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By George Watkin Evans

The United States Geological Survey has estimated 1 that the State of Washington contains 11,412,000,000 tons of bituminous coal and 52,442,000,000 tons of subbituminous coal, in beds more than 14 inches thick. As the present rate of production is about 4,000,000 tons a year, Washington apparently contains coal enough to supply Pacific coast markets for many years. The character of the coal beds of Washington renders the production of clean coal very difficult, and a considerable proportion of the output is washed before it is marketed. In 1915 Washington ranked fifth among the States in the amount of coal washed, though only twentieth in total output. In that year 37.9 per cent of the coal produced in the State was treated in surface cleaning plants. On account of extensive folding and faulting of the coal measures, mining in Washington presents many difficulties; therefore a description of the methods employed at some of the mines may be useful in planning operations in other regions, and is presented in this bulletin. The coals of Washington differ in quality, ranging from true lignites in Cowlitz County in the southern part of the State to anthracites in the Mount Baker district of Whatcom County, in the north~ rn part. Most of the output consists of subbituminous and bituminous coals, the latter including both coking and noncoking varieties. Analyses of the coals of the State and descriptions of the beds from which the samples were taken have been printed in publications of the United States Bureau of Mines.2 Details of coal beds and analyses of the coals of King, Kittitas, and Pierce Counties have also been published by the Washington Geological Survey; 3 and most of the coal beds of the State are described in some detail in a bulletin of the United States Geological Survey.4 In 1918 mining was in progress at 72 mines in the State 4a; 46 of these mines each employed more than 10 men underground. These mines were distributed as follows: Thurston County, 1; Lewis County, 7; Kittitas County, 14; King County, 16; Pierce County, 6; Skagit County, 1; and Whatcom County, 1. During that year a total of 5,847 men were employed, 4,172 underground and 1,675 on the surface. The average number of days worked in the State was 275, and the average yearly output per man was 706 tons. Coke is made only in Pierce County by four companies, which have a total of 341 beehive ovens. In 1918 they produced 93,699 tons of coke. Up to 1919 mining machines were little used in the State. In 1917 only 6.61 per cent of the coal :produced was undercut by machines. In that year 58.95 per cent of the coal was mined by hand, and 34.44 per cent was shot off the solid. The explosives used were as follows: Black powder, 36.6 per cent; dynamite, 38.l per cent; and permissible, 25.3 per cent. The State of Washington is divided naturally into two parts by the Cascade Mountains which extend north and south somewhat west of the middle of the State. The coal areas east of the range will hereafter be referred to as eastern Washington-though nearly all of it is west of the middle of the State-and that on the west side as western Washington. The geographical distribution of the coal fields is shown in Plate I. Exploration of the State has not been exhaustive enough to preclude the possibility of discovering, besides the foregoing, other districts that contain deposits of coal in commercial quantities.

Jan 1, 1924

By W. Collingwood, K. V. Raj, S. Bandopadhyay

In the mining industry, computational fluid dynamics (CFD) modeling is used extensively to simulate air flow in underground mines. CFD modeling of pollutant transport in openpit mines is relatively new. Modeling the actual pit geometry of an openpit mine and the open domain is complex. The complexity is primarily due to the faceted geometry of an openpit mine with its numerous associated sharp features. Important issues that are not considered carefully at the geometry level are generally propagated to the subsequent processes. Several challenges and pitfalls are encountered in modeling pollutant transport in openpit mines. These challenges and pitfalls are related to the geometry, meshing, boundary conditions and turbulence modeling parameterization. An appropriate mesh selection is critical. A detailed discussion of the meshing of the domain of an openpit mine is presented in this paper. The selection of an appropriate turbulence model, such as kappa-epsilon (κ-ε), large eddy simulation (LES), Reynolds stress model (RSM), etc., to obtain the best possible solution is equally significant. This paper discusses the various challenges in modeling the pollutant transport process in an openpit and some of the approaches adopted to address these challenges.

Jan 1, 2013

By CIM Standing Committee

The CIM Definition Standards on Mineral Resources and Reserves (CIM Definition Standards) establish definitions and guidance on the definitions for Mineral Resources, Mineral Reserves, and mining studies used in Canada. The Mineral Resource, Mineral Reserve, and mining study definitions are incorporated, by reference, into National Instrument 43-101 – Standards of Disclosure for Mineral Projects (NI 43-101). The CIM Definition Standards can be viewed at mrmr.cim.org. Readers should be aware that reports written by persons issuing technical reports that disclose information about exploration or other mining properties to the public in Canada are governed by a number of securities regulations.

May 10, 2014

By BHAMIDIPATI S. SASTRY, SRIVATSAN J. SRIDHARAN, ANMAYA NAIK, ASIF AHMAD, ADITYA PANDEY

Wet kata cooling power (WKCP) measured using a kata thermometer is a well-known heat stress index in mining industries. Although over the years several researchers have proposed different heat indices and indicated the limitations of the kata thermometer, it is still being used in many areas, especially in the South African gold mining industry, mainly because of its simplicity and rapidity of assessment. This paper presents a comparative analysis of the newly developed empirical expression for WKCP, and some of the more prevalent empirical expressions. The analysis presented based on a regression technique aims to assess the disagreement between model predictions and actual measurements. It is found that the WKCP expresses bioclimatic interaction quite well under the specific parameter of interaction that explains the harsh thermal environment and air condition, such as metabolic activity, the person’s clothing, and the velocity of the air in which the person is working. The statistical analysis shows that the WKCP exhibits significant estimates to thermal stress under lower air velocities, light clothing, and higher metabolic activity rates.

By Smortchevskyk N. J.

THIS paper describes the electrical features of the locomotive now (August, 1962) under construction for Craigmont Mines. Intended for non-specialists, it avoids details of design and calculations interesting to electricians only. The paper is divided into three sections. The first deals very briefly with the mine layout and with operating conditions -existing and expected. Reference is made to economic considerations leading to the selection of the type and size of locomotive, as well as to traction diagrams and the calculations. This material is not included in the paper because of its length and because it does not represent anything new. The second section deals with engineering and economic considerations and shows, in some detail, why the A.C. system was chosen. The third section describes the basic components of the locomotive, including the voltage regulator, the rectifiers, the control arrangement and the filter, and deals with considerations affecting the selection of their rating and design. A concluding sub-section describes, very briefly, the track and trolley details and the power distribution switchgear.

Jan 1, 1963

By S. A. McGhee

Introduction ASARCO's Ray Operations include an open-pit copper mine in the Mineral Creek Mining District of Pinel County. The district is located in east central Arizona, 132 km (82 miles) southeast of Phoenix, AZ, and 126 km (78 miles) north of Tucson, AZ. The mine lies 8 km (5 miles) north of the Gila River in Mineral Creek Valley, between the Tortilla Mountains to the west and the Dripping Springs Range to the east. The rich copper deposits of the Mineral Creek mining district were first noted by a US Army Officer in 1847. The Ray Copper Company was the first major operation in the area. The company was named after the Ray mining claim, which was one of the earliest recorded claims. After decades of sporadic and unsuccessful mining ventures, the Ray Consolidated Mining Company was formed in 1910. The company introduced one of the first successful block caving operations in the world. In 1933, the Kennecott Copper Corporation acquired the Ray Consolidated Mining Company and continued operation of the mine under the same name until 1943, when the property was renamed the Ray Mines Division of Kennecott. Underground mining continued until 1955, when the mine was converted to an open pit operation. In November 1986, ASARCO Inc. purchased the Ray Mines Division and related facilities from Kennecott. The purchase also included the Hayden concentrator and the Ray Smelter, located approximately 32 km (20 miles) from the Ray Mine. This paper summarizes the 54,400 tpd (60,000 stpd) in-pit crusher and overland-conveying system and the 24,200 tpd (30.000 stpd) copper SAG concentrator and tailings disposal system constructed at ASARCO's Ray Complex - Ray Operations. General description of facilities The Ray concentrator includes a sulfide SAG concentrator, a "relocatable" in-pit primary-crushing plant and overland-conveyor system, a concentrator tailings-disposal system and plant ancillary facilities, The major elements of the project include: • A relocatable Fuller-Traylor in-pit 1524-mm (60-in) x 2261-mm (89-in) primary gyratory crusher at the 442 m (1450 ft) mine elevation. The crushing plant has a nominal capacity of 54,400 tpd (60,000 stpd) of sulfide ore. • A 1524-mm (60-in) wide x 1253-m (4110-ft) long overland belt conveyor, which runs from the in-pit crushing facility to a transfer station serving both the Ray Concentrator and the existing Hayden concentrator railroad load-out facility. • A 1524-mm (60-in) wide x 152-m (500-ft) long stackerbelt conveyor, which delivers a nominal 27,200 tpd (30,000 stpd) of ore from the transfer station to a 23,600 t (26,000 st) live-capacity coarse-ore stockpile serving the Ray Concentrator. • A nominal 27,200-tpd (30,000-stpd) concentrator, including semiautogenous grinding, flotation, copper concentrate filtration and associated plant ancillary facilities. • A tailings disposal system. Flotation tailings are pumped from the Ray Concentrator to a 122-m (400-ft) diam. thickener, located 4.8 km (3 miles) southeast of the Ray Concentrator site. The thickener overflow is pumped to two 76.2-m (250-ft.) diam. concrete process-water reservoirs. The thickener underflow, at 45% solids, is pumped to a new tailings disposal site located at Elder Gulch. • An HDPE-lined temporary-containment area to collect material from Ray Concentrator plant upsets and local storm-water run-off from a 100-year, 24-hour rain event. •A reclaim-water system from the Elder Gulch tailing pond area to the Ray Concentrator. • A 610-mm (24-in.) diam. x 31.9-km (19.2 mile) long fresh-water pipeline from the Hayden fresh-water-well field system to the Ray Concentrator. The overall process design criteria for the new Ray Concentrator is based on a nominal throughput of 27,200 tpd (30,000 stpd) of ore at 90% plant availability. However, based on the maximum performance capacity of the installed grinding equipment, it may be possible to achieve a sustained operating level in excess of 36,300 tpd (40,000 stpd) when processing soft ores. The balance of this paper will cover the major process systems including:

Jan 1, 1995

By James M. Link

Underground coal mining is the most hazardous industrial occupation in the United States.. Haulage accidents in underground coal mines contribute substantially to the occupational hazards of this type of work. In an effort to improve mine safety, a completely hydraulic transport system has been designed to move coal from the mine face to the preparation plant. The capital investment for the hydraulic haulage system is great, and the size of the mine developed for this study is large. Mine production for the conventional haulage mine is 1. 1 million tons of clean coal per year, while the hydraulic haulage mine will produce over 1.6 million tons of clean coal per year. Safety statistics for a number of mines of this size are shown.

Jan 1, 1975

By L. L. Hirst

In 1944, the 78th congress of the United States enacted Public Law 290, which directed the Secretary of the Interior, acting through the Bureau of Mines, to furnish industry with basic information and cost data for the development of a synthetic liquid fuels industry. Recently published information with respect to the cost of synthetic liquid fuels processes indicates a wide variation in estimated results. To clarify the results and inconsistencies for the hydrogenation of coal, the Bureau of Mines has prepared preliminary designs and calculated detailed investment costs from which the operating costs to produce 30,000 barrels per day of liquid products, mainly gasoline, by coal hydrogenation were obtained.

Jan 1, 1949

By S. D. Dladla, S. Ramsamy

The majority of the tailings dam operations in South Africa will be required to comply with the new Global Industry Standard on Tailings Management (GISTM) within the next one to three years, depending on the dam classification and the requirements of the respective investors and insurers. With up to 72 auditable requirements, the implementation of the Standard needs careful planning and prioritization. This paper focuses on the practical steps to GISTM compliance for tailings facilities in operation in South Africa. The discussions are based on current practices, South African regulations, and industry standards requirements. The possible changes in dam classifications and the associated requirements are presented.

Jun 2, 2022

By A. A. Berk

The Bureau of Mines devised a test nipple for the field study of corrosion in the condensate-return lines of Federal heating plants. Corrosion surveys, made with this device, showed that the deterioration of the piping was caused principally by carbonic acid in the steam condensate. Corrosion problems were brought under control when the carbonic acid concentration in the condensate was decreased. In many instances, this was effected by decreasing the total carbon dioxide content of the feedwater; in others, the condensate acidity was neutralized with volatile, alkaline chemicals. Filming treatment with octadecylamine, reported successful in controlling return-line corrosion in industry, was much less effective in Federal area-heating plants. Laboratory study by the Bureau disclosed that octadecylamine is unstable in heating systems. Analytical methods were developed for this chemical and its degradation products in heating-plant condensate. Field surveys, in using these methods, confirmed the instability of the filming material. Laboratory tests showed that the degradation products are not useful film formers. Since filming treatment has little effect on condensate corrosivity, the piping was corroded where it was not coated by the treatment chemical.

Jan 1, 1962

By Michael P. Amsden

"THE ECSTALL CONCENTRATOR is situated adjacent to Highway 101 and the Ontario Northland Railroad, 15 miles east of Timmins, Ontario. Ore is delivered to the concentrator by rail from the mine, which is 17 miles northwest of the plant. Power and fuel are obtained from the hydro and natural gas lines which pass close to the plant site. Water is obtained from the Frederickhouse River, 6 miles east of the concentrator. The main concentrator building is a large structure 500 by 640 feet by 90 feet high and contains facilities for fine crushing, crushed ore storage, grinding, flotation, tin recovery, concentrate handling and reagent handling. Located in the same building are the machine shop, warehouse, metallurgical laboratory, pilot plant, men's change room, sample preparation area and an assay laboratory. The general concentrator layout is shown in Figure 47. Originally designed to handle 9,000 tons per day, the concentrator now treats 10,000 tons per day. Two different ore types are processed by selective flotation in three individual circuits to recover copper, lead and zinc concentrates. In 1973, another circuit was added to recover pyrite and tin concentrates from the combined zinc tailings of the three main circuits."

Jan 1, 1974

1. Domestic Production and Use: In 1984, 12 companies operated 27 primary aluminum reduction plants, with 3 firms accounting for 57% of production. Washington, Oregon, and Montana accounted for 35% of the production; Indiana, Kentucky, Missouri, and Tennessee 25%; Alabama, Arkansas, Texas, South Carolina, and North Carolina 20%; other States 20%. Based on published producer prices, output of primary metal in 1984 was valued at $7.2 billion. Aluminum consumption by 25,000 firms was centered in the east-central United States. Packaging accounted for an estimated 35% of domestic consumption in 1984, transportation, 20%; building, 18%; electrical, 9%; consumer durables, 8%; and other uses, 10%.

Jan 1, 1985

By Oliver Bowles

PRICES of quartz sold in the United States in 1938 ranged from $1.15 to $36,000 a ton. This startling variation was due simply to the differences between glass sand and rock - crystal, materials that are virtually the same in composition. It illustrates the complexities in qualities, uses, and values of industrial minerals. It is generally stated that mineral deposits are exhaustible resources which can never be replaced when depleted. This statement is no longer true with respect to certain industrial minerals now recovered in increasing quantities from that most inexhaustible of all sources of supply, the ocean. Salt has long been obtained from sea water, particularly on the Pacific Coast, and reference was made a year ago to the large bromine recovery plant at Wilmington, N. C. Now the Westvaco Chlorine Products Corp. is operating a large plant at Newark, Calif., having a capacity sufficient to recover daily from the ocean raw materials that will produce 60 tons of various magnesium products. Lime is used to precipitate the magnesia from salt-water bittern. The products are chiefly magnesium carbonate for chemical uses, periclase and other refractories, and oxychloride cement for flooring.

Jan 1, 1939

By P. Nos, L. Kolbeinsen, M. W. Kennedy, A. Filzwieser, R. T. Jones, A. MacRae

Modern furnace designs often incorporate extensive use of cooled elements to achieve long campaign lives at high operating intensities. However, contact between water and high temperature fluids can result in powerful Boiling Liquid Expanding Vapour Explosions (BLEVEs). Therefore cooling such elements with water carries inherent risks when used under slag and particularly below molten metal or matte. Alternative cooling media exist that can reduce or eliminate the risk of BLEVEs. These media are analysed and discussed in the context of deeply cooled furnace elements. Important factors in selecting alternative coolants are explored including: critical heat flux, thermal limits, toxicity, flammability, unit cost, etc. Key cooling system design criteria are reviewed in the context of both traditional and alternative coolants. Results of Computational Fluid Dynamics are presented for an example tap-block cooler design using a number of selected coolants. Research needs to advance the safe use of alternative coolants are presented.

Jan 1, 2015

By John F. Dougherty

Recently, there has been much debate as to the relevance of reporting financial results using the conventional accounting systems, which is based on historical costs, during a period of rapid inflation. In the following paragraphs , the symptoms, if not the causes, of inflation, its detrimental effect on the financial soundness of business in general and the financial reporting changes being advocated to overcome perceived weaknesses in the present financial reporting system in accounting for the effects of inflation will be reviewed. Finally, a course of action as a sound approach to the financial reporting problem will be recommended.

Jan 1, 1978

By A. P. I. Popoola, D. O. Okanigbe, A. A. Adeleke

In view of the steady depletion of primary sources of copper and the increased global demand for refined copper, it becomes necessary to explore some secondary sources for possible extraction of copper. The waste copper smelter dust (CSD) is a rich secondary resource for copper as shown by the chemical composition of the South African Palabora coppers smelter plant CSD that assayed 18.02, 13.36, and 3.4 wt% copper, iron and sulphur, respectively. Studies on CSD have focused majorly on either dust characterization or treatment, while hydrometallurgical extraction without pretreatment and with pretreatment using techniques such as oxidative roasting are also considered quite attractive. The challenge of iron dissolution during the leaching stage in these processes necessitates adequate purification of the leach liquor before the extraction of the metal as nano-particles. Hence, this review examined the theories relating to the characterization and treatment of CSD for copper recovery as nanoparticles; with factors having a bearing on the treatment process such as kinetics considered with the aim of providing scientific basis for the research.

Mar 1, 2017

By L. D. Tracy

"IntroductionOne of the problems which the coal-mining industry must solve in the next few years is the redaction of its ever-increasing timber bill. This includes pit posts, mine tees, timber sets, and brattice boards. As an example of this increase, the following table of timber prices from the records of a coal company in western Pennsylvania, in a district where the supply of most of the different kinds of timber used can be shipped from points within the State, is self-explanatory: Present conditions seem to indicate the continued upward trend ox the cost of mine timber, although the regrettable calamity that has visited the chestnut timber in Pennsylvania may temporarily hold the price of some types of mine timber on a level basis. On account of the chestnut blight, many farmers will undoubtedly begin to convert their chestnut trees into timber before they become a total loss. This may provide, for the time being, a sufficient supply of mine timber to check the steadily rising prices.The local lumber producers are turning their attention to the production of the larger sizes of timber and lumber on account of an unfavorable price on mine ties. From the foregoing table, it is seen that the average advance in the price of ties during the period 1914 to 1920 is 52 per cent, while timber sets and mine car plank increased in value 60 per cent. Amore striking illustration is the fact that a 6 by 8 inch by 6 foot tie sells for 42 cents or at the rate of $17.50 per 1000 board feet; yet mine car plank and timber sets have a value of $48 per 1000 feet, an advantage of $30.50 in favor of the heavier timber.The supply of coal in Western and Central Pennsylvania will last for a long period and it is for the possible future demand for timber that the coal companies must provide. While steel, concrete, and other materials may, in many cases, prove an acceptable substitute, there is no doubt that timber will always be in demand."

Nov 1, 1926

By G McCullough, J Bassan, d P. Knights, C T. Farrelly

By 2045, carbon-neutral mines will be economically producing products that are vital for the world’s transition to renewable energy. After overcoming significant technical challenges (and the investment of significant capital), leaders have successfully eliminated the use of diesel and other fossil fuels by introducing a wide range of new decarbonisation technologies. These leaders will be reaping the benefits of lower production costs (resulting from elimination of diesel), stable and predictable operations, and easier access to capital for their future projects. This paper describes a future scenario of how a net zero carbon and zero-entry mine could operate by taking maximum advantage of technologies in development or already proven in other industries. Some miners have been unsuccessful in their efforts to reach decarbonisation targets. Instead, they have been forced to close or offload their assets to be acquired by operators with better sustainability credentials, or, in some cases, to indigenous or community-based enterprises with vested interest in making operations viable and sustainable. Regardless of ownership structure, all successful mining operations will have fostered strong and positive community relations that bring education, health, security and economic development opportunities to the communities while respecting their traditions, land-uses and culture. As shallow, easy to mine deposits have become scarce, the majority of new mines are underground. Advancements in electric underground technology and the feasibility of ‘zero entry mining’ (with no personnel in active mining zones) has made it increasingly possible to economically operate underground mines, even at shallow depths. The newest mines have a near zero footprint on the surface, produce no harmful by-products, and are employing in-place or in situ methods of extraction that are efficient and low impact. Surface land-uses, such as agriculture and renewable energy generation, continue in the immediate vicinity of the mine, with no significant ground disturbance, community impact or environmental footprint.

Sep 1, 2024

By Paul D. Tomlingson

An effective maintenance program ensures the adequate availability of production equipment. In turn, this availability enables production to maximize utilization and successfully meet production targets. An overall production strategy is necessary to draw all departments toward this common effort. Only then will production targets be met. From the maintenance view this means that production must comply with PM and repair schedules. Purchasing must supply parts and materials on time. Mine engineering must not overwhelm maintenance with non-vital construction. Accounting must provide correct, timely cost information - - etc. This strategy - - its content, effectiveness and enforcement is the responsibility of the mine manager . . . his alone. This paper describes a successful approach to maintenance within this strategy.

Jan 1, 1979

By Erik Sherer

Indonesia is poised to become a major player in the Pacific Rim thermal coal markets. Although the colonial Dutch developed numerous coal mines in the late 1800's for steamship bunkers and domestic fuel, Indonesia's coal industry has only recently begun to actively participate in the growing global marketplace. This export coal is primarily the result of the commercial development of coal mines in eastern Kalimantan by foreign contractors. From virtually no coal exports in the late 1980?s, Indonesia's coal industry has increased its exports to approximately 15 million metric tons (Mmt) in 1992. In 1992, Indonesia was the world?s sixth largest exporter of steam coal, By the year 2000, Indonesia projects that it will supply approximately 25 percent of the seaborne thermal coal requirements of the Pacific Rim countries. Although limited quantities of this coal may enter the European and U.S. markets, high qualities, low production casts, and favorable transportation rates will make Indonesian coals very competitive in the rapidly growing Pacific Rim markets. This study examines the Indonesian coal mining industry and compares it to the U.S. coal mining industry. This report is the sixth in a series of coal exporting country studies requested by the House Appropriations Committee. Previous studies examined the Colombian, Canadian, Australian, South African, Polish, and Venezuelan coal industries.

Jan 1, 1994