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Why Innovate in Mining? ?Obvious, right? ?Increase productivity and profitability ?Improve safety and ergonomics ?Improve our environmental record and eliminate liabilities ?Implement process control methodology ?Introduce information systems technology to gain control ?Low hanging fruit ?Reference ?Heather Ednie, Innovation CIM Magazine Feb. 2006 ?Peck & Skinner, Getting better bang for your buck with technology

May 1, 2006

By Dan Brown

A method is outlined for computing the contribution of a micropile group to global stability of a sliding mass. The forces in the micropile are computed in a way which accounts for the effect of soil mass movement on the mobilization of axial and shear forces and which maintains compatibility between shear and axial force as a function of displacement. The method provides a rigorous model to incorporate the pile forces into the stability calculations, including the effect of pile forces on the resultant shear and normal forces at the sliding surface. This paper demonstrates the proposed solution using a simple example slope.

Jan 1, 2007

By Elaine T. Cullen

Miners, like many skilled blue-collar workers, are not traditional learners. They have not generally been successful in classroom-type settings, preferring to learn on the job in a hands-on environment. U.S. miners are required to have annual safety training, but they rarely view this positively. In fact, it has been called “safety jail” by many of them, who regard it as a time to get a little extra sleep. The challenge then, was to find a way to develop effective safety training for these people, particularly in view of the fact that their work is among the most dangerous of all occupations. Miners are born story tellers. They share “near-miss” stories, stories about master miners they have known, and stories about how things used to be. These stories not only pass along information about what will happen if a miner fails to respect the mining environ-ment, they also instruct listeners in the culture of mining and the values it embraces. Stories, it seems, are a way to get safety messages to miners, especially inexperienced ones, and using older, wiser miners in these stories is an obvious choice. This paper will discuss how the training videos created to get safety messages to miners were developed, how “master miners” and story lines were chosen, and how the resulting videos have been received in the mining industry.

By R. Bokotko, J. D. Miller, J. Hupka

Laboratory results from an initial study on the removal of SO2 from gas mixtures are reported using air-sparged hydrocyclone (ASH) technology. Tap water and alkaline solutions were used for absorption and the influence of gas flow rate, water flow rate and length of the ASH unit were investigated. Complete removal of SO2 was possible with very favorable kinetics. The efficiency of sulfur dioxide absorption from air using the ASH is compared with the efficiency of conventional technology.

Jan 1, 2002

By Laura E. Beverage

The Changes 2008 Brought -MSHA recently posted a PowerPoint to its website which shows statistical performance information for fiscal years 2000 to 2008. -Interesting statistics: Fatality rate in Coal dropped by nearly 30% (.0348 to .0246 per 10,000 workers)

Jan 1, 2009

By Kristine M. Krajnak

Occupational exposure to hand-arm vibration through the use of powered hand tools can result in reductions in tactile sensitivity, grip strength and manual dexterity. In fact, even acute exposures to vibration cause shifts in vibrotactile thresholds in exposed fingers (2,4,5). Although reductions in tactile sensitivity after acute vibration exposures are transient, cellular changes associated with this shift in sensitivity could lead to the more permanent reductions in tactile sensitivity that are a common symptom of hand-arm vibration syndrome (HAVS). Methods Animals. Male Sprague Dawley rats (6 weeks of age) were used for all experiments. Animals were housed in AAALAC accredited facilities, and all procedures were approved by the NIOSH Animal Care and Use Committee and were in compliance with the CDC guideline for care and use of laboratory animals. Vibration exposures were performed by restraining rats in a Broome-style restrainer, and securing their tails to the vibration platform using 6 mm wide straps that were placed over the tail every 3 cm. Restraint control animals were treated in an identical manner except that the tail platform was set on isolation blocks instead of a shaker. Tail temperature and current perception thresholds (CPTs). Rats were exposed to 4 h of tail vibration (125 Hz, 49 m/s2), or restraint. Tail temperature was collected prior to and immediately following the exposure using an infra-red camera. Sensory neuron function was assessed by measuring CPTs with a Neurometer (Neurotron, Baltimore, MD). Transcutaneous nerve stimulation was applied to the C10 region of the tail. Three frequencies were used to test specific fiber types (5 Hz – C, 250 Hz - Ad, and 2000 Hz – Aß). The intensity of the stimulus was automatically increased in small increments until the rat flicked its tail. Tests at each frequency were repeated until the animals displayed 2 responses that were within 2 CPT (or 0.02 mA) of each other (2-4 tests/animal). CPT tests were performed prior to the exposure, immediately following the exposure, and 24 h after the exposure. Data Analyses. Temperatures were analyzed using a one-way ANOVA with animal as a random variable. ANCOVAS were used to analyze the CPTs at each frequency. Temperature at the time of the CPT test was used as a covariate, and animal was used as a random variable Results Tail temperatures declined between pre and post exposure (F(1,25) = 62.85, p < 0.001; mean ± sem pre 25.96°C ± 0.42, post 20.71°C ± 0.77), but were back to baseline levels by 24 h after the exposure in both groups of rats. The ANCOVAs demonstrated that exposure to a single bout of vibration did not alter sensitivity of C (5Hz) or Ad (250 Hz) fibers to stimulation.

Jan 6, 2006

The stability of surfactant-free foam films was studied using the thin film pressure balance (TFPB) technique. In pure water, it was not possible to produce foam films due to weak film elasticity and strong hydrophobic force. In the presence of NaCl, however, the hydrophobic force was sufficiently dampened to allow metastable films to form. At 10-5 M NaCl, the equilibrium film thickness reached a maximum of approximately 130 nm at pH 6.0-7.3. The thinner films obtained on either side of this pH range was due to the increased ionic strengths associated with the HCl and NaOH additions for pH control.

Jan 1, 2009

By Tianfei Liao

Extensive site investigations revealed that abandoned shallow mine workings exist under a site planned for construction of a major new facility. Since the mine voids were susceptible to collapse, they were stabilized by grouting. After completion of the mine remediation, three types of deep foundations (micro-piles, auger-cast piles, and drilled piers) were considered for this site. Micro-piles spread the load via the bond between the pile and the bedrock. Without significant length socketed in rock, the axial load of auger-cast piles and drilled piers has to be concentrated on end bearing. Although spreading the load is preferable in this environment, economic consideration dictated the choice of drilled piers for construction.

Jan 1, 2009

By D. M. Walters

To achieve safe and healthy working conditions in shaft sinking operations, ventilation, and where necessary cooling, must be provided. These requirements are considered for sinking vertical, sub-vertical and decline shafts. Regulatory requirements, determining air volumes and amount of cooling required, the various ventilation methods used such as force, exhaust, twin columns, air reversal using four gate systems and the equipment required to achieve this, are discussed. Consideration is also given to the sinking of single and twin declines using diesel equipment, calculating the air volumes required to dilute pollutants and the various methods for achieving this. Also discussed is the importance of having early ventilation design input to the overall design of the mine. In many cases ventilation can be the prime determinant for the size and configuration of the shafts or declines that have to be sunk.

Jan 1, 2009

Electrostatically charged water droplets efficiently suppress breathable dust produced during open air rock crushing operations, according to recently completed independent tests conducted for the Environmental Protection Agency. Since a primary rock crusher produces very heavy clouds of dust, this application was selected as an appropriate test site to measure the efficiencies of new "charged fogging" equipment in mining and mineral processing operations. EPA&apos;s Industrial Environmental Research Laboratory, Research Triangle Park, NC, contracted TRC-Environmental Consultants Inc. of Wethersfield, CT, to conduct a full-scale demonstration of a recently developed electrostatic fogger, designed to project a charged fog spray at distances up to 15.2 m. Test results indicated overall fogger efficiencies of approximately 70%. The Fogger IV* employed in these tests is reportedly the largest charged logger ever made, with an extremely long operating range. The original fogger was designed for indoor dust control; this fourth generation version is designed for fugitive dusts, indoor and outdoor, and has an operating range up to 15.2 in.

Jan 6, 1981

By Neil J. Mansfield, Setsuo Maeda

The purpose of using experimental subjective and/or perception methods is: (a) to understand human subjective impressions of the physical characteristics of vibration; (b) to determine the relationship between the subjective perception of some aspect of the vibration and an evaluation index of the physical vibration characteristics; and (c) the establishment of target values for design of vibration environments in terms of human sensation of vibration characteristics. In order to understand the relationship between a physical measure of the mechanical vibration and the subjectively perceived aspect of the vibration environment, experimental methods shown in Table 1 have been used1. [ ] The constant measurement methods of Table 1 are mainly used for measurement of the threshold of human sense. The subjective scaling methods are mainly used for obtaining subjective (or proportional) scaling between the perceived quantity and physical quantity. In this review, the fundamental approach of experimental methods for obtaining the target values used in the design of vibration environments, and the different findings between the subjectively perceived methods for evaluating human response to vibration characteristics and the physical quantity of the vibration environment are summarized. Fundamentals of Subjective Scaling The relationship between the experimental psychological methods for providing target values in the design of the vibration environments and the physical quantities is illustrated in Fig. 1. Vehicle mechanical vibration can be characterized using many metrics, and these can be considered the ‘input’ to the human. In order to predict subjective responses to the vibration, it is necessary to link the characteristics of the source of vibration and human reactions, the ‘output’.

Jan 6, 2006

By Jiwen Zhang

Abstract Due to the blocking nature at the crusher station, straightforward application of queuing theory cannot give realistic results on the performance of a shovel-truck-crusher system. A new queuing network-based model has been developed in which, the crusher station is formulated into an open queuing network and the whole shovel-truck-crusher system into a closed queuing network with the crusher station as a special server. To fully account for the influence of blocking, Monte Carlo simulation is first used to obtain the performance parameters of the open queuing network for the crusher station. The closed queuing network for the entire system is solved by applying the Extended Summation Method (ESUM), in which the crusher server is described by the simulation results. The model has been applied to the Yuanbaoshan open-pit coal mine to analyze its shovel-truck-crusher system and to improve its efficiency. Results indicate that the blocking at the crusher is an important factor affecting the crusher output and in turn the efficiency of the whole system, and prove that the model can realistically describe the behavior of such systems.

Oct 1, 2009

By K. Heindlhofer

Estimates of the "plasticity" of a metal are commonly deduced from three types of test—tensile, torsion and impact. The several results have been more or less at variance, though this disparity has attracted little notice, largely perhaps because they have been expressed in different terms. The discrepancy between the results of the three tests becomes obvious when each is made at a series of low temperatures, for the temperature range within which the "plasticity" of iron largely disappears proves to be very different in the three types of test. The rather abrupt disappearance of "plasticity" of iron within a narrow temperature range cannot be due to any physicochemical change (such as a precipitation) taking place in the material at that time, because the original plasticity is immediately regained when the temperature of the material is brought above the sensitive range. Accordingly this difference in behavior shows that the "plasticity" of a metal depends upon the mode of action of the stresses which produce the deformation, and therefore upon the method of test. Analysis of the stresses leads to the conclusion that the observed plasticity of a metal is determined by the relation between its resistance to rupture by separation and its resistance to shear (slip), on the one hand, and between the effective normal and shearing stresses on the other; and that the relation between the two resistances does not in general remain constant with change of temperature, and may somehow be altered to some extent by the previous treatment of the specimen. This suggests the view that the results of none of the usual mechanical tests are directly comparable even for a single metal tested at a series of temperatures, or for a series of metals at one temperature, because the proportion of the total resistance of the metal to the test contributed by the

Jan 1, 1935

By William R. Yernberg

The Society of Economic Geologists (SEG) held its biennial conference May 14 through 16, 2006, in Keystone, CO. SEG is an international organization with about 3,500 individual members with interests in economic geology. The 2006 SEG conference theme was “Wealth creation in the minerals industry — integrating science, business and education.” The conference exceeded expectations with 705 participants, including 102 students, from 44 countries. The conference featured 30 oral presentations, 24 professional posters and more than 70 student posters. The conference also included a trade show with 50 vendors, numerous field trips, workshops and social activities.

Jan 1, 2006

By Fred N. Kissell

In This Chapter [Ventilation and methane sampling guidelines for conventional shafts Dealing with restricted spaces where methane can accumulate Ventilation and methane sampling at raise bore drills and Filling shafts at closed coal mines] It is not unusual to encounter methane gas during shaft excavation or shaft-filling operations. Shafts into coalbeds usually produce the most methane, so the information in this chapter applies primarily to shafts at coal mines. Nevertheless, much of the information is relevant for noncoal mines that have methane in the mine or in the overlying strata. METHANE IN SHAFTS EXCAVATED BY CONVENTIONAL MEANS (DRILL, BLAST, MUCK) [ ] Ventilation. Shafts excavated by conventional means are ventilated with a fan on the surface connected to ductwork that extends down into the shaft (Figure 9–1). Shafts into coalbeds should have ventilation systems designed to handle the higher gas flows to be expected as the shaft excavation passes through any over-lying gas-containing strata and nears the coal-bed to be mined. Following are some simple ventilation guidelines for the minimum amount of air required and the selection of the ventilation duct: • Provide enough air to meet the mini-mum OSHA tunnel requirement of 30 ft/min air velocity in the open shaft, as specified in 29 CFR2 1926.800(k)(3). For example, a 20-ft-diam shaft having

Jan 6, 2006

Nominating Committee.-On the recommendation of the President, the Board of Directors, at their meeting on Apr. 25,1913, appointed the following Nominating, Committee to nominate officers and directors for next year: John Hays Hammond (Ex-President), Chairman. Robert H. Richards Chairman of Boston Local Section. Richard S. McCaffery, . . . . Chairman of Spokane Local Section. Chester F. Lee Chairman of Puget Sound Local Section. Frederick G. Cottrell, . . . . San Francisco, Cal. Charles W. Goodale Butte, Mont. James W. Maleolmson, . . . . Kansas City, Mo.

Jan 5, 1913

By R. M. Owens, J. F. Lupo

The Shirley Basin Uranium mine, located in southeastern Wyoming, USA, was an open pit mining operation consisting of a series of several open pit mines excavated into poorly consolidated sandstones, siltstones, and claystones. Since the initial open pits were developed in 1969, slope failures have plagued the mine and mining operations. These slope failures have persisted into the current mine reclamation period. When the mine was first developed, the open pit slopes were designed to range between 45 to 55 degrees. Numerous slope failures during mine development required the pit slopes to be redesigned with slopes as shallow as 26 degrees. At present, movements are occurring within the open pits on reclaimed slopes that are shallow as 12 degrees. Several detailed slope studies were conducted at the mine in the early 1970s. These studies, combined with more recent geotechnical investigations, provide a unique detailed history of pit slope failures on shallow slopes. This paper presents an evaluation of the slope failures at the Shirley Basin mine, highlighting important mechanisms causing slope failures on very shallow slopes. The evaluation demonstrates important key parameters for shallow slope design.

Jan 1, 2001

By L. Nahai

THE OUTPUT ff the mineral industry in 1964 in both non-Communist and Communist Europe showed an upward trend for most countries in keeping with the higher index of overall industrial production. Comparable indexes of mineral industry production for non-Communist and Communist Europe (including the U.S.S.R. in Asia) are not available, primarily because the U.S.S.R. does not report details of its industrial production by industrial sectors. However, available data both in the form of index numbers on production published by the United Nations and based on data as reported to the United Nations by the various countries, and actual production data for selected major commodities published by the various European countries reflect generally expanded output by both the extractive sector and the processing sector of the mineral industry in most of the 26 nations of Europe.

Jan 1, 1966

By Jiwen Zhang

Due to the blocking nature at the crusher station, straightforward application of queuing theory cannot give realistic results on the performance of a shovel-truck-crusher system. A new queuing network-based model has been developed in which, the crusher station is formulated into an open queuing network and the whole shovel-truck-crusher system into a closed queuing network with the crusher station as a special server. To fully account for the influence of blocking, Monte Carlo simulation is first used to obtain the performance parameters of the open queuing network for the crusher station. The closed queuing network for the entire system is solved by applying the Extended Summation Method (ESUM), in which the crusher server is described by the simulation results. The model has been applied to the Yuanbaoshan open-pit coal mine to analyze its shovel-truck-crusher system and to improve its efficiency. Results indicate that the blocking at the crusher is an important factor affecting the crusher output and in turn the efficiency of the whole system, and prove that the model can realistically describe the behavior of such systems.

Oct 1, 2009

By Frank T. Greene

An investigation of the quenching behavior of coal dust-air flames was carried out. The literature relevant to coal dust-air flames was reviewed, including information on the agglomeration, sedimentation, and dispersal of dust clouds. The simple equations relating the various concentrations involved in dust flame propagation are given and their implications elaborated. It is shown that the concentration seen by a moving flame in a sedimenting dust cloud can differ significantly from the concentration commonly measured in such experiments. The known dust cloud phenomena which appeared significant in flame propagation studies were experimentally evaluated, and quenching diameters, flame speeds, and lean propagation limits for several tube diameters measured. For Pittsburgh seam coal, the Minimum Quenching Diameter (MQD) for dust between 10 and 20 µm was found to be between 0.7 and 0.8 cm, and the lean propagation for 3.2-cm tubes to be approximately 200 mg/liter. Similar MQD data were also obtained for Pocahontas and Sewell coals, Beulah lignite, and a 50-gal./ton oil shale. The effect of temperature, coal particle size, and propagation tube material were also investigated.

Jan 1, 1981