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By T. Lamb

There are many honor stories about aluminum in the marine environment and many are not based on facts, so they are myths. Myths must be addressed before progress can be made. This paper attempts to dispel the myths and state the facts. A common perception is that aluminum ships cost significantly more than steel ships. This paper illustrates that even though the cost of the aluminum structure is over 50% more than the steel structure, an "equivalent" aluminum naval ship can be built within 7% of the acquisition price of a steel ship. This is possible because of the cascading benefits of the aluminum ship's significantly lighter weight. Aluminum ships also have a life-cycle cost advantage over steel ships because of reduced maintenance and fuel cost savings.

Jan 1, 2011

By R. C. Dunne

As ore grades of existing and new ore deposits continue to decrease there is ever increasing pressure to decrease operating costs to maintain profitabitabitiy at existing mine sites and for new projects. The accepted solution to this dilemma in most cases is to increase treatment rate, leading to a coarser grind, at the expense of marginal decreases in recovery. The recovery loss is usually associated with losses of liberated and composite coarse material. This paper will review the practice of coarse particle flotation, including the reagent chemistry, cell hydrodynamics, froth stability, entrainment and flotation cell design, all parameters important to the recovery of coarse liberated and composite particles. This will provide a better understanding of opportunities to improve the recovery of coarse particles. Some examples will be provided.

Sep 1, 2012

By R. S. Krarner

Fly ash, a by-product of coal burning power plants, poses a major problem for the utility industry since most fly ash must be landfilled. These quantities may represent as much as 20% of the total material going into landfills. A major problem with fly ash utilization is that although the ash consists of useable components, ash composition can vary depending on the types of coal burned and plant operating conditions. Ash is first characterized using SEM, image analysis, and chemical methods. Processing techniques were developed to separate ash into various components including cenospheres, magnetic spheres, carbon, and clean ash. These products are again evaluated for various utilizations before being used to produce valuable products such as mullite, activated carbon, fillers in plastics, and concrete.

Jan 1, 1994

By Kevin Hegerle

The Henderson Mill has operated over a wide range of production rates, feed grades, manpower levels and recovery targets since start-up in 1976. Henderson Mill personnel, both management and hourly, have successfully responded to these changes by not only maintaining unit costs, but by actually decreasing unit costs. Methods of cost reduction have included conventional austerity programs, innovative technological improvements and creative work schedules. This paper addresses both maintenance and operating cost reductions and efficiency improvements.

Jan 1, 1986

By Samuel Frimpong

The preparation of graduate talent for the mining industry is a challenging process, given the multifaceted and complex array of decisions mining engineers make in discharging their responsibilities. As leaders, mining engineers must manage operations, lead project teams, mentor junior engineers, chart the technological directions of companies and deal with several organizations for maintaining the technical and economic feasibility of operations within strategic and tactical framework. Traditionally, the completion of the bachelor of science degree curriculum, with a minimum cumulative grade point average (CGPA), has been used as a graduation measure by Missouri University of Science and Technology (Missouri S&T). Companies have long realized the limitations of the CGPA for recruiting graduates because mining engineering is an applied engineering discipline. Company recruiters have sought to correct the limitations by factoring experience and behaviors into the selection process when recruiting knowledgeable and well-rounded graduates. In this paper, the authors introduce a new metric, which combines the current CGPA (knowledge) with experience and attribute (KEA) metrics to gauge the job readiness of graduating engineers. The KEA metric, also called the job-readiness factor (JRF), is the sum of K (50%), E (30%) and A (20%). The KEA process has been applied to a graduating class in Missouri S&T to demonstrate the value of the new metric system. The results show a fairly positive correlation between CGPA and the KEA metric, with a coefficient of determination of about 70%. Overall, the KEA metric system provides a better picture of the capacity and job readiness of graduates entering the workforce.

Jun 1, 2013

By B C. Povey, K Lagutin, M Mryasov, V Noll

The current Stoilensky magnetite concentrator comprises a three-stage crushing circuit followed by three stages of ball milling, grinding and concentration to produce a magnetite concentrate with 66.5% iron (Fe). The plant is built in four lines, three lines having four mills and one line with five mills, to treat 32 Mt/y of ore and produce 13.9 Mt/y of concentrate.NLMK, the owner, is Russia’s third largest steel maker and while the ore from the Stoilensky Mining and Beneficiation Plant (SGOK) provides the bulk of their supply, they still must buy ore from external sources at world prices. A decision was taken to expand the SGOK operation to supply all the NLMK concentrate, including the production of pellets.To commence the expansion, high pressure grinding rolls (HPGRs) were introduced as a fourth stage of crushing ahead of the first ball mill. This was a relatively low capital cost expansion and increased production by 12 to 15%, the cost being much less than an additional grinding line. The importance of this development was that earlier introductions of HPGRs in Russia had presented several problems so there was some reluctance to the initial concept. The even greater significance was that nearly every magnetite plant in Russia had a three-stage crushing circuit so the successful introduction of HPGRs was of interest to many operators.The design was developed by a team, consisting of Worley Parson, Mineralconsult and PiterGORproject (PGP), for the first four units to fit inside existing building structures. The first two units were commissioned in March 2016 and the next two units in May 2016, and production improved by over 12%. The design of the installation of the final four units is in progress and the installation is expected in late 2017.CITATION:Povey, B C, Noll, V, Lagutin, K and Mryasov, M, 2017. Introducing HPGR quaternary crushers in a Russian magnetite operation – challenges and solutions, in Proceedings MetPlant 2017, pp 84–100 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By Rena I. Geroyan

This U.S. Bureau of Mines report presents an evaluation of the coal mining industry's impact on the economy of Pike County, KY. A software package called IMPLAN was used to perform the analysis. The results of this study show that coal mining was the primary income producing industry in Pike County in 1990, accounting for about 46% of the county's Total Industry Output, and 21% of the total employment.. Coal production in that year amounted to 29.6 M mt (32.6 M st). Two alternate economic scenarios were developed to study the potential effects of changing coal market conditions on the county. Scenario A assumes market changes result in a coal production increase of 4.5 M mt/yr (5.0 M st/yr), and scenario B assumes a decrease of 4.5 M mt/yr (5.0 M st/yr). Scenario A would result in a 15.3% rise in the value of Pike County's Total Industry Output, adding a total of 1,663 jobs (+6.1%) in all sectors in the county. Scenario B would have the opposite effect, decreasing the Total Industry Output and employment by identical amounts. Such knowledge would allow local and regional officials to anticipate the economic and social impacts of shifts in coal production, and plan accordingly to mitigate impending changes.

Jan 1, 1994

By Árpád B. Palotás, Adel F. Sarofim, John B. Vander Sande, Lenore Rainey Christian, J. Feldermann

"Interest in the fine structure of soots and carbon blacks is motivated by a variety of possible applications. The structure provides information on the origins of the particles and on their adsorptive and reactive properties. This paper describes a method for quantification of the structure of soots and carbon blacks based on direct electron microscopic observation followed by image analysis of these materials. High-resolution transmission electron microscopy (HRTEM) provides a very detailed observation of particle structure. The differences in soot structure, because of its complexity, may not be easily quantifiable with the human eye; therefore, high-level computer software has been used to manipulate HRTEM images. This technique involves the application of fast Fourier transforms (FFT) to single particles and the measurement of characteristic parameters such as interplanar spacings and crystallite sizes from these particles. The methodology and application of this characterization technique are presented here. Results are shown for dif¬ferent samples obtained from soot and carbon black particles selected to illustrate the capabilities of the methodology. Quantitative information can be obtained on structural characteristics, e.g., interplanar spacing, circularity, orientation, elongation, and length distribution of lattice fringes, as well as on the fractional coverage of the extracted pattern. c 1996 Wiley-Liss, Inc.This paper presents a combination of techniques for recognizing and classifying different carbonaceous materials, using their structural morphology. A new method to assess and quantify the parameters which define such structures is proposed and discussed. The technique is based on the use of HRTEM (high-resolution transmission electron microscopy) and computational image analysis.It is well-known that carbonaceous materials like graphite, soots, coals, cokes, chars, etc. possess characteristic structural appearances which can vary from mostly random or amorphous to a perfectly ordered graphitic crystalline structure (Buseck and Bo-Jun, 1985; Buseck et al., 1987). The carbon structure has been variously described as turbostratic (Oberlin, 1989) or as crumpled sheets (Rouzaud et al., 1991) to indicate that parallel layering, reminiscent of graphite, is observed over dimensions of nanometers, but that these planes or crystallites show disorder over larger scales. The degree of order of such structures is strongly dependent on the thermal treatment of the material as well as on the composition of the source of the carbonaceous material. The value of the electron microscope in studying the morphology of such materials has been well-established, and abundant information is available (Ishiguro et al., 1991; Lahaye and Prado, 1978; Buseck, 1992).The use of HRTEM has brought further insight into this matter. Qualitative assessment of the structural order of such materials has been attempted over a long period of time in order to differentiate between various sources or treatments. There is, to date, no successful method available for quantifying the structural characteristics of various carbonaceous materials. This paper presents a technique which is able to recognize dif-ferent materials and to quantify the structural parameters of those materials using HRTEM and computational image analysis, including pattern recognition techniques.In the case of perfectly ordered graphitic crystals, electron diffraction is widely used for obtaining details on structure. Analysis of diffraction patterns can reveal parameters such as interplanar spacing, d002, crystallite size along the c-axis, Lc, crystal size in the plane of the layers, L., mean number of crystallites, Nc, etc.Complicated electron microscopy methods such as defocusing, tilted illumination, axial illumination, etc., often have to be used in order to characterize complex materials such as randomly oriented crystals in soots and carbons. Obtaining the right fo"

Jan 1, 1998

By David R. Cole

Before discussing some of the specific public relations issues in Colorado mining, I would like to define public relations, identify the "publics," review Colorado's population profile, and outline Colorado's mining history. Public Relations In describing public relations, a definition which is frequently quoted appeared in the PUBLIC RELATIONS NEWS, and is as follows: "The Management function which evaluates public attitudes, identifies the policies and procedures of an individual or organization with the public interest, and executes a program of action to earn public understanding and acceptance..' As you can see, this covers a "multitude of sins."

Jan 1, 1975

By C. W. K

This little sketch of the late Willet G. Miller, Provincial Geologist of Ontario, is intended to be neither a biography of his career nor a eulogy of his life. His biography has already been written in an incomparable manner by Mr. T. A. Rickard, his eulogy by Canon Cody. What more can be said of Dr. Miller than is summed up in the words of that great Canadian divine, Canon Cody, that he was "Big in body, big in heart, and, as we learned, big in brain." This article, then, will merely record a few personal reminiscences of the man himself, and while they are necessarily disjointed, they may at least serve to illustrate certain traits in his character which are not generally known or appreciated outside of the circle of his intimate friends. In the latter part of May in the year 1904, Willet G. Miller, with two? assistants, set out for the small village of Haileybury to begin his geological work in the area a few miles to the south which he was soon to name Cobalt. At that time the Timiskaming and Northern Ontario railway was not finished, although the right-of-way was cleared and partly graded. The nearest railway station was on the Canadian Pacific at the south end of lake Timiskaming, from which point the old steamer Meteor carried passengers and freight up the long, narrow and deep waters of lake Timiskaming, a very pleasant trip of some sixty miles. On this particular trip there was a fairly large crowd on board consisting of settlers going into the clay belt north of lake Timiskaming, of lumbermen, and of a few merchants and commercial travellers who were interested in the small business centres of Haileybury, New Liskeard and Ville Marie. Scarcely any attention was paid to the reports of the newly found silver deposits, although the daily papers had announced discoveries in the district six months before. As a matter of fact, the chief excitement on board was afforded by a moose, which, in swimming from the Ontario to the Quebec shore of the lake, crossed the bow of the boat, the captain steering to within a few yards of the terrified animal.

Jan 1, 1925

By G. A. Van Wielingen

"The conditioning of natural gas to meet contract pipeline specifications involves in the majority of cases in Western Canada, the appropriation of substantial capital expenditures for treating and processing installations. It is therefore of vital importance to the owners and producers of natural gas to arrive at an appreciation of the economics pertaining to the production and surface handling of their gas reserves at the earliest possible stage of field development. The treating and processing of natural gas often results in considerable changes in composition and related physical characteristics between the wellhead and the point of delivery of the saleable gas. This paper presents a general outline of engineering calculations which can be applied in the pre-determination of the effects that surface handling of gas will have on the composition and physical characteristics of sale-able gas. Emphasis has been placed on the calculation of hydrocarbon dew-points, heating values and shrinkages prevailing at the various stages in the surface handling of natural gas. It is believed that advance information indicating the approximate ranges of these physical properties will facilitate process selection and will provide a basis for the estimation of capital and operating costs of process installations."

Jan 1, 1960

By Rajesh K. Mishra

The person in charge of Environmental Affairs in a small business has many higher priority projects (such as making money to meet the employee? payroll etc.) than filling out and filing the regulatory forms. It is but. natural to think that these affairs can be managed? by playing ignorant until audited by the regulatory -state and federal agencies. Truth is to. the contrary; generally, it is too late by then. The fines and legal costs even for failing to file the regulatory forms could deliver a serious blow to the financial well-being of a small business. Forms and reports under SARA Title III are not hard to complete., but they are time consuming. In this paper we will discuss the information and data compilation procedures, simplification of some legal terminology into simple technical language, and tips that help in filling out the forms?. Some actual case 'histories of EPA fines will also be reviewed.

Jan 1, 1992

By M D. Sussman

A large number of countries in the world now have some regulation for labelling the presence of genetically modified organisms (GMO) in food. For the last ten years, ISO/TC 34/SC 16 has been providing methods, guidelines and requirements concerning the evaluation of molecular biomarkers including GMOs. This activity makes sure that stakeholders on all sides of commercial transactions are satisfied and their marketing or regulatory needs are met. Developing and maintaining a transparent, science-based environment for users of horizontal methods for molecular biomarker analysis is a high priority. Sampling and analysis of molecular biomarkers has become critically important for food and agricultural organisations developing, producing, distributing and selling genetically engineered, non-genetically engineered, identity preserved and/or organic crops and their derived products and preventing their respective destructive diseases. To aid in international harmonisation, a new work item proposal to develop an ISO type A management system standard (MSS) for organisations including laboratories using molecular biomarker analysis and sampling has been submitted to ISO/TC 34/SC 16. The purpose of this MSS is ensuring that determination of the presence, absence or quantification of a particular biomarker with a relationship to a product quality determinant, a marketing claim, a regulation or a plant pathogen is carried out under a suitable quality assurance / quality control system. This MSS will provide an overarching system to apply and manage molecular biomarker analysis and sampling for any organisation large, medium or small in a private, government or academic setting.CITATION:Sussman, M D, 2017. ISO/TC 34/SC 16 horizontal methods for molecular biomarker analysis – molecular biomarker analysis and sampling management system, in Proceedings Eighth World Conference on Sampling and Blending , pp 295–302 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By D. Harrington

"While distribution of air currents to working faces is a necessity in coal mines, especially those having explosive gas, advancing faces in metal mines rarely have circulating air other than the ordinarily inadequate amount supplied through the compressed air system. Even where comparatively large quantities of air pass through main mine shafts and levels. whether the circulation is actuated by fans or by natural ventilation, only occasionally can a metal mine be found where any considerable percentage of the ""blind ends"" has circulating air of sufficient velocity to be measured by an anemometer or even be discerned by deflection of flame of candle, or of acetylene lamp; and unfortunately these ""blind ends"" include nearly all of the places from which rock is taken.During several years study of metal-mine ventilation in various mining districts of the United States, it has been found that in some mines many of the workers in ""blind ends"" practically continually breathe air with 0.02 to 0.04 per cent of CO gas from unremoved fumes from explosives; in other mines CO2 chiefly from timber decay and breathing of men, is so high that a candle will not burn though usually the acetylene lamp will, hence oxygen is below 17 per cent but above 12 per cent; in some regions CO2 from strata fills the entire mine forcing cessation of work; in other mines in dead ends, gases such as nitrogen, H2S, SO2, etc., are found under some conditions. In many regions with hot rock or water (especially in deep workings) men in blind ends must work with little or no circulation, in air above SO degrees F. and even above 90 degrees, relative humidity only too frequently being around 100 per cent; in other regions workers in blind ends in practically ""dead"" air must continually breathe enormous quantities of finely divided rock dusts. All of the above conditions are decidedly harmful to health and prevent the worker from delivering anything approaching an adequate quantity of work, and in addition, some of these conditions have direct or indirect effect in bringing about definite increase of accidents; all of the above mentioned bad conditions in ""blind ends"" in metal mines as well as their ill effects, are remediable by providing at those places adequate quantities of fresh circulating air."

Nov 1, 1923

By M. H. Rana

"A survey of our knowledge in the field of rock mechanics is presented from the viewpoint of applications in the mining industry. Aspects of rock mechanics of special interest to the industry are enlarged upon, with emphasis on the avoidance of over-generalization. The relationship between fundamental and practical rock mechanics is discussed, and the need for cooperation between the university and industry to further our knowledge of -useful rock mechanics is emphasized. An attempt has been made to establish the scope of rock mechanics, as applied to problems in the mining industry. This is brought about by projecting rock mechanics as a tool to be intelligently used rather than magic, capable of producing ""miracles."" Continued education is important for individuals engaged in the application 0f rock mechanics in the mining industry. The scope of this education is discussed from a viewpoint of better communication between industry and the education and/or re-search establishments engaged in this work.Finally, the dangers of over-emphasis on rock mechanics are mentioned, but a justification of the in-vestment in rock mechanics programs in mines is also presented."

Jan 1, 1966

By J. D. Noll

An effective technique to minimize miners? respirable dust and diesel exposure on mobile mining equipment is to place mine operators in enclosed cabs with designed filtration and pressurization systems. Many factors affect the performance of these enclosed cab systems, and one of the most significant factors is the effectiveness of the filtration system. High-efficiency particulate air (HEPA)-type filters are typically used because they are highly efficient at capturing all types and sizes of particles, including those in the submicron range such as diesel particulate matter (DPM). However, in laboratory tests, minimum efficiency reporting value (MERV) 16 filters have proven to be highly efficient for capturing DPM and respirable dust. Also, MERV 16 filters can be less restrictive to cab airflow and less expensive than HEPA filters. To verify their effectiveness in the field, MERV 16 filters were used in the enclosed cab filtration system on a face drill and roof bolting mining machine and tested at an underground limestone mine. Test results showed that DPM and respirable dust concentrations were reduced by more than 90% when the cabs were properly sealed. However, when the cab door was opened periodically throughout the shift, the reduction efficiency of the MERV 16 filters was reduced to 80% on average.

Feb 1, 2014

By Stephen Krickovic

A degasification experiment was conducted in a Pocahontas No. 3 coalbed mine in Virginia. It involved (1) drilling holes in the coalbed in the out-side headings of a set of five being developed in virgin area, and (2) con-ducting a methane emission rate study as mining progressed and additional holes were drilled. Degasification from all drill holes except the longest in each of the outside headings and the first three drilled (excluding the in-situ pressure hole), was erratic and inconsequential in methane emission rates. The two longest holes liberated 66 and 79 cfm of methane, which is significant for the coalbed, but such quantity lasted a relatively short time; the first three were uniform but low in methane emission.

Jan 1, 1972

By Briggs H.

The illustrated device uses the principle that the lamp can burn with a smaller inlet passage if the air is rich in O2 and that the size of the inlet can be made a measure of O2 percentage. The appliance consists of an adjustable cut-off applied to the inlet of a safety lamp of the improved Gray pattern. Precision is assessed from tables of calibration tests in air contaminated with blackdamp of CO2:N2 composiiton 1:5.67 at temperatures of 40-70 degrees F. Results are presented of tests at St. Germain's colliery, of tests in air contaminated with pure CO2 and of air contaminated with both blackdamp and inflammable gas; published ranges in mine-air blackdamp compositions are tabulated as ranging from 90.06% N2 to 43.90% CO2. When firedamp is present at 1.25-2.5%, its content must first be estimated by means of the cap and a fifth of its value then deducted from the lamp reading for O2

Dec 1, 1916

By J. Drimmer

The past several decades have seen the rapid expansion of multinational mining companies? exploration and production activities around the globe. This trend has resulted from a number of factors, including increased demand for resources as a result of worldwide economic growth, the diminishment of known and proven reserves, rising commodity prices, technology improvements, and the liberalization of investment regimes in developing countries with significant natural resources. With those opportunities, however, come associated risks and significantly increased legal compliance obligations that may be imposed by various bodies. That includes domestic regulations, as well as foreign civil and criminal laws with extraterritorial reach. A failure to adhere to those laws can have dire consequences, including substantial monetary fines and penalties, severe damage to a company?s reputation, and even jail time for individual company employees.

Jan 1, 2010

By Morley H. Mathewson

The unprecedented demand for capital investment in the mining industry today has intensified management's interest in every known technique which will help to reduce operating costs and increase production. One proven approach leading to the accomplishment of this objective is well known in the mining industry and is gaining added prestige, particularly where keen competitive conditions exist. This approach is in the area of incentives applied to mining productivity. An investigation of many incentive plans now in use throughout the mining industry revealed a predominant number of conventional type plans, Most of these plans are designed to reward the hourly-paid employee on the basis of percent over and above a standard hourly or daily ton rate, By contrast, this search failed to divulge any incentive plan solely and independently developed for production management employees. This does not mean that such plans in the mining industry are nonexistnet, but it does indicate that production management incentive systems are scarce or are being kept under wraps.

Jan 1, 1960