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By Angelina Anani, Nilufer K. B. Akbulut, Sefiu O. Adewuyi

Crucial information about safety, design, and operation can be utilized in underground mines from ground movement data. Communicating the information and exploring new findings can be a challenge in a decade where there is an ever-increasing volume and velocity of data due to advancements in mining technologies. This challenge escalates for geotechnical data as it is multidimensional, depending on the space and the rate it takes place. To tackle this challenge, geotechnical engineers should focus on utilizing simple yet compelling visualization of rock mass data in 3D. Competent visualizations of ground conditions as a Trigger Action and Response Plan (TARP) could ease the communication of safety concerns and the exploration of rock mass displacement and strain surrounding an opening at an underground mine. Therefore, this study focuses on using scientific visualization methods by rendering geotechnical data over the surface of a 3D mesh model to display TARP levels. The study is conducted at the San Xavier (SX) Underground Mine Laboratory’s East decline. The project aims to produce visualizations that optimize the use of geotechnical data in near-real-time.

Feb 1, 2025

By Hugo E. Camargo, Amanda S. Azman, Brian Kim

Repeated noise exposure and occupational hearing loss are common health problems across industries and especially within the mining industry. Large mechanized processes, blasting, grinding, drilling, and work that is often in close quarters put many miners at an increased risk of noise overexposure. In stone, sand, and gravel mining, noise is generated from a variety of sources, depending on the type of ore being mined as well as the final consumer product provided by that mine. Depending on the source of noise generation, different strategies to reduce and avoid that noise should be implemented. The National Institute for Occupational Safety and Health (NIOSH) has evaluated the noise profile at three operational surface stone, sand, and gravel mines. A-weighted sound level meter data as well as phase array beamforming data were collected throughout the mines in areas with high noise exposure or high personnel foot or vehicle traffic. Sound level meter data collected on a grid pattern was used to develop sound profiles of the working areas. These sound contour maps as well as phase array beamforming plots were provided to the mines as well as guidance to modify work areas or personnel traffic to reduce noise exposure.

Jan 6, 2022

By R. R. Klimpel

Over the last six years, several new commercial families of sulfide mineral collectors have been developed. This paper summarizes some plant data and use experiences gained with each of these product families. The first is a series of products (F-series) based on a chelation mechanism of attachment. The second of these families is a series of products (S-series) based on an electrochemically controlled mechanism of attachment. The major advantage of the F-series collectors is the very high metal recovery capability in complex ores involving Au, Pt, Zn, Ni, and mixed Cu minerals. The major advantages of the S-series collectors are the very high pyrite rejection capability along with reduced lime requirements in Cu/Mo plants.

Jan 1, 1995

By Lynn B. Hales

The Supervisory Computer System at Cities Service copper mine and concentrator at Miami, Arizona was installed at Pinto Valley in the spring of 1975. Design and specification [l] of the digital system was initiated jointly by key plant personnel at Pinto Valley and staff of Cities Service Research and Development Company. The Pinto Valley digital system [2] may be classified as a supervisory control system of hierarchical design. There are three fully independent satellite computers which retrieve and reduce the raw plant data from each of the three main operating areas - the primary crushing plant, the fine crushing plant, and the grinding and flotation plant. While the three satellite computers are core resident systems, the master computer is a disc-based operating system which also interfaces with a computer controlled on-stream x-ray analyzer system. Figure 1 illustrates the basic system configuration [3]. The software systems required to support a large system are quite diverse and vary greatly in function. The philosophy followed in dividing the software into three categories was designed to: 1) fully utilize existing process knowledge of technical staff; 2) delegate certain software tasks to outside sources already skilled and trained in software development; and 3) maintain final control over the design and operation of each system.

Jan 1, 1976

By B. K. Mishra

In order to maintain higher grinding efficiency in tumbling mills the mill interior and dynamics must be known. For this purpose, several different types of non-intrusive methods have been proposed and are being tried in the industry. We have made an effort to develop a diagnostic tool based on vibration signal. Here we discus results of our experiments pertaining to ball as well as SAG mill. In each case, a triaxial accelerometer was used to capture mechanical vibration generated due to the tumbling action of the charge. The vibration signal was transmitted to a remotely placed computer and the signals were analyzed by standard signal processing technique. In case of a ball mill (5m diameter), qualitative mill information could be obtained by correlating the vibration signal to feed rate and mill filling. An effort was also made to identify different motion characteristic of the charge by analyzing its vibration signal. In case of the SAG mill (10m diameter), liner wear was estimated by comparing the vibration signal emitting out of a freshly lined mill with that of a worn out mill.

Jan 1, 2011

By David R. Gossett

For the 22nd year, the chance to exchange knowledge, experience and business cards drew hundreds of mining and phosphate professionals for a two-day regional Phosphate Conference in Lakeland, Florida Nearly 400 people participated in the October conference, which focused on the phosphate industry?s future success. There were 41 exhibitors, 13 program advertisers and 23 sponsors among those supporting the conference. It was chaired by David Gossett, 2006-2007 SME Florida Section Chairman. In the opening panel session that he chaired, John Garlanger (SME) of Ardaman and Associates posed the questions; ?How successful has the industry been? How do we measure it and what factors contributed to the industry?s success? How long will the ethanol boom last? Can the industry obtain the permits it needs to mine for the next 30 years? Can the industry attract and retain the quality of workers it needs??

Jan 1, 2008

By Veerendra Singh, NILAMADHABA SAHU, ARIJIT BISWAS

Manganese (Mn) ferroalloys are chiefly consumed in the steelmaking process as a deoxidizing agent or as an alloying element to produce high-quality steels. These alloys are typically produced in a submerged arc furnace using coke, fluxes and manganese ores of a specific manganese/Fe (Mn/Fe) ratio. Preferred-grade manganese ores should have Mn content greater than 46 percent and Mn/Fe content greater than 5 to produce commercial-grade, high-carbon ferromanganese [1]. Selective mining of high-grade Mn resources has created a scarcity of these resources, which is emerging as a major challenge for the manganese and steel industry. Manganese ore resources are mainly distributed in South Africa, with about 32 percent; Ukraine, with about 17 percent; Australia, with about 17 percent; and Brazil, India, China, Gabon and Mexico, with lesser amounts.

By Ruipeng Qian, Pengfei Wang, Guorui Feng, XianJie Du, Jun Guo, Yuxia Guo, Tingye Qi, JinWen Bai

"A numerical modeling was conducted to describe the behavior of overlying strata on the longwall top coal caving face for exploitation of a 16.8 m thick coal seam. Three typical structural models, including the Cantilever Structure (CS), Lower Cantilever and Upper Hinged Arch Structure (LC&UHA), and Lower Arch and Upper Voussoir Beam (LA&UVB), were developed. Based on mechanical analysis of the different structures of the key strata, and considering the behaviors of the broken igneous rock strata, a method was proposed and applied to estimate the structures of the overburden strata. The results had been verified by a field micro-seismic monitoring test. The paper provides a foundational method to determine the shield loadings for the top coal caving longwall face.INTRODUCTIONLongwall top coal caving (LTCC) is a highly productive underground mining technology which has been widely applied to the exploitation of the thick coal seams in China and other countries due to its high efficiency (Ju and Xu, 2013; Ju, Xu, and Wang, 2011; Liu et al., 2009). In recent years, a large amount of research on mining pressure forecast, strata control, and mechanical equipment improvement of the LTCC technology has been carried out, which greatly advances the field application of the technology (Liu et al., 2009; Yu, 2016; Dou et al., 2014; Feng et al., 2011; Chen and Li, 2011; Yin, Yan, and An, 2008). In 2006, the LTCC technology was first applied to the exploitation in a 20 m thick coal seam at the Tashan Coal Mine in China (Yan et al., 2011). Ten years of mining at the Tashan Coal Mine has highlighted the importance of the support management in controlling the roof strata on the extra-thick LTCC face. The mining pressure is closely related to the structural features of the overlying strata and its movement laws (Yu, 2016; Dou et al., 2014; Feng et al., 2011). However, the distributions of three zones—caving zone, fracture zone, and deformation zone—on the fully mechanized caving longwalls changed significantly with the increase in thickness of the coal seam (Chen and Li, 2011). The behavior changes of the roof strata led to abnormal pressure in the mining face and resulted in the difficulty of surrounding rock control (Yin, Yan, and An, 2008; Liu et al., 2009; Yan et al., 2011; Gong and Jin, 2008). Therefore, the theoretical research focused on the behavior of overlying strata to reveal the laws of mining pressure has important theoretical significance and practical value.Many classical studies (Qian and Shi, 2003; Feng, 2010; Yu, 2015; Yu, Yan, and Liu, 2012) had been done to describe the behavior of overlying strata in the mining process. It has also been reported that magma intrusion causes an important effect on the surrounding rock, coal, and methane (Wang et al., 2005; Liu et al., 2007). On the one hand, the property and structure of the coal seam was obviously changed by the magma intrusion and resulted in a potential danger of a gas outburst during the mining process (Chen et al., 2012; Wang et al., 2014). On the other hand, the hard igneous strata and the joints occurred with the magma cooled, causing an abnormal behavior of overlying strata and resulting in a series of dynamic disasters during mining (Xuan, Xu, and Lu, 2014; Lu et al., 2016). In fact, many coal fields in China are intruded by igneous sill, including the Datong, Shuozhou, Huainan, and Xuzhou coal fields (Chen et al., 2014; Wu, 2011). The 3–5 coal seam at Tashan Coal Mine in Datong coal field is very thick and is intruded by a large area of layered lamprophyre rock. Face falls and shield failures occurred frequently during the face retreat."

Jan 1, 2019

By P. Rostami

It is important to study the ventilation system in order to better design and control of the working environment in deep underground mines. With increasing depth, heat, and humidity performance may be reduced and impair the attention of workers. The purpose of this paper is to apply a complex; development-end model configured in the MULTIFLUX program, developed at the University of Nevada, Reno, USA. The MULTIFLUX development-end model template has been benchmarked against measurement results from two UK coal mines in previous studies. The present study is a test of MULTIFLUX application in a metal mine. The model incorporates the simulation of the air flow field in the drift and the auxiliary air duct; simultaneous heat and humidity transport from the drift wall; heat and mass exchange between the air in the drift and the ducts; and the evaporation of process water and/or condensation of vapor as governed by the psychometric conditions. The results are compared with field data, measured at the Lucky Friday Mine (LF) in Idaho, USA, an underground mine and also shown between the results from the MULTIFLUX-based model, and those from another program, Kduct, developed at the Kyushu University in Japan.. Gao, K. Uchino & M. Inoue Fukuoka, Japan (2002)?

Jan 1, 2011

By Robin J. Batterham

We still need to innovate, but it is getting harder. The real price of metals is declining, return on shareholder value is lower than other industries, and there is a shorter-term focus on staying viable in a capital-intensive industry where timeframes for implementation of new technologies can be long (+I5 years). In this environment, the levels of R&D spent by major minerals companies are remaining steady at around 0.2%-0.5% of revenue. This is not large and to remain viable in the future, we need to be smarter about the way in which we do R&D. The mining industry is a knowledge-based industry. Driving down the cost curve demands innovation, which demands knowledge. To be smarter and more effective in our approach to innovation, a new paradigm is required Generating, capturing and using knowledge has evolved from Mode 1 (discipline based and clear distinction between basic and applied research) to Mode 2 (multidisciplinary, team-based approached with flow between basic and applied activities). Mode 2 is now seen to be much more efficient and to deliver better appropriability (Tegart 2003). To survive, we need to innovate, and the best way to do this is collaboratively. Some examples and pointers for the future will be given in this paper. THE CURRENT SITUATION The Rand report and other recent studies have painted a grim outlook for the mining industry. The real price of metals continues to decline (Figure 1) and profit margins remain thin. This is reflected in shareholder returnwhich are well below other industries (Figure 2)-and current management strategies-which reflect something of a "survival mode." The current focus for most mining companies is on short-term, incremental gains

Jan 1, 2004

By S. Constantinides

Over the past 100 years we have witnessed a revolution in permanent magnetic materials. Prior to 1932 electrical machinery depended upon steels for both the soft and the permanent magnet structures. Because permanent magnet steels were easily demagnetized, motors, generators, loudspeakers and similar devices often used the interaction between two electromagnets. Motors and generators were mostly of the induction type, depending for function upon induced fields. The discovery of Alnico in 1931 and its rapid commercialization presaged an expansion of the industrial revolution and today, permanent magnet structures are widely utilized. [ ] DEVELOPMENT OF PERMANENT MAGNETS Act 1: Early Days of Permanent Magnets Alnico, which stands for aluminum, nickel and cobalt, is a family of alloys with similar structure and processing requirements. Additional elements, such as copper and titanium, are present in minor amounts to optimize magnetic properties. Alnico is known by many trade names around the world including Alcomax, Hycomax, Ticonal, Nipermag, Koerzit, Oerstit, Nialco, etc(1,2,3). In addition to the generic name ?alnico?, it is usually appended with a number representing the magnetic grade.

Jan 1, 2011

By Andrew Chegwidden, Tara Wilk

Construction of Shaft 17B-1, a part of The New York City water supply system, required an excavation of approximately 38 m (123 ft) through water-bearing overburden soil and more than 152 m (500 ft) of gneiss bedrock to make a connection to Water Tunnel No. 3. Ground freezing was the specified method to provide temporary earth support and ground water control for the overburden material. The ground freezing process relied on a supplemental geotechnical investigation and comprehensive laboratory testing of the frozen soil to evaluate the potential long-term creep behavior of the soil and the elimination of a temporary lining system. This paper describes that process as well as the drilling and installation methods of the ground freezing system. Additionally, the methodical system of excavation and insulation is discussed that permitted a safe and timely excavation followed by the installation of the permanent concrete liner.

Jun 13, 2023

Newmont?s Twin Creeks Mine, located in northern Nevada, is producing gold ore from surface mining operations. The ore is currently processed at three different on site facilities depending on the ore type and the grade. The processing facilities operate under stringent geochemical blending constraints that must be met from mine ore deliveries and off site sourced ore. To analyze various strategic options, the technical team utilizes the mathematical optimization approach. However, due to the size and the complexity of the operation, there are unique challenges in optimizing life of mine production scheduling. This paper describes those challenges and the methodology developed to take advantage of different scheduling software systems that effectively compensate each other and result in reasonable guidance. The paper also describes how those scheduling results are reflected in detailed mine plan and cost estimate work.

Feb 27, 2013

By D. L. Boreck

With increasing land development, the potential of fatalities from abandoned mine shafts increases. To minimize potential liability, shaft closure should be a critical part of mined land reclamation. The Bureau of Mines is conducting research into using lightweight foam concrete in sealing abandoned coal mine shafts. A demonstration seal consisted of a 3m thick foam concrete plug to provide lateral stability inside the shaft. A high density concrete cap provided load-bearing capacity for a 100-year service life. The USBM has also completed research into changes in foam concrete when it is pumped or dropped from different heights. It is concluded from the research that foam concrete can undergo significant air loss with pumping or dropping. This foretells significant changes in the characteristics of the concrete as well as an increase in the weight and cost of the in-place concrete seal. When using foam concrete to seal abandoned mine shafts, care must be taken to minimize air loss during placement.

Jan 1, 1994

By Harland E. Cofer

A computer-assisted resources and sedimentological study of the Andersonville, Georgia kaolin-bauxite district was begun in 1975 under a grant from the Office of Mineral Resources of the U.S. Geological Survey (Grant # 14-08-1110-G-173). A preliminary report on the kaolin and bauxite resources of the district has been placed on open file at the U.S.G.S. in Reston, Virginia; the Georgia-Geological Survey in Atlanta, Georgia; and Georgia Southwestern College in Americus, Georgia. In addition to a resources estimate, the objectives include the determination of the mineralogical variation, sedimentological parameters, and paleogeographic patterns of the deposition of the high alumina materials and their associated sediments. In the process of compiling data for the resources estimate, isopach maps were developed that provide information as to the shape, size, and distribution of the kaolin deposits and the kaolinitic sediments that contain them. These or similar maps developed for other districts can be useful exploration tools.

Jan 1, 1977

By W. Burger

Mechanical excavation methods can significantly improve excavation performance and labor safety compared to drill and blast operations. Herrenknecht has developed a mechanized shaft sinking method for soft and medium strength rock. This system combines innovative technologies which allow simultaneous excavation, removal of cut material and the installation of rock support. This Shaft Boring Roadheader ?SBR? is flexible in diameter and can be used in shafts with changing diameters and different shaft support requirements for depth up to 2,000 m. During regular excavation personnel are not required to access or work on the shaft bench. The boom used to cut the shaft profile is based on roadheader technology.

Jan 1, 2012

By S. C. Sun

A study(1) on the sulfuric acid extraction of alumina from some Pennsylvania ferruginous clays indicated that the published electrolytic method(2)(3) seems to be more efficient than the known chemical methods (4-9) for removing iron from the leach liquor. The main disadvantages of the chemical methods are the consumption of excessive amounts of reagents and/or the precipitation of prohibitive amounts of aluminum. In the electrolytic method, iron is deposited on the mercury cathode, while aluminum is not and remains in solution. This method, however, had been handicapped by the lack of an effective and economical way to purify the contaminated mercury cathode.(7)(l0). Described herein is a scheme for cleaning the mercury cathode, and for recycling the clean mercury back into the electrolytic cell. Armed with such an apparatus, the effects of applied potential, temperature, and operation time on the electrolytic separation of iron from aluminum sulfate solutions were determined. For the sake of comparing results, a term, removability, was coined to represent the percentage of iron amalgamated per unit height of electrolyte (cm.), per unit surface area of cathode (cm.2), per unit of operation time (second).

Jan 1, 1968

By G. A. Christie

This paper presents a vision system capable of providing an accurate estimate for the volume of stockpiles using 2D images. By imaging a stockpile from multiple viewpoints with a two-camera system, a 3D point cloud of known scale is generated using image-based 3D reconstructions. With a small amount of user interaction, the points that correspond to the surface of the stockpile are extracted and used to measure the volume. The hardware required for the two-camera system is light enough to be carried by a small unmanned aircraft and is a cheaper alternative to LiDAR while still being competitive in terms of accuracy. When testing the volume measurement algorithm on a stockpile of known volume, the measured output was found to have less than a 3% error from the ground truth.

By A. Cole, F. Porretta

Barrick Gold recently implemented an oxygen roasting process to treat carbonaceous ore from its Goldstrike property in Nevada. One of the key project challenges was the design of the roaster gas cleaning system, which was driven by the requirements of a strict air permit and the need to achieve very high reliability. The roaster gas systems include multiple stages of wet particulate collection, a dual alkali SO2 scrubber, mercury scrubbing, CO oxidation and NOx reduction. This paper describes the gas system, the influence of regulations on project implementation, and performance of the system.

Jan 1, 2002

By Ma. X.

Passive seismic imaging is applied in underground mining to analyze the stress redistribution after the occurrence of a major seismic event. The velocity model is established to be utilized in velocity inversion. By comparing the images from velocity tomography on two different time scales, the average velocity of a mining area decreases significantly after the major event. It is highly likely that the stored energy level drops due to the occurrence of a major event. Also, total energy stored in micro-seismic events for each day is summed up and the energy change trend is plotted to illustrate the correlation of energy with a major event.

Feb 27, 2013