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By M. Javier

"Mining makes civilization possible. It also creates socio-environmental liabilities forcing us to ask how much more of this mining can our planet support. It is clear that the future of mining differs from mining in the future. The laws of nature are being compromised by mining. This paper studies the problems at the core of the mining business which need to be addressed. What kind of mining will serve our existence with nature on this planet? What kind of mining perspectives are we able to formulate without having negative effects for future generations? Is mining technologically sustainable? The values of predictions, imagination, and creativity must be integrated to define what mining should be. Those values should be in the technologies necessary to restoring equilibrium of nature (Geomimic) as well as in complete extraction of metals, better utilization of the mineral reserves, and design the usage of metals to recycle. The purpose of this research is to examine many views and perspectives for future generations and to accelerate the pace of innovation of having mining without socio-environmental liabilities by design and by understanding nature. KEYWORDS: Geomimic, Sustainability, Waste mine Design, Management by Loss. INTRODUCTION The future of mining is being stifled by many antiquated and stagnant attitudes and policies by the industry and society as a whole. The time is now or never for real action and education against these attitudes and to upgrade them to meet the current needs of this planet if we are to survive. Doing this will prove that we understand and respect nature for us and our posterity. It will also show a positive assessment that the mining process can be reversed before the point of no return. And that is to say, only if reversibility is still an option. It may not be anymore but it’s worth a try. We need to use our imagination and engineering know-how to come up with new proposals to change the core of mining. It would entail re-engineering. There is a profound difference between the future of mining and mining in the future. The future of mining is the continuation and persistence of past practices in the industry and expecting new results. Mining in the future requires a paradigm shift for extraction through modern thinking about mining as it pertains nature. The new paradigm for mining in the future would restore equilibrium with nature. Always keep in mind the connection of mining to nature. What is the future of nature? To predict mining in the future we need to use past experiences in mining and our knowledge of modern science and engineering to formulate a prototype that will enhance mining while maintaining equilibrium with nature. Mining and protecting nature are not mutually exclusive. This new prototype has nothing to do with the level of bonding or insurance that the mining industry can legally provide. The goal of this paper is to contribute some new ideas to help transform the mining industry based on the laws of nature and its limitations. Using this new prototype we will develop the following 1. Extraction of minerals Reserves-Dimensions-Technologies 2. Usage of mineral resources-Manufacture’s products designed to be reused and recycled 3. Nature- Equilibrium (physical, chemical and biological)"

Jan 1, 2016

By Craig M. Sams

Dry grinding circuits and factors influencing the selection of the most appropriate grinding system for a given ore selection are discussed. Comparisons of the drying, grindability, installed costs and operating costs are presented for several grinding systems.

Jan 1, 1994

By J. J. Poveromo

"Iron ore for alternate iron processes concerns alternate iron products designed for use in EAF (electric arc furnace) steelmaking processes. These alternate iron products include both DRI (direct reduced iron), HBI (hot briquetted iron) and merchant pig iron. Merchant pig iron can be produced in conventional blast furnaces, mini blast furnaces (including charcoal BF's) or novel processes such as RHF/SAF (rotary hearth furnace/submerged arc furnace) such as Iron Dynamics or RHF such as Mesabi Nugget. These novel processes are coal based and can use iron ore concentrates or recycled steel plant oxides. The blast furnace processes can use conventional feed materials: pellets, sinter, lump ore and coke. However, DRI and HBI processes are predominantly pellet based but require DR grade pellets that are low enough in acidic gangue (SiO2 and Al2O3) to avoid additional expense in the EAF process This paper will focus on the quality and availability of DR grade pellets for NAFTA DRI/HBI plants but also concentrates for fines based processes and feed materials for merchant pig iron production. INTRODUCTION This paper will outline alternative (to the blast furnace) competitive ironmaking processes and process routes. Within each section the types of iron ore to be utilized will be discussed. Before discussing some of the details of these processes, it may be appropriate to review some definitions and commonly used terms within this industry. DefinitionsDirect Reduction: Reduce iron oxide to metallic iron without melting. Unreduced ore compounds remain as undesirable oxides • Direct Reduced Iron: Iron oxide feedstock exits in same form as entered (pellets in, pellets out; lumps in, lumps out) • Hot Briquetted Iron: DRI that has been hot (1200°F, 650°C) briquetted to a high density pillow shaped briquette • Hot Metal: Molten iron in liquid form, above 2500°F, 1370°C • Pig Iron: Solid product of the iron blast furnace • Residuals: Undesirable elements such as copper, nickel, chromium, tin, sulfur, molybdenum and phosphorus • Gangue: Rock minerals in the iron ore such as silica (SiO2), alumina (A2O3), calcia (CaO), magnesia (MgO). These remain in the oxide form in DR processes. • Reduction: Fe2O3 + 3 CO = 2 Fe + 3CO2 2 Fe2O3 + 3 H2 = 2 Fe + 3H2O (Fe2O3 > Fe3O4 > FeO > Fe)"

Jan 1, 2018

By LUIS ALBERTO TORRES-CRUZ

The Plewes method is relatively well known among geotechnical engineers interested in assessing the liquefaction potential of soil deposits. Furthermore, it was one of the four methods considered in the post-failure investigation report of the Feijao Dam I, also known as the Brumadinho Dam, in Brazil. The inclusion of the method in that report is likely to increase its visibility among geotechnical practitioners tasked with assessing the liquefaction potential of tailings. While the authors of the method duly presented it as a screening method, more recent technical literature contains conflicting views on its reliability. Considering the popularity of the method and that the safety record of tailings dams is a cause of great concern, this study assessed the uncertainty of results from the Plewes method. The study concludes that, even under optimistic assumptions, the results of the method are too uncertain for detailed characterization of tailings deposits.

By Eivind Grøv

"INTRODUCTION Tunneling and underground excavation is related to handling of uncertainties, risks associated with geological conditions are significant and ‘unexpected geological conditions’ often claimed. This fact was brought to the table long ago, and ITA (the International Tunnelling and Underground Space Association) published its 25 Recommendations on Contractual Sharing of Risks in 1988 (Ref. 1). This public-cation constitutes an important asset to the tunneling industry in terms of being a guideline for those working with contractual issues, even today almost 30 years after being published. A more recent document is the ITIG code of practice for risk management of tunnel works from 2015 (Ref. 9). Various countries or geographical regions have their own view and tradition on risk sharing and tunnel contracts. In Scandinavia unit rates contracts are most commonly used with bid-build model, it shares risk between owner and contractor, owner retains the risk for geological conditions while contractor carries risk for performance efficiency. Rock strengthening is determined assessing rock mass quality encountered at tunnel face. Grouting is applied to stem water. Actual quantities may differ from the contract’s BoQ but a flexible contract with remuneration is installed to enable adjustment of actual quantities. Variations of quantities involve a clause to adjust construction time. Unit price contracts deals with expected and foreseen still ‘unexpected geological conditions’, if the ‘unexpected’ element results in variations in quantities. Work activities have quantities and ‘standard capacities’ for regulation of construction time. Variations in quantities are expected in tunnelling and hardly deserve the term ‘unexpected’. If truly unforeseen geological features necessitate work not included in the BoQ, then the contract must be supplemented and can be said to be inappropriate. Fixed price contracts may not provide the intended predictable cost and is as such also inappropriate in the view of a risk sharing principle, once the geological baseline proves to be incorrect. ‘Adjustable fixed price’ contracts, combining unit rate and fixed price, may prove suitable."

Jan 1, 2016

By M. E. Gershon

Software for coal blending has gained a lot of recent attention as micro-computer programs have come on the market. Some of this software is appropriate and some is not. This paper looks at the types of models being used and points out the strengths and weaknesses of each. Recommendations are then made concerning the level of detail required for these programs, relating this concern to the various ways in which coal companies are using these programs. A checklist of company requirements for these programs and available pro-gram-features provides an aid in matching the program to the company.

Jan 1, 1988

By J. S. Walstrom

Debate on an appropriate, acceptable method of regulating mine and mineral processing wastes has been ongoing since Congress passed the Resource Conservation and Recovery Act (RCRA) on October 21. 1976. Final regulatory determination on which mineral processing wastes are excluded from the RCRA hazardous waste regulations under the Bevill amendment was made by the U.S. Environmental Protection Agency on June 13, 1991. Regardless of whether a mining or mineral processing facility?s waste stream(s) lost or maintained its exclusion status under the Bevill amendment, that facility can expect more stringent regulation of affected waste streams. These more stringent regulations will be added to an already complex regulatory maze, which includes the Clean Air Act (CAA), Clean Water Act (CWA), Safe Drinking Water Act (SDWA), Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), Superfund Amendments and Reauthorization Act (SARA), and Toxic Substances Control Act (TSCA), as well as state and municipal environmental regulations.

Jan 1, 1992

By R. L. Atwood

This paper discusses the metallurgical and Manufacturing input to Merrill-Crowe plants. Topics treated are pregnant solution chemistry, clarification, degassing, zinc addition, product filtration, accounting, and costs.

Jan 1, 1985

By T. K. McMahon

Formally, a mathematical model could be defined as: A set of equations whose solution will approximate the response of a physical process or system to a set of stimuli which appear as parameters in the equations. The purpose of a mathematical model is to permit the rationalization of experience to proceed by simulation rather than by physical experimentation. In the application of digital computer control to an industrial process, the mathematical model of the process (subsequently called the process model) is needed to calculate the present process performance from the measured variables and to predict the response of the process to a control change. Functionally, the cardinal element in process model development is a concise set of control objectives. These, besides implicitly defining the boundaries of the system to be modeled, will determine the accuracy demanded of the model its nature: dynamic or steady-state, and so forth, The objectives should explicitly define what process efficiencies, production rates, qualities are to lie within the scope of the computer control project, thereby providing a basis for simplifying assumptions in the development of the model. This requirement, a limited set of control objectives, is so often disregarded in formulating industrial control problems that its repetition can scarcely be avoided.

Jan 1, 1965

By William K. Brown

Are the results of an exploration program worth the cost? This is a question I suspect many of you are familiar with and, theoretically at least, it is an easy question to answer. The answer, of course, lies in comparing the future earnings stream the program is expected to generate, to the present value of the cost of carrying it out. While historical costs can be determined without much difficulty, estimating the value of a future earnings stream involves all sorts of assumptions regarding future costs, metal prices, inflation rates and an appropriate discount factor; and in the context in which the question arises, requires additional assumptions about mineral deposits which have yet to be discovered. As a practical matter, this kind of approach isn't likely to produce a very convincing answer; certainly not one convincing enough to satisfy a skeptical audience; nor one likely to temper the illusions of recent converts to mineral exploration, who are convinced that if enough money is spent, profitable discoveries will inevitably follow. Within broad limits, however, I believe it is possible to analyze the costs and results of gold exploration in the U.S.A. over the past 20 odd years in a useful manner. And while such an analysis is imperfect, it will provide some insight into this fascinating subject.

Jan 1, 1983

By Henryk Bystron

The underground fire areas are formed as a result of failure of an active fire extinguishing in mines. Such areas bring about a fire hazard for the work safety and for the mining operations. For liquidation of fire areas it is necessary to create conditions under which a possibly small amount of air is flowing to the fire. To achieve this end, isolation methods are used which consist in erection of full stoppings of various types, sealing practically the fire areas. These methods usually fail in oases when the coal seam is thick and the fire area is situated between the intake shaft and the outtake shaft in which a high-pressure fan is in operation. In such oases ventilation methods based on the balance of aerodynamic potentials in fire areas are to be used. For a very long time the isolation and ventilation methods have been developed in the world mining, No sooner than since 1980 the aerodynamic potential has been used in ventilation methods [1,2,6]. So far, the aerodynamic potential was called in different ways and was determined by different formulae which gave its numerical values more or less approximative. Nevertheless, even in situations featuring by a lack of sufficient theoretical bases of the aerodynamic potential the ventilation methods brought considerable profits in the field of safety in mines and of economics in mine ventilation [1-6,9,10]. The increase in the depth of underground mines and their equipment with expensive machines (apparatus) brought about that the Central Mining Institute at Katowice undertook research works which are crowned by the theory of the aerodynamic potential in mine ventilation networks [7]. The use of this theory in the mentioned ventilation methods will increase their effectiveness. Since the theory will be published in the III rd quarter of this year, we cite in the present paper the formulae and relations associated with this theory which are indispensable to present the balance of aerodynamic potentials in the fire areas in their control by ventilation methods.

Jan 1, 1980

By Salvatore] [Parand

Deep well disposal is a much used and abused term which is the panacea for wastewater disposal in some minds and creates near hysteria in others. It can be the answer to a difficult waste disposal problem, or if improperly employed, can create more problems than it solves. My purpose in this presentation is to focus on the value and limitations of deep well disposal as expressed by New York State's experience and policies. To he sure, I feel a place for such practices docs exist if adequate safeguards are utilized. I shall give a broad brush approach to New York's legislative, geologic and operational concerns and speak briefly on some case histories. I shall not delve deeply into the technological details since I am not an expert in mining exploration or well drilling.

Jan 1, 1973

At the 25th Peruvian Mining Convention, the start-up of Antamina was called ?the mining event of the year.? Antamina, one of the largestcopper-zinc mines in the world, began operations in May 2001.Augusto Baertl is Executive Chairman of Compañía Minera Antamina, the operating company. He said in a convention address that Antamina would be in full production in 2002. ?I would like to stress that Antamina is, in every respect, a highly stringent operation, as it intends to be the Peruvianmine of the future,? Baertl said. ?Antamina has set the target of being, and remaining throughout time, a model mine as to technology, environmental practices and social responsibility.? [ ] In the areas of technology and operations, Baertl noted that ?we have incorporated the best engineering design available and state-of-the art technology for mining, grinding and transportation processes, among others.? In the environmental area, he said that ?we have carried out careful environ-mental impact studies and have incorporated modern technologies and methods to control and minimize any environmental impact.? In the social field, Baertl noted that ?our relationship with neighboring communities is being developed under the premises of the social responsibility philosophy.? These include popular consultation processes, environmental committees and conciliation discussion committees. The purpose, he said, is to encourage communities located within the area of influence of the project to find and lead by themselves their path toward sustainable development, beyond the life of the operation itself.?

Jan 1, 2001

By K. Morsy, S. S. Peng

A new method of pillar stability evaluation was proposed. The unique feature about the method is that it estimates two types of stability factors for the pillar. The first stability factor is to measure how much the applied stress at that point is smaller than its strength, and the second stability factor is to predict whether or not the pillar will fail violently. The strain-softening behavior of coal pillars was simulated by the Drucker-Prager yield criterion. A new algorithm that simulates the strain-hardening behavior of the gob was used. A numerical technique to estimate the local mine stiffness (LMS) was introduced and verified by both numerical and analytical methods. A case of massive pillar failure in a room-and-pillar mine was used to define the stability limits for the proposed method.

Jan 1, 2003

By W. Bassow

In June 1972, when the United Nations convened its historic Conference on the Human Environment, only 24 countries had established government agencies with environmental responsibilities. Of these, 11 were in the industrialized world, 13 in the Third World. By 1985, the number had dramatically surged to a world-wide total of 145, with the greatest growth among the developing countries to 110, an increase of almost 1000%.

Jan 1, 1988

By William J. Kohan

Milling has traditionally been considered more art than science. In the last 10 years, significant improvements in process equipment have been made and we are finally taking significant steps toward approaching grinding as a science. Two machines have been at the center of this development. These are the roll press and the high efficiency separator. The former can be considered as a new technology or adaptation of existing i.e. roller mill. The latter is clearly an improvement of existing technology. Other machines have been introduced to a lesser degree and later. Among these are the CKP and Horomill. The purpose of this paper is to provide an over- view of the currently available modifications for operating systems and options for new milling circuits with some comments on their application and history.

Jan 1, 1997

By Marvin A. Ph. D. Friedman

The following paper describes an overview of evaluations for assessing the potential hazards associated with handling newly developed reagents used in the mining industry. Important factors in determining the risk and hazard associated with handling a particular chemical include hazard identification, dose-response assessment, exposure assessment, and risk characterization. The hazard evaluation step involves collecting and evaluating appropriate toxicology information on a chemical. This can include a comparison of the structure of a developmental chemical with that of a material with known toxicology information. Acute toxicology data, including oral, inhalation, and dermal LD50 values, eye and skin irritation data and sensitization or allergic potential information are typically generated for new chemicals. Environmental and in-vitro genetic toxicology data (e.g. Ames test) are also used to evaluate new mining reagents.

Jan 1, 1994

By R. M. Hays

Jan 1, 1980

By Alan D. Hoagland

The Flat Gap Mine is on Copper Ridge in the Appalachian Valley of East Tennessee, Large zinc orebodies occupy zones of solution and collapse breccias in lower Ordovician Kingsport limestone and dolomite, The principal ore mineral is sphalerite and the principal gangue is dolomite, The orebearing horizons are considerably more than 95% covered by thick residual clay, and geochemical prospecting under these conditions is an effective exploration technique which played an important role in the discovery and exploration of the Flat Gap Mine, The residual nature of the over-burden at Flat Gap is emphasized, Background heavy metals (mainly zinc) range from 50 to 200 ppm, and the anomalies range to 3000 ppm and more, About 80% to 9W0 of the soil zinc is in relatively insoluble form in solid solution with the hydrous iron oxides and in the crystal lattice of the clay minerals. Quite discrete zones in the soil with sharply contrasting metal value boundaries mark vestiges of bedrock mineralization, and such anomalous soil areas are often contiguous with partially weathered ore. It has not been possible on the basis of chemical criteria to distinguish between an anomaly formed from non-commercial mineralization and one formed from ore.

Jan 1, 1962

By A. T. Yu

The broken hill proprietary company Ltd., Australia's only steel producer, has come a long way. Since 1885 to reach today's. Capacity of 6.6 million long tons of ingot steel per year.* its Newcastle steel complex in New South Wales, located 100 miles north of Sydney and on-stream since 1915, has likewise shown continued impressive growth (fig. 1). The most recent expansion plans at Newcastle call for sub¬stantially increasing its production, with the help of some added facilities, but principally relying on the increase in efficiency of the furnace operation. Its modern raw materials blending system will playa major role in meeting Newcastle's new targets.

Jan 1, 1969