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By W. J. Cherones

This paper describes the history of the development and application of the electric mining shovel in open-pit mining, dea1ing particularly with far-reaching advancements in three primary areas: metallurgy, mechanical design and electrical systems. Hoist drives and crowd drives, including the Magnetorque and Electrotorque systems, and the integral propel drive are given close attention.

Jan 1, 1972

By W. G. Davenport

This chapter demonstrates how our matrices can be used for controlling a flash furnace. Specifically, it shows how we can determine the adjustments in industrial oxygen, air, oil and flux input rates that will; (a) correctly alter product temperatures and compositions to newly targeted values (b), maintain set-point product temperatures and compositions with varying feed compositions and feed rates. It also discusses corrective actions that might be taken when furnace temperature and matte grade unexpectedly change.

Jan 1, 2001

Good morning ladies and gentlemen of the AIME. I was doubly pleased when Toby Yu asked me to present to you my thoughts on the past, the present, and the future of bulk transportation by barge. My first pleasure comes from sharing with you the subject that has been my career for many years. I love this industry in the same way Mark Twain loved our rivers. Somehow, I can find in all of the activities that make up this crazy barge business the same sort of excitement that he found in "steam boating." The second reason for my enthusiasm is that Toby carefully pointed out that the presentation had to be kept to a maximum of 15 minutes. I can promise you that I will hold to his maximum time limit.

Jan 1, 1982

By AIME AIME

AT Williams College, in the quaint old New England town where people still go to the post office for their mail, an interesting institution has come into being as one of the aftermaths of the peace conference at Paris in 1919. The war taught the world many things about economics although much remains to be learned and more to be appreciated. B. M. Baruch, H. A. Garfield, president of Williams, and others who took part in the conference at Paris or in preparation for it, feeling that benefits would accrue from informal friendly discussion of the problems that lead to political differences between peoples, called together a summer conference in 1920. This has now become an annual affair and is coming to be looked upon as an important center for developing and stimulating public opinion. Membership in the Institute is by invitation and the lists change to correspond with the particular subjects taken up. Each year a number of distinguished foreign public men are invited to be the guests of the Institute and to meet men and women from various parts of the United States interested in their special subjects. Round tables, general conferences, and public lectures are the means employed to bring out discussion. The first are organized by groups, each including usually 25 to 40 people interested in a special subject and meeting three times a week for informal discussion. Teachers, writers, economists, engineers, business men, indeed men of all vocations and many shades of opinion, are brought together. Once a week each round table presents in general conference with the members of all other groups the more general conclusions reached in its own decisions. Afternoon and evening lectures are given by the foreign guests and these are open to the public. The lectures and the general conferences are reported widely in the press but the proceedings as a whole are not printed, no resolutions are passed, and no action is taken or contemplated. The whole plan is to furnish a forum for free discussion in hopes that the difficulties of various groups and peoples may be taken up sympathetically and good understanding promoted. There is no creed, doctrine or dogma to which the Institute is committed and widely different views are currently presented. The constant effort is to bring out points of view and the reasons for them rather than to build up convincing arguments favourable to a specific action

Jan 1, 1926

By S. H. Ash

IN no part of the world other than a small area in Pennsylvania is anthracite mining an industry of major magnitude. As the deposits of anthracite in the United States are limited virtually to Pennsylvania, the difficulties of this industry have been commonly considered a state rather than a national problem. However, there is also national interest in the conservation and wise utilization of all the country's fuel resources and in the control of interstate waterways. The anthracite industry is confronted with a serious problem of water accumulation in many of the mines, a problem that must be solved in the near future if progressively higher mining costs are to be avoided. It cannot be solved by the operating companies without state or Federal aid, or both, owing to the magnitude of the work required, the diversity of interests of the coal and surface ownerships, the hazard to the whole mining community, and interests affected outside the mining region. 'The costs of abating the ever-increasing surface seepage to mine workings and of handling this seepage once it has occurred are beyond the eco¬nomic resources of the operating managements.

Jan 1, 1941

By Andreas Bienz

The safety of persons from accidental explosions and fires during manufacture, storage, transport etc. of explosives, pyrotechnics, propellants, firework and ammunition is most commonly assessed according to prescriptive rule-based approach: Safety is given when all requirements which are listed in numerous regulations and directives (such as e.g. safety distances, limited quantities, protective installations etc.) are complied with. Such a deterministic prescriptive rule-based approach is quite easy to apply but has got disadvantages, however: The actual state of safety in a specific case is not explicitly and quantitatively expressed, and it is not distinguished between the endangered individuals and the whole group. As a result, the effects of the safety measures cannot be measured. This is why uneconomical and in the worst case useless safety precautions cannot be avoided. In addition, waivers are difficult to negotiate, meaningful and sound arguments for pro and con being lacking.

Jan 1, 2007

By P Standish

Qualitative risk assessment methods are not well suited to considering complex systems and potential interactions of new technology. As part of supporting tier one mining organisations and international industry groups, the author and colleagues have innovated processes to help provide better solutions to sites/companies considering a move to implementing proximity detection and collision avoidance systems. The process identifies required operating states for the system. By applying a combination of research and team-based analyses, a rigorous identification of credible failure modes which could cause these states to be lost, is identified. Finally, required business inputs, expressed in practical terms are distilled from regulator, industry, organisation and site in a way which clearly addresses the failure modes and so retain the required operating states. These business inputs identify improvements for site arrangements (EMESRT levels 1 to 7) before identifying functional requirements for technological collision avoidance solutions (levels 8 for advisory and 9 for autonomous). The paper presents a case study synthesised from multiple sites analyses and will provide guidance on where to find additional resources to assist in making the best possible transition to better equipment and road network solutions.

Jun 22, 2022

By C N. Hatton, K Ward

Tailings operations are inherently reactive as operations personnel continuously contend with a concentrator reject feed (tailings) transient in physical and engineering properties, which places a constant constraint on capital and operational spending. It requires a unique skill set to manage the prescribed distribution of tailings under unenviable conditions. Enter the tailings operator, an oftenundervalued commodity and untapped resource that can provide benefits beyond the rigors of dayto- day operational support. Experience consistently demonstrates that skilled and committed operators can serve a vital function in the safe construction of a tailings storage facility. It takes a village to raise a tailings dam. An important part of this process is establishing a culture of operational accountability and ownership. Operator development training is nothing new. However, we find that many of the intrinsic operator skills are left unexploited, and an operator's experiential knowledge base and creativity are commonly overlooked and underutilized. With proper training and guidance, these skills can be harnessed, contributing to safe dam operations. Operator engagement, when properly facilitated, provides tangible benefits ranging from improved tailings engineering properties to reduced closure costs. One important benefit is helping transitioning tailings management from reactive to proactive. There are many processes involved in the reactive to proactive transition process. One element of that process includes engaging operators in the tailings management process and facilitating legacy ownership. The core of operational legacy ownership is measured and described using five-stage operator engagement rubrics. Levels of operator engagement are presented with a description of the incremental benefits of each stage. An important part of legacy engagement is providing the tools to operators necessary for managing the tailings. Therefore, the approach identifies specific methods used by operations personnel to control tailings distribution and in-place properties. The end goal of leveraging operator engagement is to facilitate committed ownership and transition tailings management from an inefficient, reactive process to an improved, cost-effective, proactive practice.

Jul 1, 2021

By Guilherme L. M. G. Carvalho, Zachary T. Fleming

In a world of 2-dimensional design documents, envisioning and understanding 3-dimensional interferences for complex foundation construction scenarios can be challenging. Videos and computer models serve as 3-dimensional spatial aids but have drawbacks related to a fixed perspective. Augmented and virtual reality (AR/VR) provide new tools to communicate design challenges and improve construction planning. This paper provides a practical look at the basics of AR/VR systems and the tools available to the foundation design and construction industry by giving a high-level example of the technologies’ use in the design and delivery phases of a complex micropile installation project for the remediation of a dam foundation. Using these technologies, GEI was able to design and deliver a complex foundation remediation solution. AR/VR benefited regulators, and the client, to help understand the design concept, construction sequencing, and approach to overcoming installation challenges. Due to its user-friendly nature and less rigorous programming and hardware requirements, AR proved to be more useful than VR for this scenario. AR/VR will likely not replace videos and computer models; however, it can be a useful 3-dimensional visualization aid that complements the project delivery process and offers benefits that traditional methods cannot. INTRODUCTION Augmented and virtual reality is a promising and rapidly developing technology within the engineering and construction world. Like any rapidly developing new technology, the language describing it can be confusing and dynamic. To eliminate the confusion some definitions must be made. AR/ VR definitions The definitions of virtual reality (VR) and augmented reality (AR) for the purposes of this paper are as follows: VR is a computer-generated immersive environment that the user experiences within a digital 3- dimensional space (Satava, 1993)AR is a composite view created by superimposing digital objects into the user’s real-world view (Azuma, 1997). Often, VR is used in an office environment and allows the user to “visit” the digital site to review site planning, construction sequences, and interference geometry. AR can be utilized in both the office and onsite environments. Like VR, the in-office application for AR is commonly site planning. AR also can be utilized in the field for applications such as seeing through the ground to locate known existing obstructions like utilities, gas tanks, etc.

Jan 1, 2019

The ASC has a dual role of business facilitator and law enforcer. Only certain types of expert report are of interest to the ASC. The powers of the old Companies Code and the Corporations law are compared. NCSC Policy Release 149 was dependent on the prescriptive powers given to the NCSC in the Companies Code. The Corporations Law does not give the ASC power to prescribe the contents of expert reports. The requirement now is for all necessary information. Research evidence is that some investors want simpler prospectuses while others need more detail. The ASC's examination of expert reports is after registration of primary documents. This leads to a necessity for experts to maintain adequate records.

Jan 1, 1994

By Karl Gugel, Dante Garcia, Peter Czel, Eduardo Nunez, Joshua Morales, Boris Sullcahuaman

Real-time operational excellence is achieved through the seamless integration of various components. Key aspects include precise instrumentation, real-time data collection, data analytics, and an efficient optimization platform. Additionally, to ensure success, the real-time optimization platform must be incorporated into the site’s internal process control system (Nunez, 2022). This paper provides an overview of practical lessons and best practices for autogenous (AG), semi-autogenous (SAG), and ball mill (BM) grinding. It highlights the implementation of advanced instrumentation, specifically vibration sensors on the rotating mill shell. The paper also delves into the application of advanced analytics necessary for generating new measurements that accurately represent real-time grinding activity in the mill. These Advanced Analytics Measurements (AAM) are compared with well-known grinding curves to determine the optimal grinding point. The discussion focuses on key industry opportunities using real-time mill shell vibration results to derive new correlations and optimize the grinding process.

Feb 1, 2025

By S Dykes, R J. McCarthy, B Klein

There is growing interest in the mining industry on the application of ore sorting. While many are familiar with particle sorting, including the limitations that technology presents (e.g. throughput), bulk sorting, with its higher throughput potential, is less understood. Despite the potential to sort at higher throughputs, few operations have adopted bulk sorting processes, certainly not at large scale. It is suggested that the inability to reliably predict outcomes from bulk sorting may be limiting its adoption in mining projects. Consequently, an evaluation approach for bulk ore sorting has been developed such that mass pulls and grade upgrades can be predicted in the context of a mining study. The approach allows for evaluation of drill core assays and application of the consequently derived heterogeneity relationships to the block model for estimation of sorting outcomes. These processes were applied to conveyor-based bulk sorting for the CuMo project in Idaho, USA and are described in this paper.

Nov 10, 2020

By Morgan M. Sears

The LaModel program is widely used to calculate stresses and displacements on thin tabular deposits, particularly when multiple seams or complex mining geometry is encountered. The program itself allows the user to create multiple mining steps to show a progressive sequence of mining. However, LaModel considers each individual step as an independent steady-state condition, and any previous loading conditions of the materials are not tracked. It also does not consider any sort of dynamic stress change during the mining process. In certain circumstances, especially in multiple-seam situations, modeling a scenario of the seam of interest without considering the previous mining sequence in the off seams can potentially lead to inaccurate results. The primary objective of this paper is to present a situation where a potentially dynamic, unstable mining condition was encountered. It was not evident until the previous loading conditions in the off seams and the impact of dynamic stress changes in the active seam were considered. It is important to make the mining community aware of these potential modeling scenarios where the path-dependent nature of the mining sequence is of key importance. This paper presents a case history where room-and-pillar retreat mining was being conducted in a relatively deep cover stress regime where multiple seam interactions were present from both undermining and overmining. Mining in the active seam was being conducted with roomand- pillar mining techniques consisting of a series of parallel production panels being successively developed and retreat mined along a set of Mains. In this situation, the traditional global LaModel analysis without any path-dependent adjustments did not fully identify the area of poor conditions that were encountered. This paper explores the impacts of mining in the active seam on the lower seam which, in turn, has a negative impact on the active seam. This provided a solid foundation for the subsequent analysis of the three seams simultaneously. Based on the calibrated model, it is likely that retreat mining in the active seam resulted in increased stresses in the underlying seam that conceivably resulted in additional convergence and, most likely, additionally convergence of the pillars under the panel being developed. This in turn could have caused active subsid- The LaModel program is extremely useful for analyzing multiple-seam mining scenarios. As multiple-seam situations become even more prevalent, the potential for encountering a path-dependent mining scenario also increases. To successfully model path-dependent mining scenarios, the ground control engineer will be required to make sound judgments on the condition of pillars in sub-adjacent seams. These engineering judgments should be based not only on the current state of stress, but also on any prior or future states of stress. This means considering the stresses from over or undermining as well as stresses applied to the sub-adjacent seams from actively mining the seam of interest.

Jun 25, 2024

By Andrews Allen

WE all remember when, a few years ago the preparation of coal was nothing but a matter of having somebody at the face or somebody in the railroad car pick out the impurities; also the sizes were generally' made" over a bar screen. Anything that was black was coal; and the only matecia1 picked out was the slate or rock-impurities that could be distinguished by eye or by hefting. This was all right as long. & coal could be sold at. a good price. After all, we are all in business to -make the most money honestly out of a certain acreage of coal and a certain plant. For this purpose what is required is the greatest possible recovery of marketable coal and the highest market price.

Jan 1, 1929

By Christopher J. Bise

Introduction In August 1977, the federal Surface Mining Control and Reclamation Act was signed into law. It stated that: "The Congress finds and declares that because of the diversity in terrain . . . and other physical conditions in areas subject to mining operations, the primary governmental responsibility for developing. authorizing, issuing, and enforcing regulations for surface mining and reclamation operations subject to the Act should rest with the States." Section 516 of Title V (Control of the Environmental Impacts of Surface Coal Mining) of the Act deals with the surface effects of underground coal mining operations. "Each permit issued under any approved State or Federal program pursuant to this Act and relating to underground coal mining shall require the operator to adopt measures consistent with known technology in order to prevent subsidence. causing material damage, to the extent technologically and economically feasible, maximize mine stability, and maintain the value and reasonable foreseeable use of such surface lands, except in those instances where the mining technology used requires planned subsidence in a predictable and controlled manner: Provided, that nothing in this subsection shall be construed to prohibit the standard method of room and pillar mining." This section raises many questions. Precisely what is the "reasonably foreseeable" future as far as land use is concerned? And what is the "standard method of room and pillar mining"? The first part of the paragraph seems to rule out longwall mining, but isn't longwalling a "predictable" manner of "planned subsidence"? Does the Act take into account variations among mining methods in differing regions or coal seams? With these questions and the need to comply with the Act's provisions in mind, many states may turn to the Pennsylvania Bituminous Mine Subsidence Act of 1966- the only comprehensive subsidence act passed by any state-as a model for their own programs. Thus, it is very important to evaluate Pennsylvania's Act to see whether its basic assumptions can accommodate national application. This paper will note the Subsidence Act's provisions and guidelines, briefly analyze the current state-of-the-art in subsidence damage prevention and control, and list several recommendations for altering the Act's application guidelines for different mining areas.

Jan 1, 1982

By Mark Hollingworth

"There is general consensus that as the world continues to change at an ever-increasing pace, companies must continually adapt their operations in order to remain competitive. Those that change fast enough, survive; those that don’t, perish quickly. Today, we hear that it is not worth the time preparing corporate business plans as they are out-of-date before the ink is dry. Within the corporate environment of the 1990s, we must “think” strategically, be a “learning organization”, keep our costs low, focus on our core competencies, stay as flexible as possible and create value. So-called “sustainable competitive advantages” can be obsolete before a patent is issued — if its even worthwhile patenting the advancement. This is industry in the 1990s.Now, while all this radical change has been underway in the global industrial environment, what have Canada’s universities been doing to keep pace with the change affecting one of their major stakeholders? Have they adapted their products and services to suit the new market conditions? Have they built closer links to industry to try to understand how better to serve this important client? Do they welcome industry input as to how to redefine their mission, objectives, strategies or their course contents? Do their students graduate with skills ideally tailored for the global mining industry? In the era of communication, can they write high quality reports in English, never mind speak French or Spanish?In an effort to provide Canada’s engineering faculties with a “blueprint” for the future, the Canadian Academy of Engineering pre-pared a report entitled “Engineering Education in Canadian Universities”, published in August1993, which concluded with the following recommendations:"

Jan 1, 1996

By J. H. Adkins

The goal of the project reported in this paper was to make recommendations for changes in roof bolting procedures and bolter design that would reduce roof bolter accident rates. To that end the project identified the major hazards associated with each task a roof bolter operator per-forms, normalized task accident frequencies. by the time spent on each task, reviewed equipment design features and operating procedures related to the identified hazards and developed recommendations for equipment and procedural changes that would reduce, if not eliminate, the hazards. The research steps completed during the project were: a. A review of related literature and re-search including roof bolting time studies b. The collection and analysis of 1975 accident data pertaining to roof bolter activities c. The normalization of the accident frequency data on the basis of time/task data d. A review of roof bolting equipment e. The development of a field data collection instrument f. The selection of mines for bolter observations g. The collection of field data h. Data analysis and problem specification i. The development of recommendations for corrective measures

Jan 1, 1978

By A R. Penney

Safety management, both personal and that associated with catastrophic hazard, helps to define the success of mining companies. Personal safety management, often categorised by slips, trips and falls, has been widely addressed, with numerous approaches successfully adopted. Catastrophic hazard can lead to a single accident (eg ground collapse, underground fires etc) causing multiple fatalities. Catastrophic hazard management in mining is an emerging discipline, and as such there are various pitfalls to demonstrate its effectiveness and success; it is much more than simply meeting regulatory requirements. Various standards, guidelines, and leading practices are available for reporting key performance indicators. While measuring and reporting safety related key performance indicators (KPIs) such as Total Recordable Injury Frequency Rate (TRIFR), Lost Time Injury Frequency Rate (LTIFR), are important, they often lack detail, and give little insight into the effectiveness of catastrophic hazard management strategies and controls. Catastrophic hazards are low likelihood, high consequence events, and as such demand a different management approach. Companies cannot use the suite of personal safety metrics to help demonstrate management of catastrophic hazards. In-field verifications have revealed that senior management commitment to safety is often clear, well organised, and resourced. However, there are often some inconsistencies between what management promotes and plan, to what the operational teams understand and implement. Communication and clear understanding of expectations were the common themes identified to help empower supervisors to reinforce requirements of catastrophic hazard management. A lack of specific, measurable, and time-sensitive goals and objectives for the short- or medium-term, making it challenging to track progress was another key observation. Development of an integrated, multi-disciplinary auditing process executed by an experienced team of technical subject matter experts, provided an in-depth understanding of the requirements of catastrophic hazard management. Areas such as underground fire prevention, explosive storage, electrical safety, mobile vehicle interactions, ground control, inrush, and shafts and winders management have substantial overlap and intertwined processes, and similar strategies for emergency responses. Auditing of catastrophic hazards and safety management systems compliance is only the first step in safety assurance. Completing operational performance audits in technical areas and benchmarking the site verification of safety management documents and verifications forms a critical part to clearly demonstrate industry leading safety practices. No longer is it the external inspection or regular hazard management plan review requirements that dominate, but rather the culture of continual hazard identification, management, controls verification, underpinned by improvement and follow-up verifications of the corrective actions.

Mar 29, 2023

By Austin Gudmundsen

"The smoke nuisance, like many other undesirable and longstanding features in our present civilization, is still with us. On reviewing the situation we are astonished to find no authentic record of a major smoke-abatement campaign that has succeeded in eliminating a smoke nuisance, in spite of the fact that the problem has been with us since the use of bituminous coal began. We might well ask ourselves where the trouble lies; is the problem impossible of solution? We can not blame the average citizen for harboring this thought as a conviction. He has been urged for so long but sees so little evidence of progress. He has repeatedly been assured by the scientist and the engineer in most convincing terms that smoke. is unnecessary, that it can be avoided; small wonder is it that he is beginning to distrust so-called authority on the subject.On the other hand, the scientist and engineer are entirely within their rights. We all know that even high-volatile coal can be and is now being burned with no visible smoke. We know that even small domestic heating furnaces, with favorable conditions and with proper care, can be fired by hand without producing much smoke. And we know that when such equipment is fitted with suitable stoking devices, little or no smoke results. What, then, is the answer?Perhaps we may learn something from a critical examination of a typical smoke-abatement problem. Probably one of the most enlightening campaigns that has been waged in the United States is that of Salt Lake City, Utah; therefore, the purpose of this paper is to discuss the important aspects of this particular case."

Apr 1, 1930

By LIONEL E. BOOTH

ORE tests are made for the purpose of determining the correct methods of treatment for any particular ore. They should be conducted so as to insure that the results obtained in actual mill practice, on ore of similar grade and physical nature, will duplicate the results obtained in the test work. As the expenditure of many thousand of dollars may be involved in the building of the necessary mill, the testing of ores calls for extreme care and skill in handling laboratory machines, and a knowledge of actual practice to guard against the danger of obtaining results in test work that would be impractical to duplicate on a commercial scale. The importance of a correct sample of the ore is at once apparent. No matter with what degree of care the test 4rk is done, it loses its value when made on an unrepresentative sample. It is the first safeguard against future disappointments in the loss of capital and time. A number of failures in the past have been traced directly to faulty or lax methods in obtaining the ore sample.

Jan 1, 1924