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By Milka Madahana, John Ekoru

For efficient management of operations, mining companies are required to be able to predict potential scenarios for main market factors. Competitive advantage and value creation are established through managing the value chain well. The mining value chain is usually faced with challenges from various shifts in commodity markets as well as ongoing uncertainties. Therefore, there is a need for accurate analysis of data from the markets, for the prediction of commodities, for instance, Precious Group Metals (PGM). The main objective of this research work is to apply machine learning methodologies with the aim to identify patterns and trends in the Precious Group Metals, and thereafter analyze and predict the future trends of these markets. Numerous machine learning models are applied to a dataset consisting of 15 years of daily price for eight precious metals namely Platinum, Palladium, Rhodium, Ruthenium, Osmium, Indium, Silver, and Gold. The results reveal the patterns and trends within the data sets and that different machine learning methods could be suited for the prediction of market prices for each of the PGMs. The application of an amalgamation of various machine learning methods may result in more accurate predictions of the PGM markets. Accurate prediction of market prices for PGMs will possibly result in unlocking untapped sources of value in the mining industry.

Jun 25, 2023

By T. Yue, Z. Gao, X. Tong, R. Liu

"Lead ions (lead nitrate) were introduced to modify the surface properties of scheelite, effectively and selectively improving the flotability of scheelite, with benzohydroxamic acid (BHA) serving as the collector. A series of experiments about the mode of addition and the ratio of lead ion to BHA were conducted and indicated Pb-BHA complexes were the active species responsible for the flotation. And two adsorption models of BHA on the surface of scheelite were established. For both the two adding methods, some kind of complexes formed by lead ions and BHA played a key role in the flotation process. Zeta potential, FTIR, and XPS studies indicated that the adsorption amount and intensity of BHA on the surface of scheetlie were larger by adding the reagents as a mixture. The mixed addition is conducive to form Pb-BHA complexes and improve the adsorption efficiency of BHA on the surface of scheelite, as well as the recovery of scheelite. INTRODUCTION Scheelite, as an important tungsten-bearing mineral, is nowadays utilized mainly by flotation (YIN and WANG, 2014; Sun et al., 2011; Gao et al., 2015; Gao et al., 2015). Flotation separation of scheelite from calcium minerals creates difficulties because of the existence of the same cation in the minerals and similar physico-chemical characteristics such as solubility, hardness, specific gravity, point of zero charge (PZC), etc. (Arnold and Warren, 1974; Deng et al., 2016; Deng et al., 2015; Ozcan and Bulutcu, 1993a; Yongxin and Changgen, 1983). The conventional collectors used in the flotation of scheelite ores are generally fatty acids or fatty acid derivatives (Bo et al., 2015; Oliveira and Sampaio, 1988; Shi et al., 2014; Sivamohan, 1988; Yongxin and Changgen, 1983). It is difficult to separate scheelite, especially from calcite, with these reagents because the adsorption mechanism of these collectors occurs through chemisorption of the oleate ion onto the mineral surface (Atademir et al., 1979; Changgen and Yongxin, 1983; Hiçyìlmaz et al., 1993; Hu et al., 2011). Therefore, it is almost impossible to separate them by fatty acid flotation without using any selective depressant. Although oleoyl sarcosine was used as a selective collector in the flotation of fluorite and siliceous scheelite ores (Ozcan and Bulutcu, 1993b; Ozcan et al., 1994), this selectivity is inadequate for a low-grade calcitic scheelite ore. Unfortunately, reagents such as organic colloids (dextrine, starch), quebracho, sodium phosphates, sodium silicate solutions containing polyvalent cations (hydrosols), etc. (Bo et al., 2015; Schubert et al., 1990; Shi et al., 2014; Yongxin and Changgen, 1983), used for calcite depression also depress scheelite to a large extent. Cationic collectors, such as amine and quarternary ammonium (Yang et al., 2015) and collector mixture (Gao et al., 2015) have been used to improve the scheelite flotation. However they have not been applied in industry due to the poor separation from silicate minerals."

Jan 1, 2017

By Gregory A. Vaka

Robins Engineers & Constructors, Inc. as the exclusive U.S. licensee introduced the PIPE CONVEYOR to the North American marketplace early in 1984. The sale of the first PIPE CONVEYOR in 1985 was a difficult task since the conventional troughed belt conveyor was the accepted and the most widely used means of continuous transportation of bulk materials handling in the world. Initially our clients viewed the PIPE CONVEYOR as a departure from the normal and accepted form of material handling. Since then, the parent company of Robins Engineers merged with Krupp of Germany to form KRUPP ROBINS, INC. in the United States. To date there are over 462 PIPE CONVEYORS operating worldwide with the majority of the long overland systems designed and installed by Krupp Robins, Inc. The PIPE CONVEYOR is now becoming the norm, viewed by those who are familiar with its capabilities as the preferred method of transportation for all bulk solids.

Jan 1, 1997

By S. J. Schatzel, K. M. Ajayi, E. N. Rubinstein, Z. Khademian

This study simulates the impact of a shale gas well casing breach near a longwall mine. Field studies are conducted to measure mining-induced permeability changes over the abutment pillar of a longwall mine, and a geomechanical model is developed in 3DEC, a three-dimensional numerical modeling code, to predict the aperture of fractures in the overburden at the study site. The predicted aperture values are used to determine mining-induced permeabilities, and the results are compared with the field measurements. These aperture values are provided as inputs into fracture flow code (FFC), which generates a stochastic discrete fracture network (DFN) model for the study site and predicts the potential shale gas flow to the mine. Results from 100 DFN realizations are statistically analyzed using the bootstrapping method to compensate for notable variation in fracture geometry. The results show a significant difference between the gas inflow for nearby panels due to increase in the induced permeability during mining of the second panel. The average gas flow to the mine was calculated as 4.72 × 10 m3/s (49 cfm) for a hypothetical breach at the Sewickley horizon during the first panel mining, 8.97 × 10 m3/s (19 cfm) for a hypothetical breach at the Uniontown horizon during the first panel mining, 2.16 × 10 m3/s (458 cfm) for a hypothetical breach at the Sewickley horizon during the second panel mining, and 8.07 × 10 m3/s (171 cfm) for a hypothetical breach at the Uniontown horizon during the second panel mining. Depending on the mine ventilation system, this could result in methane concentrations exceeding regulatory limits. Hence, these findings provide insights into the potential risk of an unconventional gas well casing breach near a longwall mine under shallow cover.

Feb 1, 2024

By R. Merkl

Since the 1940s, decanter centrifuges have become more important for increasingly complex solid-liquid or solid-liquid-liquid separation processes. Sometimes processed industrial or metalliferous minerals are abrasive or are treated with corrosive chemical agents. Traditional mining applications include the processing of coal, gravel and other products, where low-speed decanters, as well as screen bowl decanters and filters, dominate. These have been increasingly replaced by high-speed decanters during the last decade. Decanter centrifuges also started to play a key role in applications such as drilling muds, processing carbonates and separating SX crud in copper platinum ore concentrations of nickel and gold. Communication between machine producers and mineral processing engineers is vital for the right choice of materials and the design of the right decanter centrifuge for the individual process.

Feb 1, 2012

By D. J. Miller

Environmental considerations are extremely important in planning and carrying out mergers, acquisitions and real estate transfers. It is not inconceivable that potential or actual environmental liabilities could exceed the targeted company's net worth or the book value of the real estate of interest. It is therefore essential that an environmental due diligence investigation (DDI) be performed to quantify environmental liabilities before sales, mergers or acquisitions. This paper will discuss general procedures used in environmental due diligence investigations. The emphasis will be placed on mergers and acquisitions. It should be pointed out that the procedures discussed in this paper are general and must be modified to fit each particular merger or acquisition under consideration.

Jan 1, 1988

By B. D. Hansen

Newmont has been on a focused path of improving operations for many years. After the merger of Newmont and Santa Fe Pacific Gold, Newmont created significant synergies of over $50million per year in Nevada, primarily through optimal ore movements and consolidation of various functions. During the current period of low gold and copper prices, Newmont has refocused its efforts on efficient operations worldwide. This paper will describe the methods and programs that continue to be implemented at Newmont's many mine facilities in Nevada. Newmont has used a combination of computer technology, optimal use of infrastructures, procurement strategies, functional consolidation, enhanced mine planning and a variety of available metallurgical processing options to decrease the cost of operations and increase profitability.

Jan 1, 1999

By Robin J. Hickson

El Abra has mining concessions granting the right to exploit minerals in more than 130 km2 (32,122 acres). SCM El Abra owns “rights to occupy” the surface of these claims. The company also owns the surface rights over the process plant area and over land conveyor route. The project has procured all material easements relating to the mine area, processing facilities and access rights of way. Engineering, procurement and construction Figure 1 sets out the development and construction schedule for the project. Development is already well under way. As of early January 1996, about 70% of the project was complete and more than 80% of the capital expenditures were committed.

Jan 1, 1996

By Fei Chen, Xun Xu, Dezhong Kong, Yu Xiong

We address the problem of rib spalling caused by mining-induced roof movement. This problem affects production and safety of the working face. We address this problem by using the 3DEC numerical software to simulate the distribution and evolution regularity of displacement, stress, and the extent of plastic zone in the overlying strata and coal face during the advancing excavation of the 10,905 working face of the mine. Results showed that the first weighting interval of the 10,905 working face is 50 m, and the periodic weighting interval is 20 m. The fractures of overlying strata develop during the first weighting; the vertical stress and vertical displacement of the main roof increase by 45% and 10%, respectively; the vertical stress of the coal face increases by 11%; and the plastic zone in front of the working face increases rapidly. The displacement and stress of the main roof and coal face change periodically during the period of periodic weighting. The variation range during the periodic weighting is less than 30%, but the overall degree is larger than that before the first weighting. Finally, the integrity and rationality of numerical simulation are supplemented and verified by similarity simulation. On this basis, the proposed roof and coal face stability control scheme reduces the maximum horizontal displacement of the coal face from 16 to 4 cm, that is, a decrease of 75%. This study provides theoretical guidance for roof support and coal face stability control of working faces under similar conditions.

Dec 26, 2022

By M. A. Reinsel

New technology for removal of nitrate from low-temperature waters has been developed. Typical results from the first operational-scale system (operating at a metal mine in Montana since January 1996) are over 90 percent nitrate removal at a flow rate of 130 gpm and a water temperature of 12°C. The system also operated successfully at flow rates as high as 300 gpm and water temperatures as low as 2°C. The ABC is advantageous because it is: a) cost-effective to design, construct and operate, and b) effective at cold water temperatures. The system can be designed for a variety of flows, nitrate concentrations, water temperatures and water qualities.

Jan 1, 1998

By Glenn Boyce, Paul Gribbon, Gary Irwin, Greg Colzani, Jim McDonald

This paper discusses the process utilized by the City of Portland Oregon’s Bureau of Environmental Services (BES) to procure and compensate Impregilo-SA Healy (I/H)for the West Side Willamette River Combined Sewer Over?ow (CSO) Project. The contract method is a three-phase process consisting of qualifications based contractor procurement, pre-construction phase design assistance/construction planning, and facility construction where the contractor is compensated on a cost reimbursable-fixed fee basis. The paper focuses on pre-construction phase lessons learned from the development of the contract general conditions, establishment of a construction budget and cost control program, incorporation of contractor recommended design changes, and development of a subcontractor procurement program for construction.

Jan 1, 2003

By B. D. Hansen

Newmont has been on a focused path of improving operations for many years. After the merger of Newmont and Santa Fe Pacific Gold, Newmont created significant synergies of over $50 million per year in Nevada, primarily through optimal ore movements and consolidation of various functions. During the current period of low gold and copper prices, Newmont has refocused its efforts on efficient operations worldwide. This paper will describe the methods and programs that continue to be implemented at Newmont's many mine facilities in Nevada. Newmont has used a combination of computer technology, optimal use of infrastructures, procurement strategies, functional consolidation, enhanced mine planning and a variety of available metallurgical processing options to decrease the cost of operations and increase profitability.

Jan 1, 1999

By R. R. Klimpel

During the period of 1973-79, an extensive period of research and development was undertaken by Klimpel and coworkers (1980, 1981, 1982a, 1982b, 1983. 1984, 1987) on the identification of a commercially viable chemically assisted approach to improving the efficiency of the wet grinding of coals and ores in tumbling media mills. The emphasis of the previous publications just listed was on the engineering use implications of controlling-slurry viscosity (rheology) in laboratory and plant scale grinding devices. In this paper, some discussion and results pertaining to the actual chemical screening phase will be presented.

Jan 1, 1988

By R. Sharma, S. Svoronos, S. Gupta, N. A. Abdel-Khalek

This paper presents the results of column flotation of a fine feed sample of Florida phosphate. A central composite design is used to study the main and interaction effects of parameters affecting column efficiency. The statistical design is also used to determine the optimum conditions. The results indicate that, depending on the experimental conditions, it is possible to achieve a concentrate of high grade and recovery. A concentration of 15 ppm of non-ionic frother is found to be enough to maximize the recovery at the pH of 9.5.

Jan 1, 1999

By Lee R. Martin, Michael R. Taber

Bird Balls™, the latest development in the ongoing battle at mine sites across North America, help to eliminate accidental avian mortality caused by birds ingesting cyanide leachate. Bird Balls™ are a 4-inch sphere made of high-density polyeth­ ylene (HDPE). They weigh 40 grams and are black in color to provide optimum life in UV intense environments. A floating blanket of bird balls totally excludes birds from a liquid surface. Federal agencies that enforce the Migratory Bird Treaty Act do not specify how to keep migratory birds out of leachate basins. Some state agencies, however, specify that a physical barrier must be in place to exclude migratory birds if cyanide levels are high enough to cause mortality. Industry standards for protecting waterfowl now include Bird Balls™ as well as net­ting, detoxification, and heap leach systems designed in such a manner that no exposed solution ponds or channels exist. Hazing is no longer an option. A bold statement to make? Perhaps, but W. R. Jeffress (1990) covers the subject well when he stated that, "Hazing techniques as a whole have not been effective in excluding waterfowl or other species of wildlife from toxic heap leach solution ponds or tailings impoundments. Research and devel­opment of the new 'Star Wars' hazing techniques, such as laser netting and radar systems, are interesting concepts and will pos­sibly offer an alternative to total physical exclusion or neutral­ization in the future. All of these methods are going to have to be thoroughly tested." For those who may want further docu­mentation, we have included a special reference section cover­ing hazing. R. J. Hallock (1990) stated that, "The Fish and Wildlife Service is particularly interested in migratory birds. In fact, a large portion of our effort, nationwide, is focused on migratory birds. Bird habitats are managed directly through the National Wildlife Refuge System and indirectly through other agency programs. We also have a responsibility to protect birds under the Migratory Bird Treaty Act. Most birds attracted to mine ponds are covered under this Act. The only migratory birds not protected under the Migratory Bird Treaty Act are English Sparrows, Starlings, and Pigeons. Since this is a treaty with five nations, the concept of acceptable losses does not apply. It is not a negotiable situation. There are a few exceptions noted in the Act, including prescribed hunting of selected waterfowl, scien­tific collection, and game bird farming. There is no exception for the loss of migratory birds exposed to solutions of cyanide."

Jan 1, 1996

By K. S. Gritton

The implementation of advance control systems brings with it the expectation of improvements in process performance and controllability. Specifically, expectations include a shift in the mean value of the gross measure of process performance, and/or a decrease in process variability. When determining statistically-defensible measures of these benefits care must be taken to preclude process parameters from biasing the determination. Specifically, the effects of ore type, shift personnel, water availability, etc., must all be separated from the effect on performance of the advanced control system. Methods are presented for separating the effects of process control from other process parameters. Examples of the required data analyses are also presented.

Jan 1, 2001

By Reinhold Schulze

Thiourea is being applied as an industrial leaching agent for gold and silver only in a few cases. A CIP technique was developed which eliminates most of the obstacles against its use. Mild conditions for precious metals stripping from the loaded carbon simplifies process conditions in comparison to cyanide CIP technique. Examples are given.

Jan 1, 1998

By J. Juilland

Over 10 percent of the United States of America or 41 percent of the Federal lands is managed by the Bureau of Land Management (BLM) as Public Lands. The mission is to manage the use of these lands and their resources. The way in which BLM carries out its mission is being refocused under the concepts of biodiversity and ecosystem-based management for the benefit of various human needs including environmental, social and economic values. The Bureau is developing methods to integrate the renewable and non-renewable resources programs into the concepts of biodiversity and ecosystem-based management. Exploration, development and extraction of energy or mineral resources on Public Lands are affected. The statements that following the next few pages are my personal views as a scientist (economic geologist -mining technologist) who is and has been involved for the last twenty years in the multiple-use management of Public Lands. They are not necessarily the position of the Bureau of Land Management, although much of the information on which I base my views comes from my experience with the BLM. The Bureau of Land Management (BLM) manages over 10 percent of the United States (270 million acres or 108 million hectares) which is 41 percent of the Federal Lands. Lands managed by BLM are known as Public Lands as opposed to the National Forest Lands which are Federal Land Policy and Management Act (FLPMA) of 1976 which in Sec. 102 states ??that it is the policy of the United States (7) ?that management be on the basis of multiple use and sustained yield??, the mission of the BLM is rapidly refocused under the concepts of biodiversity, ecosystems, and ecosystems-based management for the benefit of the environment, human needs and socio-economic values.

Jan 1, 1994

Development of computer-based information systems is predicated on the merger of rapidly developing computer technology and growing managerial demands for information. The focus of this section is on managing the development and implementation of information systems for the 1980's. It is the experience of the majority of contributors to this volume that among unresolved problems of major dimensions in a mineral organization are those of managing the computer-based information systems resource itself. There are three major reasons for this: (1) mineral information systems are relatively new to the senior management of a mining company or a mineral organization; (2) problems are compounded by a developing technology, a new type of personnel with a changing experience/education mix; and (3) an organizational structure and location which, in many organizations, are still being examined. The three authors in this section present aspects of managing the information systems function which, based on their experience, are common to the solution of the problem. The premise that the information systems function has been placed appropriately within the entire business plan of the firm has been made by the authors in their discussion of the various aspects of the management process.

Jan 1, 1979

By R. J. Lee

Asbestos analysis is conceptually simple. The objective, in most environmental analyses, is to determine the number of asbestos fibers per unit area or volume in a sample. The sample may be a consumer product, an ambient air sample, or a water sample. This determination is complicated by several factors: (1) sample collection and preparation, (2) counting techniques, and (3) operational definitions of asbestos in use. Three different definitions have been used in the study of environmental samples and are summarized in Table 1. The analytical procedure and detail required in the analysis vary with the definition of asbestos. Accordingly, this may be the only type of environmental analysis where the definition of a substance dictates the choice of analytical methods, and the rigor demanded of the analysis. Lead, arsenic, or beryllium are sub- stances having a constant definition and the method of analysis chosen depends on the concentration and precision required. However, the meaning of the term asbestos fiber is dependent on the eye of the beholder. Macroscopically, asbestos has certain physical properties that make it highly useful. Rockforming minerals do not display similar characteristics. Now, the question arises as to how three definitions of asbestos came into being. This is a result of two factors: (1) the definition of asbestos on any scale intrinsically involves the morphology or shape of the material, and (2) the advent of the transmission electron microscope permits detection of asbestos fibers and other mineral fragments in a size range where the physical properties of asbestos such as tensile strength, flexibility, or thermal resistance are difficult, if not impossible, to measure. There is a good deal of controversy about which definition is most appropriate for regulatory purposes because of a lack of appropriate health effects data (Cooper, 1978). Most differences of opinion center on the questions surrounding the following: 11 Morphology-Is a 3:l aspect ratio an appropriate medical or physical lower limit for the definition of an asbestos fiber? 2) Length-Are asbestos fibers shorter than some arbitrary length (5 pm) as hazardous as longer fibers? 3) Mineralogy-Is the mineralogical distinction between asbestos and nonasbestos minerals medically significant? While these questions are directly resolvable only with the biological and health effects data, ultimately such data reflects the ability of analytical procedures to fully characterize the materials used in health effects studies on animal models, and to monitor the exposure to particulates with different physical attributes in the workplace or community (Cooper, 1978). The following sections outline the analytical problems involved in distinguishing the asbestos and nonasbestos varieties of the same mineral; the analytical procedures available for identifying asbestos and measuring its concentration in environmental samples; the ability of these methods to distinguish asbestos fibers from nonasbestos particles; and their precision and reproducibility. Finally, we suggest some future directions in terms of definition and procedure that would greatly improve the quality of such analyses. ASBESTOS VS. NONASBESTOS Asbestos that is mined commercially belongs to two mineral families; amphibole and serpentine (Zoltai, 1978, Wylie, and Steel, 1978). The

Jan 1, 1986