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By Thomas T. Read

AT this time of the year, engineering schools are releasing a group of young men who probably are, on the average, in much the same attitude of mind as a person arriving at the terminal station of a railway journey; namely, of having a general idea of his objective, but having to make a decision as to just where he is going and how best to get there. The man leaving the train can at first follow the crowd, but it soon breaks up, as one goes one way and one another, until he has to choose his own course. The recent graduate may do the equivalent of following the crowd by accepting the first position offered, but this only postpones a decision as to where he is going and how best to get there. So many young engineers ask for advice as to what to do that the following statement has been prepared as an attempt to make a general answer to such queries. The engineer taking his first job should realize two fundamental relations. The first is that in electing to be an engineer he has elected to be a hired man. A consulting engineer has more freedom than a man on a regular pay roll, but he is also a hired man; hired for briefer periods at a relatively high rate, but under the necessity of simultaneously doing his consulting work and developing new retainers. There is nothing derogatory in being a hired man (all doctors, lawyers and clergymen are hired men), but the tardy realization that he is one seems to give many an engineer a mental jolt that can be avoided if he accepts it from the beginning.

Jan 1, 1926

By B. Hester

Many Third World countries of Third World Africa are well-endowed with minerals, especially gold. Political and economic conditions discouraged interest by Western capital for the several decades since colonial rule. Influence from Eastern Block countries has gone and the left wing orientation widely favored by Third World countries has almost disappeared. Under International Monetary Fund influence, these countries now solicit Western finance to expand their industries. Mining is especially encouraged. The paper describes the financing of some recent developments and examines trends and opportunities in some of the more attractive countries.

Jan 1, 1993

By S Wright, W Bruckard

The current status of battery collection and recycling schemes in Australia are explored in light of current developments in product stewardship and increasing pressure to decrease materials going to landfill by originating equipment manufacturers. Used consumer batteries, both single cycle and rechargeable contain a mixture of valuable metals and potentially toxic materials that may become a resource/revenue stream to offset the cost of disposal/recycling. Although the volume of batteries discarded in Australia is modest compared to other global population centres, the expected increase in battery use with increasing equipment portability and future developments in the automotive industry, provide an opportunity to recycle. The requirements for a battery recycling facility in Australia and the most promising processing platforms that may exploit the resource with enough flexibility to cope with battery developments and market trends, are explored.

Jan 1, 2006

AS If see it, then, the engineering advances of which yob have studied here at Golden, the continued growth of. industry that you see about you here in Colorado, and the country-wide progress that I have not time to discuss-these illuminating facts should clear away any doubts as to your future. You have little license to ask, "Where is the call for engineering or what the need? Yankee fashion I might ask you by way of reply, "Have all the mines been opened? Have all the power-houses and transmission lines been built? Have the last improvements in. mill and smelter been in-stalled?" We know that the general answer is No, and the rest of the answer, which tells where are those mines and power plants and what are the new methods and processes in mining and metallurgy, must be sup-plied by you engineers of the future. And anyone who has even casually observed what recent years have brought forth in our profes- sion cannot but envy you your job. Our reconnaissance excur-sion into your future should not be much longer extended, but before turning back there are four landmarks that I would like to point out-not lofty peaks but useful tie points that are worthy of your attention as you traverse the territory of your future work. Two of these are in fact low spots or depressed areas which call for engineering activity; these are commonly called "waste" and "average." The other two are of larger significance and are rather extensive regions in the domain you are to enter and occupy. These larger tracts bear the suggestive place names "fact-finding" and "human engineering" and perhaps will prove to be the heights from which the broadest outlook is to be had in this "pilgrim's progress:" In the first place, waste deserves your attention, al-though I realize that it is possibly the most unpopular word anyone hailing from Washington can publicly utter. Its unpopularity naturally follows from its overuse in the somewhat strong charges made against the industrial and business world some years ago, when the doctrine of conservation was first preached in the land. But waste is a word to be used in an engineering sense as well as for political effect. Properly used, waste is not a word to shy at-rather it is a challenge to the engineer. For example, at present, the loss of 1 kilowatt-hour to every 5 sold is a clarion call to the electrical engineer. Waste is your target to shoot at, the obstacle for you to surmount, the giant for you to slay.

Jan 7, 1928

By Joseph Goodwill

1. PURPOSE The objective of this paper is to summarize a study undertaken by the EPRI Center for Metals Production (CMP). The overall purpose of the study was to identify electrolytic opportunities that might merit consideration for joint development by industry and EPRI. 2. SCOPE The electrolytic technologies of interest to this study include: Electrorefining, Electrowinning, and Fused-salt electrolysis. Recovery from primary, secondary, and waste materials were included in this effort; however, we excluded from consideration: Plating and coating operations, such as electrogalvanizing; Mining and milling operations in which electric energy is predominantly used for comminution; Electrothermal processes in which submerged-arc, open electric-arc, and plasma-based smelting processes use electric energy largely to provide a melting or refining ("heating") capability; and Aluminum electrotechnologies since these were the subject of a separate study (CMP 86-2). We recognize that there may be some "gray areas" between these excluded areas and the electrolytic sectors of interest. For this reason, a secondary criterium was used, namely, if the major use of electric energy was to extract or refine the

Jan 1, 1990

Thank you for the opportunity to speak at this important conference attended by aspiring mining professionals, some of whom will become the leaders of the mineral resources industry that forms the solid foundation of AustraliaÆs past and that will fuel the exciting growth of AustraliaÆs future.I want to briefly touch on the history of our business, then look at the opportunities that exist in the contract mining industry and finally comment on what the educators need to consider in their curriculum to meet the needs of our business. Byrnecut started out as an idea in early-1987 developed by a group of four mining people. At the time the industry was on the high end of a mining boom, the era of the Bonds, Connels, Skases and so on. Riding on this wave of euphoria we borrowed $600 000 from the National Australia Bank and, without having enough knowledge to lose sleep over the potential risks, started business in mid-1987. The euphoria quickly evaporated with the 1987 October stock market crash. The bank pulled our overdraft, equipment finance rates increased to over 20 per cent per annum and my house was mortgagedseveral times over. The business learning curve was extreme for a young mining engineer who had developed his trade in the relatively sheltered environment of a large public mining house, namely WMC. We were somewhat bitter that the banks had done a runner. We were a private company, backing the business with personal assets with our shoulders to the wheel, whilst the Bonds of the world had theirnoses in the trough ripping off mum and dad shareholders. All of this had a sobering effect, namely keep your feet on the ground, stick to the knitting, work hard and worship cash flow. Since that stressful but adrenaline pumping beginning the company now employs over 600 people and is now working for major mining houses at over a dozen locations in Australia, east Africa and WesternEurope and the National bank is again our banker. On this basis I consider myself qualified for the subject of this speech.

Jan 1, 2002

By C J. Larder, S E. Turner

The concept of underground grinding is not new, but to a metallurgist and a mining engineer this could be considered unconventional. The idea of pumping a ground slurry several hundred metres from underground in a single lift could also be considered to present a daunting engineering challenge. Using a practical example of a mine in Australia where the owners have requested not to be identified, this paper challenges the conventional thoughts on these concepts and shows that with basic sound engineering practices the production of a ground slurry from underground could potentially provide significant operating cost savings. The supply of ore from the underground mine is currently drawn from depths approaching 800 m below the surface. The cost of hauling the ore to the existing underground crushing station located 500 m below surface has been steadily increasing. A number of alternatives to reduce the mining and processing unit operating costs were examined by Sinclair Knight Merz (SKM) and the mining company. The most radical of these is the use of hydraulic hoisting of ore at an increased production rate. Numerous questions were asked, such as: How does one get a SAG mill or an HPGR crusher underground? Where does one locate a grinding mill underground? Does the technology exist to pump the slurry to surface in a single lift? What will be the cost benefits? What are the risks involved? The study covered the two main technical issues underlying the potential benefits. Firstly, technical evaluations were undertaken on the pumping technology currently available for single and multiple lifts to surface. Secondly, the issues relating to the feasibility of delivering and locating a SAG mill underground were reviewed. Although the capital costs for this project are significant, the operating cost savings showed a potential payback period of less than two years, and furthermore provide the basis for an increased mine life, especially at lower metal prices.

Jan 1, 2005

By SAMUEL GOMPERS

THE name engineer makes a very strong appeal to one who appreciates the mechanism underlying the fabric of our civilization. Engineers are scouts of civilization. We send them ahead into the lone 'places-the wilderness, the jungles, the great watery expanses, to build the highways necessary for civilized man. The engineers must deal with Nature, with that mysterious dynamic thing we call "force," with materials. It is their function to direct the human activity necessary to coordinate these forces and material in order to make them serve the needs and aspirations of men. Because of my high conception of the engineering profession I was glad to accept the invitation to address The American Society of Mechanical Engineers to voice my understanding of the possibilities of your work as engineers of industry, and to suggest what seems to me the responsibility of the-engineer to the whole modern industrial system.

Jan 1, 1921

By Scott Turner

IT has been considered that the training of an engineer is too often vocational training; that it is a pity all engineers cannot have had a period of liberal training before taking up' pure engineering. Offhand, the so-called liberal courses should bring more ready adaptability to deal with the unexpected, to face with assurance situations which have had no parallel in one's experience, and to move without hesitation under conditions which were heretofore unknown to one, than the specialized course in mining engineering. We hear increasing talk as to the necessity of making the engineer articulate and bringing him into public life. The social implications, and responsibilities of engineering are pointed out, as of equal importance with the prodigious marvels of engineering ingenuity. You often read of this as the logical result of the in¬creasing consciousness of the engineer as to his rela¬tive position in our modern industrial civilization. , Some wag has noted that man is the noblest work of God, but that man is the only one who has said so. Perhaps engineers are the only claimants as to the necessity of their going in for public life and service; at any rate, some liberal educators' still maintain that a well-rounded general education is the better training.

Jan 1, 1930

By Paul Pugsley

The need for dimensional measurement of products has always been there, now with the industry 4 push to further understand measure and to record process parameters is more important than ever. This applies to both flat and long products, camera systems have always provided the method to measure, stereo Linescan cameras for flat products and innovative applications using 2D and Linescan cameras for long products. Instrumentation will become more important to producers enabling processes to be better controlled and understood, that aim being to make the production process understandable more repeatable and less reliant on operator influence. Primetals Technologies Ltd offer solutions for all types of products.

Oct 30, 2017

By Willy Persson

A common feature of the kinds and amounts of impurities present most pyrometallurgical, processes is injection of oxygen to, remove various in the feed. The degree of success of a specific process step relies critically on control of the instantaneous oxygen potential/oxidation stage, throughout the step as well as upon termination of the step. This will, for instance, determine the distribution of impurities between metal and slag. As long as the operation is perturbation free -detailed analysis of all additions and application of advanced models often yield satisfactory control means However, a pyrometallurgical process is seldom free from disturbances, which reduces the accuracy of the static models and leads to inconsistencies in scheduled route might be uncontrollable changes in quality and quantity of feed, operator interventions and shift changes, timing of cranes, lining wear and accretions etc. The implementation of dynamic, control to correct for disturbances and, more generally for process optimization, requires continuous on-line information on, the actual status of the process. The implementation of sensors for continuous process monitoring, e.g., as regards the instantaneously prevailing oxygen potential or oxidation stage, has been hampered by the highly aggressive environment in smelters; This is. where remote-sensing techniques based on optics and spectroscopy, have proven to form invaluable, tools towards the realization of dynamic production control. Since about 15 years Semtch has developed and industrialized a remote-sensing technology, based on ,optics and spectroscopy, for continuous on-line process monitoring and production control of various pyrometallurgical processes. The presentation will discuss applicability aspects with examples and experiences from installations and tests in ferrous and non-ferrous industry. Keywords: Applied spectroscopy, Metallurgy, Process monitoring, Production. Control

Jan 1, 2003

The capability for on-line measurement of the quality characteristics of conveyed coal now enables mine operators to take advantage of the inherent heterogeneity of those streams and split them into wash and no-wash stocks. Relative to processing the entire stream, this reduces the amount of coal that must be washed at the mine and thereby reduces processing costs, recovery losses, and refuse generation levels. In this paper, new approaches for optimal control of the segregation process, using time series models and empirical distributions, are presented and demonstrated using field data.

Jan 1, 1998

By Rodney L. Williamson

Optimal estimation theory has been applied to the problem of estimating process variables during vacuum arc remelting (V AR), a process widely used in the specialty metals industry to cast large ingots of segregation sensitive and/or reactive metal alloys. Four state variables were used to develop a simple state-space model of the V AR process: electrode gap (G), electrode mass (M), electrode position (X) and electrode melting rate (R). The optimal estimator consists of a Kalman filter that incorporates the model and uses electrode feed rate and measurement based estimates of G, M and X to produce optimal estimates of all four state variables. Simulations show that the filter provides estimates that have error variances between one and three orders-of-magnitude less than estimates based solely on measurements. Examples are presented that verify this for electrode gap, an extremely important control parameter for the process.

Jan 1, 2001

An important problem in mine operations is the classification of material as waste, low-grade stockpile, and ore. This classification must often be made with blasthole data that are widely spaced and that have sampling errors. Geo-statistical simulation techniques combined with basic economic principles allows a procedure for classification that maximizes expected profit. Geostatistical simulation methods (Gaussian, indicator, or annealing-based) allow the integration of hard and soft data in the creation of alternative, equally-probable, realizations of the mineral grade(s). At each location, for each realization, we calculate the "profit" if the block were to be classified as ore or waste The optimal classification is the one that maximizes expected profit (a Maximum Profit Se-lection (MPS) procedure). We discuss the theoretical justification of the method and implementation details. The use of blasthole data from different types of mineral deposits, that is, different levels of continuity, is considered. We also show the efficacy of the procedure with different levels of sampling error. The increased revenue due to the MPS procedure and improved sampling is shown. We show the geostatistical simulation procedure and the uncertainty in block grades that result from incomplete and imperfect sampling. The optimal classification is presented. Optimal block classifications are transferred to realizable dig-limits by hand-drawing polygonal boundaries. We compare the results of the proposed method to classification based on kriging. Limitations and areas of future work are identified.

Jan 1, 1999

By Felipe Costa Hashimoto Bertin, Jorge Alberto Soares Tenório, Rodrigo de Souza Dalti Pereira, Denise Crocce Romano Espinosa

"The increasing amount of portable devices and their fast obsolescence generates an increasing quantity of discarded batteries. The recycling process of discarded batteries allows the recovery of metals for further use and avoids the contamination of soil and water. Even though there are several researches on the topic, few papers focus on mixed batteries. The purpose of this work is to characterize a mass of collected mixed batteries and study the hydrometallurgical process of recycling. The specific leaching parameters studied were pH, temperature and reduction potential. The specific goal was testing the selectivity of pH for leaching each metal. The results show that the optimal leaching occurs in acid solutions with negative pH at IM of sulfuric acid and at room temperature (25°C).IntroductionThe increasing portability of electronic devices in the past century along with their fast obsolescence produce tons of discarded materials yearly that could be recycled generating new materials for the industry. For example, metals such as cobalt and nickel, that are worth respectively US$ 30.00 and US$ 16.10 per kilogram[l,2] are disposed in urban trash yearly, which means that millions of dollars are thrown away instead of being recovered and reused[3].Besides the obvious fact that the society is throwing money away, most of these metals are toxic for the environment and all mammals, so when badly stored after use they can be found contaminating ground water which will contaminate the entire lifecycle. Some of these metals can cause cancer, serious lung problems and have bioaccumulative properties [4] resulting in lower productions of natural products and maybe death for consumers.So in compliance to new regulations such as the National Solid Residue Politic (PNRS) and the CONAMA-Resolution N°401 from November of 2008[5]- (that follows similar restrictions and regulations as the European directives) all those urban and electronic wastes need to be correctly disposed and treated before being thrown away on local dump sites.In Brazil the national rate of garbage recovery is around 70%, which only 5% is properly recycled, accordingly to the research of the UFSC, also electronic waste grows at 5% per year [6]The present study was motivated by the fact that recycling processes for batteries are not spread through the country and by the fact that most papers do not try to recycle a mixed mass of batteries, but a specific mixture which does not represent the composition of traditional household wastes."

Jan 1, 2014

By M Forbes, R Jeuken

Brownfields geoscience measurement such as drilling and surface geophysics can be costly and it is often difficult to weigh the cost of data collection and processing against the value it unlocks at the time of extraction. This makes it difficult to prioritise geoscience expenditure and find the optimum intensity of geoscience activity across competing assets. There are multiple options for managing resource uncertainty and spatial variability through mine planning and resource engineering such as varying marketing strategy, adjusting stockpile or other infrastructure design and product blending. Consideration of these alongside increased data collection further complicates finding a comparable value of geoscience programs to determine the right blend of geoscience measurement and engineering controls. Concepts similar to Value of Information (VOI) analysis which is applied to strategic planning can be used to estimate the value of geoscience measurement and pit sequencing at tactical planning and operational timescales. This involves the quantification of resource uncertainty and prediction of how it will affect resource extraction. This paper outlines this process and demonstrates its use to prioritise geoscience at BHP Coal Assets. The value of infill drill programs in enabling operational stability is quantified and compared the value of engineering controls like increased stockpile capacity. This study supports that idea that the application of VOI methods to bulk mining at tactical time horizons has potential to inform geoscience planning and resource engineering not just separately, but as part of a unified strategy for managing resource uncertainty.

Mar 22, 2022

By Alessandro Navarra, Roberto Parra, Boyd Davis, Frank Mucciardi

A smelter scheduling algorithm has been developed, which allocates the oxygen production between the smelting furnace and the converter aisle, so as to maximize copper throughput. The algorithm is intended for daily operation planning, controlling the sequencing of the converter cycles, and the oxygen drawn by these cycles. In some cases, it may be worthwhile to decrease converter oxygen allocation in favour of the smelting furnaces. Thus, a better utilization of the oxygen plant can increase primary copper throughput by several percentage points. This principle is demonstrated through sample computations. The approach presented in this paper can be incorporated into smelter management software.

Jan 1, 2015

By G. ALBORNOZ, S. Utili, A. AGOSTI, C. VALDERRAMA, R. PELL, N. Morales

The steepness of the slopes of an open pit mine has a substantial influence on the financial return of the mine. The paper proposes a novel design methodology where overall steeper pitwalls are employed without compromising the safety of the mine. In current design practice, pitwall profiles are often planar in cross-section within each rock layer; i.e., the profile inclination across each layer tends to be constant. Here instead, a new geotechnical software, OptimalSlope, is employed to determine optimal pitwall profiles of depth varying inclination. OptimalSlope seeks the solution of a mathematical optimization problem where the overall steepness of the pitwall, from crest to toe, is maximized for an assigned lithology, geotechnical properties, and factor of safety (FoS). Bench geometries (bench height, face inclination, minimum berm width) are imposed in the optimization as constraints which bind the maximum local inclination of the sought optimal profile together with any other constraints such as geological discontinuities that may influence slope failure. The obtained optimal profiles are always steeper than their planar counterparts (i.e., the planar profiles exhibiting the same FoS) up to 8° depending on rock type and severity of constraints on local inclinations. The design of a copper mine is first carried out employing planar pitwalls, secondly adopting the optimal pitwall profiles determined by OptimalSlope. The adoption of optimal slope profiles leads to a 34% higher net present value and reductions of carbon footprint and energy consumption of 0.17 Mt CO2 eq and 82.5 million MJ respectively due to a 15% reduction of rockwaste volume.

Feb 9, 2022

By G. ALBORNOZ, S. Utili, A. AGOSTI, C. VALDERRAMA, R. PELL, N. Morales

The steepness of the slopes of an open pit mine has a substantial influence on the financial return of the mine. The paper proposes a novel design methodology where overall steeper pitwalls are employed without compromising the safety of the mine. In current design practice pitwall profiles are often planar in crosssection and the profile in between ramps especially tend to be planar and defined by a constant inter-ramp angle. Sometimes rock layers exhibiting different strengths require the inclination of the profile to vary with depth, but the inclination across each layer is usually constant. Here instead, a new geotechnical software, OptimalSlope, is employed to determine optimal pitwall profiles of depth varying inclination. OptimalSlope seeks the solution of a mathematical optimization problem where the overall steepness of the pitwall, from crest to toe, is maximized for an assigned lithology, geotechnical properties and Factor of Safety (FoS). Bench geometries (bench height, face inclination, minimum berm width) are imposed in the optimization as constraints which bind the maximum local inclination of the sought optimal profile together with any other constraints such as geological discontinuities that may influence slope failure. The obtained optimal profiles are always steeper than their planar counterparts (i.e. the planar profiles exhibiting the same FoS) up to 8 degrees depending on rock type and severity of constraints on local inclinations. The design of a copper mine is first carried out employing planar pitwalls, secondly adopting the optimal pitwall profiles determined by OptimalSlope. The adoption of optimal slope profiles leads to a 34% higher net present value and reductions of carbon footprint and energy consumption of 0.17 Mt CO2 eq and 82.5 million MJ respectively due to a 15% reduction of rockwaste volume.

Mar 2, 2022

By C. Guria

A modeling, simulation and optimization study of a complex industrial fluorspar beneficiation plant (Kadipani, Gujarat, India) with fourteen/ten flotation banks is carried out to find an optimum/near-optimum circuit for the given quality of feed ore. The phenomenological flotation model developed by Mehrotra and Kapur (1974) is used for circuit optimization. Two different optimization problems are formulated and solved. The first optimization problem involves a single objective function, which uses available plant data to estimate the feed-characterizing parameters, i.e., the flotation rate constants, by minimizing the weighted sum-of-square errors between the computed and plant values. The second optimization problem involves two objective functions to obtain several simplified circuits. The number of non-linking streams and the overall recovery of the concentrate, i.e., the acid-grade product, are maximized simultaneously in this problem. The single-objective variant (SGA-II-mJG) of the binary-coded elitist non-dominated sorting genetic algorithm with the jumping gene adaptation, NSGA-II-mJG, is used for the first problem, while NAGA-II-mJG (Guria et al., 2005 a) is used for the second problem. Simplified circuits with a few split streams are proposed on the basis of the present optimization study, which enhance the recovery of the acid-grade product without affecting its quality, for a given total volume of the flotation cell-bank. Even though the optimal solutions have certain drawbacks, they suggest a meaningful direction in using an iterative fitting of parameters to such optimal circuits, followed by re-optimization. Key words: Froth flotation, Mineral processing, Industrial fluorspar beneficiation, Feed identification, Circuit/network optimization, Global optimal, Jumping gene, Genetic algorithm, Multi-objective optimization

Jan 1, 2009