Search Documents

By K. Lascelles

ABSTRACT Nickel compounds vary significantly in their toxicological properties, so it is critical that continuing studies to accurately quantify worker exposures consider the processing that accompanies refining nickel-containing materials. The Clydach nickel refinery, which has operated for more than 100 years, was the first nickel-producing facility to show a high risk for lung and nasal-sinus cancers among workers employed since it opened in 1902. Process chemistry and equipment have changed dramatically over Clydach’s history. This paper describes the processing evolution at Clydach with a focus on the propensity for aerosol formation and the forms of nickel in airborne dusts.

Jan 1, 2013

By R. W. Smith

The flotation response and electrokinetic behavior of Chlorella vulgaris and Chlamydomonas sp . when using dodecylamine hydrochloride as collector were studied in the absence and presence of Pb(I1). Also, an electron microscopy study was made of the algae after Pb accumulation. The flotation behavior of the organisms after Pb accumulation appears at least partially related to the location of the abstracted Pb onto or into the organisms.

Jan 1, 1991

THE Mining Methods Committee during the past year has spent much of its time developing the interest of members of the Institute in the work that comes under its direction. The response on the part of the membership has been most encouraging and in order to give a concrete form to the program which it hopes to develop, an "Outline for Papers on Mining Methods" has been drawn up and is herewith submitted for consideration. This outline has slowly taken shape until it now represents ideas contributed by a great many men, and it is hoped that it will be suggestive and helpful in the preparation of papers. This program can be used for the preparation of papers covering single large operations or, preferably, as the basis for a description of methods and the presentation of results obtained either in different districts or in different branches of the industry. The Committee presents this outline for the consideration of the various Sections of the Institute with the request that they will endeavor to interest the members of the Sections in covering comprehensively the mining operations with which they are connected. It is not the plan of the Committee to publish a paper on every mine, giving all the details outlined, but rather that an engineer familiar with a district prepare the general information and engineers of each important mine in the district compile the specific information of the mine with which they are connected. The general information and the specific information shall be sent to the Committee, and with this information the Committee will prepare a paper on the results obtained under the various mining methods in the different districts. The Committee requests that all papers shall be compiled under the direction of the Chief Engineer of the company and then submitted to the General Manager before acceptance for publication or compilation and tabulation with other similar data. Where the study of this subject approaches the fields of other standing committees of the Institute, the

Jan 5, 1922

By M. Sheedy

This paper discusses the short bed ion exchange technique for the removal of metal contaminants from copper electrolyte bleed streams. Processes for the selective removal of sulfuric acid, arsenic, antimony, bismuth, and iron will be discussed. A case study outlining the performance history of a short bed system for sulfuric acid removal followed by a two stage selective precipitation system producing a nickel carbonate by¬product at the Phelps Dodge Mining Company El Paso operation will be presented.

Jan 1, 2007

By G. Lyle

Since its inception CEMI (Centre for Excellence in Mining Innovation) has focused on facilitating innovative solutions to the mining industry in six strategic research areas; GeoRisk, ConstructMine, ValueMine, FindMine, SustainMine and MineTech (visit www.miningexcellence.ca for details). This paper focuses on CEMI?s largest project to date, Ventilation on Demand (VOD). Energy consumption in mines can account for upwards of 40% of a mines operating cost, with a significant portion of this been consumed by the ventilation requirements. VOD provides a significant opportunity to reduce overall mine ventilation requirements and subsequently energy costs, while potentially increasing mine productivity. CEMI is currently in year 2 of an assessment of VOD, focusing on the financial, physical and equipment viability of utilizing such systems in both new and existing mines. This two year program, to be completed by March 31, 2011, is designed to systematically assess such a system to determine if and when it could effectively be applied in underground mines. The paper will describe the process by which the project was initiated, the demonstration projects established to capture data, the means to interpret the data and the modelling developed to calibrate and predict ventilation system requirements.

Oct 1, 2010

air-lift and equipped with tapered tubing of proper design, we would have a gas input consumption of about 2500 cu. ft. per bbl., which at 3 to 4c. per 1000 cu. ft. would be 7 1/2 to l0c, per bbl., and there would be very infrequent loss of production due to stoppages. It has been demonstrated that with efficient design of air-gas lift, the production of wells can be increased much beyond that obtained with the former type of air-lift employed; also that small wells can be operated by air-lift with tapered tubing at a cost that places this method in competition with beam pumps in many fields. The next step in conservation that the writer expects to have an opportunity to demonstrate is that of restoring the pressure in a pool and producing by air-gas lift all of the oil possible to lift economically. This combined operation is probably the method toward which we shall eventually be working in recovering the maximum quantity of oil from pools where the oil is recovered through bore holes. General Discussion on the Air-gas Lift H. P. Porter, Tulsa, 0kla.—The papers presented at this meeting contain a great amount of valuable information. Wonderful progress has been shown in the development of air and gas-lifts. There has been nearly everything brought out that touches upon the subject. The real point that is lacking is exact knowledge of the velocity with in the flow column which will produce the best effect—that is the thing we must know more about. Velocity in Gas-lift Flow In other lines of industry the matter of velocity of fluids in pipe lines has been well analyzed and there are known laws by which to calculate velocity of flow; for instance, in irrigation work large pumps are designed with intake pipos to employ an intake velocity of 4 ft. per scc. By reduced cross-sect'ion the velocity is increased rapidly as it enters the pump and the discharge rate is at 12 ft. per src., which in turn is reduced in the discharge column to 4 ft. per sec. Crushed coal, grain and granular material is found to be best conveyed by air when a pneumatic conveyor is employed at 100 ft. per sec. As in the design of a pumping plant or a pneumatic conveyor, the velocity at the lower end of the column in the flowing well must be controlled within certain limits for best results. Mr. Griswold, I believe, stated that they had velocity as low as 15 it. per scc. and from that up to 78 ft. per sec. Mr. Pierce and Mr. Lewis showed an ideal flow column showing how the velocity increased as the fluid was carried up the column, hut did not give any figures as to the velocity. It would be well to take that sort of a diagram to establish an ideal velocity at the lower or intake end, and then calculate the velocity from expansion of the gas as it goes up. It may be that the, ideal intake velocity would vary, depending on the depth of the well, the quantity of liquid to be handled or the pressure which it may be desired to hold. The subject is one that might be worth much research.

Jan 1, 1928

By S. Harshaw, C. Doyle, A. E. M. Warner, D. Stremlaw

"In the Utility Nickel furnaces, the hearth and sidewalls are lined with high-Al2O3 bricks. During charging and thermal cycling (more so as the linings on these reverberatory furnaces age), pieces of brick spall or abrade from the refractory and collect on the top of the bath. These pieces are removed using a non-corrosive slag toward the end of the heat when the bath temperature is ~1600°C.This benign liquid can be generated by two methods. First and most obvious, suitable ingredients can be pre-mixed so that the flux (flux A) is isochemical with the non-corrosive slag. All that is needed to produce this targetted slag is heat. Second, in other proportions (flux B), the pre-mixed ingredients generate a corrosive slag that melts completely at -1200 °C and corrodes some but not all of the brick particles on the bath surface. As the reaction progresses, the slag changes composition eventually attaining the targetted benign composition. Using this option, additions are monitored to avoid overfluxing. In both cases, the generated slag/brick mixture can then be rabbled from the furnace. This practice has been successfully used for over two years and has been a factor in extending Utility Nickel furnace life to its current levels (about25% increase)."

Jan 1, 1993

By T. Tafi

The Ute-Ulay project area is located approximately five miles west of Lake City, in Hinsdale County, Colorado. The Ute-Ulay Mine site is approximately one mile east of the project area. The elevation of the site is 9,200 feet and is adjacent to Henson Creek (Figure 1) [ ] The Ute-Ulay Mining complex is an inactive gold, silver, and zinc mining/milling operation, that operated from the 1880?s until the 1970?s, and sporadically into the late 1990?s. The mining complex comprises several levels of underground mines, a flotation mill, and an abandoned town site. Due to the narrow, steep sided canyon, milled tailings were pumped upstream one mile in a sluice box to a wider section of the canyon, and deposited into five tailings impoundments and one berm located between the impoundments. An estimated 9,000 cubic yards (yd3) of fine grained tailings were located in the impoundments adjacent to the creek. The Ute-Ulay project area consisted of the mill tailings impoundments located upstream from the historic mine.

Jan 1, 2011

By Lifeng Yang, Xiang Zhang, Liang Yuan, Yonghui Wang, Bing Hou, Mian Chen, Rixing Zhang

Large-scale hydraulic fracturing technique has been widely applied to the development of shale gas reservoirs, where the interaction between natural fractures and critical fracture zones has substantial impact on the propagation of hydraulic fractures. Therefore, it is of significant importance to understand and experimentally verify such mechanism. To reach this end, tri-axial fracturing tests were implemented on 400mm×400mm×400mm block samples collected from Longmaxi shale outcrops. The interplay between hydraulic and natural fractures was investigated during the tests, factoring in the role of pump rate in affecting the created fracture network. Based on the experimental results, the critical fracture zone, defined as the weak formation zone nearby the wellbore created by staged pressure implementation that is observed rapid fracture propagation upon next stage of pressure increase, was thoroughly investigated. The analysis illustrates that given the high brittleness of the shale formation, abundant critical fracture zones are generated around natural fractures with pressure building up at a relatively low pump rate. As the pump rate increases, hydraulic fractures initiate and come into play with critical fracture zones, implying emergence of a large number of micro-cracks. A changing pump rate modifies the way of interaction between hydraulic and natural fractures and the subsequent formation of fracture network. Long term fracturing fluid injection with relatively low pump rate below the activation of critical zones is suggested. Also proposed is appropriate timing when applying a specific pump rate that will contribute to the improvement of hydraulic fracture propagation.

Jan 1, 2015

By W. S. Weldon, R. M. G. Machunter

The use of spiral separators for the beneficiation of fine coal typically in the size range - 2+0.lmm is now well established process technology. Developments during the mid 1980's resulted in the production of cost effective, efficient large diameter coal spiral separators. Recent developments and research have been geared to optimise metallurgical performance, materials handling and equipment geometry of large diameter coal spiral separators.

Feb 24, 1997

By Benjamin W. Haynes

As part of the first-order assessment of potential manganese nodule processing reject waste materials, the Bureau of Mines estimated the physical and chemical characteristics of reject waste materials that would be generated from each of five potential process flowsheets. These processes were chosen because of their economic and technical feasibility for first-generation nodule processing. A brief description of the five processes is given to show process inputs and outputs, The physical characteristics are predicted based on land-based laterite processing where applicable, and where no land-based analog exists, on the basis of process chemistry. The probable chemical characteristics such as element content and compound form are tabulated for each process for 16 elements: As, Ba, Be, Cd, Go, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, TI, and Zn. These elements were chosen based on their presence on the toxic substance list of priority pollutants, EP toxicity criteria, and major and minor elements of economic importance (Co, Fe, Mn, and Mo). Physical and chemical analyses as well as results of the EP toxicity test of one industrially supplied pilot plant reject waste material are presented.

Jan 1, 1982

By Ki-Bok Min, Bona Park

"In spite of the applications of DEM models to emulate the elastic modulus, Poisson’s ratio and strengths of isotropic rock in laboratory scale, extensions to anisotropic rock and larger engineering scale still have many challenges to overcome such as robust verification and validation against observed field case. In this study, a discrete element modeling was performed in order to represent a transversely isotropic rock such as shale, and the upscaled model was applied to foundation and borehole problems using PFC2D. The applicability of the upscaled rock mass model was verified by an analytical solution. The DEM modeling of stress redistribution induced by an applied surface line load compares well with Boussinesq’s isotropic solution and anisotropic solution given by Bray. The borehole model with a circular opening under biaxial stress was compared with both isotropic and anisotropic solutions resulting in good agreement. The abilities of DEM model to investigate the micromechanisms accounting for complex macroscopic behaviors and to predict the macroscopic behavior are discussed.The results demonstrate that DEM modeling has the potential to be applied to anisotropic rock mechanics problems on larger engineering scales such as wellbore stability problems especially in shale formations. Furthermore, the effect of anisotropy modeled through this study may be able to explain failure behavior of anisotropic rock encountered frequently in real cases.INTRODUCTIONAnisotropy is prevalent in various types of rocks, especially in shale that contain a set of parallel bedding planes. These weak planes in various forms are sources of large deformation and low shear strength and contribute significantly to the anisotropic behavior of rocks (Amadei, 1996; Cho et al., 2012; Kim et al., 2012). As elastic and strength behavior of anisotropic rock is substantially different from that of isotropic rock, proper consideration of anisotropy is of great importance. There is extensive of experimental evidence showing the anisotropy of shale. Niandou et al. (Niandou et al., 1997) analyzed the plastic deformation and failure mechanisms of Tournemire shale were highly dependent on the orientation of bedding planes. Cho et al. (Cho et al., 2012) presented various deformations and strengths of Boryeong shale obtained from laboratory experiments. Fjaer and Nes (Fjaer and Nes, 2013) performed uniaxial and triaxial compressive strength tests using Mancos shale, and they observed that the shear sliding along the planes of weakness before the occurrence of a major failure can reduce the strength of anisotropic rock. The recent research has demonstrated that the anisotropy of rock is an important consideration in rock engineering."

Jan 1, 2015

By T. Ertekin, X. Dong

This paper identifies the need for the development of specialized inverse solution techniques for the analysis of pressure transient data for the characterization of the transport and sorption properties of coal seams. Central to the proposed inverse solution technique is a specially structured artificial neural network (ANN). The most important transport and sorption characteristics of coal seams are butt and face cleat permeabilities, macropore porosity, Langmuir volume constant, Langmuir pressure constant, and sorption time constant. Conventional methods, such as type curve matching techniques and laboratory-derived measurements are handicapped in terms of being representative over the entire domain of interest. In this paper, we utilize analytical forward solution techniques for various combinations of characteristics of coal seams to generate training and testing patterns. These training patterns are shown to an ANN structured to learn the ubiquitous non-linear relationships that exist between coal seam properties, input conditions and the pressure transients measured. The trained networks are then extensively tested to ensure that they have effectively learned the training patterns. In the final stage of the development, the networks are run in the prediction mode. The responses of the networks are found to be in agreement with the input data. The developed networks are able to generate results generally within 5% error margin for permeability and porosity and 20% error margin for the sorption characteristics of coal seams. A number of examples highlighting the capabilities and degree of effectiveness of the network in characterizing the coal seams areincluded. Keywords: artificial neural networks (ANNs); coal seam characteristics; pressure transient analysis

Jan 1, 2003

By D Craw, P Upton

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Southern Alps of New Zealand and the mountains of Taiwan are both young transpressive orogens characterised by rapid uplift and exhumation, high heat flow and vigorous surface processes. Comparing and contrasting the two provides an ideal framework through which to explore the structural and lithological controls on fluid and gold mobility during collisional deformation. Both have two fluid flow systems centred about their drainage divide with shallow topographically-driven meteoric water above a deeper flow system dominated by mineralising rock-exchanged fluids. Despite similar tectonic settings, the distribution of heat flow, hot springs and veins in the two orogens are different. Taiwan has higher heat flow, distributed hot springs and localised veining whereas the Southern Alps have a narrow heat flow anomaly, localised warm springs and widespread veining. We use three-dimensional numerical models to evaluate key parameters that affect fluid flow and gold mineralisation. Models show that differences in crustal strength and thickness affect the locus, scale and rate of crustal fluid flow and hence influence gold deposition at a variety of scales. We explore how surface topography can lead to localised changes in the stress state, facilitating the switching of principal stresses and hence vein orientations.CITATION:Upton, P and Craw, D, 2015. Modelling structural and lithological controls on the mobility of fluids and gold in orogenic belts – examples from New Zealand and Taiwan, in Proceedings PACRIM 2015 Congress, pp 189–192 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Isabelle Demers, Audrey Jalce

L’industrie minière génère chaque année une quantité considérable de rejets miniers, principalement sous forme de stériles ou de résidus de l’usine de traitement. Les stériles sont des roches sans valeur économique, excavées pour atteindre la roche minéralisée. Ils sont usuellement empilés en surface formant des haldes à stériles. Les résidus miniers sont des roches finement broyées, mélangées avec de l’eau, résultant du traitement du minerai. Ils sont généralement pompés et entreposés en surface dans des parcs à résidus. Cependant, leur stockage peut être sujet à des instabilités géotechniques, mais également géochimiques, pouvant entrainer des problèmes environnementaux majeurs, tels que le drainage minier acide (DMA). Le DMA se produit lorsque des minéraux sulfureux, contenus dans ces deux types de rejets, s’oxydent au contact de l’eau et de l’oxygène [1]. Le DMA se caractérise par une solution acide (pH inférieur à 6) riche en métaux, contaminant les eaux souterraines et de surface et représentant alors un danger pour la faune, la flore et la santé humaine [2]. La remise en état et la fermeture des sites miniers doivent donc être pensées dès la phase d’étude du projet d’exploitation, afin de proposer une méthode de gestion des rejets qui permettra de limiter les impacts environnementaux pendant et après l'exploitation.

May 2, 2024

By C. B. Manula

This report is volume 9 of an eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment. The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation,' and ventilation. This volume of the final report describes the Water Generator subsystem of the Master Design Simulator. This subsystem simulates the flow of water through a typical watershed-reservoir combination to predict mine drainage quantities in underground workings. The model is a integrated one which handles both the unsaturated and the saturated flow domains as a unified system. The solution of the model is achieved by numerical tech¬niques of finite difference method coupled with finite elements analysis. The Water Generator can be operated either as a free standing model or in connection with the Geology and Reserves subsystem as a part of the Master Design Simulator. A case study is included illustrating the application of the model to actual data. The appendices of the report constitute a user's manual for the program, and include a program listing.

Jan 1, 1975

By E. R. Spencer, E. R. Bauer

Previous studies and research efforts have shown that noise-induced hearing loss (NIHL) is a problem in the U.S. mining industry. In response, researchers at the National Institute for Occupational Safety and Health (NIOSH) have been conducting a cross-sectional survey of equip­ment noise and worker noise exposures in the mining industry to estimate the potential for NIHL within the mining community. One commodity recently surveyed was the extraction of sand and gravel from surface pits and by dredging. To address the potential for NIHL in the sand and gravel industry, sound levels on and around the dredges and processing equipment were recorded to iden­tify areas of high noise levels. Full-shift worker dosimetry, in conjunction with task observations, was documented to determine the relationship between exposure and source. This paper presents research examining noise on dredges used in several surface mine sand and gravel operations and in the processing facilities. Results indicate that there are areas on the dredges (crane, suction pumps and diesel engines) where sound levels greater than 90 dB(A) are pres­ent. In addition, crushers and screens used in the processing of the sand and gravel also generate sound levels greater than 90 dB(A). Although no surveyed worker exceeded the Mine Safety and Health Administration’s (MSHA’s) permissible exposure level (PEL) of 90 dB(A) eight-hour time-weighted average (TWA8), laborers, mechanics, oilers, helpers, pickers and greasers are the workers most likely to be exposed to hazardous sound levels and to thus develop NIHL over time

The objective of the mission was basically to study the utilization of engineers and engineering technicians and their interrelationship in the Soviet Union. Beginning with their graduation from the engineering institutes and technicums, we hoped to learn how the graduates started out in industry, what their training on the job was, what sort of work they did, and how they worked themselves up within their profession. However, it turned out that, as our host was the Ministry of Higher and Secondary Education, most of our visits were to educational establishments. Our itinerary covered Moscow, Leningrad, Kharkov, Rostov, Baku, and Tashkent, with a side trip to Samarkand. In all, we visited 13 technical institutes, three technicums, and five industrial plants or enterprises, as they are called there. Our trip was one of only four weeks. Our observations were limited by the few cities and enterprises we were permitted to visit. Nevertheless, we did come back with some definite impressions and conclusions which we feel should be of interest to engineers, educators, and those concerned with the relative economic and technical power of the USSR and the U.S.

Jan 9, 1960

By Yanxu Shen, Cheng Liu, Zhijie Chen, Hao Chen, Huimin Gao, Zijie Ren

Fluorite, a kind of critical non-metallic minerals, is the primary source of industrial fluorine. Sodium oleate (SO) is commonly used as the collector of fluorite ores. However, because of its some features (such as the low solubility, high solidifying point, and poor dispersion of SO) at low temperatures, it profoundly inhibits its collecting ability as well as the flotation performance. Herein, we have developed a low-temperature-resistant collector for the efficient flotation separation of fluorite from quartz. The advantages and disadvantages of the SO and sodium petroleum sulfonate (SPS) were analyzed by comparing the performance under different temperature conditions. The results of flotation tests suggest that SPS exhibited much better collecting performance than SO under low temperature. The flotation mechanism of the two collecting agents were further analyzed by contact angle measurements, zeta potential measurements, Fourier-transform infrared spectroscopy (FT-IR), and flotation kinetics. The results indicated that both collectors can selectively undergo electrostatic and chemical adsorption with fluorite, with no adsorption on quartz surface. The sulfonic acid group in SPS is a hydrophilic functional group, which has a relatively higher solubility in water. Therefore, the water solubility of SPS is better at low temperatures.

Sep 30, 2021

By H. Groeneveld, C. A. Connally, P. J. Hoenmans, W. L. Mason, John J. Justen

"A miscible displacement pilot, using a slug of LPG driven by separator gas, was conducted in the Cardium Reservoir of the Pembina Field. The injection pattern was a 10-acre, inverted, isolated five-spot. Upon completion of the LPG-gas phase, an .experiment was conducted using a slug of water followed by gas. Calculated performance of the pilot is compared with actual performance. Equations are developed to cakulate the distribution of LPG into zones of varying permeability, to estimate the progress of the flood at different times in the various zones, and to estimate gas rates after breakthrough. The analysis indicates that permeability stratification was a dominant factor in con-trolling oil recovery and that oil was completely displaced from the swept pore volume. The results of the pilot indicated that miscible flooding is a practical means of pressure maintenance in this reservoir. The total recovery from the pilot area was good in spite of the early breakthrough of LPG. The effects of stratification were reduced by injecting a slug of water into the partially swept reservoir."

Jan 1, 1960