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By Christopher J. Bise

INTRODUCTION The transportation of men, supplies, and mined material from an underground operation is the connecting link between the mine plant and the surface plant. Unless the mine is accessed by a drift or adit, some form of hoisting system is necessary for slopes or shafts. This chapter will deal with the selection of wire ropes and hoists, two of the most important consider¬ations when designing a hoisting system for an under¬ground mine. WIRE ROPES General A wire rope is designed to transmit forces longitudi¬nally along its axis. Wire rope is used in a variety of mining applications because of its flexibility, high ten¬sile strength, and dependability. Shaft hoisting ropes and principal slope haulage ropes are usually custom-¬built; however, proper rope selection for slushers, car spotters, etc. should not be overlooked. Wire ropes for shafts and slopes, since they represent the life line for the mines, should be of the very highest quality improved plow steel. This quality is necessary to deal with the conditions of loading, winding, vibration, abrasion, and corrosion. Tables I and 2 display the specifications for the typical wire ropes used for mine haulage applications. The 6 x 19-class haulage rope is used for most hoisting where abrasion is not critical. On the other hand, where abrasion is critical, such as a slope application, 6 X 7-class haulage ropes are preferred. For other mining applications, manufactur¬ers' handbooks should be consulted. Selection The selection of a wire rope for a mining situation consists of simply applying appropriate safety factors to a calculated maximum rope pull and comparing the result to the listed breaking strength of the rope under consideration. Table 3 can be used for determin¬ing the minimum factors of safety for wire ropes. To determine the maximum rope pull, the following quantities must be known: the rope weight in pounds (x), the conveyance weight in pounds (y), and the weight in pounds of the load in the conveyance (z). These values are used to calculate the load due to gravity, the load due to conveyance friction, and the load due to rope friction. When these loads are added together, as shown in Eq. 1, the maximum (static) rope pull (RPS) can be derived:

Jan 1, 1986

By Lawrence Williamson, Randall J. Essex, David P. Field

As part of a $2.2 Billion bridge project that will link Indiana and Kentucky, an interchange project northeast of Louisville will require the mining of a 6-lane tunnel system about 2,000 ft long in order to cross beneath the historic Drumanard Estate. This paper will discuss preliminary engineering that has been undertaken to compare two-bore and three-bore layouts, the planning of an exploratory tunnel facility, and the potential for including a test chamber to investigate the ability of high capacity roadheaders to mine the 22,000 psi limestones.

Jan 1, 2005

By D. Gu

Shaft drilling is one of the most useful methods of driving shafts. This paper describes the application and development of the technique in coal mine construction in China.

Jan 1, 1993

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 E. Giama, A. Macridis, A. M. Papadopoulos

ISO 14031 is an international standard that describes a process for measuring environmental performance evaluation by setting quantitative indicators and providing a structured approach for organizations to follow, independent of location, size, complexity and type of activity. It is not a standard for certification as ISO 14001 is, but it fits into the ISO 14000 series of standards and is intended to assist organizations to apply environmental management systems and obtain environmental evaluation. This case study’s main objective is to identify the interaction between ISO 14031 and ISO 14040-42. ISO 14040-42 is referring to Life Cycle Analysis (LCA) methodology. More specific, LCA is applied (based on the ISO 14040-42 standard) to stone wool’s production, the market dominating thermal insulation material, produced by bauxite and amphibolite. LCA is used as a decision making tool for the development of environmental indicators (based on ISO 14031 guidelines) and for environmental performance evaluation.

Jan 1, 2005

By O. Kangal

Flame retardant materials can be incorporated or applied to products, including plastics and textiles, to increase their resistance to fire. Incorporating a flame retardant in combustible materials and plastics is a common procedure to reduce the risk of fires. Flame retardant applications include interior and exterior woods, structural steel columns, fabrics, open and closed cell foam, pressure treated wood, Formica and all types of fabrics for use in commercial applications as well as residential applications where their fire protection products can save lives and valuables. Huntite and hydromagnesite are amongst the most important flame retardant additives materials. Although various areas of the world have potential huntite and hydromagnesite deposits, their place in industry is not well known, and a detailed field search for their deposits has not yet been conducted. They are active during the starting phase of a fire, in that they prevent the spread of an inner or exterior source of ignition to the flame-retarded material, thereby, preventing, delaying or inhibiting the spread of a fire. Flame-retardants are, therefore, just one element among many in a concept for preventive fire safety. To obtain huntite and hydromagnesite concentrates that are more than 95% pure, which are used in flame retardant industry, flotation tests were conducted on low-quality huntite and hydromagnesite ores.

Jan 1, 2009

By V. K. Paruchuri, J. D. Miller, J. Nalaskowski

The phenomenon of surfactant adsorption at mineral surfaces is of significant importance in many particulate processes ranging from mineral flotation and enhanced oil recovery to pharmaceutics, paint technology and the casting of high quality ceramics. Stability of the dispersions is related not only to the amount of adsorbed surfactant but also to the structure of the adsorbed surfactant molecules at the interface. This structure greatly depends on the type of surfactant and the hydrophobicity or hydrophilicity of the surface. On hydrophobic surfaces surfactants adsorb regardless of surface charge by van der Waals/hydrophobic inter-actions with hydrocarbon chains accommodated at the surface. On the other hand, on hydrophilic surfaces the surfactants adsorb through electrostatic interactions with their polar moiety fixed at the surface. In the latter case, the electric charge of the surface and surfactant plays a crucial role in the surfactant adsorption process. The recently developed soft-contact Atomic Force Microscopy technique has revealed images of adsorbed surfactant structures at various interfaces. The adsorbed structures of a cationic surfactant (CTAB) and an anionic surfactant (SDS) are presented in this work for different concentrations at hydrophobic graphite and hydrophilic mica surfaces. Different types of micellar arrangements have been observed at these surfaces for surfactant concentrations around the critical micelle concentration. The structures are more ordered and well defined at the graphite surface than at the mica surface. These results have been correlated with the hydrophobicity of the surfaces as revealed by contact angle measurements.

Jan 1, 2001

By F. Schreiter

The Ore Mountains in Germany have a history of more than 850 years of underground mining activity. This has created a situation where thousands of old mine shafts and adits are due for rehabilitation. While no long-term stable rehabilitation was executed in previous centuries, those abandoned mine sites which date back to the uranium mining boom from 1945 to 1962 were rehabilitated immediately after mine closure according to state-of-the art technology. Over the years, however, it has become obvious that most of these sites are not long-term stable and thus it has become necessary to rehabilitate them a second time. Technical University Bergakademie Freiberg is carrying out a research project on the optimization of this process. 70 mine site rehabilitation projects, the technology and the materials used have been assessed. A technical guideline for future rehabilitation projects, based on the outcomes of this assessment, is under development with the goal to make it easier, faster and more economical to select and apply suitable designs and construction materials for dams, plugs and other rehabilitation structures in former uranium mines.

Feb 27, 2013

By Steve Kral

The timing was right for SME to celebrate its 50th anniversary in February as a member society of AIME. The mining industry is in the midst of a commodities boom that appears to have legs. Not only is the demand for metals, construction materials and the like increasing in developing nations, but developed nations have also seen the demand for those materials increase at impressive rates. So, in addition to networking and seeing old friends, attendees at the SME Annual Meeting and Exhibit in Denver, CO. Feb. 25-28, had several reasons to enjoy the week — a healthy industry and their society’s landmark anniversary. This annual meeting was held jointly with the Colorado Mining Association’s (CMA) 109th National Western Mining Conference.

Jan 1, 2007

By Les Gutzwiller

Fan applications in the mining industry have changed during the last 70 years. In 1922, J.R. Robinson authored a technical volume entitled Practical Mine Ventilation. At that time, atmospheric control had only recently shifted from natural to mechanical. The large, mechanical draft fans that were used then were centrifugal. The fans ran at low speeds, about300 rpm. Most were steam-engine driven. In the late 1920s and early 1930s, mines became larger, increasing the pressure and volume requirements of the fan equipment. Axial fans were designed to run at much higher speeds (710 to 880 rpm) and were driven by electric motors. They were also smaller and less expensive to install than the cumbersome centrifugal units. However, changes in mining have resulted in progressively higher static-pressure requirements. So centrifugal fans are once again proving to be a good choice.

Jan 1, 1999

By Maurice A. Ponti

The D.C. Water and Sewer Authority is implementing the Anacostia River Projects component of its Long-Term CSO Control Plan, including 21 kilometers of 3.7- to 7-meter-diameter CSO near-surface diversion storage/conveyance structures and flood relief, pressurized-face, soft ground tunnels at a maximum depth of 65 meters. This paper describes a project-specific soil grouping system that is primarily based on soil characteristics for tunneling derived from tests including Atterberg limits, grain size, swelling, mineralogy, triaxial, pressure meter, and consolidation, which differentiates the project from past area tunnel projects using descriptive systems based primarily on area geology.

By Steve Kral

It seems that mining has been in the doldrums for awhile. Except for gold, metals prices remain depressed. And economic conditions in the United States and around the globe have put governments in a financial bind. This affects new building and infra-structure repairs, which, in turn, have a major impact the building materials industry. Add to that the severe environmental and regulatory restrictions placed on the mining industry in developing new mines and expanding existing ones. It’s enough to make a mining engineer/geologist/metallurgist go sell real estate. So why do those employed in the mining industry stay in the business and remain optimistic? Many of them will say that they have been through down cycles before and know that an upswing is in the offing. They also know that society will always need the commodities they produce. And they love the challenge. The challenge in mining’s case is producing commodities as cheaply as possible, in an environmentally sound manner and improving the quality of life in the communities where they work.

Jan 1, 2003

By Ravi Ray, Kostas Kaklis, Zach Agioutantis

"Modern underground mining is becoming more complex and geotechnically challenging. The engineer uses numerical, analytical, and data-driven methods (empirical and/or experimental) or their combination to overcome these challenges. Each method has its advantages and disadvantages. Nevertheless, given the amount of innovation and experience involved in developing each of these techniques, it will be prudent to use all their benefits rather than favoring one technique over the other. Pillars are the most important support element in an underground mine. A holistic geo-mechanical solution needs to be determined to design mine pillars using a proper sequence and exact mix of the three methods. A combination of these methods, in sync, can encompass the several advantages of the three methods while eliminating their disadvantages. This paper presents a conceptual three-tier solution to the pillar design problem, to improve its design pedigree, using a proper combination of numerical, analytical, and data-driven methods. At the focus of this proposed method lies the Ground Reaction Curve (GRC) concept.INTRODUCTIONAlthough the stability analysis of underground excavations is a challenging problem, its understanding has improved tremendously over recent years through the use of improved tools and techniques. The trial and error method was replaced with more scientific methods like the empirical and analytical methods that are still in use today. Empirical methods were developed based on large data sets obtained from experiments and observations (e.g., coal pillar strength equations). Analytical methods were developed based on mechanical understanding of stability (e.g., safety factor for vertical pillar loading, Convergence Confinement Method). Improvement in computing power and numerical techniques led to the development of several numerical methods (e.g., finite difference, finite element) suitable for geo-mechanical analysis.Each of these methods have certain advantages and limitations. Nevertheless, the user is often puzzled over the proper method selection and over the proper sequence of using them. This exercise becomes more challenging when different methods are combined, where, for example, one has to estimate the pillar strength based on empirical equations (e.g., Mark-Bieniawski coal pillar strength equation), determine the factor of safety based on an analytical approach (e.g., tributary area load divided by pillar strength), and analyze pillar-strata interactions using numerical analysis (see Esterhuizen, Mark, and Murphy, 2010b).Challenges increase when current pillar design methods are designed as passive structures to balance the fixed dead weight of the overburden. This classic suspension design approach does not recognize the self-stabilizing capacity of the overburden (Frith and Reed, 2018). A practical solution to address these issues is the use of numerical analysis. However, one should always keep in mind that the numerical modelling approach may have certain practical limitations."

Jan 1, 2019

By Will Foreman, Douglas D. McLearie, Edwin K. H. Tong, William H. Hansmire

Hong Kong’s Strategic Sewage Disposal Scheme (SSDS) Stage I involves the provision of a system of deep tunnels for transporting to a central treatment works wastewater collected from a number of catchments around Victoria Harbour. For the SSDS Stage I works, about 24 km of tunnels have been excavated in hard rock at depths ranging from about 80 to 150 m below Victoria Harbour and the surrounding heavily developed areas of Kowloon and Hong Kong. Five tunnel boring machines(TBMs) with diameters ranging from 3.2 m to 4.3 m were used to excavate the tunnels. Tunnel excavation has been completed and tunnel linings are in progress. Major tunnelling issues such as ground stabilisation and water control encountered in the project are summarised. An overview of one of the possible future tunnel systems that might be adopted in subsequent stages of SSDS is also presented.

Jan 1, 2001

By J. L. Brinkman

"One of the most common emissions from detonating explosives are nitrogen oxides (NOx), which are potentially deadly if inhaled. Lab studies estimate emission quantities, though great variation is shown based on site-specific conditions, and lab tests may not fully represent field results. Field VALUES (have not been measured due to the vast area affected. OSMRE recently promised to release a ruling regarding surface mine NOx production. Once the ruling is implemented, it may eventually be necessary to monitor site-specific NOx production from blasting. A small unmanned aerial vehicle system (sUAS) is able to carry a NOx gas monitor, rapidly travel to the blast location, and to follow resulting clouds of dust and emission gasses. This project will perform laboratory tests to expand on current estimations, determine an optimal method for collecting data, and evaluate the ability for this unique application of sUAS to assist in health risk assessment for mine employees and nearby communities. Additionally, large initial NOx concentrations do not necessarily correlate to unsafe conditions, and this project will be ground breaking in observance of surface blasting emission dispersion. The project is still in early phases at the time of submission for this paper (Nov 1, 2017). Therefore, this paper focuses primarily on summarizing background research related to the project and a description of the project plan. INTRODUCTION Nitrogen oxide gases (NOx) are common emission by products of surface mine blasting. These gases can potentially cause risk to human health and safety, both for mine workers and communities near the blast site. However, these emission quantities are largely unmeasured and no attempts have been made to relate these VALUES (to human health risk. The primary objectives of this project are to determine actual quantities of emission gases produced during surface blasting, to evaluate immediate and long-term risks to nearby people, communities, and ecosystems, to develop a system for mine employees to easily monitor emission and risk levels, and then provide guidelines for mitigating health risks based on a location’s emission results. BACKGROUND Current research regarding health risk produced by surface mine blasting NOx emissions is extremely lacking. Estimations have been made based on laboratory research, though these same test results show wide ranges of possible gas quantities produced based on site-specific conditions. Even if these estimations are accurate, no method has been created to relate gas quantity produced to human exposure concentrations. To further understand this field, background research was studied pertaining to blasting emission gas formation, laboratory and field measurements, harmful effects of blasting emission gases, and relevant government regulations. Background on Blasting Emission Gases"

Jan 1, 2018

By Carsten Rühlemann, Thomas Kuhn, Cornelia Kriete

"Any economic calculation with respect to potential submarine mining activities requires reliable analytical data on the contents of valuable metals in these ores, including trace metals such as rare earth elements as well as Ti, Mo, V, Zr and Li. Due to the very special matrix of ferromanganese nodules (30% manganese oxides, 10-20% iron oxides, silicates; see Kuhn et al., this volume), their geochemical analyses pose a real challenge. Available ferromanganese nodules reference materials, e.g., NOD-P1 and A1, JMn-1, GBW07249, SDO-4 to -7 and NM2388, generally have only a few certified values for trace elements. Published data for these reference materials, collected in the GeoReM database (http://georem.mpch-mainz.gwdg.de/) are either rare for high technology metals or widely scattered for certain elements, especially the PGEs. Since most of these materials were released in the 1990s, many analytical procedures have seen significant advancement.In order to facilitate analytical quality assurance during exploration and potential future mining activities, the German Federal Institute of Geosciences and Mineral Resources (BGR) has contracted the Central Geological Laboratory of Mongolia (CGL) to produce a certified reference material for nodule analytics. Certified reference materials provide the highest level of reliability in geo-analytical measurements currently available and the CGL has a long-term experience in producing geological reference materials. Recently, the CGL was accredited as a reference material producer according to ISO Guide 34 by the American organization ACLASS (Assured Calibration and Laboratory Accreditation Select Services). Furthermore, it has been accredited as a testing laboratory according to ISO 17025."

Sep 1, 2014

By D. Hopkins, D. Türler, R. D. Giauque, W. B. Davis, M. Karaca

In a highly collaborative research and development project with mining and university partners, sensors and data-analysis tools are being developed for rock-mass characterization and real-time measurement of mineral content. Determining mineralogy prior to mucking in an open-pit mine is important for routing the material to the appropriate processing stream. A possible alternative to lab assay of dust and cuttings obtained from drill holes is continuous on-line sampling and real-time x-ray fluorescence (XRF) spectroscopy. Results presented demonstrate that statistical analyses combined with XRF data can be employed to identify minerals and, possibly, different rock types. The objective is to create a detailed three-dimensional mineralogical map in real time that would improve downstream process efficiency.

Jan 1, 2002

By R. Marrill

Mining is a complex and intensive industry. Extracting raw material with different shapes, sizes, chemistry from the earth?s crust and transform them into a standardized and high quality final product is a big processing challenge - which involves energy and control on large scales. Not only is the physical work challenging, the mining industry today is facing unprecedented challenges: Decline of mineral grade and reserves, cost escalation for new developments and modernization, regulations, safety, lack of skilled people, and market uncertainty are the new constant. It is clear that process control and management of electrical power will be of increasing importance to the recovery rates the mine will achieve. The objective of this paper is to provide a quick vision about future trends and evolutions in technology related to these fields and their impact on Electrical Safety and Control of the mineral recovery. The paper will cover trends in safety, energy management and efficiency, communications of data, control room evolutions, plant integration, other control technologies, and we will examine how these technologies provide information and the benefits of aligned reporting systems to address current industry challenges. More than just the trends or breakthrough concepts, current technologies are available today that can be applied in the mineral recovery operations now to help overcome anticipated future challenges will be presented later in this document. Finally, a brief discussion to look at some real tools to help make real time changes to the process while maximizing recovery and optimizing cost.

Feb 27, 2013

By Miles T. Stephens, Felipe Calizaya, Jacob O. Kingston

Currently, the Bear Canyon Mine is facing the challenge of excessively high coal and rock temperatures in one of its headings. In Mine No.3, the air temperature at the 6th Right panel reached 36.4ºC and the coal 83.9 ºC. Due to these severe work conditions, the mining plan has been altered by changing the mine direction to avoid the high temperatures. To investigate the problem, drill holes were developed from the entries and the rock temperatures monitored using K-type thermocouples. The measurements confirmed the existence of localized “hot spots” in the mine. This paper presents a summary of ventilation surveys that were conducted in this mine. It includes the results of coal and rock temperature measurements from drill holes, interpretation of results using a heat flow simulator and the identification of hot spot areas. It also includes a summary of methods that were developed to reduce the hazard and control the problem.

Jan 1, 2005

By P. Dhar, H. R. Kota, M. Thornhill

Precipitated calcium carbonate is used as a filler and coating material in the manufacturing of paper because of its high brightness and light scattering characteristics. However, beneficiated calcite has similar potential, given the fact that the industrial specifications are already achieved. For paper industries, the requirement is that the desired product should be pure and have a brightness of 93 to 95 percent. A very-high-grade calcite deposit of around 92 percent is located in the north of Norway, which is used as the raw material for ground calcium carbonate (GCC) feed for the paper industries. There is a substantial amount of calcite resource, which has pyrite and pyrrhotite as major impurities. These sulfides, even when present in minor concentrations, impart color to the end product (paper). Removing these minerals is estimated to increase utilization of the deposit by 10  percent, which represents several million tonnes of calcite marble. Due to the requirement for environmentally friendly reagents and chemicals by the mineral industry, fatty di-amines are being tested for pyrite and pyrrhotite flotation. The interaction mechanism of diamine with the main components of the ore were studied and optimum conditions for removal of sulfide impurities are outlined.