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By Enrique Fernández

INTRODUCTION The high speed rail link between Madrid and Asturias, in the North of Spain, has encountered in the Cantabrian range the biggest challenge of the whole line, a very deep tunnel, 25 km long through a foreseen difficult geology. This tunnel was divided in the following four lots for construction: ¦Lot 1: Pola de Gordón- Folledo. L=10,7 km ¦Lot 2: Folledo-Viadangos. L=4,166 m ¦Lot 3: Viadangos- Los Pontones. East tube. L=10,4 km ¦Lot 4: Viadangos- Los Pontones. West tube. L=10,4 km. Dragados S.A. leading a JV was contracted to design and built the Lot 2 on the captioned Pajares High Speed Railway Tunnel. The Lot 2, comprising the middle third section of the 25 km long tunnel has an additional challenge: the construction of one access from the surface to allow it own construction. Feasibility reports and preliminary design do not foresee the use of TBM due to the risk of squeezing ground at the deepest area of the tunnel. On the other hand, conventional NATM excavation of the twin tunnels and ancillary works, including access shafts were against the expected construction schedule by the client, due to the poor ground foresee at the early stage.

By Ajit Godbole, Ping Chang, Ramakrishna Morla, Purushotham Tukkaraja, Shivakumar Karekal

This paper presents the optimum auxiliary fan(s) location to control air recirculation in dead-end workings where dieselpowered vehicles operate. Investigations were conducted with various secondary fan locations from the dead-end crosscut with varying the intake air quantities using a 30 m3/ s capacity twin 75 kW auxiliary fan and 45 m3/ s capacity twin 110 kW auxiliary fan to control air recirculation and DPM. The results showed that if the drive intake airflow rate matches the fan capacity, air recirculation will occur even when the fan is located 10 m away from the crosscut entry. Results also showed that if the intake drive air quantity was greater than or equal to 150% of fan capacity, no recirculation was observed when the twin 75 kW fan location was at least 5 m and the twin 110 kW fan location was at least 10 m away from the dead-end crosscut access.

Oct 18, 2022

By H. H. Murray

The largest reserves of palygorskite in the world are located in Anhui and Jiangsu Provinces in East Central China. The deposits are Middle Miocene in age and range from 3 to 6 m in thickness. The deposits are the alteration product of basaltic volcanic ash. The Chinese Geological Survey estimates the palygorskite reserves are in excess of 200 million tons. The elongate particle shape results in unique colloidal properties. Large quantities are exported to Japan, Taiwan, Southeast Asia, New Zealand, Australia, and West and Gulf Coasts of the United States. The markets include agricultural carriers, paint, joint tape compounds, animal feed binders, catalyst support, drilling muds, and suspending agents for chemicals, pharmaceuticals, and medicines. The viscosity is high and the quartz content is generally 5% or less.

Jan 1, 2009

The ability to optimise a concentrator from mill feed to final products requires a simulator which integrates comminution, classification and separation modelling. In order to model this range of processes, such a simulator must handle a variety of information about the ore. The AMIRA P9 project has developed a whole-of-concentrator simulation capability which brings together a texture-based model of mineral liberation, quantitative X-ray micro-tomography analysis to measure the inputs required by this model, and a multi-component simulator software framework. In the context of this approach, the term ?multi-component? implies the ability of the simulation to handle many particle properties simultaneously; for example size, composition, density, floatability etc. The simulation software framework provides the means to manage the flow of data around a circuit flowsheet, allowing each process model to access the information relevant to that particular model. A case study based on plant data from a gold-bearing pyrite concentrator is used to demonstrate the capabilities of the multi-component approach in simulating circuits which contain comminution and separation processes.

Feb 27, 2013

By V. Rajaram

Rock reinforcement systems are used in open pit and underground mines to stabilize the rock mass in-situ and provide safe working conditions. Significant progress has been made to date in the design and implementation of rock reinforcement systems to accommodate bad rock conditions and larger excavations. However, the rationale for the design of rock reinforcement systems remains essentially the same and can be categorized into three groups, namely 1. to create a beam of competent rock in stratified formations, 2. to resist sliding motion in jointed rock, 3. to passively support the superincumbent loads in highly stressed ground. Case histories of the rock reinforcement sys¬tems that illustrate these design approaches will be presented in this paper.

Jan 1, 1983

By Monserrat Rebolledo, John L. Uhrie, Candice Simms

Jetti Resources has developed a catalyst which overcomes the passivation of primary sulfides, enhancing the heap leach recovery of copper from chalcopyrite. It is important to emphasize that heap leaching of copper sulfides, whether with or without the Jetti catalyst, is a biooxidative process. We have demonstrated the efficacy of Jetti’s technology in bioreactors, with a chalcopyrite-dominant porphyry ore. In the presence of Jetti’s technology, optimal bioleaching conditions significantly increase copper extraction by 2.6 times that of the baseline.

Feb 1, 2025

By Deborah A. Peacock

"Outer space technology and exploration have reached a tipping point, so that mining and mineral processing in outer space is now a certainty and not a dream. Several competing companies worldwide are on the way to building spaceships to land on the Moon and eventually mine the Moon and asteroids for volatiles, rare earth metals and Helium-3.The Google Lunar XPrize offers a $30 million prize1. China has recently landed a spacecraft on the Moon. The European Space Agency, with cooperation from the United States, has landed a spacecraft, Philae, on a comet. And, Mars One is planning a one-way trip to establish a settlement of humans on Mars.How and why are the Moon and asteroids and their resources of interest to private space industry companies? Why are the Moon and asteroids viewed as a potential business venue?Geology of the Moon and asteroids — Why do we want to mine there?Space enterprises are actively working toward establishing and operating lunar and asteroid mining locations for resource extraction, resource processing, conversion to salable products and distribution of the products and services in space and to Earth and beyond2.Forty-five years ago, the Apollo manned missions to the Moon returned rocks and regolith to Earth, which were studied and analyzed. What they found was that the Moon contains valuable minerals and resources. These minerals are largely due to meteor and asteroid impacts, which have, over eons, created this mineral-rich regolith. These impacts have occurred on Earth as well, for billions of years, particularly early on in the history of the solar system. However, on Earth, wind, water and vegetation have erased most of these impacts. On the Moon, in contrast, the only weathering is caused by subsequent impacts and the solar wind."

Jan 1, 2017

By Ralph W. M. Lai

The liquid membrane separation process was first patented in 1968 for separating hydrocarbons.(1-4) This stimulated many researchers to join in the area of separating organic compounds. l Since then, its applications have been extended to the removal of contaminants from waste water,(12-33) encapsulation of enzymes and/or microorganisms for reaction and/or separation, (24-28) oxygenation of blood (artificial lung),(19) removal of toxins from blood (artificial kidney)(26,20) and metal extraction.(31-63) This paper discusses the possible process schemes for using liquid membranes to separate and concentrate copper ion from its acidic leaching solution.

Jan 1, 1982

By Chelsea Woodward

The Spokane Research Laboratory of the National Institute for Occupational Safety and Health has demonstrated a prototype hydrogen-fueled mining vehicle as an alternative to diesel equipment in underground mines. Safety and control systems were added to allow a 70-kW rubber-tired hydrogen vehicle, originally developed by the U. S. Bureau of Mines and Hydrogen Consultants, Inc. (now Hydrogen Components, Inc., of Littleton, CO), to be tested. This work began in late 2000 and culminated with a Mine Safety and Health Administration fire safety review and field tests at the Stillwater Mine in Nye, MT, in 2004.

Jan 1, 2006

By W. Langer

Of the 50 or so most often utilized industrial minerals, more than two thirds are, or have been, produced in the western states of Arizona, Colorado, Idaho, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, Utah, and Wyoming. Some commodities, such as natural aggregate, currently are produced in all 13 states; others such as beryllium and iodine are produced in only Utah and Oklahoma, respectively. Together, the 13 western states make a significant contribution to the US industrial minerals industry.

Jan 1, 2007

By K. Short

Today?s modern mining operations have literally dozens of applications and systems generating data whose information very often, are not crossed or centralized for operational decisions. In remote locations, the information and situation awareness is typically limited to the location itself. In addition, access to that information is limited to a small, select group of personnel that have received training on how to interpret the results. When the situation affects another area of the mine then information is relayed to the applicable areas involved. Few workers have time to analyze the situation thoroughly, to see how it affects the mines symbiotic relationship within all areas of production. If the capability to correlate and measure events and situations that affect your overall key performance indicators are not in place, the opportunity to identify process improvement becomes more difficult.

Feb 27, 2013

By J. C. Stankus, K. J. Ma, D. Faulkner

To protect mine personnel and moving equipment at underground roof fall areas, mine operators typically install steel sets, which are covered with wooden blocks and backfilled with an expanding-type cement material. In large roof falls, the cost of void backfilling becomes prohibitively high, causing some mines to leave the voids open. However, the durability of wood over time and the capability of the steel set and wood lagging to resist falling rock are unknown. This has caused concern for the U.S. Mine Safety and Health Administration (MSHA) and ground control engineers. During the last few years, Keystone Mining Services, LLC developed various impact-resistant steel set designs that were approved by MSHA and installed in various underground fall rehabilitations. This paper presents an impact-resistant steel set design methodology, including (1) steel set design per AISC national standard, (2) design, development and laboratory testing of a waterproof coated impact-resistant lagging panel and (3) impactresistant steel set design based on the law of conservation of energy. Two underground cases will be included detailing the application of the system.

Jan 1, 2011

By Norbert T. Rogers

An accepted statement of fact is that, next to agriculture, transportation is the second most important industry in the world. The transportation networks of the United States have greatly contributed to our nation's growth and prosperity. The objective here is to make the reader aware of the need for communication between geologists, mining engineers, purchasing agents, and transportation managers. Only through a cooperative effort is it possible to reap the benefits of transportation in the industrial minerals field. Transportation is often thought of in terms of trucks, rail cars, barges, and covered wagons. There is much more. Corning Inc. Corning Glass Works is a worldwide organization with more than $2 billion in annual sales. It supplies more than 60,000 different products a year to some 47,000 customer firms and millions of individual consumers. Corning operates 32 of its own plants worldwide and is also an investor with a 50-50 or minority position in 24 affiliated companies in 11 countries. Corning competes in four broad business categories: • specialty glass and ceramics; • consumer housewares; • laboratory sciences; and • telecommunications Binding these four sectors together is the glue of technology. Coming's research laboratory, established in 1908, was one of the first in American industry. That early commitment to research has never wavered. Today, Corning spends annually on research and devel¬opment, as a percentage of sales, at double the average rate for all manufacturing industry in the US. Some 1500 scientists, engineers, and support personnel are now employed at the company's research and development centers in the US, Japan, and France. Petalite background A family of materials melted conventionally as a glass, then converted by special processing to a ceramic was invented in 1957. One of the basic minerals in this glass ceramic product is petalite. Petalite is a monoclinic mineral with a framework silicate structure and a low iron content, about 0.06% Fe2O3. Petalite is found in very few places throughout the world and no commercial petalite deposit has been found in the United States. Sizable deposits occur in Zimbabwe, Southwest Africa, Brazil, Australia, the Soviet Union, and Sweden. Coming's purchasing and geology departments located a source of petalite with proven reserves in what was then known as Rhodesia. The supplier was Bikita Minerals. The relationship with Bikita was one in which Bikita supplied bulk ore that Corning processed into a finished material at its US facility. This bulk ore method of shipment resulted in high losses through contamination and processing. It also caused tank upsets at the Corning plant because of iron contamination picked up through the numerous handlings of this product in bulk. The relationship with Bikita continued until 1965 when the white political leadership of Rhodesia declared its independence from Great Britain. This led to the imposition of international sanctions. The sanctions were lifted in 1980 and the relationship with Bikita was reestablished in 1983.

Jan 1, 1989

By L. W. Berry

Drill and blast planning is critical to successful mine production, both in timing and in results. However, typical planning, reporting, and information exchange usually involves large quantities of data collated in a discordant set of spreadsheets, databases, and reports. Collecting, analyzing, modeling, and distributing all data necessary for efficient drill and blast operations is time consuming and cumbersome. MineSight Axis Drill and Blast provides an extensible core of functions, seamlessly integrated with other MineSight software tools, to make sense of this information. The benefits of improving the management of drilling and blasting processes are immense and result in improved fragmentation at a lower cost, improved shovel and truck productivity, and enhanced ore processing.

Jan 1, 2011

By Syd S. Peng

University research in the U.S. consists of three components; faculty, funding, and graduate students or postdoctorals. Individual faculty is the unit area of research that is not limited, although faculty normally performs research in their areas of expertise. Faculty can and often do join with other faculty in multidisciplinary research. Faculty research achievements or reputation reflects the standing of the program and university. Therefore, research is highly encouraged and regarded within the university community. Graduate students are the work force of faculty research and doctoral students are preferred for high-quality products. The federal government provides the majority of funding sources, with the remainder coming from industry, state government and others. Compared with other engineering majors, the mining engineering programs in the U.S. are unique in that they: ? Are small in terms of the number of programs, and number of faculty and students in each program. ? Serve a single industry (i.e., mining) and are thus cyclic, reflecting the up and down economic state of the mineral industries. Enrollment statistics during the past 70 years show that a cycle consists of approximately 30 years with the first 10 years up, followed by 20 years down. ? Have curriculum designed to emphasize and thus serve for either the coal, hardrock or industrial minerals industries. These unique features make mining engineering programs hard to manage in university environments. Funding for mining research has relied primarily on the federal government, i.e., the former U.S. Bureau of Mines (USBM) and currently the National Institute for Occupational Safety and Health (NIOSH). The mining industry does not directly perform, nor sponsor research projects. Federal funding provides primarily in-house research. In the last four decades, federal extramural funding was only available when Congress appropriated extra funding in response to mine disasters. For instance, a string of coal mine explosions in the mid to late 1960s prompted Congress to enact the Coal Mine Health and Safety Act of 1969. It provided massive research funding from 1970 to 1983 covering all mining-related subject areas. From 1984 to 1995, federal extramural research funding was minimal, through two generic mineral technology research centers for selected mining engineering programs. In 1995, Congress closed the USBM and transferred the health and safety of miners program to NIOSH. Federally-funded extra-mural research practically stopped from 1995 to 2006. In 2006 and 2007, in response to a series of disasters, including those at Sago, Aracoma, Darby and Crandall Canyon, Congress again appropriated funding for short-term re-search in selected subjected areas such as underground tracking and communication, mine seal and ventilation, and deep cover pillar extraction. Therefore, to develop a meaningful academic mining research program during the past three decades, funding needed to be drawn from other sources such as the mining industries. A ?meaningful? program requires a sufficient amount of consistent funding in order to produce effective results. A review of federally funded extramural research pro-grams shows that a great majority of contractors/grantees are private entities, involving few mining engineering faculty. This, in part, is due to the fact that mining engineering involves so many different subjects. Therefore, a small mining engineering program can only have resources to cover teaching in the core subject areas (i.e., extraction, ground control, ventilation and material handling), at best. In this respect, a successful and meaningful academic mining re-search effort requires strong supporting programs such as geology/geophysics, structural (applied) mechanics, material sciences, compute/software application, etc. Therefore, academic mining research had to rely on private sources such as coal companies, in the author?s case, for sustained funding in the past three decades. Relying on funding from coal companies presents several problems. The projects were small and considered routine consulting projects requiring practical answers in a very short time frame. This is not really suitable for academic research, for which the major goal of research is the training of graduate students. These short-term projects vary with time and mines, most of which are driven by U.S. Mine Safety and Health Administration (MSHA) or U.S. Office of Surface Mining (OSM) regulations. So sustained funding under such condition requires broad experience of coal mining operations, which is also not well-aligned for academic research where faculty tends to specialize in a narrow field. Consequently, under such a funding environment, it is important to keep in mind how to develop long-term academic research objectives from conducting small short-term consulting projects that require quick solutions. In other words, how to look beyond the quick answers and to develop broader and more fundamental theories applicable to other situations that advance the-state-of-the-art. In order to achieve this objective, faculty must act as the connecting link because graduate students come and go. Faculty must know the detail of each project such that they know what are the important unsolved problems, what to assign to specific graduate students and how to guide the next group of graduate students to continue the development and advance the mining science. Under such funding environments, the most effective way to conduct academic mining research and ensure quality products is to maintain a research group consisting of postdoctoral, PhD, and MS students of various rankings such that the senior ranks can assist in guiding the junior ranks, especially the senior PhD students who are experts in their dissertation research areas. A weekly meeting should be scheduled for the group in which problems encountered in the research are discussed or individuals take turns presenting the progress of their projects. During each meeting, the importance of open discussion on scientific issues must be emphasized. Thus, opinions are encouraged, debated, and rejected or accepted. Students are encouraged to listen to and analyze other points of view. In addition to training of this thought process, the meeting also helps identify the strengths and weakness of each individual. As the subject of research expands over time, the group?s and, thus, the faculty?s research experience broadens. With this approach, companies can get the quick answer they desire from expert research experience and the faculty can engage in meaningful applied and basic research that is most relevant to routine mine operations. The end result is that companies will have a high regard for academic mining research.

Jan 1, 2009

By David Baughman, Steven Axen, Ray V. Huff, Donald H. Davidson

Introduction In situ leaching (ISL) is an alternative method of mining uranium from deposits that are low-grade, deeplying, and water-saturated. ISL recovers uranium by transporting fluids through rock rather than by moving rock, a concept the Chinese developed over 2000 years ago for water production. This technique eventually evolved into production systems for oil, gas, sulfur, and salt. More recently, in situ methods have been developed to produce shale oil, gasified coal, geothermal energy, uranium, and copper. ISL uranium operations began in the early 1960s with Sabine Production Co. in south Texas. About the same time, Utah Construction and Mining Co. (Anderson and Richie, 1968) started similar operations in Wyoming's Shirley Basin. During the 1970s, six commercial operations were started in south Texas, (USBM, 1978) and a number of pilot operations were in various stages of development in Colorado, Wyoming, and New Mexico. This paper reviews some of the technical and economic aspects of the ISL process and briefly discusses key subsurface engineering functions as¬sociated with well pattern design and operation. While flow characteristics of a deposit are of prime importance, the following information is also needed: Depth, ore grade, total contained metal, ore thickness, flow conductivity (permeability), void space in rock (porosity), mineral type and distribution, natural groundwater flow, and structural features. Solvent selection, which is important to the economic success of the operation, takes these factors into account: Composition, rate of metal solubilization, interaction with gangue minerals, impact on rock permeability, impact on materials of construction, trace metal solubilization, cost, availability, and handling problems. Overview of ISL An ISL operation consists of these functions (Fig. 1): 1. Chemicals to dissolve and maintain uranium in solution are prepared at the surface extraction facility. 2. A set of injection wells forces the solvent into rock pores of fractures using pressure in excess of the deposit's hydrostatic pressure. 3. Solvent travels through the rock and reacts with uranium minerals to dissolve them. The solvent usually consists of an oxidant and a complexing agent in an acidic or alkaline medium. 4. A set of production wells creates a low-pressure sump where metal-enriched solution is collected for transport to the surface. 5. The enriched solution is processed to recover uranium and to separate the leaching solution for recycling through the system. The economic performance of an in situ operation may be estimated by integrating these related factors: (1) the flow rate of solution processed through the system, (2) rates of fluid injection and production from wells, (3) the rate of mineral solubilization in the liquid phase, and (4) the volume of rock swept by the fluid. As these factors reveal, ISL involves the technical disciplines of petroleum engineering, ore deposit geology, and hydrometallurgical processing. Wellfield Design Just as mineral engineers use drillhole information to plan a conventional mine, in situ engineers use similar information to design a well field. A thorough knowledge of deposit geology and reservoir properties is required. Early application of pressure transient testing, such as

Jan 2, 1980

In June, 1,334 underground construction and tunneling professionals gathered in Toronto, Ontario for the 2007 Rapid Excavation and Tunneling Conference (RETC). This biennial event, sponsored by SME, is one of the global underground construction industry?s major events. And this year?s RETC was the first one that included the new Underground Construction Association. [ ] (UCA) of SME. In addition, the conference?s exhibit attracted 125 equipment and service providers. The next Rapid Excavation and Tunneling Conference is set for June 14-17, 2009 at Caesar?s Palace, Las Vegas, NV.

Jan 1, 2007

By D. J. Pandelis, W. J. Schlittler

Auxiliary Equipment pumping systems to support primary, secondary and regrind grinding circuits will be the primary focus of this paper. Every grinding system is unique and requires special design considerations for proper application of pumps to transport mill discharge. To satisfy the majority of applications, a new series of pumps has been developed by Svedala, known as World Class Pumps. Selection of these newly developed pumps for each type of grinding circuit will be presented. Specific components of selection are materials of construction, piping system, classification method, material characteristics and slurry characteristics. Both horizontal and vertical pump applications will be reviewed with emphasis on rules of pump piping and sump design.

Jan 1, 1999

By D. R. Wilburn

This summary of international mineral exploration activities for the year 2005 draws upon available information from literature, industry and U.S. Geological Survey (USGS) specialists. It provides data on exploration budgets by global region and mineral commodity and identifies significant mineral discoveries and exploration target areas. It also discusses government programs affecting the mineral exploration industry and presents analysis of the mineral industry based on these data. Two types of information are reported and analyzed in this annual review of international exploration for the year 2005. They include budgetary statistics provided by Metals Economics Group (MEG) and information on regional and site-specific exploration activities in 2005 compiled by the USGS.

Jan 1, 2006

By Chee Theng

"Mining professionals are a resilient lot. Sure, copper prices are dismal, permitting processes seem interminable and the top mining companies are shedding jobs like a Shetland sheepdog sheds hair. All the more reason to hone technical skills, reconnect with old contacts and get one’s finger on the pulse of the industry.More than 400 did just that in the balmy sunshine and among the saguaro cactus of the Tucson venue of the SME Arizona Conference.Giving the keynote speech was Patrick Merrin, vice president at Hudbay Minerals (see box), while the luncheon speaker was University Distinguished Professor Mary Poulton, director of the Lowell Institute for Mineral Resources at The University of Arizona.“Attendance was great, especially given the copper price,” said Ta Li, vice president of business development at Tetra Tech and 2001 SME President. “The luncheon speaker was one of the better ones in recent years. Her talk contained a lot of fresh ideas, and practical versus theoretical concepts.”Talk about values, not economicsPraise was unanimous for Poulton, who gave a thought-provoking talk on “The New Face of Mining: The Culture Change for Compatible Mining.” Corporate social responsibility has been embraced by the metals mining industry, and it’s being done right, she said. “So why do we have more conflict? Why are there more protests? Why does permitting take longer and longer?” Poulton made a case for an approach based on compatible, rather than sustainable, mining to present a new face of mining that can be compatible with communities, cultures and the environment, and still be profitable. When the mining industry starts to talk about compatibility between what it is doing and what “me,” as the consumer, wants, what “we,” as citizens of a community, want, and what’s good for the “world,” we’re going to see the next culture change happen, she concluded."

Jan 1, 2015