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By Walter Kahn

Increasing consideration is being given to simplifying traditional methods of tracing pipelines and maintaining required temperatures of stored fluids. Because of their reduction in capital costs, virtual elimination of maintenance. ease of control and "cleanliness"; interest in electrical techniques has accelerated. 1,2 Resistance cable and other heaters have been given some attention. but less well known in the recent introduction of thermal conductive coatings. This paper is addressed to the use of thermal conductive coatings for heating fluid-transport piping and storage tanks. Emphasis will be given to the simplicity, efficiency, and versatility of design and application which their unique properties further contribute to the general economics of electrical heating.

Jan 1, 1965

By D. J. Pyra, J. Kudelko, Korzekwam W.

Polkowice region (Lower Silesia, Poland) is an area, where the copper mining activity started about 40 years ago and new technologies were applied. There are 3 underground mines, 3 processing plants, tailings pond (the biggest one in Europe), pipelines for flotation waste transport, railways. Although new technologies were applied during the copper ore exploitation, the environment in this area were polluted mostly by dust containing copper, lead, zinc and arsenic. Estimated values of heavy metals in polluted soils were compared to the natural contents of this metals. The geochemical background for Polkowice area was defined. The pollution zones occur around mining facilities. Copper ore exploitation and processing is planned for the next 20-40 years depending on market situation. After mines and other facilities closing the most important problem will be sustainable development of this area. To evaluate the scope of revitalization activities the analysis of recent soil environment condition will be necessary as well as forecasts for pollution migration. Geostatistic methods used also in mining will be very helpful for this task.

Jan 1, 2005

By P. Ulrich, V. Svalbonas

The early to mid 1980s was a period of mining consolidation, and many senior design engineers retired from the mill industry. Similar conditions have existed in the last few years. This creates a loss of a tremendous amount of experience. This paper is a look back by two senior mill designers who survived the dips in both time periods. From a continuous design practice of over 25 years, mill designs and fabrication practices are surveyed with a view of identifying what works, and is necessary, and what doesn’t, or is not necessary, in the creation of a safe, economic, long-lived grinding mill.

Jan 1, 2001

By S. Rukhaiyar, M. Ramulu, G. Pradeep, P. K. Singh, P. B. Choudhury

The drill and blast method is the most prominent rock excavation method used in mining and civil engineering projects. The ground vibration is the most undesirable effect of the blasting and needs to be controlled. The blasts are designed so that ground vibration at nearby structures must remain under the prescribed limit. Various empirical blast vibration attenuation models have been presented to estimate the ground vibration for designing purposes. These models assume ground vibration as a function of distance and maximum charge per delay. United States Bureau of Mines (USBM) model is most commonly used for the blast design. However, the uncertainty associated with these models is seldom characterized, thus diminishing its reliability. The probabilistic Bayesian approach associated with the Monte Carlo method can easily quantify uncertainties associated with the model and its parameters. Thirty-three blast vibration observation data from a granite quarry in Kerala, India, is used to estimate the probability distribution of model parameters. Markov Chain Monte Carlo (MCMC) approach is used for sampling 12,000 samples for obtaining the posterior distribution of parameters. The uncertainty associated with model parameters is quantified from the posterior distribution, and this is further used to estimate the credible and prediction limits of the model. The point estimate of the most optimum value of the parameter is estimated using maximum-aposteriori or MAP estimate. The model parameters are also obtained using the commonly used least-square error method, which is a maximum likelihood estimation or MLE approach. It has been observed that the accuracy of the model obtained using both MAP and MLE approach is almost equal. However, the MAP estimate as per Bayesian probabilistic analysis has the added advantage that it can estimate the uncertainty of parameters as well as the model, which is not possible using the MLE approach.

Sep 27, 2021

By Devin Burns, Saima Ghazal, Michael Owusu-Tweneboah, Kwame Awuah-Offei

Trust in AI systems and the nature and amount of information about the system can influence decision-making. It is, therefore, crucial to understand how AI-powered monitoring systems (e.g., gas monitoring systems) influence miners’ trust and decision-making in emergency evacuation. This work focused on measuring the differences between how participants respond to a simulated underground mine emergency evacuation situation when warnings are represented as coming from a human or AI-based monitoring system. We also manipulated the amount of information participants received about the system, yielding a 2×2 between-participants survey design. The participants received an alert message about rising gas levels in a mine and provided a response on how they would react and reported their perceived safety. We also asked questions to assess their trust in, preference for AI over human-based gas monitoring systems, and whether they are willing to delegate the duties of underground gas monitoring to AI systems. The experiment results show the amount of information had a significant influence on miners’ trust and decision-making. The safety perception of participants based on age, number of children and ethnicity was significantly different from one category to another. This work provides valuable insights as the mining industry deploys AI systems to aid mine safety.

Feb 1, 2025

By K. C. Kocsis

"Diesel-powered equipment has allowed the mining industry to raise production rates and significantly improve productivity, as it is rugged, mobile and reliable, but its widespread use in underground mines has generated concerns regarding the exposure of mine workers to harmful diesel engine exhaust gases and particulate components such as diesel particulate matter (DPM), which has recently been classified as a human carcinogen by the International Agency for Research on Cancer. The agency expressed further concerns that workers’ exposure to high DPM concentrations can increase the risk of cardiovascular, cardiopulmonary and respiratory illnesses. Three emerging technologies could have the ability to replace dieselpowered equipment and remove DPM from underground mines: fuel-cell-powered mining equipment, battery-powered mining equipment and advanced material handling systems. This paper reviews them and assesses whether they have reached the point where the pollutants emitted by diesel-powered equipment can be removed from underground mines through the introduction of zero-emission mining equipment and power systems. Information is also provided from the results of a feasibility study, including a detailed cost benefit analysis, carried out at six Canadian and nine U.S. underground mines, which looked at the possibility of replacing diesel-powered production equipment with fuel-cell-powered equipment. The remarkable pace at which battery technology is progressing is also reviewed, and the feasibility of replacing diesel-powered mining equipment with battery-powered equipment is assessed. IntroductionHazardous pollutants in underground mines. Why is it important to remove diesel particulate matter (DPM) from underground mines? Over the past 40 years, diesel-powered equipment has allowed the mining industry to achieve rising production rates and major improvements in productivity, as the diesel engine is an economical source of power and diesel-powered equipment is usually rugged, mobile and reliable. On the negative side, the toxicity of some diesel exhaust gases is well known (Grenier et al., 2001), and the widespread use of diesel-powered equipment in underground mines has generated increasing concerns about the occupational exposure of mine workers to harmful diesel engine exhaust gases and particulate components such as DPM. Diesel equipment also entails other hazards like heat and humidity. Exposure to excessive heat can cause heat illnesses, such as heat rash, heat exhaustion and heat stroke (Donoghue, 2004; Roghanchi et al., 2016), and a hot and humid underground environment negatively affects the efficiency of the workforce, which may result in a decline in production output (Roghanchi et al., 2017)."

Jan 10, 2017

The National Mining Hall of Fame and Museum (NMHF&M) will celebrate its 25th anniversary on Sept. 22, 2012 when the 2012 class is inducted during a special ceremony in Las Vegas, NV in conjunction with MINExpo 2012. The NMHF&M will induct four men representing the equipment manufacturing, minerals exploration, copper and coal sectors of the mining industry. The diverse cross-section of mining industry giants joining the hall of fame include Glen A. Barton, J. David Lowell, Samuel Newhouse and John Cleveland Osgood. They will join 214 other mining industry pioneers when they are formally inducted into the National Mining Hall of Fame at the 25th Silver Anniversary Induction Banquet & Ceremony. These men were selected for being visionaries, leaders and ambassadors within their own sectors and across the industry at large.

Jan 1, 2013

By Josh Swank

Albert Einstein once said, ?the important thing is not to stop questioning.? In the mining industry, a lack of inquisitiveness may lead to a blissful ignorance but it certainly will not increase efficiencies. While one may claim necessity is the mother of invention, questioning and analyzing how methods and systems can be improved is the catalyst to discovering necessities. Understandably, when working in the middle of Canada?s oil sands, where trucks operate around the clock every day of the year, it is nearly impossible to pull the nose from the grindstone long enough to provide thorough analysis. But, fortunately, some manufacturers/inventors have assisted by examining the process and the ensuing headaches within this application.

Jan 1, 2013

By Collon C. Kennedy, Frances C. Hartogh, C. Joel Casburn

INTRODUCTION During the nineteenth century, the federal mining law was enacted with the objective of promoting the development of the western United States by providing unrestricted access to vast areas of federal land for mineral exploration. Prior to the advent of comprehensive federal, state and local land use plans, there was little, if any, regulation or restriction of mineral exploration activities. Today, the laissez-faire policies of the past that encouraged mineral exploration have gradually given way to the public's legitimate concerns regarding environmental protection, multiple use and planned land development. As a result, the contemporary prospector confronts a maze of statutes, ordinances and regulations with which he must comply to obtain the requisite approvals and permits before commencing mineral exploration on federal, state or private lands. This presentation will provide a broad overview of the exploration permitting process. The first section of this paper recommends certain general management practices to follow when attempting to obtain exploration permits. The second section presents two hypothetical cases, one involving a drilling program on private property in California and the other involving a drilling program and the removal of a bulk sample for metallurgical tests from federal land in Nevada. The cases are used to discuss jurisdictional issues and application of certain federal, state and county laws and regulations that pertain to mineral exploration. The final section contains a brief analysis of three important recent United States Supreme Court decisions. These decisions address the scope of the federal pre-emption doctrine as it applies to activities conducted on unpatented mining claims and the constitutional limits of permissible state and local land use and zoning regulations. PERMITTING PRACTICES The environmental impacts associated with mineral exploration generally result from the construction of drill sites, roads or trenches. Consequently, after the regulatory authority has considered the issues of permissible land use, the primary emphasis of the permitting process is to address problems related to pre-construction site identification and clearance, and post-construction site reclamation. The approaches taken to address these and other related issues vary with the scope of proposed work, the site, the appli-

Jan 1, 1987

By Sheridan A. Glen

As the Federal government along with individual states continue to grapple with the job of refining a comprehensive energy policy, coal continually stands out as an energy source which heralds a combination of old and new capabilities like an energy planners prophecy, but which is plagued with serious environmental constraints. To determine what level of coal utilization is ultimately possible for states East of the Mississippi, whose high sulfur content coal presents the most paramount of challenges, one must consider product availability, via existing transportation modes, the developing industrial markets and the ability of coal to meet the challenge of becoming an environmentally acceptable fuel. Gasification is emerging as a form of utilization, which during the next twenty years stands a good chance of being able to meet the challenge of making coal an environmentally clean, easily transport-able and usable fuel. It can be argued that, of all the potential ways of utilizing high sulfur coal, coal gasification is perhaps the most expensive, the most financially risky and carries environmental liabilities of its own. Synthetic gas and oil markets will undeniably be a function of price and demand, which, for the purposes of this paper, I'm assuming will begin to merge in the late 1980's and into the 1990's. This is also presuming that public utility commissions will allow favorable price structure ruling so that gasified coal products can be rolled into their respective rate base, much the same as synthetic natural gas from petroleum by-products are currently being priced. The comparative economic markets of coal to gas pro-duct have plenty of time to mature. There is an approximate twelve-year lead time needed to bring coal gasification plants on line which will be able to compete in the market place for natural gas and oil customers.

Jan 1, 1977

By T. R. Ellis

Considerable movement is afoot internationally to rationalize standards and regulations relating to valuations and the qualifications for valuation professionals. In July 2000 the International Valuation Standards Committee released expanded standards, and additional important improvements are planned by 2003. Possible updates to the International Accounting Standards (IAS) and potential adoption of IAS by the U.S. could significantly impact minerals appraisers. Standards designed specifically for mineral asset valuation are under development in Canada and the U.S., with Australia’s internationally respected VALMIN Code providing the benchmark. In the U.S., the all-encompassing Uniform Standards of Professional Appraisal Practice (USPAP) is annually modified and continues to gain deeper acceptance, while the SEC holds fast to its antiquated rule prohibiting reporting of a quantitative estimate and value for non-reserve mineralization. Some important international trade agreements are driving actions to free the trade in professional services. In July 2000, an international workshop was held to initiate discussion on minimum qualifications for appraisers to work internationally. Pressure for uniform minimum qualifications and rules for professionals internationally will continue to build. The U.S. is historically among the slowest countries to implement such initiatives, with its state level licensure barriers having the potential to cause some of its professionals to be stranded in an international backwater. Structural change is needed in Australia’s VALMIN Code to remove conflict with the latest International Valuation Standards. The mineral valuation standards developers of Australia, Canada and the U.S. should work jointly on updating VALMIN for global use.

Jan 1, 2001

By Michael Murphy, Gamal Rashed, Brent Slaker

Pillar stability continues to be a significant concern in multiple-level mining conditions, particularly for deep mines when pillars are not stacked or the thickness of interburden between mining levels is thin. The National Institute for Occupational Safety and Health (NIOSH) is currently conducting research to investigate the stability of pillars in multiple-level limestone mines. In this study, FLAC3D models were created to investigate the effect of interburden thickness, the degree of pillar offset between mining levels, and in situ stress conditions on pillar stability at various depths of cover. The FLAC3D models were validated through in situ monitoring that was conducted at a multiple-level stone mine. The critical interburden thickness required to minimize the interaction between the mining levels on top-level pillar stability was explored, where the top level mine was developed first followed by the bottom level mine. The model results showed that there is an interaction between numerous factors that control the stability of pillars in multiple- level conditions. A combination of these factors may lead to various degrees of pillar instabilities. The highest degree of local pillar instability occurred when pillar overlap ranges between 10 and 70%. On the contrary, the highest degree of stability occurs when the pillars are stacked, the underlying assumption is that the interburden between mining levels is elastic (never fails). Generally, for depths of cover investigated in this study, the stability of top-level pillars shallower than 100 m (328 ft) or with interburden thicknesses greater than 1.33 times the roof span—16 m (52.4 ft) in this study—does not appear significantly impacted by pillar offset. The results of this study improve understanding of multiple-level interactions and advances the ultimate goal of reducing the risk of pillar instability in underground stone mines.

Jul 27, 2022

By W. Missildine, J. K. Hrica, I. Benbourenane, T. J. Orr, J. L. Bellanca

Each year, haul truck accidents account for a large portion of mining injuries and fatalities. To better understand why these accidents continue to occur, researchers from the National Institute for Occupational Safety and Health (NIOSH) utilized a cognitive task analysis methodology to identify the user requirements of surface haul truck operators and assess differences in perceptions between operators, managers, health and safety professionals, trainers, and maintenance personnel. Additionally, researchers used the critical decision method to focus on better understanding the cognitive demands, decision-making, and problem solving during nonroutine incidents. The preliminary results of this study identify and explore themes within the broad categories of hazards, skills & expertise, and training and provide detailed accounts of nonroutine incidents such as near-misses, loss of control, and collisions. These accounts reveal insights into operator decision making and event progressions that can then be used to build more realistic training scenarios and address hidden hazards and root causes of these incidents. These results, along with potential solutions offered by study participants, can inform future research and help identify creative interventions that can be used by mine operators to address haul truck safety issues

Mar 2, 2022

By C. L. Kosmoski

In recent years, coal mining safety has attained national attention due to several highly publicized disasters. Despite these threats to worker safety and health, the U.S. relies on the mining of coal to meet its need for electrical power, with 42% of electricity in the U.S. generated through the burning of coal (U.S. Energy Information Administration, 2012b; United Mine Workers of America, n.d.). Furthermore, the production of coal continues to increase and reach record levels every year (National Mining Association, 2012; U.S. Energy Information Administration, 2012a). For this reason, the coal mining industry must continue to find ways to protect its workers while maintaining productivity. One potential approach to protecting workers while maintaining productivity is through improving the safety culture at coal mines. In order to achieve this culture, operators, employees, the inspectorate, etc. must share a fundamental commitment to safety as a value. This type of culture is known in other industries as a ?safety culture,? and can be defined as the characteristics of the work environment (such as the norms, rules, and common understandings) that influence facility personnel?s perceptions of the importance that the organization places on safety. Fundamental to improving safety culture within an organization is understanding the existing safety culture; improvements cannot be made without first elucidating areas that require improvement. This manuscript details the process undertaken by researchers at the National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) to assess the safety culture at five underground coal mines across the United States. The purpose of this manuscript is to present the aggregated results from those five safety culture assessments conducted at underground coal mines. Additionally, some general recommendations for areas where coal mines might focus their attention as part of their attempts to improve safety culture are offered.

Feb 23, 2014

By Ebrahim Farrokh

Ghomroud water conveyance tunnel project is under construction using shield Tunnel Boring Machines (TBM) for a total length in excess of 50 km. Phase 1 of the project included 36 km of tunnel divided into four lots (1, 2, 3, and 4) of nine km each. Lots 3 and 4 of this tunnel for a total length of 18 km were combined into one award and have been constructed using a double shield (DS) TBM or one path system. Extreme ground convergence in some sections of the tunnel has stalled TBM performance in early reaches, due to face collapse and shield jammings. This paper presents the latest update on the tunnel progress and impact of ground convergence on machine performance based on the information obtained from field observations. Also, the method and results of tunnel convergence measurements were studied in conjunction with geological parameters and an attempt was made to correlate TBM operational parameters and ground convergence. The result of the analysis indicates a good correlation between machine?s operational parameter and tunnel convergence and can be used as an indicator of the potential for high rates of convergence. An early warning on ground convergence is essential for taking precautionary measures to avoid TBM jamming and related long delays and costs.

By Phil Shelton

What exactly does clean coal mean? Mining coal creates dust and releases methane gas. And burning coal liberates CO2 and emits particulates, including SO2 and NOx. Coal creates wastes that are often stored in unsightly and potentially dangerous slag heaps and lagoons. When clean coal technology is discussed, it sometimes seems that creating modern or ?ultra super critical? coal-fired power stations is presented as the main or even the only answer. However, there may be a more holistic approach. Using the energy potential of coal is always going to have environmental impacts. Some of these will be negative. But the need to secure future energy resources demands that society tackle these negative issues and find ways to minimize and offset them.

Jan 1, 2010

By Casters B. Foster

The U.S. Department of Energy has undertaken, in a cost sharing partnership with industry and utilities, an extensive coal-oil mixture (COM) combustion program in a number of promising applications. One of these is the injection of COM through tuyeres into a blast furnace in lieu of oil. From work done previously, it has been established that COM can be burned in existing oil, fired facilities. The issues being addressed by the current DOE program are: 1) determination of best available technology to achieve environmentally acceptable operation, and 2) determination of applications for which COM can be utilized economically.

Jan 1, 1978

By David R. Maneval

At the turn of the century the keys to industrial success were coal and iron. At that time, Pennsylvania was the ranking mineral producer among the States and close to 90% of the Nations energy output was generated by coal. The growth of this Common-wealth into the greatest industrial State in the nation has been due to the huge resources of easily accessable coal found by the early settlers. It was the development of these deposits that provided the United States with a new source of fuel energy. For nearly a century, the Commonwealth was the chief powerhouse of our nation and the chief source of its industrial blood and bone. In 1928 it was truly said that coal was king in Pennsylvania. Pennsylvania that year mined a billion dollars worth of coal. A single train carrying this output would reach more than twice around the world at the latitude of Pennsylvania. Coal formed nearly 67% of the freight of Pennsylvania and was responsible for its four billion dollar iron and steel industry. Coal was the real reason why Pennsylvania although 32nd in size was second and not tenth or fifteenth in wealth, population and industry. Pennsylvania was slow to take-up her heritage as the greatest coal producing State in the union. But the knowledge that coal was present was not slow in accumulating. In fact the Indians were aware of its existence long before the white man arrived. They knew that many of the hills were underlain with black stones that would burn. It is reasonably certain that Arnold Viele, the first white man to cross the mountain in this State saw coal in them in 1692. But awareness was not enough. The population in these days was confined to southeastern corner of the State and the population at this time had little need or interest in the resources further inland. Pennsylvania anthracite was discovered in 1762 but was first regarded only as a curiosity. Commercial productions started in 1820. This stimulated the development of many native industries and extensive canal system and afterwards an elaborate net-work of railroads were constructed at great costs to bring the products of the hard

Jan 1, 1971

By Robert Burgess, Dale Gill, Jaco Steyn, Bill Kyslinger

"With mining, especially coal extraction, comes the necessity of supporting the roof. Since the 1950s, the primary method for roof support has been the use of roof bolts. Roof bolting is considered one of the most hazardous jobs in underground coal mining. In 2004, there were 3,405 injuries reported to the U.S. Mine Safety and Health Administration (MSHA). Of those injuries, 17 percent were associated with bolting machines (593 injuries). The majority of the injuries resulted from rock falling from supported roof. However, injuries involving a part of the body being struck by, or caught between, during bolting and drilling occurred with relatively high frequency (Burgess and Steiner, 2007).Roof drilling and bolt installation is labor-intensive and repetitive. These labor-intensive and repetitive requirements can lead to cumulative trauma. Operators are expected to perform a considerable amount of lifting, carrying, bending, reaching and stretching. Back and shoulders become sore from bending and twisting to install bolts or lift and position drill steels, wrenches and bolts. Confined operator spaces also contribute to difficult and awkward working positions for the operators (Cornelius and Turin, 1998).In South Africa, the majority of the roof bolting machines used are “man-in-position” style machines (Fig. 1). This puts the operator in close proximity to where the drilling and bolting process is performed. When proper operation procedures are followed, it has been proven to be a very effective, productive and safe system. The MSHA-certified automatic temporary roof support (ATRS), canopies and dust collection system of Fletcher bolters all provide the operator with unparalleled protection. However, there are some occupational hazards inherent to the zone located next to the drilling and bolting zone. This has led some customers to request relocating the operator away from this zone. The idea being that the operators will no longer be located in the face area, greatly reducing their exposure to dust, noise, machine and geological hazards."

Mar 1, 2017

By H. G. Schoenike

A subsequent spin off of the energy shortage is the new life for barite. Over 90% of the barite produced in the world is used as a weighting material in oil well drilling muds. Business is booming; the price of barite has risen; scarcity is imminent, and exploration is going full steam ahead. New barite-producing companies are being formed and many of the barite consumers are considering becoming producers. Prospectors have found a new "love," smaller deposits are being explored, and old deposits, previously rejected, are getting a reappraisal. Even barite tailing piles are being resampled.

Jan 1, 1980