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The Shortage of Mining and Metallurgical Engineers I N many parts of the Western World attention has recently been drawn to the acute shortage of mining and metallurgical engineers produced by the universities. Naturally, the reasons for this shortage have been discussed, and various remedies for it have been proposed. In this paper, I want to examine some of them. It is now fairly generally ac-cepted among mining men that the easy attractions of modern urban life have left the career of mining in the metaphorical as well as in the literal backwoods. The industry finds it increasingly difficult to recruit adventurous and intelligent young men; for such men now seek their intellectual, if not physical, adventure in more glamorous occupations from a safe social base in suburbia. The salaries, opportunities and security offered by the mining industry do not complete effectively with the rewards offered by other industries and by commerce, taking into account the social disadvantages of a mining life. The excitement and other non-material attractions of mining

Jan 1, 1965

By P. B. Bucky

IN this day of steady progress in the mining industry, especially along mechanical lines, the question of whether to discard present equipment for that of a new type often engages the minds of many officials of mining companies. The rapid strides made from year to year sometimes cause this question to be brought up within a year after new equipment has been purchased and installed. It is a moot question whether a machine that has been purchased last year should be replaced by a new one put on the market this year. As I see it, the reasons for the replacement of present equipment may be summed up as follows: (1) because of increased safety; (2) because of legal regulations; (3) because of increased profits. I think all of us, as engineers, will endeavor to put in as safe equipment as it is possible to devise. The tendency of mining companies in that direction is very gratifying.

Jan 1, 1930

By Daniele Tolazzi

Electric Arc Furnaces keep evolving into highly powerful melting units, shrinking taptotap times by increasing the effectiveness of the energy sources and the material fluxes used in the process. Steelmakers are targeting to increase the efficiency of their injection package in order to reduce the overall conversion costs, seeking for technologies specifically designed to promote the metallurgical reactions in a predictable and reproducible process automatically controlled at the correct timing. Many technological enhancements have focused in the gas management, improving the burner design and the penetration capacity of oxygen injectors, dedicated to decarburization and the other exothermic reactions. Instead, lower evolution efforts have been addressed to engineered solutions for managing the addition of solid materials required in slag forming, although they are playing a key role in EAF process optimization, as well. The paper describes the latest solutions designed to manage efficiently the injection of fuel, oxygen and powdered materials in several EAFs and presents the operational results achieved. Accurate control of reliable additions of coal, lime and magnesia proved crucial for the control of the slag FeO and viscosity, generating stable foamy slag and producing cleaner steel.

Aug 17, 2017

By Masaru Sakakibara, Ngo Tuan Anh, Mitsuo Nozu

"In the southern region of Vietnam and the southern United States, numbers of Deep Mixing (DM) columns have been installed to increase the stability of slopes and mitigate ground settlement. However, in some cases, there were some quality problems for in-situ cement mixing such as inclusion of unmixed lumps. According to the investigations by the X-ray diffraction analyses, electrical conductivity (EC) test, and careful observations of in-situ mixing quality, it has been observed that the existence of expansive soil and its high EC value cause the insufficient in-situ mixing. The countermeasures to address these problems have been taken.INTRODUCTIONIn South Vietnam, under the guidance of numbers of references and standards (Miki, 1998, JGS, 2000, Kitazume et.al., 2001, BS 2005), Deep Mixing (DM) has been used in recent years for soft clay improvement to increase the stability of slopes and to reduce consolidation settlement (Nozu 2005, Tung et.al., 2009, S. T. G. Peng et.al, 2009). However, at the initial phase of the DM operation, the authors have encountered some unusual phenomena such as (1) lower strength and inclusion of unmixed lumps (Figure 1), (2) less amount of up-heaved soil, and (3) sticking of large lumps of clay to the mixing blades. In regard to the above (3), Photo 1 shows one of the countermeasures against the sticking. By means of the placement of additional plates, the stuck clay has been reduced significantly.Subsequently, we have noticed that the quality of DM columns has not been so good, which meant that there have been some unmixed lumps in the column despite high cement dosage such as more than 300kg/m3. The authors also have encountered the similar incidents in Vietnam and United States during the deep soil mixing work. For example, Photo 2 is the core samples taken from the DM test column in northern Vietnam adopting cement injection during penetration (CIDP) procedure. To solve this problem, various tests and investigations have been performed so far (Nozu 2010, 2012)."

Jan 1, 2015

By P. M. Swash

The paper describes the use of mineralogical methods in the exploration and evaluation of primary diamond occurrences. The most common methods that are used include the systematic search for kimberlitic indicator minerals, surface textural study of the indicator minerals, (garnet, spinel, ilmenite and chrome diopside) and alluvial macrodiamond studies so as to understand their provenance and guide exploration towards diamondiferous targets. The mineral chemistry of the indicator is used to positively assess the origin of the mineral grains and is also pivotal in the determination of the diamond potential of a deposit. Petrography of the primary deposit is able to identify the body to be kimberlitic and is also a support to the mineral chemistry findings. Unambiguous proof of a prospects potential to contain macrodiamond is proven by the occurrence of microdiamonds in the residues from the rock. The presence of a sufficient number of microdiamonds in the rock is enough to determine a semiquantitative grade estimate and warrant further metallurgical evaluation so as to determine its actual macrodiamond content.

Jan 1, 1991

By C. Ntsele

Stirred milling technologies have firmly established themselves in concentrator circuits as energy-efficient alternatives to tumbling ball mills. High and continued increases in electricity costs, coupled with the ever-increasing power consumption by primary grinding circuits due to declining head grades of ore-bodies, provides a compelling case for these technologies. Additionally, the ability to successfully deploy stirred milling in coarse grinding applications extends the range of use in concentrators, thus increasing the opportunity matrix for energy optimization in a flowsheet. This paper therefore details methodologies and strategies that can be applied to evaluate the optimum stirred milling solution for different concentrator applications. These methods and strategies will focus specifically on the two major stirred mill machine types; namely, gravity-induced (VERTIMILL? grinding mill and Nippion-Eirich tower mill) and fluidized (SMD, Isamill?, Knelson-Deswik mill, etc. ). Finally, case studies from circuits across industry and laboratory tests will be used to illustrate the energy benefit from the use of stirred mills.

Jan 1, 2012

In preparing a paper such as this it was thought that the Newstan Colliery Company Ltd., being comparatively new, would need some introduction to mining people in general.The Newstan Company was formed by the Joint Coal Board in December, 1948 during a period of acute coal shortages. The Company took over the holdings of what were known as the Olstan and Northumberland Collieries, situated at Fassifern, alongside Lake Macquarie and adjacent to the Great Northern Railway, within easy rail access of Sydney and Newcastle, as shown on the locality plan (Fig. 1).The Company was developed in order to produce steaming coal for the power house trade and has continued its activities in the steaming coal trade since its inception. The Olstan and Northumberland collieries were together producing some 300 tons per day when the Company was formed, and it was from this foundation that the colliery was built. The planned development of the Company has been along the lines of producing coal by modern, highly mechanised methods, together with the preparation of theproduct for the consumer, to the highest degree possible consistent with up to date methods.In the comparatively short time of 5t years the mine has developed from a small hand-won coal unit to a high capacity modern mine, one of Australia's largest producers, with an output capacity as high as 3,000 tons per shift.

Jan 1, 1954

This listing of members is arranged to show company affiliation The primary breakdown is by state or country, then by company name and political subdivision At the end of each major group is a general list showing members affiliated with schools or colleges and those who did not indicate any company affiliation The listing, for countries outside United States, is broken down generally by continents and alphabetically within the continent by countries The various countries are indexed on the preced¬ing page *-The asterisk indicates members available for consulting work Anyone desiring to be listed with AIME as available for consulting work can do so by sending a written request to the office of the Secretary.

Jan 1, 1952

By Ferdinand Roehlich

An evaluation of the use of manually activated, installed,. dry chemical fire protection systems on underground metal and nonmetal mine vehicles is described. In addition, an assessment of the possible health risks posed by the dry chemical extinguishing agents used in such systems is provided. Work involved installation of fire protection hardware on an operating piece of underground metal/nonmetal mine equipment and, via actual fire tests, a determination of the effectiveness of the hardware in extinguishing on-vehicle fires. Two fire protection systems were installed on a Caterpillar 988 front-end loader in St. Joe Mineral's Fletcher mine, near Viburnum, Mo. Both a fully pressurized Safety First CM-20 and a nonpressurized cartridge actuated Ansul A-101 were installed for comparative purposes. Both systems operated satisfactorily during an 8-month endurance trial period which preceded the actual fire tests. Each system was able to extinguish an 18" x 4" class B test fire placed in the engine area of the machine. The health hazards analysis of dry chemical powder consisted of a detailed search of published literature relating to these multipurpose agents. This data was verified via a controlled laboratory analysis of two monoammonium phosphate based powders (Safety First Unikem and Ansul Forey) and an analysis of air samples collected at various locations on the test vehicle during the fire tests. Although the powder was found to be nontoxic, two potentially dangerous thermal decomposition products were identified--ammonia and phosphoric acid. However, later analysis indicated that an operator would not be exposed to dangerous concentrations of either compound if he were to remain outside of the powder cloud. A "Selection and Use Manual for Manually Activated, Fixed Fire Suppression Systems on Underground Metal and Nonmetal Mining Equipment" was prepared both as an, appendix to the report and for distribution under separate cover.

Jan 1, 1977

By Henry N. McCarl, John J. Dran

The academic community and the larger and more sophisticated mining companies have largely rejected the older mineral valuation methods such as the Hoskold and Morkill concepts and replaced them with "discounted cash flow" (DCF) techniques. The relevancy and usefulness of the older methods have been questioned primarily on the basis of their underlying assumptions that mining companies do not have numerous alternative investments and must use sinking funds deposited at market or "safe" rates of return to recover the purchase price of mineral reserves. The ability to reinvest in numerous (often nonmining) alternative business ventures, the changing purchasing power of the dollar, corporate income and other taxes, depreciation and depletion allowances, and modern financial management practice all militate against the continued use of the older valuation methods, especially for the larger mining companies. Small mining companies and individuals still use these methods largely out of habit and familiarity. The Hoskold Mineral Reserve Valuation Method The Hoskold method was developed prior to the evolution of modern accounting practices and before the days of the corporate income tax. At the time of its development, annual earnings of the firm were represented by the difference between cash revenues and cash expenses and were not subject to taxation by the government. Thus, earnings at that time were equivalent to what is today known as cash flow.

Jan 7, 1974

By Ralph H. Sweetser

N Greenup and Carter counties, in the northeastern part of Kentucky, are the remains of many old charcoal furnaces built and operated during the period from 1818 to 1892. They were all included in what was called the Hanging Rock district. In the summer of 1930 I visited ten of these old blast furnaces, as follows:

Jan 1, 1931

Compagnie Minière Espérance mines a primary gold orebody in an openpit. The ore is processed through crushing, primary gravity concentration, grinding and secondary gravity separation, generating tailings with remaining fine gold. Analysis of the material in the pond has indicated a residual gold grade sufficient to justify a chemical treatment process to recover the gold. However, direct cyanidation would require a prohibitively large installation for the site, which is located in a remote rainforest environment. It was decided to test the feasibility of preconcentration using flotation. As lab tests proved up the technical feasibility of the flotation process, an on-site pilot operation was carried out to assess the continuous circuit performances, define the best configuration and obtain enough data for industrial circuit sizing. Data collected during the pilot campaign was used for calibrating a process simulator built with the USIM? PAC software. The simulator validated the feasibility of upgrading the existing plant, including the reprocessing of tailings to obtain an acceptable fine gold recovery from a small amount of concentrate.

Jan 1, 2010

The contractor examined L.T. White's Patent No. 3524680 and, finding it in need of engineering refinements, proceeded with a conceptual design of a variable wall mining machine. The contractor then proceeded to assess the feasibility of the variable wall mining machine measured against the criteria specified by the U.S. Bureau of Mines. The feasibility was judged from a physical aspect, a health and safety aspect, and an economic aspect. The Variable Wall Mining Machine was judged to be feasible on all three aspects provided that certain specified practices were adopted. Description The specifications and design and performance parameters of the Variable Wall Mining System as conceptualized are summarized in Tables I and II. The system consists of a side-cutting auger operating in a string of identical 12 ft. sections, along a 500 ft. retreating longwall face. In addition to the 41 identical sections, there is a special drive and discharge section at the head gate.

Jan 1, 2012

By Charles E. Green

This study was conducted to identify, evaluate, and develop procedures to minimize or eliminate safety hazards associated with the electrokinetic dewatering process, such as toxic and volatile gas emissions, electrical shock, accidental detonation of explosives, electrochemical corrosion of metal appurtenances, and possibly others. The identification, evaluation, and procedure development were based on pertinent literature, existing safety regulations, interviews with mine personnel, physical and mechanical properties of the electrokinetic dewatering process, and physical characteristics of the material to be dewatered. The electrokinetic dewatering process was described in detail. Potential safety hazards were identified and evaluated. Procedures and/or safety regulations were developed to minimize or eliminate the potential hazards. It was recommended that the electrokinetic dewatering process when used in deep metal mines be properly monitored to obtain additional information on other potential hazards that possibly exist.

Jan 1, 1979

By G. G. Bowser

THE time has come when, as your President, 1 turn the helm over to my worthy successor. When 1 was reminded by our Secretary that 1 had to prepare an address for this meeting, 1 was at a loss for a subject. In the hope of inspiration 1 perused the records of our Society for some years past. 1 found in these records that many problems in need of solution relative to industry in Nova Scotia were discursively dealt with and that sound thought was given to the solution of these problems, with a natural leaning, of course, to problems pertaining to the mining industry. 1 found also that some of the reasoning was remarkably prophetie. Some of these subjects and problems were: The use of pulverized coal to generate power instead of hydro-electric power; rural electrification; the importance of youth training for an efficient place in industry; the proper marketing of coal; the fuels competing with coal; the need for better in-dustrial relations between employer and employee; better education for success in the social field as applied to industry; and Canadian unity. The issue of some of these copies has been forced upon us by war. For instance, there appears to be no marketing problem for coal, nor does there ? seem to be a marketing problem for anything just at present. The problem of the coal producer just now is supply and transportation. Also, at present, coal fe.ars no competitors, such as oil-and not even hardwood. Many large companies now have an industrial Relations or Personnel Manager and department. Furthermore, we have been compelled of necessity to train our young men, and women also, for both industry and war. However, war does not solve these problems and, with the return to normal times, we may be faced with the same troubles in even greater measure. My reason for mentioning these copies is to point out that, as mining men, we are aU desirous of progress in every industry, not only the mining industry; and that mining men are able to see clearly ahead. In normal times, especially in matters not directly affecting the mining industry, we are inclined to let matters take their own good rime, or let the government do it. We do not seem to realize that these necessary and desirable changes can be made in times of peace-instead of being forced upon us by war or other social upheavals-by the method of sound thought and action to the desired end.

Jan 1, 1943

By Samuel S. Wyer

Discussion of the paper of SAMUEL S. WYER, presented at the New York meeting February, 1916, and printed in Bulletin No. 110, February, 1916, pp. 263 to 279. DAVID T. DAY, Washington, D. C.-I would like to ask whether the court decisions quoted in the paper are general, or do they represent one side of the case; if so, are there any decisions that represent more than one side of the case? Are they of general application, or do they affect only one side? Also, what is the difference between a pump and a compressor from the standpoint of the natural-gas industry? I notice stress is laid on the word "pump" in. connection with some of the legal decisions, and then it is stated. that they must not pump or compress above 300 lb. The question is, is a pump a compressor and a compressor a pump, under certain conditions? SAMUEL S. WYER, Columbus, Ohio.-Answering the first question, I will say that the decisions cover both sides of the case very thoroughly, and are uniformly on the side that a company is justified in the use of gas compressors; in other words, there are no decisions holding it to be illegal to use gas compressors, with the exception noted in Indiana, Kansas, and Oklahoma where you cannot go below atmospheric pressure. In regard to the second question, I think the engineers and the gas operators themselves are responsible for the confusion. It is because the use of the term "pump" is almost universal, and so many people have obtained the idea that the primary function of a gas compressor is to pump air into the gas, in order to increase the consumers' gas bills. I appreciate that it is very hard to draw a clear line of demarcation. between a pump and a compressor. The distinction I have always made myself, and which I think is a logical one, is that you do not get the pumping action until you get below atmospheric pressure. As far as the compression end is concerned, there is only one State, namely, Indiana, that has any statutory limitation with regard to how high the pressure may be increased in order to put the gas into the transmission lines. The State law in Indiana limits the maximum pressure to 300 lb. per square inch.

Jan 5, 1916

By Yun Bai, Sarah Wilson, Michael Salcher, Mark Trim

Over the last decade more than 62 miles (100 km) of civil transport tunnels were constructed in Sydney, Australia, using the sequential excavation method (SEM). The WestConnex motorway tunnels, each stage of which used over 20 roadheaders to excavate up to 40 tunnel headings, had numerous caverns up to 100 feet (30 m) wide and 82 feet (25 m) high. SEM tunnels in North America typically have far fewer active headings. This paper examines the differences in scope and risk allocation for construction phase services, including comparison of the Permit to Tunnel (PTT) process in Australia and the Required Excavation and Support process in North America.

Jun 23, 2024

This paper deals mainly with the modernization in the coal loading system at the loading piers of the Dominion Coal Company, Ltd., Sydney, Nova Scotia. The history of the operation is briefly outlined, and the construction of the Company's new pier is described in considerable de-tail. Particular attention is paid to the bins and conveyors, and to the loading tower. The paper concludes with a description of the S.S. Cape Breton Miner, built specifically for the coal trade, and the unloading facilities at Lakeview, Ontario. Coal Shipping at Sydney C OAL from the mines operated in Cape Breton by the Dominion Coal Company, Limited, has been shipped from the International Piers, situated on the east side of Sydney Harbour, for over sixty years. There were three piers, of which two were active-ly used in the shipping of coal until 1964. Nos. 2 and 3 were high piers about 600 feet long, of wooden construction throughout. They were founded on' rock-filled cribs and creosoted piles driven into the harbour bottom, and each had two decks which carried standard-gauge railway tracks.

Jan 1, 1965

By R. E. Head

[This paper embodies the data obtained by a detailed statistical, microscopic analysis of the composite mill feed concentrate, and tailing from the Magne and Arthur mills of the Utah Conger Co. for 1 month in 1929. It is one of a series of papers by the same authors5 dealing with the mineralogical characteristics of the ore and concentration products from various well-known plants. The work was done in the cooperateive microscopic service laboratory at Salt Lake and represents the results of cooperation between the United States Bureau u of Mines, the Utah Copper Co. and the University of Utah.]

Jan 1, 1935

'Nothing happens until something is sold' This statement is not original - it is a necessary orientation for marketing industrial minerals. The most important single philosophy of marketing is that it recognises the consumer as the starting point. Production orientation is concerned with producing products that the customer might buy. Market orientation is concerned with finding the needs of the customer and how they can be satisfied. The difference between the two approaches can be recognised in company structures but the most tangible difference is in the approach by a company to selling and development. In other words, it is the market that decides what can be done with a mineral. The markets requirements dictate what mineral, what grade and what price will be paid. Therefore it follows that when pricing a product we should avoid taking the basic cost and arriving at a final selling price through a series of standard markups (unless government insists on it). We should start with the price the market can stand and work backwards to find out whether you have a profitable product or one that will fail because it is too dear. Naturally a thorough understanding of production costs is necessary particularly when marginal markets are concerned.

Jan 1, 1978