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By M. J. Rex, K. L. Wiley, D. S. Ramey

In situ leaching, initiated in 1986 at the San Manuel Mine, was economically developed in 1989. The primary reason for this lag time between startup and viable production was the time required for technical development. The technical development pursued comprised detailed design, development and implementation of in situ well construction methods, formulation of suitable well pattern arrays and the development of extensive hydrogeologic and geochemical knowledge of the mineral deposit. Since 1989, the in situ leaching program has become a viable and cost-effective method to extract copper from the supergene mineralized zone of the San Manuel deposit. The in situ leaching methods that are currently used have been progressively expanded and continually developed. They will become the cornerstone of copper production from the San Manuel oxide mineral deposit. This paper presents an overview of the supergene hydrogeology, current design techniques, drilling methods and well completion, pump determination and setting, solution management and future plans for the increased extraction of copper by in situ leaching methods at the San Manuel Mine.

Jan 1, 1995

By Robert M. Becker

This investigation (in five parts) extends the theory of sample reliability from a sample consisting of a fixed number of items to a sample consisting of a fixed amount of items. Examples of a fixed amount of items per sample are samples consisting of a fixed weight or a fixed volume of unequal size particles. The extension of the theory is confirmed by experimental laboratory sampling using standard procedures. The probability distribution functions (the binomial, hypergeometric, multinomial, generalized hypergeometric, and those here called the compound binomial and compound multimomial functions) are developed from fundamentals. Their distributions are generalized to include some measured characteristic of the items. Infinite population moments are derived from moment-generating functions, and finite population moments are developed from corresponding infinite population moments using a newly defined mathematical operation. The first three experimental moments in laboratory sampling to given weights of particles are compared with the theoretical moments of their corresponding compound mult.inomial distributions. The agreement is striking. The study is divided into five parts. Part 1 deals with probability or random sampling to n items and with all sampling to n items per sample from some one probability distribution. This is the area of sampling covered by well-known theory. Accordingly, the procedures may be different but many of the results are well known.

Dec 1, 1964

By D. C. McIntire

The Homer City Station, jointly owned by New York State Electric and Gas Corporation and Pennsylvania Electric Company is a three unit coal fired station. The first two units were put into commercial operation in 1969; the third unit became commercial in 1977. Units 1 and 2 are subject to the Pennsylvania State Implementation Plan (SIP) emission limit of 3.7 pounds of S02 per million BTU. Unit 3, having started construction later, is subject to the Clean Air Act, New Source Performance Standards emission levels of 1.2 pounds of 50-2 per million BTU.

Jan 1, 1988

By W. A. Eardley

FIFTEEN years ago the world's deepest oil well penetrated the earth about 7300 ft. That depth has now been more than doubled. Why has such deep drilling become necessary and how has it become possible? Three factors have had an important bearing: (1) Depletion of shallow zones, making it necessary to search for deeper producing measures. (2) The perfection of prospecting methods, which have been success- fully used to locate favorable buried structures, many at great depth. (3) Improvement in the quality of steels used for drilling.

Jan 1, 1940

By Sayavur Bakhtiyarov

Keywords: Rheology, Viscoelastic, Oil In this paper we present the results of the rheological property measurements on viscoelastic composite materials used in oil industry. Laboratory experiments were carried out to determine important thermophysical, rheological and mechanical properties of the test materials using both the standard commercial and in-house made equipment. The composites with the paramagnetic particles (?-iron oxide) are exhibited a significant magnetic memory after magnetic treatment. The measured value of the yield stress after the magnetic treatment increased almost twice in comparison with the yield stress value of the magnetically untreated composite. The yield stress of the composite material exponentially decreases with time and reaches its magnetically untreated value after 15 hours. The yield stress also increases with the amount of the paramagnetic powder additive, and it reaches a maximum value at 8 wt-% of this additive. The obtained results provide valuable information for computer modeling of the viscoelastic fluid flow in pipes of complex geometry.

Jan 1, 2005

By N Mangadoddy, P Jampana, S Diddi

The study of air-core dynamics in hydrocyclone operation is essential for predicting separation efficiency in mineral processing. Electrical resistance tomography (ERT) allows non-invasive measurements of hydrocyclone internal flow dynamics. Existing regularisation methods such as Gauss-Newton and TV norms rely on optimisation techniques which have very high computational cost for very fine meshes. In contrast, the monotonicity method has much lower computational cost as it does not solve such minimisation problems. In this paper, results from the monotonicity method, Gauss-Newton (GN) (Tikhonov) and Total-Variation (TV) norm-based minimisation methods for estimating the air-core diameter in hydrocyclones are compared. We study these methods on the laboratory hydrocyclone experimental two-phase flow data. The results obtained are validated against High-speed video (HSV) imaging and Computational Fluid Dynamics (CFD) results. The results on different mesh sizes, in particular for very fine meshes with the number of cells ranging from 30 000 to above 100 000 are also investigated. The data used in this study is obtained from ITS Z8000 ERT system. This system does not measure the voltages on the current carrying electrodes. Since these voltage values are required for the monotonicity method, we implement an interpolation method to compute them. The results show that the monotonicity method provides a closer approximation of the interface between air and the water phases.

Aug 24, 2022

By John F. Kearney

Labrador Iron Mines (?LIM?) Schefferville Projects consist of 20 major DSO deposits lying along a 120 km strike length in both the provinces of Newfoundland and Labrador and in Quebec. The town of Schefferville, Quebec lies close to the middle of this 120 km strike. LIM?s various properties comprise twenty different iron ore deposits which were part of the original Iron Ore Company of Canada (?IOC?) direct shipping Schefferville operations conducted from 1954 to 1982 and formed part of the 250 million tons of historical reserves and resources previously identified by IOC. LIM intends to develop all these resources in five separate stages. The first four stages will see the various deposits treated in three beneficiation plants, to be built adjacent to several of the deposits that comprise the Central, South Central and North Central Zones. The final stage is not yet planned but will likely involve a fourth plant. A Feasibility Study has not been completed on any of these Projects. LIM plans the development and mining of the various deposits in separate Stages. It should be noted that only the James and Redmond deposits have been permitted. All other deposits require environmental assessment and permitting. Only the James and Redmond deposits have been subject to detailed mine design. The Houston deposit has had preliminary mine design carried out. All other deposits will require detailed mine design when further geological data is collected and compiled. Detailed metallurgical testwork has been carried out on blue ore from James, Houston, Redmond and Knob deposits and to a more limited extent on yellow and red ores from these deposits. Only limited review work has been carried out on the high-silica blue ores. All of this work will be needed to be complete to confirm the final process routes. Additionally some metallurgical work will be required to be conducted on each of the other deposits to characterize their metallurgical response and to confirm expected recovery levels. Detailed mine design and metallurgical testwork has been carried out on those deposits that will form the basis of production for the initial years but further exploration, testwork and design is required for all the remaining resources. The first plant at Silver Yards and mine construction at James are now complete and initial production is expected in the spring of 2011. Metallurgical testing of the first stage deposits has established that the ore can be successfully upgraded to marketable standards. Based on the current testwork, a program of plant enhancement on the Silver Yards plant is now planned with the objective to increase both the plant throughput and recovery. Production of direct shipping lump ore and sinter fines is forecast at around 1.5 million tonnes in 2011 and, based on current and historical resources, growing to approximately 5 million tonnes in 2015 and thereafter. Production from the first four stages is expected to continue at about this rate through to about 2028.

May 1, 2011

By K. Best, D. Conn

The US Army Corps of Engineers KY Lock Project in western Kentucky presented the blasters and vibration consultants with a set of unique challenges. The blasters on this project were faced with difficult geology and joint set orientation and sequencing of blasts opposite from what the explosive engineer/blasting specialist had recommended. Combining these issues with strict vibration and air overpressure specifications, blasting as close as 7 feet (2.1 meters) from a new lock wall, site topography that influenced the air overpressure, limitations on seismograph geophone placement that led to anomalies in seismograph recordings; surprising lessons were learned by everyone involved in the project and it is the authors’ goal to share this valuable information with everyone in the blasting industry.

Jan 1, 2024

By Dong Hoon Han

The sulfation rates of magnesium oxide and calcium oxide (molar ratio 7:3) contained in calcined CMA ( calcium magnesium acetate) by SO2 were measured. The experiments were carried out in the temperature range 700 to 1100 °C and under the SO2 concentrations of 0.3 to I mol % (5 % 02). In the low-temperature range below 830 °C the reaction produced CaSO4.3MgSO4 and unreacted MgO, but no MgSO4 phase. The formation of CaSO4.3MgSO4 phase has a significant implication in that it allows the utilization of MgO for SO2 removal whereas the sulfation of MgO from conventional sources is so slow that it is of no practical interest. Thus, the calcined CMA can remove SO2 at lower temperatures than conventional SO2 absorbents and at a greater capacity. Above 950 °C only CaO reacts with SO2, but at a much greater rate than the calcined Ca(OH)2, which is one of the most reactive SO2 absorbents.

Jan 1, 1998

By Davis M. Lapham

Ore bodies at Cornwall, Pennsylvania, have been mined since 1742 principally for iron from magnetite, but also for copper (in chalcopyrite), silver (in chalcopyrite), gold (in chalcopyrite), cobalt (in pyrite), sulfur, and crushed limestone aggregate. Metallization occurs as a limestone replacement above the essentially conformable, south dipping portion of a discordant saucershaped diabase sheet. Pre-Triassic and Triassic faulting have emplaced host Cambrian limestone and two Ordovician(?) hornfels units, now for the most part resting above diabase. Thermal metamorphism of carbonate-bearing country rocks largely to calc-silicates, is ubiquitous. Metasomatism, particularly of potassium, is unique to ore zones. Associated magnetite- actinolite mineralization replaces, in a preferential sequence, all earlier metamorphic and metasomatic minerals and rarely diabase chilled margin. Mineralogical (diopside, actinolite, mica, sulfides, oxides) and chemical (Fe, Cu, S, Co) zoning of the eastern ore body is focused down dip, near its western edge, along a major vertical fault through diabase. This zoning is spatially related to magnetite veins in diabase, to an ore body within diabase, and to a shear zone that probably extends through the sheet.

Jan 1, 1968

By Stefan Mutl

By the term sorting one understands the separation of a material mixture into two or several products according to different material characteristics in the preparation technology. The oldest sorting procedure, the handpicking, is less and less used to separate different material mixtures because of the considerable personnel expenditure and the strict hygienic regulations at the workplaces in Europe. In general, the manual assortment is able to solve separation tasks, which could not be solved by machines so far. The picking is one of the most selective processing methods. However, the progress in the computer and sensor engineering today makes the creation of automatic picking devices possible, whose efficiency goes far beyond the possibilities of handpicking. Therefore in the future automatic picking will not only be applied to already common applications like the waste glass assortment by colour, but also to the assortment of complex composed material mixtures e.g. old shreddered cars. Thus, the automatic picking, supported by high performance computer systems and new sensor technology, gains more and more significance within many applications of waste processing. However, in order to apply automatic sorting procedures for different material streams within recycling processes, a substantial research and development need still is existing. The desire of the users is to sort more extensively in order to achieve products with bigger material varieties, In addition, the requirement of the accuracy of recognizing and sorting out of single grains rises, This lecture illustrates the procedure of the hand picking before it was employed in waste processing. Thus, a renaissance of a long forgotten method is happening in terms of today's state of the art procedure "automatic picking". Possible technologies, fields of application and future potentials of this technology are pointed out.

Jan 1, 2003

By George A. Komadina

Pima Mining Company has recently completed their expansion tripling the plant capacity to 18,000 tons per day and now is in the process off expanding to 30,000 tons per day with completion scheduled for the summer of 1967. This paper briefly discusses the additions to the mining department and support areas with a more detailed report on the complete new crushing plant and additions to the concentrator. The crushing plant includes a 54-inch gyratory crusher, three 7-foot standard and seven 7-foot short head crushers along with necessary screens, feeders, and conveyor belts to produce a minus 1/2-inch rod mill feed. The concentrator consists of ten milling sections, each containing one 10-foot by 16-foot rod and two 10.5-foot by 13-foot ball mills, classification is done with cyclones. Pulp from each section is floated in 50 cells of 66-inch Fagergren flotation machines to produce a rougher concentrate which is cleaned in six stages of Denver cleaners to produce a final concentrate The various mill products are thickened with disposal made in conventional manner. Plant instrumentation is discussed in the paper.

Jan 1, 1967

By James M. Neilson

In contrast to the rather generalized title of this paper, the subject of discussion will deal with two specific cases of sliding in glacial lake clays in northern Michigan. The slides in question occurred on lands owned by the Upper Peninsula Power Company a short distance south of Lake Superior. Slope failure problems have plagued the Company's operations for many years. It is hoped that this paper may provide some insight into the causes and possible mechanisms of clay slides in general as well as providing details of the two slides specifically cited. LOCATION The Upper Peninsula Power Company's Victoria facilities lie in section 29, T. 50 N., R. 39 W., in Ontonagon County, Michigan. The power site is situated on the West Branch of the Ontonagon River, approximately five miles southwest of the town of Rockland and only one mile to the southeast of the old mining location of Victoria. The area lies wholly within the Precambrian Shield and it is geologically similar to adjacent parts of Wisconsin, Minn¬esota, and Ontario. (Figure 1). THE VICTORIA HYDROELECTRIC SITE The Victoria hydroelectric power facilities were constructed in 1930 on a portion of the West Branch where meanders are conspicuously developed. The generating station is actually sited on an abandoned meander at a place where valley widening has occurred. Water is conducted from Victoria Dam through a 6000-foot, 10-foot diameter wood stove pipe - through a surge tank - and into the powerhouse where

Jan 1, 1971

By Charles Goodeve

"BEFORE I begin, I should like to thank The Canadian Institute of Mining and Metallurgy for the honour they have bestowed in inviting me to give this address at the fourth annual C.I.M. Conference of Metallurgists banquet.Secondly, I should like' to convey the greetings of the Iron and Steel Institute of Great Britain in accordance with a request made by its Council at its last meeting. The I.S.I. hopes for the continued growth in strength of this annual Conference and in the collaboration between our respective societies.When I read the program of this Conference, it was brought home to me what a non-ferrons country Canada is. Also, I realized what enormous advances have been, and are being made, and what an ex-citing field non-ferrous metallurgy is for the scientist. This made me wonder, as I have done before, whether the future for steel was proof against these advances.At present, iron and steel stand astride the metallurgical world like a Colossus; I hope that the bronze industry will pardon my stealing their thunder and mixing my metaphors! Will this still be so in the future?The best way to answer this question is to take a look at the fundamentals to see why the iron atom dominates to such an extent that al! other metals are called ""non-ferrons."" Is its present position due to historical and therefore ephemeral reasons, or is there a fundamental difference between the atom of iron and those of other metals?"

Jan 1, 1966

By Chaojun Fan, Du Wenzhang, Sheng Li, Hong-Hong Shi

"Coal and gas outburst is an extremely complex dynamic disaster in coal mine production process which will damage casualties, equipment facilities and disorder the ventilation system by suddenly ejecting a great amount of coal and gas into roadway or working face. This paper analyzed the interaction among the three essential elements of coal and gas outburst dynamic system. A stress-seepage-damage coupling model was established which can be used to simulate the evolution of the dynamical system, and then the size scale of coal and gas outburst dynamical system was investigated. Results show that the dynamical system is consisted of three essential elements, coal-gas medium (material basis), geology dynamic environment (internal motivation) and mining disturbance (external motivation). On the case of C13 coal seam in Panyi mine, the dynamical system exists in the range of 8-12 m in front of advancing face. The size scale will be larger where there are large geologic structures. This research plays an important guiding role for developing measures of coal and gas outburst prediction and prevention. INTRODUCTIONCoal and gas outbursts are a complicated mine gas dynamic phenomenon that pose a serious threat to coal mine safety production. Since the first recorded coal and gas outburst occurring in Isaac coal mine of the Lule coal field in 1843, more than 40,000 outbursts have occurred in the world. China ranks first in outburst frequency and intensity. In recent 20 years, China on average increases 37 pairs of coal mines and more than 280 times outburst accidents every year (Yan, 2013). The coal and gas outburst occurred on Oct 20, 2004 in Daping Coal Mine, Zhengzhou Coal Group, caused serious gas explosions and ejected 1,894 tons of coal into the face, causing 148 fatalities. In recent years, despite implementation of numerous control measures, coal and gas outburst still occur frequently ash mining depth and mining intensity increase. The outburst mechanisms can be summarized in the following four aspects: the gas leading role hypothesis, the geostress leading role hypothesis, the chemical effect hypothesis, and combination hypothesis. The last hypothesis has won the acceptance of most scholars who consider that an outburst is the result of combined effect of stress, gas and coal (Yu, 1992).Numerous experimental measurements and numerical simulations were conducted to investigate the permeability and damage development process in coal seam. Sobczyk, et al (2011) carried out a laboratory research of the influence of sorption processes on gas stresses leading to coal and gas outbursts. Wang, et al (2013, 2015) conducted laboratory experiments to investigate the rapid decompression and desorption induced energetic failure in coal using a shock tube apparatus. Xu, et al (2006) developed a coupled gas flow and solid deformation numerical model and applied to simulate the coal and gas outbursts in underground coal mines using RFPA2D-Gasflow. An, et al (2013) and Xue (2014) analyzed major parameters and the effect of gas desorption on outburst initiation and established a model of gas migration and mechanical processes during excavation."

Jan 1, 2016

By D. Akers, R. Dospoy

Introduction The geological processes that form coal can also concentrate trace elements in the coal. For example, the average concentration of arsenic in bituminous coal (20 ppm) is ten times the average concentration found in all the other rocks that make up the earth's crust (2 ppm). Similarly, other elements, such as antimony, cadmium, mercury and selenium, are more concentrated in coal than in the earth's crust. When coal is burned, trace elements can be further concentrated. Although no new constraints on trace clement emissions were placed on the power generation industry under the 1990 Clean Air Act Amendments, the act does mandate a three-year study of air toxics. Any new regulations aimed at electric utilities as a result of this Federally-mandated study will almost assuredly be very costly-an estimated $1 billion per year. Many trace elements in coal are associated with mineral matter. For example, arsenic is commonly associated with pyrite, cadmium with sphalerite, chromium with clay minerals, mercury with pyrite and cinnabar, nickel with millerite, pyrite and other sulfides, and selenium with lead selenide, pyrite and other sulfides (Finkelman, 1980). There are also cases in which some of these elements are organically bound. Just as both organic and pyritic sulfur can be found in the same coal, the same trace element may be both organically bound and present as part of a mineral in the sane coal. Physical coal cleaning techniques are effective in removing mineral matter from coal and can potentially remove at least some of the trace elements associated with specific minerals, thereby reducing the release of these elements into the atmosphere. Conventional coal cleaning to remove trace elements As part of a project funded by the Electric Power Research Institute, CQ Inc., a wholly-owned EPRI subsidiary located in western Pennsylvania, has demonstrated that large reductions in the concentration of many trace elements are possible if conventional coal cleaning techniques are properly applied. Four examples are given in Tables 1 to 4. In each example, the results shown were generated by cleaning the coal at CQ Inc.'s commercial-scale cleaning test facility. Cleaning results for Upper Freeport Seam coal from Northern Appalachia are provided in Table 1. Data are presented in the table in two ways: as a weight-based concentration (parts per million) and as a concentration per heat unit (grams per billion Btu). Grams per billion Btu is analogous to pounds per million Btu, but avoids the use of numbers with many decimal places. The heat-based concentration provides a better measure of boiler impacts, because the increased heating value obtained through coal cleaning reduces the number of tons that must be burned to produce a given thermal output. Reducing the quantity of coal burned reduces the quantity of trace elements entering the boiler. This raw coal is relatively high in several trace elements of environmental concern, including arsenic, cadmium and chromium. Cleaning provided large reductions in the quantity of arsenic, barium, cadmium, chromium, fluorine, lead, mercury, nickel, silver and zinc. The results for tests with a Powder River Basin coal, Rosebud/McKay, are presented in Table 2. Large reductions in arsenic, barium, cadmium, fluorine, mercury, nickel, selenium and zinc were observed with cleaning. The concentration of chromium increased with cleaning, while lead concentration increased in one test and decreased in another. Table 3 presents test results for Croweburg Seam coal from Oklahoma. Large reductions in arsenic, barium, cadmium, chromium and zinc were obtained with cleaning. Smaller reductions were obtained with lead and nickel, while chromium, fluorine and mercury increased in at least one of the tests. Table 4 presents cleaning test data for Kentucky No.11 Seam coal. In this case, large reductions were obtained with all elements measured. In general, these data indicate that physical coal cleaning is effective in reducing the concentration of many trace elements, especially if they are present in the coal at relatively high concentrations. The degree of reduction achieved is coal-specific, relating in part to the degree of mineral association of the specific trace element and the degree of liberation of the trace element-bearing mineral. The extent of trace element removal also depends on the method of cleaning the coal. Figure 1 is a washability plot, by size fraction, of arsenic vs. ash content for Upper Freeport

Jan 1, 1994

By Richard E. Barrett

SOME YEARS AGO I was associated with a mining operation which, because of its isolated location, burned wood for heating purposes. Year after year the tractors and tucks hauled the cordwood in from the edge of the ever-growing clearing. Each year the cartage costs became greater. The degree to which transportation distances affect the economics of fuels obviously varies with many factors, but the main criterion is the amount of heat a unit weight of the fuel will produce. For in-stance, wood is limited in most cases to a haulage distance of a few miles. Coal can be shipped hundreds of miles, whereas petroleum and gas ?can be transported thousands of miles. The world is now on the brink of having a new fuel -uranium. It has the virtue of being so concentrated that transportation costs can, for all practical purposes, be disregarded.

Jan 1, 1958

By D. K. Panda

The behavior of single drops with gas evolution at the interface is of interest because this is one of the important reactions that occur in oxygen steelmaking vessels, where a large amount of iron-carbon drops are dispersed in an oxidizing slag. The carbon dissolved in these drops, reacts with the slag to form CO, which is evolved as a gaseous phase. A room- temperature model was used to study the nature of this type of reaction including the effect of various factors such as viscosity and the presence of surface active impurities. Experiments were done for reacting drops over a wide size range to observe various regimes of behavior. Large single drops were levitated in a counter current flow to produce a sufficiently long residence time to allow the study of the various stages in the reaction. The emphasis of this work was to obtain photographic evidence of a high quality to describe all possible modes of behavior, and so a lot of effort was given to developing and perfecting experimental techniques.

Jan 1, 1994

By Robert A. Jankowski

"Following passage of the Coal Mine Health and Safety Act of 1969 (Public Law 911173), the Bureau of Mines initiated a research program aimed at controlling respirable dust exposures of coal mine workers. Respirable dust is the dust that gets into, and interacts with, the lungs of those who inhale it. It has long been recognized as a severe health hazard to mine workers. This program has been implemented by a team effort consisting of the Bureau's in-house capabilities, the Generic Center for Respirable Dust, and contractors, as necessary. Over the years, Bureau research has addressed principally three areas:o Compliance with the Federal 2.0 mg/m3 dust standard (1970-76).o Dust control for longwall mining (1976-1983).o More stringent respirable dust standards due to quartz dust (1983-1987).In addition, fundamental studies have been conducted by the Generic Center for Respirable Dust, with emphasis on penetration of dust into the lung. Accomplishments have been significant, but problems remain, as noted later.The Coal Mine Health and Safety Act of 1969, established a 2.0 mg/m3 dust standard for all coal mining operations, underground as well as surface. At the time of enactment of this legislation, the industry was averaging approximately 4.0 mg/m3. The Bureau of Mines respirable dust research program played a significant role in identifying and developing effective technology to allow better compliance with this new standard, thanks to industry implementation and Federal enforcement."

Nov 1, 1988

By Kent W. Hawley

An improved visibility system was developed for use on the large (100 ton+) haulage trucks typically operated in open pit and surface mines. The improved visibility system provides the truck driver' with a means of viewing hazardous situations that occur in the extensive blind areas adjacent to his true. The cost effective, reliable, visibility system consists of a closed-circuit television three unique fresnel viewers, and two improved mirrors. This report describes the visibility problems of Large trucks in the surface mining environment, shows the performance of existing mirrors, substantiates concept selection, and describes the prototype improved visibility system.

Jan 1, 1978