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The following is a summary of some of the companies that were exhibiting their products and services at MINExpo INTERNATIONAL 2000. Atlas Copco develops, manufactures and markets rock drilling tools, tunneling and mining equipment, and surface and geotechnical drilling equipment. The company provides a line of drilling products, including production drilling rigs, rock reinforcement bolts and rock drills. Atlas Copco’s Boomer is a series of high-capacity drill rigs that provides economy, production capacity and reliability

Jan 1, 2000

By Yuqi Zhao, Zhiyong Lin, Leiting Shen, Hongyang Wang

Gibbsite-type bauxite is the main material for alumina extraction by Bayer process globally, while the iron in red mud is difficult to use for the high alumina content. Therefore, the efficient separation of iron and alumina is the premise for the resource utilization of red mud. In this work, the separation of iron and alumina in red mud containing 47.45% Fe and 11.58% Al2O3 was studied through reduction roasting followed by magnetic separation. The analysis methods of XRD, VSM, SEM, and EDS were used to investigate the phase transformation of red mud during reduction roasting. Results show that hematite can be firstly reduced into magnetite, and alumogoethite into magnetite and alumina. Then, the magnetite reduction undergoes the process of Fe3O4→FeO→Fe, while alumina can react with FeO to form hercynite. The hercynite is ultimately reduced into metallic iron and alumina at elevated temperature. The specific saturation magnetization of reduced product is closely related to its main minerals, that is, the specific saturation magnetization of magnetite and metallic iron is higher than that of wustite and hercynite. The mass ratio of Fe to Al2O3 in magnetic concentrate increases with roasting temperature, from 4.55 at 600 °C to 10.27 at 1200 °C. Therefore, efficient separation of iron and alumina in red mud could be achieved through deep reduction-magnetic separation.

May 2, 2024

By Hernan Fernandez, Khalid Saif F S Al- Khayareen, Volkan Salepciler, Jacek B. Stypulkowski

Wakrah and Wukair Drainage Tunnel, WWDT is 13 km long with a 4.5 m ID sewer water tunnel about 50 to 60 m below ground surface. Integral to the project are several adits with provisions for future connections as well as four work shafts, four intermediate access shafts, ancillary hydraulic structures, and an Odor Control Facility. The shaft depths range from 50 to 60 m. The project is constructed in aggressive ground with aggressive ground water. The construction activities require years of pumping and disposal of the ground water during tunneling operations as well as construction of permanent structures in shafts. Grouting of the corrosive rock mass in corrosive groundwater for the WWDT has been described in detail.

Jun 23, 2024

By Marco Sonnenschein

As time is costly, engineering companies have developed methods, procedures and mechanical equipment to tunnel faster. But the best excavation method will not be able to cope with the time pressure if there is not a reliable backup system. Therefore, the application of belt conveyors for tunnel boring machine (TBM) drives as well as for drill-and-blast driven tunnels assure a quick and smooth removal of excavated soil in order to enhance the efficiency of the tunneling equipment. During the last 10 years, belt conveyor systems have achieved ?state-of-the-art? levels and have become the first choice for muck removal systems in both TBM and drill-and-blast driven tunnels. Because time has become such a key criterion in tunneling projects, it is essential that all equipment is operated so as to derive optimum efficiency and minimize costs. Efficiency also means to think about new tasks for existing technologies.

Jan 1, 2012

By J-P Strydom, J P. Z, S. Schafrik, M. Beck, Z. Agioutantis

Developing a method to accurately determine the weight and distribution of the load within a shuttle car bed eliminates the need for manual activation of the flight chain. Accordingly, this experimental study characterized the thermo-mechanical response of two unique load cells in force shunt, implemented as an engineering control to quantify load position and distribution without human intervention. The influence of environmental and installation conditions on the measurement accuracy was quantified and determined to be indirectly dependent on the characteristics of the material load cells that are mounted to.

Feb 22, 2026

By AK Raina

Blasting is used in mining and civil excavations to break the rockmass for ore production or creation of space. One of the disadvantages of the method is that it causes breakage beyond the proposed excavation lines. Pre-split is used to control such breakage in rockmass. This paper introduces the use of digital image analysis technique (DIAT) to measure rock breakage and half cast factor (HCF%). A new factor, undamaged area (AUD%), is introduced to improve the prediction, owing to the shortcomings of the HCF%. A comparison of significant data of AUD% and HCF% showed that HCF% has a lacuna of overpredicting, whereas AUD% can be used effectively to address the issue. Artificial neural networks are used to solve the complexity of multiple variables involved in predictions and to ascertain the importance and sensitivity of such variables in prediction regimes. This method will help users to evolve blast-induced damage objectively. A comprehensive scheme of things for future developments is included, which can be helpful to researchers in defining their research in this area.

By Shigeru Nishitake

The Earth Pressure Balanced (EPB) shields designed by Mitsubishi Heavy Industries, Ltd., are recently more enthusiastically accepted by tunnel boring specialists. This company having built 1,000 tunnel shields utilizes its vast experience to resolve the problem to excavate through big boulders scattered in rather soft alluvial soil. Several types of EPB shields which can cope with large size boulders are described. Such shields are equipped with both drag bits and rolling disc cutters on the cutterheads. Previously removal of boulders has presented safety problems for workers while in the muck chamber, or venturing in front of the shield. This report describes the problem and how the equipment was modified to deal with the problem.

Jan 1, 1987

China’s vibrant economic growth is built on coal, the source of two thirds of the country’s electricity. Over 95 percent of China’s coal is mined underground with the average mining depth at 410 m and in-creasing at 10 m per year; today, the deepest Chinese coal mines have exceeded 1,000 m. With increasing mining depths, there are greater challenges including increased methane emissions and spontaneous combustion. According to the government, nearly half of China’s coal mines are classified as gassy (with specific gas content at least 10 m3/mt). Coalbed methane (CBM) is a clean energy source. However, only a small percentage of the methane is captured, and the rest is vented directly to the atmosphere. This paper describes China’s CBM resource, its production and utilization.

Jan 1, 2006

MINExpo International is billed as the largest exposition for the mining and mineral processing industry. And the 2012 edition, scheduled for Sept. 24-26 in Las Vegas, NV, is no exception. Put on by the National Mining Association (NMA), attendance at this year?s show is expected to be significantly more than the 38,500 who attended the last MINExpo in 2008. The exhibit will also be quite a bit larger in 2012 than it was at the previous MINExpo. More than 1,800 companies, representing more than 30 countries, will fill the Las Vegas Convention Center. The more than 850,000 sq ft of exhibit space will include the North and Central halls as well as South Halls Nos. 3 and 4. And the Silver Lot outside of the front door, under construction in 2008, will be filled with more exhibitors. The 2008 show attracted about 1,220 exhibitors occupying more than 600,000 sq ft of exhibit space.

Jan 1, 2012

By Axel Nitschke, Josef Arnold

Bochum’s Underground Lot 306 was characterised by a confined site and unique tunnelling methods. A highly mechanized construction concept was developed to achieve high progress rates. Bespoke backup systems for muck disposal and material supply were used. For the first time in suburban tunnelling, wet shotcrete, batched onsite, was applied. A three-storey underground car park had to be undermined with only1.5 m of overburden and had to be lifted several times by “compensation grout in.” An existing operational two-lane metro tunnel was enlarged without any major impact on train operation.

Jan 1, 2005

By NEHA PANDEY, Sunil Kumar Tripathy, ARIJIT BISWAS

Due to the growing market of Electric Vehicles (EVs), there is a rise in battery demand. Nickel can be used as a potential element in cathode for lithium-ion batteries. Nickel can provide thermal stability, high energy density, and conductivity in cathodes of lithium-ion batteries. Low-grade chromite overburden from Sukinda mines contains less than 1 wt% of nickel, which can be utilized to extract nickel. Recovery of nickel from such low-grade overburden can help in value addition. The present study provides deeper insight into the aspects of extraction of nickel product derivatives (NPDs), mainly mixed hydroxide product (MHP), through the hydrometallurgical route. The current study focuses on extracting nickel and cobalt from a mine overburden with 0.41% nickel with major silicate gangue. MHP can be processed further for nickel sulfate production, a potential raw material for cathodes in EV batteries. The study discusses a process flowsheet to recover nickel and cobalt from overburden through atmospheric leaching with pre-calcination. It is observed that the step of pre-calcination improves the effective recovery of nickel from overburden. The leaching reactions are effective at a temperature of 90 °C and 1 atmosphere pressure. The orthophosphoric acid was used as a lixiviant for the selective recovery of nickel and cobalt from overburden. Recovery of nickel and cobalt obtained at optimum conditions is 84.0% and 39.9%, respectively. The iron impurity in the leachate solution is 1.27%. It is concluded that the process with pre-calcination along with acid leaching is effective for extracting nickel and cobalt at atmospheric pressure.

Dec 28, 2023

By C. J. Bise, D. A. Poukhovski

Two integral components of the 30 CFR 48 training requirements mandated for new miners, newly employed experienced miners, and the annual refresher training of all miners are hazard recognition and prevention of accidents. In these categories, instruction shall include the recognition and avoidance of hazards present in the mine, and a review of accidents and their causes. Unlike instruction preparation for fact-based material, program development for hazard recognition places a particular challenge before safety-training specialists because they are often limited in their ability to adequately gauge the trainees' levels awareness prior to training. Further, they must also assure that the training is relevant, and it is presented in a thought-provoking manner. Computer-based instruction is particularly well suited for assisting trainers in developing hazard- recognition topics because it can be used in pre-training and post-training modes for assessment of training effectiveness, in addition to use as a presentation tool. Therefore, this paper will present a recent approach developed at Penn State to apply this technology for assessment and instruction of accident prevention through hazard recognition, with an application prepared for surface coal mines.

Feb 24, 1997

By Gerhard Lang

"Slurry Microtunneling is a well-established technology building on over 20 years of experience in successful tunnel installations under all kinds of soil conditions across the U.S. and Canada. Recent microtunnel installations prove that initial hesitation, e.g. curved drives, is fading and long-distance pipe jacking projects as well as lake outfalls are being considered. One of the younger technologies is Direct Pipe®, which combines the benefits of HDD and Slurry Microtunneling. It fits exactly into the area where HDD is not feasible or too risky to apply. The paper points out the benefits of the Direct Pipe® technology for owners, engineers and contractors and discusses the latest developments of Slurry Microtunneling for long-distance, curved drives and sea/lake outfalls with wet recovery of the equipment such as on the ‘Keswick Outfall Project’ in Ontario. The first Direct Pipe® installation in the US was executed in August 2010. Since then, another 22 crossings have been carried out amongst a total of more than 60 Direct Pipe® crossings worldwide. INTRODUCTION Pipelines installed underground are indispensable for supplying the growing world population with water, oil, gas and electricity, for removing wastewater and for providing functioning telephone and communications networks. During recent years the limits of trenchless applications have been permanently shifted, leading to higher and more stringent project requirements and consequently new technologies, either as further development of existing methods, or through the development of new methods by incorporating elements of proven technologies. MICROTUNNELING TRENDS IN NORTH AMERICA Slurry Microtunneling has a wider geological application range in comparison to EPB and hard rock Microtunneling. The Slurry MTBM can be equipped with specific cutting wheels to cope with different soil conditions. The most flexible and most often employed type is the mixed soil cutting wheel, which contains a mixture of disc cutters as well as scrapers for varying soil conditions from cohesive soils (clay, silts) to highly permeable soils including sands, gravels and cobbles and even hard ground formations such as rock and boulders. A detailed geotechnical report provides the appropriate data to configure the MTBM and its features to the ground conditions expected. Mixshield or hydroshield (AVN/AVND) MTBMs in particular, can be safely operated with little overburden (~ 3-5 x machine diameter) and minimum risk of frac-out or settlement on the surface. This is especially beneficial in urban areas with sensitive buildings or for river crossings with protected fish habitats."

Jan 1, 2016

By E. A. Domínguez

La Espingarda kaolin deposit was formed by ?in situ? alteration of volcaniclastic rhyolitic rocks belonging to Jurassic Marifil Formation. Three volcanic lithofacies were identified: porphyric biotitic ignimbrites (PBI), a coarse lithic ignimbrite (ILG), a fluidal intrusive rhyolite (RFI), all kaolinized in different degrees. The alteration covers an ellipsoidal area of ~20,000 m2, with its alteration decreasing downwards and disappearing at 8-12 m from the surface. The length to thickness ratio of alteration is 60:1. An erratic silicification was found as small zones (<3 m2) of quartz stockwork. The mineralogy is kaolinite + quartz + feldspars + Fe-oxyhydroxides ± halloysite ± illite and interstratified I/S, although the relative proportions change in each rock type. Due to coarse grain size and high quartz content, natural kaolin is unsuitable for slip cast ceramics, unless beneficiated. Washed ILG kaolin has the best rheological properties and behavior in casting and drying for its mineralogy, particle size distribution, thin texture and surface activity, as well as a certain fusibility and firing kinetics. PBI and RFI kaolins, due to finer texture, smaller grain size, lower surface activity, and higher halloysite amount, have worse slip viscosity and thixotropy that are due also to soluble salts. For the same reason, they have good casting and drying properties, but their purity brings about higher softening temperatures and water absorption. Several parameters are used to discriminate between hypogene or supergene kaolinite genesis. The hydrothermal genesis is mainly sustained by fluid inclusion temperature (150-180ºC) in quartz veinlets, while weathering is supported by deposit morphology, simple mineralogy, kaolinite stable isotopes (d18O ? 18, 13; dD ? ?59; ?85) and paleoclimatic record. It is concluded that a weathering process formed the main alteration with some participation of steam-heated meteoric waters. Neither the contents of Au, Ag, As, Sb, Hg, nor drill data support the existence of any epithermal gold mineralization at the kaolinite bottom.

Jan 1, 2010

By Glen D. Frank, Jeremy P. Theys, Mina M. Shinouda, Gary W. Gilbert

PURPOSE OF THE PROJECT The Big Walnut Augmentation Rickenbacker Interceptor project began in 1995with the preparation of the Scope of Services for the design of the Rickenbacker Interceptor, with service to and around the Rickenbacker Air Force base. The air base was soon to be placed under civilian control through a Port Authority, with an expected influx of businesses and services, requiring increased sanitary service capability. Due to political differences regarding annexation and other issues, the project was placed on hold. In mid 1996 the Scope of Services was rewritten with more emphasis on a tunneling option, but still only addressing the air base and surrounding tributary are a sanitary service requirements. The consultant selection process began in late 1996 with the Request for Statements of Qualifications issued in December. Three firms were selected to furnish proposals based on the revised Scope of Services that now included requirements for hydraulic modeling of the service areas and the Big Walnut Outfall (BWO) and an expanded soil investigation requirement. All three firms were requested to make presentations to the selection committee, with the committee selecting URS Greiner for further consideration and negotiation. A contract was entered into in August of 1997with URS Greiner. The major sub-consultants were Lachel and Associates, Inc., H.R.Gray and Associates and Solar Testing Laboratories, Inc. The project began with geological investigations, preliminary soil borings, well investigations, tributary area evaluations, hydraulic modeling of the BWO system and research into other projects planned for the Rickenbacker airport and surrounding area. The hydraulic modeling of the BWO and the proposed Rickenbacker Interceptor confirmed that the BWO suffered wet weather surcharging and would require augmentation to properly convey the future flows to the Southerly Wastewater Treatment Plant(SWWTP). The project scope expanded to include evaluation of both the Rickenbacker Interceptor and the Big Walnut Augmentation projects. Both projects previously identified in the Capital Improvements Program. The work on the expanded scope for the Big Walnut Augmentation and the Rickenbacker Interceptor began with the evaluation of a parallel 2.75 meter (108") diameter augmentation sewer from SWWTP to S.R. 317and Parsons Avenue, then continuing east along S.R. 317 as the Rickenbacker Interceptor. The parallel 2.75 meter (108") sewer had been planned for in the design of

Jan 1, 2007

By Chikaosa Tanimoto

INTRODUCTION Bratislava is located at the intersection of important traffic routes, including motor-ways, roads, railways, air traffic, trading, and inland waterway with an important harbour. The construction of the D2 Motorway Bratislava, Lamacska cesta Stare grunty was the last missing section of D2 Motorway and its completion linked the Czech Republic through Bratislava to the Hungarian Republic. Traffic was obliged until its completion to use the Lamacska Road and Mlynska Dolina, which were the most heavily trafficked roads in the city. The section of D2 Motorway to be completed in 2006 was 3,300m in length, of which the SITINA Tunnel was approximately half the length. After putting into operation the transit traffic(motorway) and urban traffic was separated. Transit traffic by passing the town was eased. The junctions D2 with Lamacska Road (Harmincova) and Mlynska Dolina also allowed better use of the motorway for the urban traffic The tunnel construction was specified by the features with the highly weathered and thermally altered granitic rock formation with the overburden of Quaternary sediment of 2?4 m thick, very thin overburden, severely controlled deformation limit and environmental protection. The tunnel had to be excavated beneath and nearby the academic complex area and the zoo, where sensitive facilities exist and animals live in. The tunnel consisted of two tunnels (Tunnel A and B) with the length of 1,415 and 1,440 m, respectively. The overburden thickness was in the range from 10?30 m. The standard cross-section and the one with invert arch were 79.5?81.5 m2 and 92.1?93.3 m2. The excavation took 21 months from September 2003 to May 2005. The construction was based on the concept of NATM. The SITINA Tunnel was the third application of NATM in Slovakia, following the BRANKISKO Tunnel (commenced in July 2003) as the first and the HORELICA Tunnel (in October 2004) as the second NATM practice. To protect the surrounding structures and citizens from tunneling operations, seismic monitoring was performed in association with blasting. The allowable limit of blasting vibration was fixed to be under the particle velocity of 15 mm/sec. The tunnel excavation cleared this limit as expected before construction. In driving through the difficult geological situation the excavation work hit 49 faults, and some of them occasionally caused serious face instability. In principle, the rock formation has been affected by the high hydrothermal effect and the resultant clay filing along faults and joints. The auxiliary reinforcement with the 4?8 m long pipe roofing was needed to protect the vicinity of mining face area. This operation extraordinarily required additional works and time which had not been expected before construction.

By K. A. Lewandowski

Binders have been suggested as an aid for agglomeration to improve copper recovery in heap leaching operations. However, it has not been established if the use of binders would negatively affect the solvent extraction process, which is used to purify the pregnant leach solution from the heaps and remove any contaminants. Such negative effects would lead to an increase in processing costs or a decreased in copper production. The controlled studies reported here have shown that some binders (a polyacrylamide and a waste treatment additive) did not interfere with the solvent extraction process. Other binders (a polyvinyl acetate emulsion and tall oil pitch) negatively impacted copper solvent extraction and, therefore, should not be used in copper heap leaching plants.

Jan 1, 2009

By George M. Leonard

Mineral commodities on National Forest System lands contribute to the nation&apos;s well being. Access to these commodities is dependent on public perceptions of the effects of mineral operations on other resources. An outlook is described which the Forest Service believes is essential to the minerals industry if it plans to continue seeking minerals on National Forest and Grasslands.

Jan 1, 1991

By Mark N. Savit

It is indeed a rarity for a non-engineer, let alone a lawyer, to even be considered for a mining-related award, especially where that award is for significant contributions to technical progress in the mining and exploration sectors. So, when I was notified that I had received this award, I struggled for a topic that would meld the legal world that I operate in with the engineering driven world of exploration and extraction. The most exciting part of my job has always been the opportunity to absorb the technical details of the cases I work on and, in effect, translate them for a lay audience. Too often, I have found, lawyers, judges, legislators and yes, even regulators who lack a technical background simply give up trying to understand the details of the very conditions or processes that they are trying to describe and simply repeat phrases told to them by their client or by a retained expert.

Jan 1, 2008

By N. Weidner, V. A. Samaranayake, K. Awuah-Offei, S. Que

"This research sought to facilitate improved stakeholder (community) analysis using discrete choice theory (DCT). The work considered 16 project attributes and four demographic factors. The discrete choice experiment was conducted in Salt Lake City, Utah to illustrate the usefulness of DCT in mining stakeholder analysis. The data was used in discrete choice modeling of individual preferences. The approach answers three important questions for enhanced stakeholder analysis: (1) What are the factors that affect individual preferences? (2) What is the effect of demographics on individual preferences? (3) What is the value of environmental and social impacts to individuals in the community? INTRODUCTION Stakeholder analysis is crucial for effective stakeholder engagement because it is important to identify and characterize stakeholders in order to effectively engage in dialogue with them. This is not only true for all stakeholders but true for characterizing the members of a particular stakeholder. The local community is usually the largest and most diverse single stakeholder group. Also, the local community is perhaps the most important stakeholder group. Thus, analysis of the local community is essential for project management. Conventional mining stakeholder analysis is a three-step process, which involves evaluating: (1) each stakeholder’s view of the project (positive, neutral, or negative); (2) how influential each stakeholder is (high, medium, or low); and (3) how they will be impacted by the project (high, medium, or low) (ICMM, 2012). The results of this evaluation are documented in a stakeholder analysis matrix (Table 1), which is used to classify the stakeholders into three groups: highly influential supporter of the project, neutral about the project, and highly influential opponent of the project. This process can be used to describe groups of stakeholders (e.g. community, non-governmental organizations, etc.) or individuals making up a particular stakeholder group (e.g. members of the local community)."

Jan 1, 2016