, RTCA decided the nearby Kunioon reserve offered the more economic option for maintaining deliveries beyond 2010. Those plans changed again in 2007 when TEC chose to purchase the Meandu Mine and nearby reserves. TEC then selected Thiess Pty Ltd. (Thiess) to continue operating Meandu until the new mine at Kunioon could be developed. After assuming operation of the mine in 2008, Thiess began a review of Meandu?s remaining reserves and found considerable coal available with economic potential. Working jointly with TEC, Thiess performed several analyses on Meandu and subsequently the Kunioon coal reserves. The results changed TEC?s decision from expediting Kunioon?s construction to instead continuing Meandu?s operation for up to 15 additional years.

Jan 1, 2011

By V. L. SKITSKY

Geophysical Abstracts are published by the Division of Geophysical Explo- ration of the U. S. Bureau of Mines as an aid to those engaged in geophysical research and exploration. Inasmuch as geophysicists in the field may have little opportunity to consult libraries, the policy of the Division is to provide abstracts suffi- ciently informative in themselves to keep readers abreast of literature and patents published in the United States and abroad. - DISTRIBUTION. Abstracts 1-86 were issued as Information Circulars by the Burca of Mines; Abstracts 87-111 appeared as Bulletins of the Geological Survey; Abstracts 112-127 have been published as Information Circulars by the Bureau of Mines; succeeding issues will be resumed by the Geological Survey.

Jun 1, 1947

By Sara J. Davenport, Genevieve Morgis, J. J. Forbes

"This circular is part III of a series of papers reviewing the literature on air conditioning in mines, with particular reference to the health, safety, and efficiency of miners.4/ It deals with theoretical and practical methods of conditioning air in mines to correct or alleviate the health hazards described in parts I and II and discusses the results attained by some of the systems now in use in various-parts of the world.The principal conditions to be corrected or alleviated are the chemical qualities of mine air (especially when contaminated with toxic and noxious gases and dusts) and the physical qualities (abnormal mine temperatures and humidities) that emanate from various sources in underground workings. Air motion and barometric pressure are physical qualities also to be considered.From the standpoint of health, knowledge of the composition of the air, or atmosphere, in mines and other underground operations is of prime importance. Suitable control measures or plans of procedure to combat or eliminate the hazards from contaminants must be based upon accurate information obtained by the selection and use of proper methods of sampling and analyzing mine atmospheres (1).5/Conditioning air is one of the most essential factors to be considered in any underground workings, not only from the standpoint of health and safety but also with regard to efficiency and productivity. Without modern air-conditioning, the war's great demand upon the copper mines could hardly have been met, as the mechanical refrigeration cooled off sweltering holes in less than a month, whereas in the past it was standard practice to blow air through the tunnels for 3 years or so until they were cooled.This paper discusses methods of determining the chemical and physical qualities of mine air and their control. Briefly, the following points are presented:"

Oct 1, 1949

By D. Harrington

United States newspapers of 25 or 30 Years ago ran headlines every few weeks telling of some mine disaster. Each disaster was a first-page attraction for a day or so then was forgotten until the next sensational event, frequently another mine disaster, a few weeks later. Interspersed with the large mine disasters were the so-called ?snipping? mine accidents that caused the death of one or two mine workers. The summation of mine fatalities of all types usually exceeded 3,000 a year, and nonfatal accidents to workers in mines of the country approximated 250,000 annually. From 1906 to 1910, inclusive, there were 84 major explosion disasters (about 17 per year) in. United States coal mines. The resulting fatalities totaled 2,388 for the 5-Year period. These frightful catastrophes helped the number of fatalities in coal mines of the country to reach the enormous total of 13,288 for the 5 years, or an average of 2,658 per year.

Jan 1, 1940

By Shichang Liu, Hongli Jia, Zhaolian Wang, Maotang Liu, Ltd. Shandong Huate Magnet Technology Co., Fengliang Liu

"Introduce and promote a latest technology and equipment for magnetite. It’s featured of purifying concentrate, lowering tailing grade, high concentrate recovery rate and stable operation. HUATE® New Style Elutriation Electromagnetic Separator is an equipment to obviously upgrade magnetite. The slurry is fed into separation area through feeder. Generated by excitation coil, the working magnetic field distributes specially in separation area. Under the combined effect of the background field, excitation and demagnetic field and gravity, the mineral particles float downwards in the form of magnetic chains, and interact with the rising water. The gangue, non-magnetic particles, lean intergrowth,etc will be discarded as tailing via overflow tank and pipe. While the magnetic will be discharged from concentrate pipe. Its grade is 2%-10% higher than that of traditional magnetic separation equipment. It adopts the technologies of transformer oil cooling, alternative and uniform pulsation magnetic field controlling the tailing grade, larger drum feed-in device, more uniform umbrella scattering discharge and stabler output current, and realizes lower coil temperature raise, stabler magnetic field, more uniform discharge, effective isolation of weak-magnetic area from non-magnetic area, more obvious upgradation and recovery rate and lowering tailing mFe%. It’s more suitable to purify and thicken the high grade and ultrafine iron powder. Compared with traditional elutriation equipment, it adopts new technologies in removing impurities, operation, large-scale, process simplification, water-saving, remote control, etc. It optimizes the comprehensive beneficiation index, expands its application scope, reduces resource wastes and increases economic benefits.INTRODUCTIONMagnetite accounts for a comparatively great proportion in various iron resources. As it’s a kind of strong magnetic mineral, we must adopt the weak magnetic separation equipment in magnetic separation process to realize removing Si and lowering impurities. While it cannot do very well to use the common weak magnetic separation equipment in the final cleaning to remove Si and lower impurities. At present, the plants, adopting single magnetic separation process to realize cleaning and removing Si and lowering impurities, are in the minority. Most magnetite plants adopt the flotation separation process to remove Si, lower impurities and purify the concentrate. Though with stable indexes and high Fe recovery rate, the flotation process is very complicated, high-cost and with lots of environmental pollution. If adopting the weak magnetic separation equipment can realize removing Si, lowering impurities and the final cleaning, the magnetic separation process should be the primary choice."

Jan 1, 2016

By J. R. Arnold

The problem of recovering gold from a cyanide solution has been plaguing metallurgists since the cyanidation process was discovered in Glasgow, Scotland.1 The "perfect" method has never been found and this paper will not purport to fill that gap. But we, at Gold Fields, feel that we have developed a workable, cheap and efficient method of producing a refinery - ready product that has several distinct advantages over conventional electroplating techniques. The Gold Fields replating system is presently being used at their Ortiz and Mesquite operations. In short, the system electroplates the gold out on stainless steel wool, instead of mild steel wool as is usually done, then replates the gold by reversing the current onto stainless steel plates. By doing this the steel wool can be reused many times, the gold can be scraped off the plates cleanly and quickly, the operating costs are reduced and the slag production is greatly reduced.

Jan 1, 1986

Bailey, Lewis Newton, Master Engineer, Senior Grade, 4th Regiment, U. S. Engineers, Headquarters Company, died of pneumonia at Camp Merritt, N. J., on April 30, 1918. Baird, Louis, Lieut., Royal Field Artillery, British Army, died on the battlefield in 1915. Cobeldick, William Morley, Royal Engineers, died from gas poisoning on October 7, 1915. Dougall, Ralph, killed in action. Evans, Alfred Winter, Lieut.-Col., New Zealand Rifle Brigade, D. S. 0., D. C. M., killed in action on October 12, 1917. Gorman, Thomas C., Lieut., Canadian Engineers, killed in France, Mar. 18, 1918. Hague, William, 1st Lieut., Engineer Officers' Reserve Corps, died in active service. Hall, William T., Capt., Royal Flying Corps, killed in action. Heine, Bernhardt E., Lieut., Aviation Service, killed at Fort Sill, Okla., Aug. 10, 1918. Irving, John Duer, Capt., 11th Engineers, A. E. F., died while on active service in France on July 26, 1918.

Jan 9, 1918

By Gordon T. McKenna

"Syncrude Canada Ltd. is developing new concepts in lease-closure landscape design for its Oil Sands Leases 17 and 22 in northeastern Alberta. Closure planning is becoming an integral part of the planning cycles and of the lease operation. By incorporating closure planning into the day-to-day operation, the company will achieve acceptable lease closure in an economical manner. Ultimately, Syncrude will achieve lower operating costs through innovation in mine planning and a reduction in residual liabilities.New concepts being evaluated for lease-closure landscape design include: designing for closure, use of landforms and natural analogs, self-armouring bouldery ground, robustness in design, landform grading, terrain analysis of reclaimed land, geotechnical hazard assessments, choices in closure design timeframes, passive maintenance, determining post-closure monitoring goals, engineering tailings, engineering other substrates, use of test plots and field demonstrations, geomorphologic monitoring of reclaimed lands, defining closure goals, and visiting other mines. These concepts are being formalized under the new discipline of Landscape Engineering."

Jan 1, 1996

By A. Hasselbring

Sub-Level stoping was used in this country at least as early as 1912, at the Magpie mine in Michipicoten. The fundamental principles of the system are the same wherever it is used, but modifications have been adopted in the Michigan iron mines and in several Canadian mines. It is a system whereby a suitable body of ore may be developed quickly and worked cheaply, with a low initial expense, and by miners of quite ordinary ability. The basic method, described in the following pages, may be modified to meet conditions where one or more factors are not in accord with normal sub-level stoping requirements. In suitable ground, sub-level stoping is probably the most satisfactory method yet devised for underground hard-rock mining. It is so simple, straightforward, and safe that no special training of a crew is necessary. Any miner capable of drifting and raising can carry on the work necessary for sub-level stoping after the shaft has been sunk. The method is suitable, however, only for reasonably wide ore-bodies, the minimum width of ore to which it can be economically applied being somewhere in the neighbour-hood of thirty feet. The development programme is simple. Assuming, for purposes of illuslustration, an ideal ore-body, two thousand feet long, dipping nearly vertical, and varying in width from forty to a hundred feet, this programme would be as follows. The shaft should be sunk on the footwall side about sixty feet outside of the ore-body and near its centre. Levels are then established at suitable intervals, usually 125 feet. On each level, a cross-cut is run to the ore-body, and there a main-haulage drift is driven in either direction to the end of the ore. Cross-cuts are then run at 25-foot intervals, so that ore-chutes can be spaced about 25 feet centre to centre each way. It is not necessary that these cross-cuts be extended to the walls of the ore-body, if the position of the walls is known; they are extended just far enough to make room for the correct location of the chutes.

Jan 1, 1934

By C Hamilton

Stawell Gold Mines (SGM) is an underground mining operation located in Victoria, Australia. The mining method employed is long hole retreat stoping, utilising up and downholes and artificial concrete pillars. Stawell is currently mining the Golden Gift and Magdala orebodies.Access to the Magdala and Golden Gift deposits is via 6.0 m wide by 5.5 m high declines developed at a gradient of one in eight to one in seven from the surface to a depth of 1500 m, with a planned depth of 1650 m. From the declines, cross cutting drives are developed to intersect the orebodies. Orebodies in the Gift system are discrete lodes which are generally mined from a bottom up centre retreat to minimise geotechnical stresses.Ore development fronts are currently located between 1000 m and 1500 m below surface, with all ore being hauled to the surface using a fleet of 60 tonne underground trucks. With the use of conventional pyrotechnic long period (LP) delays, broken rock of combined ore and waste is thrown 10 m from the face and the materials hauled to the surface. The majority of the mullock from development is consumed in the underground as backfill.With the use of Orica Mining Services eDev™ Electronic Blasting System for Tunnelling, the waste is thrown up to 40 m from the face, while majority of the ore is left 5 - 10 m from the face, effectively segregating ore and waste. This enables significant recovery of gold values with minimal loss and significantly reduced dilution. By using this technique in ore drives with a 30:70 waste to ore ratio, SGM is able to haul 24 000 tonnes less mullock to the surface annually. Resue mining is applied to narrow vein headings and gives a 40 per cent grade increase at the faces as well as increasing the economic footprint of development. This will also contribute to an improved grade profile for the year from 3.98 - 4.16 g/t Au and allow extra capacity for ore haulage from stoping and for milling.This paper describes the application and the successful blast outcomes achieved using the eDev™ Electronic Blasting Systems for resue mining at SGM. Results to date, since commencement in March 2010, have been achieving significant benefits in terms of ore grade as confirmed by geologists grab sample grades. Face advance have also shown improvement with better breakage of perimeter holes giving improved face profile. These benefits are delivering increased productivity and safety performance when compared to other resue firing techniques.

Mar 21, 2011

The Government of New South Wales has granted approval for Hunter Valley Aluminium Pty., Ltd" and Alcan Australia Ltd. to proceed with the building of an aluminum smelter at Lochinvar and the expansion of a smelter at Kurri Kurri. Construction of the smelters is expected to start as soon as the consortium is finalized in early 1982. The smelters are part of a plan to increase Australia's aluminum capacity fivefold to 1.5 million tons by the mid-1980's. CHILE Construction of a $61 million lithium carbonate plant in northern Chile will be started in early 1983 by Sociedad Chilena del Litio Ltdao Production is scheduled to begin in 1984 with an initial capacity of 6,350 tons of lithium carbonate produced from a brine deposit. The firm is owned 55% by Foote Mineral Company, of Exton, Pennsylvania, and 45% by Corporacion de Fomento de la Produccion-CORFO.

Jan 1, 1982