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By Seth T. Reese

THE INJURY DATA and experience at coke ovens in the United States for 1952 are presented in this bulletin under the following general sections: (A) General injury experience: Tables 1 to 9: Contain current and comparable data on operating statistics, number and classification of injuries, frequency rates, and accident agencies involved in causing injuries. Data are given for the industry as a whole, for each type of oven, and for the States in which coke is manufactured. (B) Selected injury experience: Tables 10 to 15: Contain comparable injury data in the coking industry covering 5- and 10-year periods on the number of injuries, accident agencies, and severity of injuries. (C) Historic injury experience: Tables 16 to 19: Contain data on the number of injuries, frequency rates, and employment at coke ovens from the earliest records through 1952, Operating statistics from 1929 through 1952 are given in table 19.

Jan 1, 1955

By Kazuteru Tozawa

Surface tension, density and viscosity coefficient of acidic copper sulfate solutions simulating electrolyte solution for electrolytic production of copper have been measured and are summarized as a function of the solution composition and temperature. Nickel sulfatc is taken to be a representative coexisting sulfate that affects the physical properties of the copper sulfate electrolyte solution. The sulfates in the solutions, including sulfuric acid, increase the physical properties under consideration. Gelatin, representing organic additives for electrolyte solution, was found to sensitively affect the surface tension of the solution at low concentration of up to 200mgIL. The surface tension was markedly lowered by the addition of gelatin and the increasing concentration of gelatin led to a more pronounced decrease in the observed values. The surface tension gradually increases with time after addition of gelatin and the increase is enhanced by higher acid concentration and higher temperature. The observed change in the surface tension is considered to reflect the preferential adsorption of gelatin to the bubble-solution interface and the decomposition of gelatin due to hydrolysis to form various molecules having smaller molecular weights.

Jan 1, 2003

By B. R. MacKay

Introduction During the past six seasons the writer has been engaged in semi-detailed investigations on the coal areas lying along the front of the Rocky mountains between the Brazeau river and the Smoky River Coal Reserve (see Map, Figure 1). The purpose of this paper is to present some observations pertaining to the stratigraphy and structure of the district, touching especially upon the lithological units into which the Lower Cretaceous sediments have been divided, the thicknesses of the formations at different localities, the number, thicknesses and horizons of the principal coal seams, and the structural conditions which exist in the various fields.

Jan 1, 1930

By Noreen Tarac, Pablo Forgoso, Philipp Schober

A multiple use storage facility building is being developed in the Philippines on a peninsula that was reclaimed in the 1990s without any soil treatment. The subsoil now consists of loose to medium dense silty sand underlain by a soft to medium stiff clay. A liquefaction assessment by analytical methods have shown that the loose to medium dense silty sand yields a high potential for liquefaction and lateral spreading during pthe design level seismic event. To mitigate the risk of liquefaction and lateral spreading, as well as assure the slope stability of the shoreline, a solution utilizing a combination of ground improvement techniques by means of a Mixed-In-Place (MIPTM) Lattice Grid Wall and Stone Columns was developed and successfully executed. For the detailed seismic design, a Finite Element 3D analysis was undertaken to simulate static and dynamic actions on the buttress wall. The liquefaction assessment and settlement calculation were carried out based on analytical design approaches. For the execution of the Lattice Grid Wall, the Mixed-In-Place (MIPTM) method developed by BAUER Spezialtiefbau GmbH was applied. The stone columns were installed using the Wet Top Feed method.

Sep 8, 2021

By E. D. Gardner

Open-cut mining of copper ores in the western United States is a relatively new industry. At first the mining methods were mainly adapted from those used at open-cut iron mines and at quarries, but now efficient practices that are more suitable for the copper deposits have been developed. The pioneer in this field is the Utah Copper Co., of Bingham, Utah, which deserves great credit for working out much of the early procedure. Stripping began at that mine in 1906, and the large Garfield concentrator was put in commission in 1908. Next in order of development were the Nevada Consolidated Copper Co., at Ely, Nev. ; the Chino mine of the Ray Consolidated Copper Co., at Santa Rita, N. Mex. ; the New Cornelia Copper Co., at Ajo, Ariz. ; the Sacramento Hill mine of the Copper Queen Branch, Phelps Dodge Corporation, at Bisbee, Ariz.; and the open cut of the United Verde Copper Co., at Jerome, Ariz. The Sacramento Hill mine began to produce in 1923, and the United Verde open-cut mine has produced ore mainly in connection with stripping. The writer visited the Utah Copper mine in September, 1923; the Nevada Consolidated in August, 1923; the Chino in July, 1924; and the New Cornelia, the Sacramento Hill, and the United Verde open cut at various times during 1922, 1923, 1924, and 1925, mostly in connection with other work.

Jan 1, 1927

Pilot-Scale Study of Deep Cone Thickener for Phosphatic Clay Dewatering

Sep 13, 2010

By S. J. Rodgers

MSA Research Corporation, Division of Mine Safety Appliances Company, was awarded a contract to conduct a survey of past and present methods used to control respirable dust in noncoal mines and ore processing mills. The survey covered information reported in mining journals, and U.S. Bureau of Mines Circulars, dust inspection reports, on-site evaluation of dust control methods and systems, and contact with manufacturers of dust control equipment. Both surface and underground mining operations were visited. Fifty mines and 51 processing plants were included in the survey. Dust control methods for the following types of ores or mines were studied: [ ]

Jan 1, 1974

By H. F. Yancey

This report, dealing with the separation of coal from its associated impurities by means of a pulsater-type jig, continues the series of reports that have been issued by the Bureau of Mines, in which detailed study has been made of the efficiency and mechanism of separating coal and impurities in various coal-cleaning appliances. The previous reports have dealt with the piston jig, coal-washing table, pneumatic table, and Baum-type jig. Such studies of the separation accomplished by any form of concentration device are essential and necessarily preliminary to any intelligent attempt to improve the performance of such equipment Object and Plan The pulsator-type jig was developed recently by G. A. Vissac. Although two articles(2) describing plants using this typo of cleaning unit appeared in 1936, both dealt principally with plant design and layout rather than with plant performance The object of the stork described in this report was to determine the efficiency of the separation made by the pulsator jig on a sized feed, the specific gravity at which the separation between coal and impurity was effected, and the influence of the specific-gravity composition of the coal on the character of the separation made.

Jan 1, 1938

By H. F. Yancey

This report, dealing with the separation of coal from its associated impurities by means of a pulsator-type jig, continues the series of reports that have been issued by the Bureau of Mines, in which detailed study has been made of the efficiency and mechanism of separating coal and impurities in various coal-cleaning appliances. The previous reports have dealt with the piston jig, coal-washing table, pneumatic table, and Baum-type jig.5/ Such studies of the separation accomplished by any form of concentration device are essential and necessarily preliminary to any intelligent attempt to improve the performance of such equipment Object and Plan The pulsator-type jig was developed recently by G. A. Vissac. Although two articles(2) describing plants using this type of cleaning unit appeared in 1936, both dealt principally with plant design and layout rather than with plant performance The object of the stork described in this report was to determine the efficiency of the separation made by the pulsator jig on a sized feed, the specific gravity at which the separation between coal and impurity was effected, and the influence of the specific-gravity composition of the coal on the character of the separation made.

Jan 1, 1938

By Jerry C. Tien

China?s remarkable levels of economic growth during the past three decades have lifted almost 300 million people out of poverty. This amazing achievement has placed an increasing demand on energy and minerals, especially coal, which supplies 68.7 percent of China?s energy (June 2011). It is estimated that China mined more than 3 Gt (3.3 billion st) of coal in 2010, three times as much when compared to merely 10 years earlier. Such an impressive achievement does not come without major costs ?? including concerns with mine safety and an increasing number of occupational illnesses due to fast growth. This article reports on one of the major safety concerns in China?s coal mining, dust and dust control practices, and known cases of caol worker?s pneumoconiosis affiliated with prolonged exposure to excessive coal dusts. The exact size of China?s mining industry is not known, but it is estimated the coal industry is at least five-million people strong, and the metal and nonmetals industry probably employs another three million people. To meet increasing energy demand, China mined more than 3.1 Gt (3.4 billion st) of coal in 2010 from its 15,000 plus coal operations1, most of which are small- to medium-sized operations with annual coal productions ranging from a few thousand tons to 300 kt (330,000 st). These small coal operations are typically in remote areas, inadequately engineered, poorly ventilated and still using rudimentary drilling and blasting mining methods employing antiquated mining equipment and, presenting safety concerns, i.e., methane and dust explosions.

Jan 1, 2011

By Charles G. Maier

"INTRODUCTION The use of thermodynamic calculations to answer practical problems in metallurgy, especially those that are relatively difficult to test experimentally, is rapidly becoming a conventional method of procedure. Nevertheless, these methods cannot he applied effectively until the fundamental thermodynamic constants used for them have become available either by direct experiment or by recalculation of data already existing in more or less undigested form.In an attempt to collect such data far the compounds of lead and the antimony group the incentive has been to make a preliminary survey that will disclose the gaps or questionable phases of available information and to collect data that may be used to answer certain rather practical problems presented by operating metallurgists.This report comprises three sections; the first gives the basis of selection of the constants which may now be given or estimated, and the later sections discuss the application of the figures obtained to two of the more interesting problems.The reader will discover that many of the quantities involve critical study of a number of more or less discordant observations. Although certain data could be rejected on the basis of thermodynamic comparisons, it must not be overlooked that many of the figures are the results of rational estimates rather than exact experiment. The use of thermodynamic methods to control and partly authenticate such estimates is one of its most valuable characteristics for the practising metallurgist or chemist, who cannot check by direct experiment each property of the materials which he converts to usable form.Nevertheless, while it is definitely possible in certain instances that the final figure selected for the heat or free energy of a process or substance may be in error by as much as a few hundred to a few thousand calories per formula weight, questionable figures are usually revealed by the thermodynamic calculations made. When quantities of such degree of accuracy are, and they often must be, used for estimating an unknown reaction, the result often gives no more than the order of magnitude of the desired quantities. Yet even in these extreme cases the answer is far more reliable and valuable than an unordered guess or a conclusion based on incorrect data."

Dec 1, 1934

By M Thierry Bernart

The software QUALITIR is a software developed by CNSIDCI, framework on five research and experimentation years. This conceived tool by specialists for professionals is a decision aided design tool concerning mining. It makes party the rare software regrouping the different themes approached by the profession namely, the general idea of blast design, blasting sequences, the fragmentation as well as the study of vibrations. Henceforth it is by the intermediary of such tools that performances in term of profitability, security or impact on the environment will be able to be realized.

Jan 1, 1997

By A Asadov, D Nair

This paper discusses the determination of the percentage of crystalline material in a natural silica deposit which would be considered harmful to health (<10 ¦m). A sample of the natural silica material was recovered and split into a number of subsamples. Samples were sieved using a conventional dry sieve to remove material >300 ¦m before testing. Particle size analyses of the fine fraction showed 75 per cent of the material was below 10 ¦m. Initially XRD and XPS were run on the samples to determine the minerals and composition of the sample. The XRD revealed strong quartz peaks and smaller tridymite peaks with a high amorphous background. The XPS indicated traces of iron, titanium and carbon with dominant silicon and oxygen peaks. The structure of the sample was investigated using the SEM. It was apparent that there were a number of larger quartz crystals (>30 ¦m) with a mix of amorphous and crystalline in the finer fraction. It was also observed that amorphous material was attached to the surface of the crystals. In order to determine the percentage of crystalline quartz a known amount of quartz was added to the sample incrementally. On each addition an XRD scan was performed and the area under the peaks recorded. Back analysis of these peaks with an assumed percentage of crystalline material in the original sample gave a crystalline content of 30 per cent. The quantity at the respirable fraction was estimated to be 18.7 per cent.

Jan 1, 2003

By S. H. Ash

THE INUNDATION of anthracite reserves in the Eastern Middle field of Pennsylvania affects the life of the anthracite industry in this field; it also influences the economic status of people, communities, and industries that depend wholly or in part upon anthracite for their livelihood. The trends of production and of employment in the anthracite-mining industry in this field are downward, and they probably will continue in this direction. The reserves have been depleted to the extent that the end of the active life of the industry as a. major economic factor is approaching. By removing the water in those pools where it can be done economically, the future of this industry may be extended somewhat.

Jan 1, 1950

By Oliver Bowles

"Underground operation.In its broader sense the term ""mining"" is applied to all processes whereby raw materials are taken from the earth to be used as sources of mineral products. In a more restricted sense ""mining"" is applied to underground operations as contrasted with open pit work designated as quarrying. The tern is used in the restricted tense in this paper; for it relates to the exploitation of limestone deposits by modern methods of underground operation rather than by open pit methods.Present tendency toward miningIt may seem to some readers that a paper on mining limestone will find little general interest among lime plant operators, for only a limited number of them have yet resorted to this means of procuring raw materials. It is noteworthy, however, that a growing tendency exists toward underground operation, for one by one quarry owners are faced with increasing difficulties in open pit operation. It seems desirable, therefore, for operators to keep closely in touch with this gradual change in process, to inquire into the underlying causes, to compare costs, and to study the effects of the change in method on subsequent steps in calcining the stone to produce lime."

Mar 1, 1924

By N. Damiano, C. Zhou, R. Jacksha, J. Srednicki

Modern electronic devices and systems used to enhance miner safety and health are becoming commonplace in underground coal mines. The ability for these devices and systems to function properly in the presence of electromagnetic emissions from other electronic and electrical devices and systems is not entirely understood. To investigate potential electromagnetic compatibility issues of critical mine electronic devices and systems, researchers from the National Institute for Occupational Safety and Health (NIOSH) are conducting surveys of electromagnetic emissions in underground coal mines. This paper presents the measurement system, methods, and results of electric field electromagnetic emission surveys conducted in three underground coal mine environments in the frequency range of 10 kHz to 1000 MHz. The survey data show that in some environments electric field electromagnetic emissions in underground coal mines approached or slightly exceeded limits as defined by other industrial sectors.

Mar 2, 2022

By L. Hoffman, F. Seymour, S. Hoerger

Newmont has a large integrated operation in Northern Nevada with numerous mines, stockpiles, and processing facilities. There are over ninety defined metallurgical ore types and over sixty defined gold recovery process options. To take better advantage of the available synergies, a complete Nevada wide mine plan and process model along with a mixed Integer and Linear Programming optimization tool has been developed and implemented. This system is maintained and operated by a Nevada Planning Group. Standard in-house planning software tools and methods have been implemented at all mine sites. While increasing the effectiveness of planning in Nevada, these changes have allowed a significant reduction in overall Mine Engineering staff.

Jan 1, 1999

By C. Özgen Karacan

Methane emissions from the active face areas and from the fractured formations overlying the mined coalbed can affect safety and productivity in longwall mines. Since ventilation alone may not be sufficient to control the methane levels on a longwall operation, gob vent boreholes (GVB), horizontal and vertical drainage boreholes, and their combinations are drilled and used as supplementary methane control measures in many mines. However, in most cases, the types of degasification wellbores chosen are decided based on previous experiences without analyzing the different factors that may affect this decision. This study describes the development of an expert classification system used as a decision tool. It was built using a multilayer perceptron (MLP) type artificial neural network (ANN) structure. The ANN was trained using different geographical locations, longwall operation parameters, and coalbed characteristics as input and was tested to classify the output into four different selections, which are actual degasification designs that US longwall mines utilize. The ANN network selected no degasification, GVB, horizontal and GVB, and horizontal, vertical and GVB options with high accuracy. The results suggest that the model can be used as a decision tool for degasification system selection using site- and mine-specific conditions. Such a model can also be used as a screening tool to decide which degasification design should be investigated in detail with more complex numerical techniques.

Jan 1, 2009

By D Kilkenny

Underground contractors in the mining industry must be prepared to take a position at the forefront of innovation of equipment and work methods in order to maintain a competitive advantage over in-house operations and remain relevant. Innovative concepts such as split-feed development jumbos, high capacity trucks and loader guidance systems were implemented by contractors to stay ahead of ‘the pack’. All of these are now common across the industry.The demands of regular participation in competitive tendering coupled with aggressive fleet depreciation, means contractors tend to have more communication and opportunities to work with equipment suppliers than mine owners. Therefore, they are more likely to influence equipment design and product directions. They also have a unique opportunity to assist in trialling new concepts and technologies across a wide variety of operating conditions rather than being restricted to one mine.In addition, as a ‘guest’ on a mine site, mining contractors do not have the luxury of creating the environment for their preferred systems, rather they must have the capacity to adapt their technology to suit the offered environment at a particular mine. This leads to a pursuit of adaptive technologies that can be implemented selectively and seamlessly without excessive disturbance rather than ‘all-of-mine’ systems. These incremental innovations then become available for use across the mining industry where they can add value as ‘bolt-on systems’ to existing operations.Mining contractors, therefore, act as the bellwether for industry practices and equipment. However, in order to maintain their position they must engage industry stakeholders to deliver practical, innovative and cost-effective technologies that add value and result in an improved bottom line for all. This paper uses case study material to illustrate how the Byrnecut Group has approached innovation and how the theory of Disruptive Technology applies to underground mining innovation.CITATION:Kilkenny, D, 2017. Innovation in mining – a contractor’s role, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 59–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

Separation of Nickel and Cobalt from Manganese, Magnesium and Calcium by Synergistic Solvent Extraction - From Batch Tests to Pilot Plant Operation The synergistic solvent extraction system consisting of Versatic 10/LIX63/TBP was used for the separation and purification of nickel and cobalt from synthetic laterite leach solution after iron removal. Very encouraging results were obtained for separating nickel and cobalt from manganese, magnesium and calcium. In batch tests, the organic composition of the synergistic system was optimised and very large synergistic shifts for nickel and cobalt were observed. The ?pH50(Mn-Co) and ?pH50(Mn-Ni) values were as large as 1.65 and 2.40, respectively. The extraction and stripping kinetics of nickel and cobalt was fast. Semi continuous extraction tests were conducted with a pH profile of 5.5/6.1/6.5 in three stages at 40¦C. The nickel and cobalt extractions reached 99.9 per cent with only 5 mg/L Ni and <1 mg/L Co left in the raffinate. With two stages of scrubbing, only 2 mg/L Mn and less than 1 mg/L Mg and Ca were left in the scrubbed organic solution. With two stripping stages, the stripping efficiencies of Ni and Co reached over 95 per cent. A fully continuous pilot plant operation was conducted successfully for 280 hours. With an O/A ratio of about 2 and a pH profile of 5.5/5.8/6.0/6.3 for the four stages EX1/EX2/Ex3/EX4, both nickel and cobalt were almost completely extracted. Using a pH profile of 5.4/5.0 for SC1/SC2, the manganese scrubbing efficiency was over 96 per cent. Using three strip stages, over 98 per cent Ni and 99 per cent Co were stripped with only 64 mg/L Ni in the stripped organic solution. The nickel concentration in the loaded strip liquor reached 83 g/L, resulting in a ?Ni of over 28 g/L. The chemical stability of the system was also assessed over 12 weeks under proposed industrial operating conditions. Operation exclusively under strip conditions at 50¦C and 40¦C resulted in LIX63 oxime half lives of 1.1 and 2.1 years, respectively. Operation exclusively under extract conditions at 50¦C and 40¦C resulted in oxime half lives of 0.26 and 0.82 years, respectively. Losses of Versatic 10 were less than four per cent.

Sep 13, 2010