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By Delbert L. Keenon

The principal concepts of computer control and automation have been successfully applied in industries world-wide, The enthusiasm generated by the proponents of computer control, and the apparent mystery enveloping the techniques of computer control, have caused attention to be focused on this infant industry from all quarters. Consequently, the motivation to "computerize" may be the hope that computers will solve all economic problems. The truth remains that not only have there been monumental successes, but there have been some colossal failures. This paper will attempt to outline a generalized guide to computer control and present methods for avoiding some of the major pitfalls. Since the investment required for computer control systems has been drastically reduced in the past year, small operations will likely find that computerized process control is attractive in areas where it has never been considered before, The discussion presented here is intentionally non-technical and directed towards those who may soon find they have a possible application for a control computer. The primary purpose of computer control is to reduce expenditure and increase profits by improving the quality of product, increasing the efficiency of operation, reducing the materials and man hours required or a combination of these. Success or failure to reach the desired goal depends, to a large degree, on a well-planned approach. This includes recognizing a possible computer application, properly defining the job which is to be accomplished, evaluating computer systems, selecting a capable manufacturer, and following through with sound systems engineering and programming.

Jan 1, 1965

Benchmarking of mining operations has been in vogue for a number of years: it seems teams are forever flying around the world to try to understand what other operations are doing. However, unless a benchmarking exercise involves data gathering at a fundamental level and a rigorous analysis process is applied, the trip will be nothing more than industrial tourism. When benchmarking is performed thoroughly, the range of comparisons that can be made is extensive and informative, and need not be restricted to sites with similar conditions and equipment fleets. This paper describes the detailed and rigorous process for benchmarking used throughout AMC benchmarking studies. The paper demonstrates how, through drilling down to the underlying drivers, the often heard cry of æyou canÆt compare us, weÆre differentÆ can be overcome. Included in the discussion are a number of significant issues that have been identified during AMC benchmarking studies. The paper then considers the types of opportunities that have been identified and the potential for improvement. The paper concludes with a discussion of the implications for planning, measuring and management of operational performance.

Jan 1, 2003

By C. E. BOCKUSD

WHEN Mr. Bain asked me to lunch with you he requested that I say a few words as to how the Institute could be helpful to the bituminous coal industry. I feel like saying, "Thank you, what have you?" I do not want to trace in detail the story that is old already to many of you. On the other hand it does take some little stage-setting to illustrate what is the matter in the bituminous coal industry, a trouble that must some day be cured. There has been something over a century of bituminous coal production as a real business in this country. True, Joliet and Marquette discovered coal in Illinois in 1673, according to published accounts of their travels, and shortly thereafter Father Hennepin also found Illinois coal in 1689. Coal was mined near Richmond in 1750, and Richmond shipped coal to New York and Philadelphia in 1789. But it was not until 1838 that the production of bituminous coal in this country totaled a yearly output equal to the minimum for one class A mine today, for that was the first year that production exceeded 200,000 tons.

Jan 1, 1930

By AIME AIME

HEREWITH is presented a preliminary report of a special committee, consisting of Erle V. Daveler, Paul D. Merica, and C. H. Mathewson (chairman), dealing with sundry matters of which many are of vital interest to all members of the American Institute of Mining and Metallurgical Engineers. As the report states, the initial purpose of the investigation was to determine ways and means to stimulate "the welfare and growth" of the Institute of Metals and Iron and Steel Divisions. However, it soon became apparent to the committee that most of the problems and possible correctives were of no less vital concern 1o members of the other Divisions and to the "unattached" group of members. Consequently, the Committee has authorized publication of the report and invites written comment from any member on the specific recommendations or on any other phase of the broad subject.

Jan 1, 1943

By L. B. Hales

Expert control of grinding and flotation plants has been successfully used in the minerals industry since the 1970?s. The earliest of these systems were written in a hard-coded fashion in FORTRAN, BASIC or Pascal. Second generation systems were built using the first experimental expert system shells that were being developed in the artificial intelligence community. Later systems were deployed in expert system shells designed for real-time processing plants that also included the ability to model the process with neural network models and optimize setpoint selection through the use of genetic algorithms. Significant performance increases have been achieved using these systems, but in general, they suffer from the static nature of their rules and to a degree the process models also. Typical improvements quoted in the literature suggest throughput rate increases of 4 to 8 percent and recovery increases of 1 to 4 percentage points. In over 30 years of designing and installing expert systems we have never seen performance numbers less that these but have often seen numbers in excess of the high values. However, once the system has been installed and tuned up the performance usually does not improve much thereafter. Granted, the initial increases in throughput rate and recovery are significant but a question always lingers, that is, can the expert strategies be modified further to squeeze a little more improvement out of the system. The answer to this question is a resounding yes, however a complete understanding of what we do well as designers and operators of expert control systems is required as well as how we can improve upon our best practices is required to move us from the performance plateau we have been on for a number of years to a new higher level of performance.

Jan 1, 2009

By R. G. Tarr

During an intense and accurate study of initiation systems used on an AngloGold mine, Mine A, poor drilling practices were revealed. Graphic results of all actual measurements taken are shown below. [ ] Accurate drilling of shot holes will determine whether a mining operation is payable or not and at what pay limit mining can take place. Losing 30 cm of a potential 120 cm-hole length will result in a number of consequences, i.e.: ?Higher stoping costs ?Drilling of one shot hole twice in every five shifts ?Increased explosive cost as a result ?Excess stress on hangingwall and footwall due to bad face shape ?Excessive blast damage before the area is worked out. No wonder we have such a high-risk operation. Drilling accuracy is crucial to the profitability on any mine as profits are directly related to the quality and utilization of the drilled shot holes.

Jan 1, 2000

By Emory J. Douglass

Mining companies are unique in that they extract mineral resources and must therefore deal with ecological disturbances and other special problems. Like most enterprises, however, their primary motive must be to make money. The problem of mining investment starts with the question of what "make money" means. This article proposes an answer consistent with what economists call the theory of the firm and then applies it to two of the common, and perhaps unrecognized, problems connected with min¬ing investment. In essence, the concepts presented here call for thinking to terms of the income change associated with a given change it outlays or operating procedures To illustrate. ABC Distributing Co. has just discovered the power of advertising. It has raised its annual advertising budget from $25,000 to $50,000, and sales have, zoomed from 250.000 to 350,000 units. The company buy, for 50e per unit and sells at $l. This move has produced $50,000 of operating income for $25.000 in additional advertising expense. This looks great, so the next year the advertising budget goes up to $100,000. Sales go to 440,000 units. With 90,000 more units at 50[c] per unit, ABC sales are up by $45.000. Its advertising costs, however, went up $50,000.

Jan 1, 1971

By Howard H. Fields

Any mining engineer with a desire to operate independently, with some financial backing, and with no fear of heavy responsibility and long hours, should be able to make a comfortable living in Mexico. Barring a few inconveniences such as a lack of satisfactory liability or accident insurance, the difficulty of obtaining repair parts or vehicles, and the length of time required to receive returns from shipments, the operation of small mine is not at all difficult. It is, in fact, a little easier to find a good prospect in Mexico than in the U.S.

Jan 1, 1950

By D J. Hill

"Mining companies routinely invest in improvements to their processing operations, but often these enhancements do not work to full effect.Improvements can be ineffectual because underlying process problems are not identified or prioritised for correction or repair.This is frequently because ‘black box’ solutions deployed to implement process control improvements typically rely on instrumentation to provide data for algorithms to work effectively, and these solutions are often ineffective or disabled at mineral processing sites.There are three key reasons they can fail to deliver: vital instrumentation is not calibrated or functioning as required basic process control and loop tuning was not implemented correctly or is in need of tuning there is an inability to support the ‘black box’ solutions on-site.Many of these problems can be overcome by implementing operational analytics that identify where problems are occurring and prioritise where improvements need to be made.Incorporating operational analytics into process improvement is not a new methodology. It is more a back-to-basics approach to make more efficient use of capital and systems already deployed.Data collection systems, such as the OSIsoft PI System, provide real-time and historical process information for process control experts to analyse and identify areas for improvement. However, most systems are not used effectively. With some simple enabling, data collection systems can provide evidence for prioritising investments in improvements and determining an investment’s effectiveness.MIPAC advocates that the initial step, with analytical evidence, is that clients review the control strategies and implement small influential instrument repairs/calibrations and operator training. This can significantly boost process productivity without the need to spend large sums of money on new capital or employing expensive, difficult to maintain ‘black box’ solutions.A simple Stage-Gate®-style approach ensures that small investments in evidence-based process improvements deliver significant benefits to mining operations.CITATION:Hill, D J, 2014. How to prioritise process improvements, in Proceedings 12th AusIMM Mill Operators’ Conference 2014, pp 307–314 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 1, 2014

By Takashi Nakamura

Dismantling and detachment of parts from e-scrap are essential and involve higher cost techniques in pretreatment processes for physical separation. New techniques are desired for effective recycling of minor rare metals, therefore, we are trying to develop new detachment processes such as a new break down process. The principal of this new process is an electrical disintegration by electric pulse. E-scrap is broken down by high voltage electric pulses in water. IC chips and LSI can be detached from printed circuit boards under proper conditions. Ta- capacitors are also broken down to plastic parts and Ta sinter with lead wire. This is very useful in terms of pretreatment for e-scrap recycling. Also in the case of metallurgical production, with its intrinsic potential of smelting, extraction, enrichment and separation methods, play an important role in the context of minor rare metals.

Jan 1, 2015

By Leonard Harris

Good morning ladies and gentlemen. I would like to thank Hans von Michaelis for inviting me here today to talk to you on the subject of "How to Reduce Capital and Operating Costs at Heap Leaching Projects". The comments I have to offer are based on my experiences in gold heap leaching by Newmont Gold Company in Nevada, by Newcrest in Western Australia (formerly Newmont Australia), by Minera Yanacocha in Peru, by Penmont in Mexico, by Z­Mont in Uzbekistan, by the Hochschild Group in Peru and expe­riences in copper heap leaching by Magma Copper Company in Arizona and as a consultant on several other smaller projects worldwide. These comments are a mixture of technology, ideology, philos­ophy, strategy, logic and opinions and might be looked at by many of you as "one man's view". I like to look at them as "a view from the bridge". Let me add that it doesn't bother me that you may not agree with my comments and that I would be interested in your comments or criticisms at the end of this presentation. I don't intend to discuss the details of the mineralogical and metallurgical test work. I will assume, for this talk, that the test work has been conducted very carefully and that the ore in ques­tion has been determined to be heap or dump leachable. Let's begin with a couple of don'ts! ! First, "don't build the mill until you have a mine". This might sound to many of you as fundamental but believe me it continues to happen. The minable reserves should be well known and established as being economical to mine and leach. NPVs, ROis and IRRs are fine if you can be sure of the gold price you use in your calculations. The best method is to carefully estimate the capital cost and, most importantly, the operating cost per ounce of gold recovered which should include the repayment of the borrowed capital and the interest thereon. For example, if the operating cost under these conditions is $200 per ounce, you have a project. If it is $400 per ounce, walk away f om it. Incidentally, the same prin­ciple can be applied to projects involving other metals such as silver, copper, lead, zinc, etc. The second don't is - "don't be sheep". Don't climb on the bandwagon with respect to design and operation because every­one else does it a certain way. Keep an open mind, be versatile, look for change, look for every possible innovation for reducing capital and operating costs. Beware of those who will tell you "we tried that it won't work" or "it's too expensive" or "that's a crazy idea" , <' ''what do you know about mining - you are a metallurgist aren't you" or "what do you know about metallurgy - you are a miner aren't you" or "only geologists can handle this issue". Be careful about pigeon-holing people according to their basic degree and experience. In these days of low metal prices, we need to consider everybody's ideas, as crazy as some of them might seem.

Jan 1, 1998

By D. Kelley

Due to pricing volatility and lack of availability of metals, the use of non-metallic materials of construction in metal extraction and refining processes has increased significantly in recent years Even though costs and availability of metals has improved recently, these factors are not expected to continue into the future as metal supplies once again fall short of global demand. One of the most common non-metallic materials of construction used in metal extraction and refining processes today is Fiberglass- Reinforced Plastic (FRP). These processes often require materials of construction that can resist acids and high concentrations of acid chloride salts. As shown in Table 1, FRP based on epoxy vinyl ester resin has the same chemical resistance to acid and better resistance to acid chloride salts than alloy C-276 and is superior to 2205 stainless steel in both cases.

Jan 1, 2010

By P J. Chapman

Recent catastrophic failures of tailings storage facilities (TSFs) continue to highlight the need for a detailed understanding of failure modes and the defences that are in place within the design to mitigate the failure modes. However, in many cases the instrumentation devices and monitoring approaches selected during operation do not link back to the design defences and inappropriate or redundant instrumentation is often installed. Candidate instruments and monitoring approaches (critical controls) are presented and matched to critical failure modes, with clear linkages to the intent of each instrument/monitoring approach. Commentary on where complementary measurements with independent technology types are recommended to provide greater assurance of trends to the design engineer or TSF owner is also presented. In response to the recent TSF failures, an increasing focus is being placed on instrumentation and monitoring relating to slope instability and safeguarding against the potential for static liquefaction, using a critical state soil mechanics framework. To support selection of appropriate zoning within a stability model, three complementary devices are recommended – vibrating wire piezometers to provide an indication of pore pressure and allow the phreatic surface to be inferred, tensiometers to confirm the presence of unsaturated conditions (and hence low potential for undrained failure) and moisture content sensors to provide an indication of void ratio, and hence state parameter, in saturated zones. The combination of VWPs and tensiometers will provide complementary measurements in the saturated and unsaturated zones, and also provide information on the extent of any near-saturated zones, provided that sufficient instruments are installed.

Jul 1, 2021

By d&apos, I. J. Agati

The stockpiling and reclaiming of bulk materials can be a challenging task for engineers seeking the optimum solution for plant needs, reliability, and at lowest unit cost. The objective of this paper will be to expose advantages, disadvantages and limitations of many storage and reclaiming systems to the responsible engineer and management. The paper will emphasize the practical aspect of stockpiling and reclaiming methods. Many valuable and interesting papers are available dealing with the theoretical viewpoint and application of a particular manufacturer&apos;s machine. Several of these are mentioned in the bibliography. As many practical parameters as possible will be given. After twenty years in the field of designing and selling bulk materials handling systems, the needs of the user and the plant are recognized and reasonably understood. This paper cannot give solutions to all problems In this vast field but will stress practical applications and examples of various installations. The evolution of advancements in materials handling is based upon not only technological innovations, but learning from many experiences of others and utilizing them as stepping stones to improved installations.

Jan 1, 1969

Determine what diameter piping is necessary to obtain sufficient water flow to spray nozzles used for dust suppression. Approach A simplified, diagrammatic method of calculating the flow of water through a proposed system consisting of a supply line and two banks of spray nuzzles is outlined. How It Works The pressure versus flowrate of the supply at the tapping point must be known or measured. The supply curve of typical city water at a 1 ¼ -inch pipe outlet is shown by the lowest curve in Figure 1. A supply curve for a typical pump fed from an open sump is shown by the middle curve. The combination of these, the supply curve of a pump fed by the city water supply is shown by adding the lower two curves to get the upper curve. A pump supply curve showing flowrate versus pressure is usually supplied by the manufacturer. The water supply line flow curve can be determined by measuring the time required to fill a 55 gallon barrel at various valve settings to determine flow, and by measuring corresponding pressures at the valve with a gauge.

Jan 1, 1979

By A. Ross Rornmel

ABILITY to speak effectively is one of man&apos;s most longed for and coveted abilities. It is the ability to stand on one&apos;s feet, transfer knowledge and thoughts to others, to reach an objective professionally or otherwise by leading groups through a channel of planned thought. Each day group speaking plays an important part in making or marring success, and the engineering profession often provides this opportunity and requirement. An ability to speak effectively develops courage, poise, confidence, and prestige for the speaker. The technical man cannot be reluctant to face an audience. He is often called upon to do this in presence of employees, supervisors, and other groups. His ability to speak effectively is as much a requirement as the fundamentals of his profession. The three fundamentals of effective speaking are: (1) Enthusiasm and Confidence. These are joined because of their close relation. (2) Preparation. This includes knowledge of the subject. (3) Presentation. By this is meant the features of delivery.

Jan 1, 1946

By Lysle E. Shaffer

TEACHING engineering students how to write and speak effectively -is one of the greatest problems facing the technical schools today. No phase of engineering education has received more criticism, and rightly so, for the criticism is justified. Year after year we continue to graduate men that are indifferent to the use of a tool they will need every day of their lives. Our young engineers cannot write a clear, concise report, and their business letters are a disgrace to the profession that takes pride in precision. The problem is not new. The remark ascribed to Sir James Barrie, that "The man of science appears to be the only man who has something to say, just now-and the only man who does not know how to say it" is as uncomfortably true today as it was thirty years ago. The records of meetings of engineering educators and the transactions of the engineering societies show that the inability of the engineer to communicate his ideas has been discussed for years. Engineering educators, prodded by industry, have recognized that the problem exists, but they have not solved it. Instead they continue to expose the student to composition and rhetoric, hustle him through English and American literature, and then blame his high school because he does not know enough English grammar to write a clear sentence. We must face the fact that the graduate is not going to reflect on the high school, but on his college. If the high school has shirked the job, the responsibility for correction rests on the faculty of the professional school.

Jan 1, 1948

By A. Tylczak, C. Norman, C. Shook, S. Loif

"There are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes or malfunctioning equipment early, which allows problems to be corrected promptly.Sacré-Davey Engineering in Vancouver has performed over 50 Energy Management studies for various industries including: mining, pulp and paper, oil and gas, etc. Energy Management programs can be used to identify energy reduction opportunities, assess project feasibility, complete equipment selection trade-offs, as well as to monitor and manage energy costs. Benefits of energy management programs are reduced energy costs, reduced maintenance, and increased plant automation. Additionally, energy management can provide access to utility incentive funding and quantify savings which can greatly improve the return on investment of potential projects.Energy management studies are funded by many Utility programs across Canada. There are various programs available for existing plants energy audits, project feasibility studies, new plant design reviews and energy monitoring and targeting, etc. There are capital incentives available which can significantly reduce payback period.This paper discusses how energy management can be used to support mill/mine operations groups, maintenance programs, as well as expansion or green field projects. This paper will also provide an overview of Canadian Utility companies programs and how they can assist mining companies.IntroductionThere are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes and identify malfunctioning equipment early, which allows problems to be corrected promptly."

Jan 1, 2015

By Ralph H. Phelps

WHAT information do you have on precision investment casting? Please send me all available information on the removal of paraffin from oil wells and pipe lines. How can I find out how to remove magnesium oxide from lime? I want a good book on the pickling of steel. Can liquid oxygen be used as an explosive in a mine? Where can I get a bibliography on the plasticity of metals? These questions, selected from the scores of questions asked the Engineering Societies Library staff every day, indicate some of the diversity of the requests received. The samples chosen relate to interests of AIME members but the questions that come to the Library by mail, telephone, telegraph, and in person cover all fields of engineering, science, and technology. Some questions can be answered quickly; others require extensive searching. Those that can be answered in a few minutes or ten, twenty, or even thirty minutes are usually done without charge. For the more difficult questions a charge is made. In this way those requiring considerable service pay for it and the Library finds it possible to serve more persons.

Jan 1, 1948

By George P. Tateosian

Merchants perform a number of functions in the copper market. As a major distribution arm of the copper industry, they secure scrap and other copper bearing materials for processing into usable refined shapes. These are ultimately sold to fabricators. Merchants &apos; hedging and arbitrage activities help keep values in proper relationship from product to product or region to region. Through these switching and trading operations, they optimize the flow of copper from mine to consumer. And finally, merchants act as a repository for copper units during times of surplus and a stockpile from which to draw during tines of shortage.

Jan 1, 1979