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By Charles L. Kimbell

The year 1977 generally was a year of growth in overall world mineral industry activity, although there were downturns in major elements of the world's iron and steel industries. The sharp upturns in market economy nation activities that were noted in 1976, following the reduced performance levels of 1975, were moderated, and in the centrally planned economy nations, overall mineral industry activity apparently continued to increase, but at a pace in keeping with that of 1916 rather than at the higher rates of the earlier 1976's. Noteworthy during the year, if only in a negative sense, was the inability of world powers to reach any significant agreement on issues relating to deep seabed mining. Interest from a commercial viewpoint centered around deposits or so-called manganese nodules. These materials, which indeed are chiefly manganese in terms of their content on a quantitative basis, really were of commercial interest primarily far their copper, nickel, and cobalt content. Participants at the Third United Nations Law of the Sea Conference looked into seabed mining rights, but reached no mutually agreeable decisions.

Jan 1, 1981

By K. Huessener

This paper attempts a survey of the principles involved in the combustion of blast-furnace gas in boilers and stoves. I do not expect to be able to give much information which is actually new, since the laws and methods of calculation pertaining to this problem are contained in a number of handbooks; but, so far as I am aware, they have nowhere been treated exclusively with reference to this one problem of gas economy. The road which I follow is less that of strictly scientific research than that of the practical engineer, faced by operation problems which require a quick solution by easily accessible means without a prolonged search in scientific handbooks. For this purpose I give a number of tables and diagrams, as well as the results of many years1 practical working experience as combustion engineer, which I trust will prove useful to my readers. HlSTORICAL Considering the tremendous efforts made during the last 15 years to increase the efficiency of all kinds of power plants, it is highly surprising that until a comparatively very recent period, progress in the economical combustion of blast-furnace gas has been so slow, The explanation generally put forth, that fuel has been so cheap that it was hardly worth while to bother about this economy, will not hold good, for the greatest trouble was taken to improve the combustion of coal and to reduce the consumption of steam, The most plausible explanation appears to be the general impression, held as an accepted fact, that gas, especially hot, uncleaned, blast-furnace gas, was not a good boiler fuel. Many managers of high repute had tried unsuccessfully to improve the conditions of its use, and the dictum went forth that efficiencies of over 60 per cent., particularly with high loads, were impossible. This was the situation not only in the United States, with very cheap fuel, but also in Europe, where fuel prices are twice and three times as high.

Jan 1, 1916

By A. V. Reddy, C. Beckermann

"The DC continuous casting of a grain refined AI-4.5%Cu round ingot with realistic boundary conditions is numerically simulated. Of particular interest are the effects of the transport of free solid in the form of equiaxed grains on the macro segregation patterns and the final grain size distribution. The study uses a previously developed two-phase model that incorporates descriptions of heat transfer, solute redistribution, melt convection, and solid transport on the system scale with microscopic models of solutal undercooling, microsegregation and grain impingement. The numerical results indicate that grain transport inhibits the formation of inverse segregation in the ingot shell and promotes negative centerline segregation. This is explained by the reduction in the solid coherency next to the mold and the advection of solute-lean grains towards the centerline. Comparisons with the experiments of Finn et al. [5] illustrate the need for considerable improvements in the model. IntroductionMacrosegregation continues to be one of the concerns in DC continuous casting of aluminum ingots. The variation in composition over the ingot cross section results in the need to adjust alloy composition in order to meet mechanical property specifications in finished products. The extent of macrosegregation is greatly affected by the casting conditions, such as casting speed, superheat, cooling rate, mold size, alloy composition, and grain refining practices. Thus, it is of great interest to develop a comprehensive mathematical model to simulate the casting process, enabling the selection of conditions that minimize macrosegregation while maintaining a high productivity."

Jan 1, 1994

By L. R. Burdick, J. F. Barkley

"There is a general conceit in the coal trade that the moisture- and ash-free B.t.u. of coal from the same seam, and surely from the same mine,is substantially a constant; that calculation of the moisture- and ash-free B.t.u. value from the proximate analysis and B.t.u. determined in the laboratory will reveal whether a coal came from a given area or seam; and that, having this constant, the B.t.u. value of a coal sample can be calculated fairly closely upon a dry or as-received basis from the moisture and ash values of its proximate analysis.To illustrate with a simple example;"

Jun 1, 1941

By WenFeng Li

Comparing to the coal seams in Eastern China, the coal seams in Western China usually have better geological conditions. Therefore, changes in the conventional gateroads layout are required for the Western longwalls. A case study based on a Western coal mine (LiMin) was presented to discuss the feasibility of an innovative gateroads layout. Based on the geological conditions, a 5m wide pillar between the adjacent two longwall panels, 09112 and 09113, was proposed in order to increase the recovery rate. More importantly, the entry supporting strategy of panel 09113 headgate needed to be determined and verified carefully since only 5m wide pillar was left to separate the entry from the panel 09112 gob. Three strategies with different supporting intensities in the panel 09113 headgate were evaluated by numerical modeling. The model outputs indicated that roof and rib boltings plus single hydraulic props were essential to maintain the gateroads stable. Field observation showed that under the proposed entry supporting strategy, the total roof-tofloor and rib-to-rib convergences were only 360mm and 460mm, respectively, during the service life of the panel 09113 headgate, which indicated that the innovative gateroad layout proposed in this paper is suitable for longwalls with similar geological conditions in Western China.

Jan 1, 2013

By Charles L. Kimbell

For the world mineral industry as a whole, the year 1981 was a period of continuation and, in some instances, an acceleration of negative trends extending back into 1980. Most available statistical data reflected stagnation or downturns in activity. Levels of production, trade, and consumption declined for a substantial number of leading mineral commodities, including, most notably, steel and petroleum. Investment, if not lower than in 1980, was evidently increasing at a more modest rate. Prices for major mineral commodities were generally lower, at least in terms of constant dollars, and in some cases even in terms of current dollars. Prospects of a major reversal of these patterns seemed dim. The mineral industry, however, was far from alone in this general downturn; most other elements of the national economies of the world's nations fared little better. General conditions of inflation, recession, and reduced industrial product consumption were reflected in most other sectors of the total economy. International political events continued to influence mineral output and flow but had less influence on overall levels of activities than on the geographic distribution of these activities. The Iran-Iraq war certainly played a role in reducing mineral industry activities in those nations, but the commodity most affected, petroleum, was available from other sources in sufficient quantity that, in the face of reduced demand, a substantial surplus developed.

Jan 1, 1983

By MARK J. VANARELLI

Estimating groundwater inflows in rock deep tunnels is critical to the safety of personnel constructing the tunnel and the cost of construction. This paper presents two case studies for estimating steady-state groundwater inflows into deep rock tunnels. The case studies included the Chattahoochee and Nancy Creek tunnels. In this paper, statistical methods were applied to packer test data obtained from exploratory borings during geotechnical site investigations. A semi-empirical procedure was utilized for estimating groundwater inflows into these deep rock tunnels. It is the most widely used method/procedure in the tunnel industry. The Chattahoochee and Nancy Creek tunnels are deep rock tunnels which exhibit radial flow conditions. For the radial flow condition, a statistical analysis presented in this paper indicates that the semi-empirical procedure works well; however, variations in the procedure and/or an insufficient amount of testing could lead to underestimations of the inflow quantities. Packer test data plotted in histograms were observed in all cases to be log-normally distributed for the radial flow condition. Modeling using Monte Carlo simulations was observed to be an effective tool for removing irregularities in the distribution of the data and incorporating high-end permeability data to derive reasonable groundwater inflow estimates. This paper is based on the PhD thesis entitled “Improvements to the Current State of the Practice in Steady-State, Groundwater Inflow Estimates into Rock Tunnels based on the Application of Statistical Analysis Methods of Packer Test Data obtained from Exploratory Borings During Geotechnical Site Investigations.”

Oct 9, 2020

Jan 1, 1955

By G. Stenning

The paper outlines the need for high-volume ventilation in a uranium mining operation based on the design to meet environmental requirements for dust, radiation and diesel equipment. Mining methods in a highly mechanized operation, a key factor in design, are discussed. The construction and installation of major intake and exhaust fans are described briefly, together with the development of the mine airways and distribution system. Controls in the form of doors and bulkheads are important considerations in planning. Finally, the need to lower ventilation requirements in response to increasing power costs will result in future improvements.

Jan 1, 1979

I attended a funeral in West Monroe, Louisiana, for one of the best powder peddlers I’ve ever known. He started work in 1948 for Dixie Dynamite, a seismograph explosive distributor. His first job was as a truck driver, then magazine keeper and then sales re p re s e n t a t i v e . When Dixie Dynamite quit, he acted as an explosives sales agent for sometime before moving on to Kansas to be a sales rep for a distributor there. We called him the “ragin cajun” long before James Carville came on the national scene messing up things. While he was born in G e o rgia, he was a Cajun at heart. I don’t believe the old saying, “Build a better mousetrap and the world will beat a path to your door.” To me, the best products in the world need to be sold. Two examples of this are the Beta system for TV and the Apple Macintosh computers. Beta is the best system but VHS took over because the Beta people fell down on the selling job. Windows 98 is Macintosh ‘86 but again the engineers were not salesmen. Marion “Johnny” Johnson who was buried only about a half mile from his first magazine site proved that good selling is good citizenship. He could have sold any firstclass product, for he wouldn’t tolerate inferior items, and made a successful career of it, but he chose dynamite and the industry benefited from his talents.

Jan 1, 2004

By I. C. Brown

Introduction Many tables of nomenclature for igneous rocks have been introduced from time to time, and each has its strong proponents. As a result, any discussion of igneous? rocks is apt to prove confusing unless the names used for these rocks are defined. This ?became so obvious to a discussion group, formed by the members of the Geological Survey of Canada in 1948, that an attempt was made to establish a scheme of nomenclature that could be used by any member mapping anywhere in Canada. The writer was asked to co-ordinate the ideas presented by individuals in the discussion group, to arrange them in tabular form, and, later, to distribute copies of the resultant table to Canadian universities, provincial geological surveys, and some other geological discussion groups. Many useful suggestions and criticisms were received, were studied ?by members? of the original group, and, so far as practicable, were incorporated in the scheme of nomenclature. The result is the table presented here. This nomenclature of igneous rocks is at present being used by most members of the Geological Survey of Canada who are working with igneous rocks, and by some Canadian universities. We hope it will be found useful and be more widely accepted. With this idea in mind, certain principles were adopted in drawing up the nomenclature.

Jan 1, 1952

By D. Donald Downey

Pilot Testing Ion Exchange Resin (IEX) can go from very simple beaker testing to complicated column testing. Space velocities, regenerant quantities, loading capacities, ion leakage, are all terms that get accumulated together to prove or disprove a resin’s (or resins’) ability to load a single ion (or specific set of ions). Not getting all the resin’s operating parameters correct will disqualify (or at least skew) the results. Laboratory tests for capacity, moisture content, bead size, metals fouling, etc.—what does it all mean? At last count, there were over twenty-five separate ion exchange resin tests (analyses) that were available to end users. Standard testing procedures identify the resin properties but more specific procedures can be used to identify problems with equipment operation. Then, there are the costs to consider; simple cation resin testing (moisture content, total capacity and bead integrity) is in the $200/sample range. However, add to this Chatillon, Russian Ball Mill Test, HIAC particle size, metals and % regeneration test procedures and the lab work can increase to over $1000/sample. In this paper, the author will explain the “must-do” pilot and test procedures and why they are important and the key to understanding how resin performs ion exchange.

By E. J. Berentsen

The Turquoise Ridge gold deposit is located near the Getchell Mine, 72 km (42 miles)northeast of Winnemucca, NV (Fig. 1). The deposit is owned by Getchell Gold Corp. The host rocks consist of Ordovician and Cambrian age shales and limestones. They have been crosscut by the northeast-trending Turquoise Ridge shear zone and northwest-trending shear zones. Gold mineralization occurs at depths from 427 to 671 m (1,400to 2,200 ft) along the intersection of these structures. Large tonnage, flat-lying deposits occur where folded, favorable beds are intersected by the faults. The carbonate in the beds has been replaced with silica, pyrite and arsenic sulfides.

Jan 1, 1996

Overview n Why we audited the IRS n How we did it n What we discovered n What we learned n Where we are going next The unbroken chain of safety The Internal Responsibility System (IRS) The network of roles and relationships in a workplace, through which everyone works with mutual commitment to reduce or eliminate hazards.

May 1, 2003

By M. Javier

"Mining makes civilization possible. It also creates socio-economic problems surrounded by sustainability controversies yet continues extraction without considering the balance and finitude of nature. Nature requires restoration of equilibrium if mining and life on earth are to continue. Mining is still practiced according to Agricola’s views and the consequences it has wrought on our planet demand we critically reexamine it from its very core, to its metrics, to its design, to its technology, to how it is taught, and to reconsider its raison d'être in 2017. This paper offers tools to new mining engineers that are required to transform and solve new challenges. The task before us is to formulate an updated core curriculum that meets the demands and realities of the 21st Century. Mining professionals must rethink and reteach how to redesign mines before shovel hits dirt, how to mine with restoration of nature figured in to the mining design. Mining needs a new extractive technology in order to transform the results of its well-known liabilities. Mining has evolved and its future must be different than its past. Our industry is capable of doing this but it needs to be shown the way. INTRODUCTION The statement that ‘mining makes civilization possible’ is of the utmost importance and has the most value to us. We can examine the past and present appropriately to see the future that we are building. Mining must be addressed in a different way that makes a positive difference and improves upon rather than continues to get the negative impacts of the past. See Fig 1. Mining creates disequilibrium in Nature by producing ore, waste, tailing, dilution of resources, toxic, and pollution to its ecosystems. What is next for mining on a limited planet? Delaying the transformation of mining is not an option to developing an updated and modern mining business-as-usual paradigm. It is hurting the essentials of living in a civilization; our livelihood is in danger to the point of unrest in nature as we generate a lot of eco-print by present mining practices. So, we are urged to eliminate this bottleneck in life by employing a different design. This way, we will have a vision on how to sustain our civilization. [1]. This new design, with input from current and future generations, will be our contribution to posterity."

Jan 1, 2018

Isometric strength is defined as the capacity to produce force or torque with a voluntary isometric (muscle[s] maintain[s] a constant length) contraction. The key thing to understand about this type of contraction and strength measurement is that no body movement occurs during the measurement period. The tested person's body angles and posture remain the same throughout the test. Isometric strength has historically been the type most studied and measured. It is probably the easiest to measure and to understand. Some strength researchers feel that isometric strength data may be difficult to apply to some "real life" situations because in most real circumstances people are moving - they are not static. Other researchers counter that it is equally difficult to determine the speed of movement of a person or group of persons doing a job (each moves in his or her unique manner and speed across the links and joints of the body). Thus, dynamic strength test data collected on persons moving at a different speed and/or in a different posture from the "real world" condition will be just as hard to apply. In truth, neither is better - they are different measurements. Both researchers and users should collect and use data that they understand and that fits their application. Workplace Assessment When a worker is called on to perform a physically demanding lifting task, the external load produces moments - tendencies to produce motion, also called torques - about various joints of the body.(1) Often these moments are augmented by the force of gravity acting on the mass of various body segments. For example, in a biceps curl exercise, the moment produced by the forearm flexors must counteract the moment of the weight held in the hands as well as the moment caused by gravity acting on the forearm's center of mass. To perform the task successfully, the muscles responsible for moving the joint must develop a greater moment than the combined moments of the external load and body segment. It should be clear that, at each joint of the body, there is a limit to the strength that the muscle can produce to move ever-increasing external loads. This concept forms the basis of isometric muscle strength prediction modeling.(1) The following procedures are generally used with this biomechanical analysis technique. First, workers are observed (and usually photographed or video-taped) as they perform physically demanding tasks. For each task the posture of the torso and the extremities are documented at the time of peak exertion. The postures are then re-created using a computerized software package, which calculates the load moments produced at various joints of the body as the task is performed. The values obtained during this analysis are then compared to population norms for isometric strength obtained from a population of industrial workers. In this manner, the model estimates the proportion of the population

Jan 1, 1998

The energy supply in the 21st century is still secured by coal. According to estimates of the International Energy Agency (IEA), coal will have the same importance as oil for the world-wide supply of energy until 2030. Coal is also an important element of EU policy, its future use is closely linked to effectively addressing the environmental challenges it poses. Hard and brown coal represent approximately 80 per cent of European Union (EU) reserves of fossil fuels and coal utilisation can co-exist with the development of power generation based on renewables. Europe is the world's third largest consumer of coal behind China and the United States.The Czech Republic is poor in energy resources except for coal. Brown coal is relatively abundant (mineable reserves estimated at 1800 Mt, output 48 Mt/a) and significant quantities of hard coal (mineable reserves 900 Mt, 13 Mt/a), much of it suitable for coke production, are also present.Severoceske Doly (SD Company), the biggest Czech coal mining company (22 Mt/a, 48.6 per cent Czech market share) and one of the biggest in Europe, reinforces despite the last deep crisis in the Czech and European economies its long-standing stable and strong market and financial position. From 2009, the SD Company co-owns, with partners, a brown-coal mining company MIBRAG (21 Mt/a). SD Company invests in large mining equipment (eg new giant spreaders and bucket-wheel excavators, extension of overland belt conveyors), rebuilds and upgrades mining and processing installations, auxiliary and other machinery. We should see the investment we make today in tomorrow's mining and reclamation as an opportunity and not as a burden. They enable to make our position more resistant in the longer term. Projects focused on the environment and operational safety went hand in hand with these efforts.R&D activities relate to technical innovations, improvements of mining equipment, research and evaluation of conditions for extracting coal seam and/or overburden and mitigation of environmental impacts, utilisation of coal in new products. The company spends considerable amounts on reclaiming affected land and creating a new post-mining landscape.Our dialogue with influential stakeholders in the region where we operate contributes to the long-term improvement in the quality of life of local residents. Such dialogue with communities in the last ten years has been instrumental for confidence building. SD Company helps to develop many projects of towns and villages in its vicinity. The stable and transparent relations with our neighbours are in accordance with our basic principles of corporate social responsibility.

Dec 6, 2010

By Frank E. Chase

The Harris No. 1 Mine, located in Boone County, WV, has been longwalling the Eagle Coalbed for over 30 years. Harris has experienced numerous interactions associated with the extensive room-and-pillar and longwall mining operations which have been conducted in the overlying No. 2 Gas Coalbed. The problems have included roof falls, excessive rib sloughage, and gateroad and bleeder entry closure. A detailed evaluation of the multiple seam experiences at Harris No. 1 Mine was conducted as part of the National Institute for Occupational Safety and Health (NIOSH) nation-wide multiple seam mining case history data base. One observation from the Harris gateroad case histories was that smaller, critically loaded, upper seam pillars seemed to cause more severe ground conditions than did wider pillars. The LaModel program was used to investigate this supposition, and the results confirmed that "critical" sized pillars do transmit the highest amounts of stress to adjacent seams. In addition, the data suggest that the probability of a major multiple seam mining interaction increases when the depth of cover is 1,000 ft or greater and when the Eagle seam pillars have a Analysis of Longwall Pillar stability factor less than 1.50.

Jan 1, 2005

By M. Hermanus

1. INTRODUCTION It gives me great pleasure to extend my warmest greetings to everyone attending the 30th International Conference of Safety in Mines Research Institutes. I would also like to bid a special welcome to all of the international delegates who have travelled to Johannesburg to take part in what surely be a most rewarding session of deliberations. As you come together over next four days, you will have a wonderful opportunity to exchange ideas and information on strategies and practices for the implementation of sustainable patterns of development. The objectives of this meeting are both timely and far-reaching, as countries around the globe work towards the sustainable use of the world resources. Each of you brings a high level of expertise to these deliberations. I know that you will make the most of this opportunity to address the challenges and opportunities to highlight the most innovative and technologically efficient methods of social protection in order to ensure an increase in the quality of life, health, safety and living environment for the peoples of the Africa. Our country, although endowed with an immense and diverse array of mineral deposits, is perhaps best known in the mining industry for the fact that it is the world’s biggest producer of gold. Although South African gold production has declined over the past years and the industry faces serious problems, it is a myth that the South African industry is moribund. There is a new energy coursing through the South African producers which will ensure their powerful presence for many years to come, based not only on their domestic production but also and probably increasingly on their external operations. Africa features prominently in the latter category.

Jan 1, 2003

By James Dickson

Brief History of Discovery and Early Development In the first half of the nineteenth century, the only authority on the Pacific coast between the Columbia river and Alaska was exercised by the Hudson's Bay Company, who had established a series of forts and trading stations on the coast from the Columbia north to Millbank sound. The Hudson's Bay Company were chiefly interested in the fur industry, and the large influx of settlers from the eastern United States into the territory now known as the States of Oregon and Washington, about 1840, not only interfered with the fur business but involved the question whether the territory should be under the British or the American flag. Anticipating the possibility, later realized, of losing control of this area, the Company, in 1845, established their main fort and trading centre on the southern end of Vancouver island under the name of Fort Camosun; shortly afterwards changing the name to Fort Victoria. Realizing that their former policy of discouraging all attempts to develop any other business than the fur industry had lost them several hundred thousand square miles, the Hudson's Bay Company now set about encouraging settlers in the vicinity of Fort Victoria by disposing of lands to suitable parties and also to those in the employ of the Company. The usual pioneering stage was passed through with the starting of small sawmills, grain mills, etc., and the incidental work accompanying such efforts. Any coal required for blacksmithing or other purposes was brought from England around Cape Horn by the few ships that visited the Pacific Coast. About 1849, an Indian who was having his gun repaired by a blacksmith in Fort Victoria asked about the "black stones" used in the fire and, on being told that the "black stones" had to be brought a great distance, he informed the blacksmith that there was plenty of the same stone where his people lived. This information was immediately given to an official of the Hudson's Bay Company who talked with the Indian and told him that if he would bring some of the "black stones" he would get his gun repaired free and a present of a bottle of rum. Nothing more was heard of this coal until April of the following year, when the Indian came into Fort Victoria with his canoe loaded with coal, which was tested and found to be of good quality. It is reported that the Indian got his bottle of rum.

Jan 1, 1935