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From Sept. 22-24, the Las Vegas Convention Center will be home to MinExpo 2008, the world?s largest mining equipment show that comes along once every four years. Sponsored by the National Mining Association (NMA), this year?s show is on pace to be the largest ever. Nearly 1,300 exhibitors have purchased nearly 55,700 hm2 (600,000 sq ft) of booth space. At the center of it all will be some of the most impressive mining equipment that the industry has to offer. And in the shadows of the massive haul trucks, drill rigs and bulldozers, attendees will be able to see the latest and greatest products including hand tools; the latest in automation and robotics; safety and communications equipment; longwall mining equipment; engines and parts; materials handling and processing equipment and services; pollution control equipment; reclamation equipment and services; computer applications; consulting and financial services and more. While many companies will be on hand to display the tried and true, there will also be plenty of new things to see. ?We anticipate that a whole range of new products will be introduced at the show,? the NMA said of the show that has been called the world?s richest deposit of mining technology, services and products. In addition to the show that will take place in Center Hall and North Hall of the Las Vegas Convention Center, MinExpo 2008 includes a conference program with 20 educational sessions that will tackle the most timely and pressing issues affecting the mining industry. Many of the industry?s top professionals will lead the discussions.

Jan 1, 2008

By Cary Hirner

The Metropolitan Water Reclamation District of Greater Chicago (District) is in the final phase of completing the Calumet System component of the Tunnel and Reservoir Plan (TARP) by bringing the Thornton Composite Reservoir online by 2014. The Thornton Composite Reservoir will provide nearly 30 billion liters (7.9 billion gallons) of additional storage for minimization of combined sewer overflows(CSO) and flooding in the Chicago metropolitan area. The project requires that the existing 6.7 m (22 ft) diameter Thorn Creek tunnel conveying overbank flood flows is re-routed and connected to the Thornton Composite Reservoir. This paper presents the components of the Thornton Composite Reservoir and specifically the detailed evaluation of a drill-blast tunnel. Other project features include an access shaft, control gate, energy dissipating structure, bulkheads, and live tunnel connection. The construction contract will be procured in late 2009.

By D. Tao

Reverse cationic flotation is the most widely utilized flotation method for concentrating iron ore. In this process, quartz is often floated with ether amines (R?(OCH2)3?NH2) partially neutralized with acetic acid. However, it is well known that the cationic flotation of quartz does not work well if a certain amount of slime is present in the ore slurry. To improve flotation performance, starch is often added to the flotation feed to selectively flocculate and depress the iron minerals and sodium silicate is used to disperse the silica gangue. The present study was conducted to improve the efficiency of iron ore flotation by the use of a new type of depressant for clay and iron minerals, Georgia Pacific (GP) clay binder. The GP clay binder minimizes slime adsorption on quartz and hematite particles by agglomerating clay particles to reduce their surface area. It also helps depress hematite flotation due to its unique chelating action on iron ions. The results from this study show that the GP clay binder is an effective depressant in iron ore flotation. When it was used as a substitute for corn starch, it increased concentrate grade from 60.78% to 67.67% and increased iron recovery from 71.96% to 72.90%. The combined use of GP clay binder with corn starch produced even better flotation performance, increasing iron recovery to 78.15%, while the concentrate grade remained stable at 67.08%. Keywords: Georgia Pacific clay binder, Iron ore flotation, Flotation efficiency

Jan 1, 2010

By R. K. Jade

Although several studies in combining and bifurcating flows in two-way junctions and splits are reported, deviations persist in the estimated shock loss coefficients (SLCs). Due to their complex nature, more work has to be done to be able to correctly predict flow losses at these locations. In two-way splits, the flow at bifurcation is known to be characterized mainly by two recirculating zones in the downstream branches, whereas, in a junction one recirculating zone is observed immediately downstream of the main branch. The relative flow rate in the branches (quantity ratios) is treated as the only parameter defining the losses at these locations. However, the effect of wall roughness, if any, on SLCs becomes important for mine ventilation. This paper presents the critical determinants of shock losses at splits and junctions at varying quantity ratios. The flow at 90º split and junction was examined both experimentally and numerically for Reynolds number in the range of 1.0×104 to 1.6×105. With a well designed laboratory setup, using precision instruments, velocity and pressure measurements were carried out, by using two scales of wall roughness. 3D numerical simulations for these experiments were conducted by using ANSYS CFX modeling tool. CFD simulations yielded results that are reasonably close to experiments, providing high degree of satisfaction in numerically predicting losses across the splits and junctions. However, comparisons of these numerical simulation results with existing literature standards showed significant under-estimation of shock losses by the standard literature by as much as 50%. A clear rise in the magnitude of shock losses was noted in both the approaches, with increased wall roughness. Based on the current studies, predictor equations incorporating quantity ratios are developed for accurate estimation of shock losses. Further investigations on roughness are needed, before one is able to incorporate wall roughness into the prediction of SLC.

Jan 1, 2009

By Paul C. Schmall, Lucian P. Spiteri, Arthur B. Corwin

Moving groundwater is generally recognized as the most adversarial condition for ground freezing. Moving groundwater can occur due to natural or man-induced groundwater flow, but either way may result in freeze formation difficulties. History has shown that if the condition goes undetected, catastrophic failure of the frozen shaft or excavation can occur. The success of ground freezing under potentially flowing groundwater conditions depends on an evaluation of the likelihood for this condition; an accurate and early diagnosis, with a careful evaluation of freeze pipe temperatures and piezometer water levels; and timely reaction to mitigate the possible delays. Successful remedial measures have included the reduction of ground permeability by modifying the soil properties between the freeze pipes with various kinds of grouting, or increasing the freezing effect by adding freeze pipes and/or the use of liquid nitrogen as the freezing agent.

Jan 1, 2007

By Raymond W. Henn

The 31th annual short course ?Grouting Fundamentals and Current Practice? was held at the Colorado School of Mines, in Golden, CO June 7-11, 2010. The field demonstration portion of the course was conducted June 10 at wlh Construction Co.?s yard in Denver, CO. The full-scale field demonstration presents many types of drilling and grouting equipment in operation as well as numerous grouting methods performed under various field conditions.

Jan 1, 2010

By Shamim A. Dar, & Samsuddin Khan, & K. F. Khan, Mohd Shuaib

The Late Paleocene–Middle Eocene phosphate nodules of Solan District of Himachal Pradesh belong to green facies of Subathu Formation of Sirmur group. Field observations indicate sporadic distribution of phosphatic nodules in the yellow brown to rusty brown, buff-colored bleach shales. Phosphatic nodules are dull earthy to dark grayish in color and break with sharp and conchoidal surfaces. Studies of phosphatic nodules using petrological microscope, X-ray diffractometry, and scanning electron microscopy (SEM) attached with energy dispersive X-ray (EDX) reveal that cryptocrystalline apatite (fluorapatite) is the dominant phosphate mineral. Silt sized silica is the dominant gangue, whereas pyrite and muscovite are present as minor gangue. The phosphate minerals occur as oolites, pellets, and cryptocrystalline apatite in the groundmass. Silica veins form a network replacing the original phosphatic matrix. Brown to brownish black color may be attributed by the organic matter in the phosphatic nodules. Completely phosphatized radiolaria and partially pyritized planktonic foraminifera are observed. There is corroboration of organic matter in the form of microbial filaments in the groundmass of apatite. The findings in the present investigation indicate that the different forms of the minerals, their texture, and distribution in the phosphatic nodules might be due to environmental vicissitudes in oxidizing to reducing conditions followed by replacement processes. Presence of microbial filaments may be due to the active role of microorganisms during the formation of these phosphatic nodules.

By Shamim A. Dar, Mohd Shuaib, K. F. Khan, Samsuddin Khan

The Late Paleocene–Middle Eocene phosphate nodules of Solan District of Himachal Pradesh belong to green facies of Subathu Formation of Sirmur group. Field observations indicate sporadic distribution of phosphatic nodules in the yellow brown to rusty brown, buff-colored bleach shales. Phosphatic nodules are dull earthy to dark grayish in color and break with sharp and conchoidal surfaces. Studies of phosphatic nodules using petrological microscope, X-ray diffractometry, and scanning electron microscopy (SEM) attached with energy dispersive X-ray (EDX) reveal that cryptocrystalline apatite (fluorapatite) is the dominant phosphate mineral. Silt sized silica is the dominant gangue, whereas pyrite and muscovite are present as minor gangue. The phosphate minerals occur as oolites, pellets, and cryptocrystalline apatite in the groundmass. Silica veins form a network replacing the original phosphatic matrix. Brown to brownish black color may be attributed by the organic matter in the phosphatic nodules. Completely phosphatized radiolaria and partially pyritized planktonic foraminifera are observed. There is corroboration of organic matter in the form of microbial filaments in the groundmass of apatite. The findings in the present investigation indicate that the different forms of the minerals, their texture, and distribution in the phosphatic nodules might be due to environmental vicissitudes in oxidizing to reducing conditions followed by replacement processes. Presence of microbial filaments may be due to the active role of microorganisms during the formation of these phosphatic nodules.

By J. J. Sammarco

Computer-aided control of a mining machine pl aces its operator in a safe, remote location, thus reducing health and safety risks, Sensing systems that provide machine position (xy coordinate) and heading (yaw), are extremely useful in aiding remote positioning of mining machines. The U. S. Bureau of Mines has developed two sensing systems for position and heading information: A scanning laser system based on the Lasernet sensor and a mechanical position and heading system based on linear-position transducers. The Bureau is also investigating a system from Honeywell, the modular azimuth and positioning system that employs ring-laser gyroscopes. This paper presents a brief background and status of these sensing systems as applied to the remote positioning tasks of a continuous mining machine. Included are field test results of each system operating in a room-and-pillar research section at a cooperating mine in West Virginia.

Jan 1, 1992

By Ning Wang, Tengfei Guo, Wanyan Li, Hanjie Wen, Hannian Gu, Zehai Li

Bauxite residue (red mud) is an alkaline waste derived from the industrial process for extraction of alumina from bauxite ore. Some bauxite residues contain considerable concentrations of critical metals, for example, rare earth elements. Lithium in red mud was also reported as a potential resource. In the current study, a Li-rich red mud was leached using acetic acid to investigate the leaching behavior of lithium followed by neutralizing with hydrochloric or oxalic acid. By neutralizing red mud using diluted hydrochloric acid (0.01 mol/L), 58.04–60.27% of lithium was leached using 25% acetic acid at 95 °C for 60 min. In the meantime, more than 95% of sodium and 85% of calcium were also dissolved in the leachate solution. While oxalic acid (0.5 mol/L) was used to neutralize red mud prior to acetic acid leaching, lithium performed lower leaching efficiencies (42.41–46.88%) in comparison of using of hydrochloric acid–neutralized red mud. Nevertheless, these leaching efficiencies of lithium were close to that of calcium and much higher than those of sodium under the condition. In this study, 25% (v/v) of acetic acid, at 85 °C for 60 min, was demonstrated as optimum conditions for lithium extraction from oxalic acid–neutralized red mud using acetic acid. The results would be useful and of interest for lithium recovery and purification from red mud.

By Mahiyar Nasarwanji, Jonathan K. Hrica, Jonisha P. Pollard, Lydia M. Kocher, Brianna M. Eiter

Within the metal/nonmetal mining sector, fall-related incidents account for a large proportion of fatal and non-fatal injuries. However, the events and contributing factors leading up to these incidents have not been fully investigated. To help provide a clearer picture of these factors, an analysis of imminent danger orders issued by the Mine Safety and Health Administration (MSHA) between 2010 and 2017 at both surface and underground metal/nonmetal mine sites revealed that most orders are associated with fall risks. Of these cases, 84% involved the workers not using fall protection, fall protection not being provided, or the improper use of fall protection. Fall risks for workers most frequently occurred when standing on mobile equipment, performing maintenance and repairs on plant equipment, or working near highwalls. In most cases, a single, basic, corrective action (e.g., using fall protection) would have allowed workers to perform the task safely. Overall, these findings suggest that a systematic approach is needed to identify, eliminate, and prevent imminent danger situations. Furthermore, to protect mineworkers from falls from height, frequently performed tasks requiring fall protection should be redesigned to eliminate the reliance on personal fall protection.

By M. Javier

Mining is most vital to our civilization. The current model of extraction technologies was designed without an expiration date and therefore generates environmental effects that are severe. Mining results-effects have been traditionally accepted and promoted around the world since Agricola described mining. Mining’s extractive technology is outmoded and standardized and inflicts negative results-effects on nature. Those results are liabilities dimensioned in legacy and type of nature able to provide to the next generation. In order to design, build, and transform mining effectively we must ask: What is the vision of mining? Mining has exhausted its antiquated mindset of over 200 years. Now it merely pilots us into crisis. The challenge today is to resolve the socio-environmental conflicts globally with a radical transformation of the mining business at its core. This paper illustrates that old mindsets must be radically updated or the concept of mining will continue to be trapped. Changing the mindset will enable discourse toward a new destiny. These changes will change mining for the better. We are able to evolve and get different results than in the past by pursuing a new legacy to live in harmony with nature for many more years. INTRODUCTION Minerals are supported by the law of conservation of mass. They have the unique characteristics of being finite, exhaustible, unsustainable, and have an unlimited recycling. Minerals are also hard to find because we have explored and virtually exhausted the whole crust of this planet. Orebodies that used to be considered world class are almost exhausted. In the short-term, it would be almost impossible to find new world class orebodies unless they could be extracted from the ocean, the moon or other planets like Mars. Mining is designed to extract minerals for profit and to keep civilizations functioning. Subsequently, mining has a social issue that is an economic issue. Thus, mining must be seen as a real and urgent subject matter that must be protected in thought and in fact. The actual mining extractive technologies produce disequilibrium in nature that has unknowable effects in the course of time. History is filled with the negative consequences to nature due to the model of mining. The evidence of these effects from mining’s model is apparent in repetitive liabilities around the world. The effects negatively impact nature without any consideration to how these impacts will manifest themselves in the future. This model of mining is widespread and extolled in every corner of the planet because it is old and familiar and although wasteful and outdated, we do not want to expend financial resources from profit or elsewhere to explore newer ideas, methods, or technologies that would help us keep a sustainable harmony between extraction and nature. We need a new vision for mining today and to explore in what way academia can and must play a social role in the teaching of mining methods. We need to question why we continue to support the old model of mining and to ask ourselves what prevents us from updating and modernizing the method of mining to meet the current needs not just of civilization but the urgent needs to undo some of the damage to the earth. This paper hopes to develop a method to change our minds about how we conduct the business of mining in order to control the destiny of it.

Jan 1, 2019

By Thomas Kuhn, Carsten Ruehlemann, Christina Heller, Anna Wegorzewski

The commercial extraction of metals from manganese nodules on an industrial scale requires more than 50% of the investment necessary to realize manganese nodule mining. This is mainly due to the fact that a completely new metallurgical processing scheme for the extraction of both base metals (Ni, Cu, Co) and high-tech metals (Mo, Li, Ga) has to be developed and upgraded to industrial scale. There are a number of conventional processing technologies that combine hydro- and pyro-metallurgical approaches such as the INCO and CUPRION processes which have been developed in the 1970s and 1980s. Today, new approaches based on selective leaching with chelating agents and bioleaching try to minimize energy consumption and waste production. All of these extraction methods require knowledge how the metals are structurally bound in the manganese oxides. In this contribution we will review the current knowledge about the mineralogy of iron and manganese minerals in the different marine oxide deposits, present our results, and discuss the possible consequences for metal extraction.

Sep 1, 2014

By Don Hickey

The MTA in conjunction with LIRR, are in the process of expanding one of the largest commuter railroads in the country, with over 260,000 passengers a day. The LIRR, which provides 700 passenger trains every 24 hours, can?t continue on the present growth course as a joint tenant in Penn Station with Amtrak and NJT. For this reason, in conjunction with the fact that over 53% of LIRR?s current riders into Penn Station are ultimately bound for the East Side of Manhattan opening, have created the need for the expansion of the LIRR. The complete expansion will cost approximately 6.3 billion dollars and all of the contracts are to be completed by 2013.

By Vladimir Admek, Paul W. Jeran, Michael A. Trevits

It has' been found that lithological conditions over the Pittsburgh Coal bed cause the subsidence coefficient to vary within the area of the subsidence trough. This precludes the use of European developed predictive models, which are based upon a constant subsidence coefficient. Regression analysis of the distribution of subsidence coefficients from 11 Bureau of Mines, U.S. Department of the Interior, longwall panel studies on the location relative to the edge of the panel has yielded a third degree polynomial equation. This equation has been incorporated into a BASIC computer program for use on a personal computer that allows users with no previous knowledge of the theory of subsidence to predict vertical movements over typical longwall panels in the Northern Appa1achian Coal Basin.

Jan 1, 1986

By S. A. Richards

Business planning in the coal' industry revolves around the production and quality forecast. It is difficult to accurately estimate costs and revenues until the production forecast is made. At mines where production comes from multiple sections, quality is tied to each section's production. Blending becomes a part of the planning process. In order to respond to rapidly changing business climate, a reliable program is needed to accurately forecast the effects of changes in key parameters affecting the production. This paper discusses an efficient, intuitive, and economical approach to underground coal mine planning program which uses a PC-based relational database as the programming platform to forecast production and quality. The program was developed at a major coal company. The relational nature of the production planning data, the programming algorithm, and the underlying principles are discussed in this paper.

Jan 1, 1994

By J. Drelich, M. Pawlik

An improved experimental procedure to measure contact angle has been consolidated with coal surface preparation involving polishing with abrasive paper, alumina powder, and a cloth, followed by ultrasonic and mechanical cleaning. Specifically, the captive-bubble measuring technique has been compared with the sessile-drop technique and the former has been recommended for the examination of the hydrophobic properties of coal surfaces. Results of the research program, which is currently under way, on the examination of the effect of the nature, amount, size, and distribution of mineral inclusions in coal, on its wettability are briefly reviewed.

Jan 1, 1999

By Arthur D. Silber

The economic success and growth of any metropolitan region depends on mobility. Today, mobility between New Jersey and New York is threatened by a transportation system that cannot meet 21st century travel demands. The transportation bottleneck created by the Hudson River threatens the viability of one of the world?s great centers of commerce and culture. Fortunately, there is a solution: The Access to the Region?s Core Mass Transit Tunnel. The US$8.7-billion Mass Tran-sit Tunnel?s (MTT) new two-track line will double commuter rail capacity under the Hudson and create a new, state-of-the-art cavern station in Midtown Manhattan, with wide platforms, high-speed escalators and other features to improve riders? travel experience. The capacity and other benefits of the MTT project will launch a new era of prosperity for the region, just as the Pennsylvania Railroad did almost 100 years ago when it built the existing two, single-track rail tunnels that now form the sole commuter rail link between New Jersey and New York. The existing tunnels run from North Bergen, NJ, under the Hudson River to Pennsylvania Station at 33rd Street in Manhattan. Construction on the MTT, the largest public works project in the United States, is scheduled to start this year and continue through 2017. The MTT is ready to go to construction thanks to a major commitment of financial, engineering, project management and other resources from NJ TRAN-SIT, New Jersey?s statewide mass transit agency, and the Port Authority of New York and New Jersey, a bistate agency that operates the Holland and Lincoln tunnels, the George Washington Bridge and other major transportation facilities in New York and New Jersey. The project is also strongly supported by the state governments of New York and New Jersey, as well as that of New York City. The MTT is New Jersey Governor Jon Corzine?s number one transportation priority.

Jan 1, 2009

By J. Kretschmann

?We have constructed a world in which the potential for high-tech catastrophe is embedded in the fabric of day-to-day life.? (Malcolm Gladwell) The mining industry is a crucial provider for virtually every person?s needs and thus indispensable. Yet, mining is a complex and risky business: plenty of high risk factors can occur and severely affect nature and the miner?s life and health. Especially for small and medium enterprises (SME) risks may also threaten the economic existence of the company. The responsible and sustainable management of a company should thus be based upon the systematic finding and handling of risks or briefly upon an efficient risk management system. Why do we need risk management? Because nobody is perfect and we make mistakes in the normal course of operation.

Jan 1, 2011

Despite the current economic downturn that is now decimating iron ore production, Minnesota?s mining operators remain optimistic about the long-term prospects for the industry. Reflecting this optimism, the development of several new mining projects continues in the state. The future of mining in Minnesota was the featured topic at the combined 82nd Annual Minnesota Section of SME Meeting and 70th Annual University of Minnesota Mining Symposium. More than 500 mining industry professionals, including engineers, executives, mining managers and equipment suppliers from the around the world, attended the meeting, which was held April 14 and 15, 2009, in Duluth, MN. The combined meeting featured a keynote session with three distinguished speakers plus a panel discussion by representatives from several of Minnesota?s taconite producers. The keynote speakers were Curtis Clark, president and chief operating officer, Behr Dolbear, who gave a presentation on the ?State of the Mining Industry.? Phil Newman, chief operating officer, CRU Strategies, spoke about challenges facing the mining industry and James A. Skurla, acting director, Bureau of Business and Economic Research, Labovitz School of Business and Economics, University of Minnesota Duluth, discussed the importance of mining to northeastern Minnesota?s economy. The taconite producers panel discussion included Jonathan Holmes, vice president and operations manager, ArcelorMittal; Ed Latendresse, vice president and general manger, Hibbing Taconite; John Tuomi, vice president operations services, United Taconite and Mike Mliner, vice president and general manager, Northshore Mining. The mangers provided updates on their respective operation The meeting included concurrent technical papers sessions on mining, processing, environmental and nonferrous mining. The sessions included technical papers that provided information on the status of a number of new mining projects in the state. The conference also offered a SME short course titled ?The basics of iron mining.? A tradeshow that featured about 100 companies and organizations offering products and services to Minnesota?s mining industry ran in conjunction to the conference. It was estimated that more than 900 people, including conference registrants and special invited guests of the vendors, attended the tradeshow opening reception. This was the largest trade show in many years. The Minnesota Section of SME also held its annual business meeting during the conference.

Jan 1, 2009