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An Integrated Solid Waste Management Method for Western Macedonia, Greece

Sep 13, 2010

By Walter T. Lewieki

"INTRODUCTION Numerous deposits of iron ore are found in Cherokee, Bartow, Floyd, and Polk Counties in northwest Georgia. The deposits are generally small and irregular in shape. The ore is usually referred to as ""brown ore"" and is predominately limonite. The crude or ""bank ore"" has to be washed and concentrated before being shipped.The proximity of the deposits to the Birmingham furnaces and a favorable freight differential permit the operation of many deposits that otherwise would be uneconomical. The district produced 413,468 long tons of brown-ore concentrates, averaging 45.53 percent iron in 1943.The necessity of developing additional iron-ore reserves for the war energeucy to supplement the production of the Birmingham district, prompted the Bureau of Mines to initiate exploration of the more promising northwest Georgia deposits. Thirteen properties in the four counties were explored during the program (fig. 1).HISTORY AND PRODUCTIONSeveral furnaces were operated in the district until the early 1900's, ranging from charcoal furnaces to more modern plants with capacities up to 50 tons of pig iron. No furnaces have operated for about 40 years, the product being shipped to Alabama and Tennessee.Bartow County iron mining is declining, although formerly it was the principal producer of the district. Most of the known merchantable ore deposits have been exhausted. For the past 3 years the Mitchell-Hodge mine has annually produced about 225,000 long tons of concentrates containing 46 to 43 percent iron and at present is the only large producer in Bartow County."

Jan 1, 1946

By Marko Lampi, Marc Nicolle, Janne Karonen, Kari Valkama

"In the ten years from 2003 to 2013 global mine production of copper has increased by over 23% to meet demand while the weighted average head grade has dropped from 0.9 to 0.7% Cu. These divergent trends of increasing demand and declining economic grades will extend the life of many existing mines and improve the viability of marginal and/or complex copper deposits. Against that context this paper outlines hydrometallurgical copper sulphide leaching options as alternatives to the more conventional pyrometallurgical processing route of copper sulphides. Three copper sulphide leaching and refining processes are discussed: total pressure oxidation, ferric sulphate leaching and copper chloride leaching. The effect of mineralogy on the choice of processing technology is discussed as well as some of the unit processes used. Additionally, possible benefits that a hydrometallurgical process may offer over an existing pyrometallurgical route are discussed. Subsequently, two very important aspects to the development of projects involving the leaching of copper sulphides are discussed. Finally, a number of conclusions are presented that will be useful to keep in mind when considering projects involving the leaching of copper sulphides. INTRODUCTION In the ten years from 2003 to 2013 global mine production of copper has increased by over 23% to meet demand while the weighted average head grade has dropped from 0.9 to 0.73% Cu (Murphy, 2014). If these divergent trends of increasing demand and declining economic grades continue, they will contribute to the extension in life of many existing mines and improve the viability of marginal and/or complex copper deposits. Against that context, this paper outlines hydrometallurgical copper sulphide leaching options as alternatives to the more conventional pyrometallurgical processing route for copper sulphides. Three copper sulphide leaching and refining processes are discussed: total pressure oxidation, ferric sulphate leaching and copper chloride leaching. Ferric sulphate leaching and copper chloride leaching are carried out at atmospheric pressure while total pressure oxidation takes place at elevated pressures."

Jan 1, 2015

By G. S. Littlejohn

In anticipation of the flooding of an adjacent dolomitic groundwater compartment, five rough parallel sided boundary plugs at 58 and 50levels have been designed to resist safely hydrostatic heads of 1500and 1250 metres, respectively, over a service life of 100 years. Following a description of the engineering properties of the surrounding rocks, the paper details the design considerations relating to structural length and strength, hydraulic gradient, rock mass watertightness, constituent materials of mortar intruded concrete, pregrouting of permeable discontinuities within the surrounding rock mass, a bentonite barrier to resist aggressive mine water, plug tightening and design performance requirements. Routine quality control tests include permeability of the rock mass, fluidity, bleed and strength development of the intruded mortar, and temperature of the intruded concrete during curing. A special test programme includes determination of strength and stiffness of cored concrete and rock samples, shear strength of the rock/plug interface and associated in situ contact stress in order toe stimate the load safety factor against plug failure by shear.

Jan 1, 2006

By Jim Ploger, Peter W. Johnson

Bus drivers represent a large segment of the US transportation industry and research has shown an association between exposure to Whole Body Vibration (WBV) and the high rates of low back disorders. Impulsive WBV exposures have been recognized as a risk factor for low back injury and new guidelines exist for their measurement and assessment (ISO 2631, Part 5). Methods to accurately and better characterize the impulsiveness of WBV along with the temporal patterns of the exposures are needed. The development of a hardware and software system to measure continuous TWA and raw, impulsive WBV exposures and the design of a subsequent study are presented. Methods Using two Larson Davis HVM 100 as accelerometer amplifiers, small external batteries, and a Pocket-PC (PDA) with 1 Gb of compact flash memory, we can collect up to 16 channels of data for a full day 600 Hz. Tri-axial WBV exposures will be measured and characterized at the frame of the bus and at the driver/seat interface (seatpad accelerometer). Using a repeated measures design, 20 bus drivers will drive on selected routes which include both city streets and highways, and within and between subject components of variability and exposure determinants related to the bus, bus seat, the bus driver, and the route will be identified. Global Positioning System (GPS) data will also be collected and integrated with the WBV exposure data to facilitate the identification of the location, velocity and type of road associated with high average TWA and impulsive WBV exposures. This system may be used to develop administrative (alter speed and/or route of bus, systematically vary type of routes) and/or engineering controls (identify and trigger the need for street repair) to reduce high WBV exposures. Results Our portable Pocket-PC based data acquisition system is up and running and we can collect seven channels of WBV data (seat pan tri-axial accelerometer, bus frame tri-axial accelerometer and GPS data) continuously for a full shift. The software analysis of the data is complex but nearing completion. We have incorporated the vibration dose calculations from ISO 5321, Part 5 and have obtained a Matlab-based routine to appropriately weight the continuous signals. Discussion In summary, the measurement of WBV is complex but new technologies open avenues of collecting and assessing WBV exposures that were previously not possible. The standardization of impulsive WBV exposure assessment methods is needed to further the discipline and better enable comparisons across studies.

Jan 6, 2006

By L. D. Johnson

On a project which is to develop a system to suppress coal dust explosions, a facility has been built and several devices tested. The facility is a 317-foot, 4.5-foot diameter shock tube and to date 53 tests have been carried out with methane-air and methane/coal dust-air as the explosive mixtures. Suppression of slowly propagating (up to 300 ft/sec) flame fronts has been successfully carried out on two tests using the dry chemical extinguishing agent Purple K. Delivery of the material directly into the flame front Seems to be required if effective suppression is to be accomplished.

Jan 1, 1972

By Andrew Wessman

Keywords: Recycling, Electrodeposition, Recovery, Dilute, Dissolved Metal Ions In order to facilitate the recovery of pure metals from solutions containing a mixture of dissolved metal ions, a pulsed electrodeposition method was developed. Using this method, it is possible to selectively remove metal ions from solution based upon the electrochemical potential of the particular ion desired. The use of pulsed electrodeposition rather than direct current electrodeposition creates an electrodeposited material with better morphology, increases electrical efficiency of the process, and avoids problems with short circuiting between electrodes. Using this method, it is possible to recover dissolved metal ions in a purified form in one simple step, and therefore maximizes recovery of the metal ions while obtaining them in a saleable form. This method is likely to be useful in improving the recycling process for numerous complex metal mixtures and alloys.

Jan 1, 2005

By E. R. Darby

When bronze is melted in open-flame furnaces a considerable amount of slag is formed during the melting operation. This slag may be incidental to the melting practice or it may be formed intentionally by slag-forming constituents added to the furnace charge to provide a covering for the melted metal When this slag is removed from the furnace, it contains, in addition to the free metal carried with it by the skimming operation, a considerable amount of metal as oxide either combined or mechanically mixed with it. By the usual crushing and washing methods this metallic oxide generally goes to the tailings pile, so diluted by other foundry waste that its recovery is economically impossible. If this furnace slag is not inixed with other foundry waste, practically all of the metal oxide as well as the free metal may be recovered by some form of smelting operation. The first side of the problem to be considered is the amount of slag produced. It may not be true that the majority of foundries have no record of the amount of slag made, but it is certainly true that a very great many either have no record or pay little attention to it. Usually the collection of furnace slag for one normal week's run will be sufficient to determine the advisability of its being handled in a different manner from the crushing and concentrating generally employed. If a large representative sample of the accumulation is crushed and concentrated and the recovery compared with the results of a careful assay, it will be found that a large percentage of the total metal content was lost in the washing process. The percentage of loss will be greater than the metallic oxide content, as some free metal in extremely fine particles always is carried away in grains of slag. From such a comparison, it may be determined whether or not the slag should be melted, sold or treated as before. An example of an actual test of this kind is given below. In a foundry melting 50,000 to 80,000 Ib. of bronze per day, a week's accumulation of furnace slag and ladle skimmings amounted to 16,500 1b.—over three times as much as the foundry superintendent estimated before the accumulation was made. Two tons of this material was taken as representative of the lot. This was ground through a thoroughly cleaned ball-mill and concentrated over a Wilfley table. The

Minerals are vital to any industrialized civilization. Annually, the United States uses more than 4 billion tons of new mineral materials, or about 40,000 pounds per person-about half being mineral fuels and the other half metals and nonmetallics. Stable and economic domestic mining, mineral, metal, and mineral reclamation industries are essential to the economy. The value of United States energy and processed materials of mineral origin exceeds $200 billion annually. Although a number of minerals are imported, especially some designated as "strategic and critical," most U.S. mineral supplies are derived from the domestic mines and processing facilities that you will be seeing, reading about, and visiting as you use this visitor guide. We hope you enjoy your experiences. This pamphlet, a guide to mining and mineral operations that may be observed or visited and some other points of interest relating to minerals, is intended to aid tourists and students who are interested in mining. Some may wish to study our Nation's romantic past; others may plan to enter the minerals industry as a career; still others may have a primary interest in conservation practices. The pamphlet is also intended to aid State and local officials, Chambers of Commerce, and mining firms in answering some of the many questions of tourists and students.

Jan 1, 1977

Three large deposits of good quality lignite were located and delineated in the Central Otago region between October 1978 and July 1979. The program was initiated and funded by Mines Division of the Ministry of Energy as part of the national Coal Resource Survey. The exploration work was carried out by Lime and Marble Limited on a contract basis (Bowman, 1980). The three deposits were all potentially mineable by open cast methods and possessed combined indicated and, inferred reserves in the order of 1000 x 106 tonnes. They ranked with the previously discovered Eastern Southland 1ignites and as such constituted an important national energy resource. Fifteen months later a second more detailed investigation of similar duration was undertaken by the Liquid Fuels Trust Board (LFTB). The objective was to upgrade and refine the geological data base of all of the nine South Island 1ignite deposits in order to make preliminary economic assessments of their potential. Again Lime and Marble Limited acted as the exploration operator (Bowman, 1981a, 1981b, 1981c).

Jan 1, 1983

By John D. Morgan, Sylvain J. Pirson

An instantaneous and continuous analysis of a mineral suspension should be of great value in controlling various mineral preparation processes. Described herein is a method of analysis based on the use of high-frequency alternating current, which, under certain restrictive conditions, could be of use. Theoretical Considerations In a suspension of conductive minerals, the electrical effect primarily responsible for the variations in electric conductivity is the capacitance. In Fig Ia, let an alternating voltage E be applied across two electrodes F and F', between which are two rows (S and T) of mineral particles, all of approximately the same size, immersed in a fluid. Let the number of rows of particles between the electrodes be R and the number of particles in each row be N. If A is the area of a particle, D is the distance separating two particles, and k is a constant depending on the fluid, the capacity, CO, of the particle system will be given by: KRA C°= ND Referring now to Fig Ib, let R, the number of rows, be held constant, but let N, the number of particles in each row (S and T), be increased X-fold. The capacity, C1, of

Jan 1, 1949

By A. R. T. Denues

"INTRODUCTION The orienting phases of the current investigation of cushioned blasting in the Explosives Division of the Bureau of Mines were indicated in a previous publication (5) 3/. Pertinent literature reviewed therein indicated a highly controversial field. This emphasized the need for experimental studies of many factors that affect the health and safety of miners and the efficiency of mining operations. Results of some orienting tests showed marked effects on practical hazards. Further, they emphasized the necessity and importance of the contemplated investigation. The scope and general plan of these practical inquiries into the safety of cushioned blasting were indicated.This investigation of cushioned blasting relates to the various means employed to reduce the intensity of application of energy from explosive actions in boreholes. It has been suggested (from p. 19 of reference 5) that the divisions of this work would correspond to the salient hazards affected by cushioned blasting. These include the ignition hazard, hazards from poisonous gases, and other practical hazards in the blasting technique. The ignition hazard was resolved into two components of approximately equal weight. These include studies of effects upon (1) the incendivity of blown-out shots and upon (2) the occurrence of such shots. Experimental studies of effects on the incendivity of blown-out shots were first undertaken. Questions of the best procedure for making these evaluations have been adduced, and the interpretation and utilization of the results of gallery testing seemed to require detailed attention; some preliminary general considerations of such testing were therefore necessary."

Jan 1, 1943

By W. G. Johnson

"As we move into 1983, Canada is not only in a deep recession, there are major changes taking place.International competition is growing fiercer.Major core industries such as automobile, steel, mining, oil, agriculture, forestry, fishing, major manufacturing and others are just not expanding.If and when recovery comes starting in mid-1983, as many predict, don't expect industries to suddenly resume former growth patterns. It's just not possible.Companies, by necessity, are becoming lean and mean, and they are still in the process of reducing staff to meet changing times and conditions. Many of the staff now being released may never return to fulltime work with a single employer, particularly if they cannot measure up to more exacting performance standards and management expectations.There are clear cut instances of people who lose a job for reasons beyond their control. A merger, the loss of function, or a major reorganization sometimes creates casualties of people who were excellent performers. Such people can survive well, based on the tongue of good report and with some help from associates or others. However, even good performers often have difficulty in adjusting to the rigors of finding a new job and to become their own personal salesman."

Jan 1, 1983

By Jack J. Ayotte, Michael R. Nadon

"Today's demand for better and more efficient methods inspires new approaches to construction and mine development.A project at Asarco's Aquarius Mine provided a challenge that resulted in the adaptation of a civil construction technique to a mining application.This paper describes the construction of an escapeway shaft to surface from the mine's 150m level. The prime consideration was to provide the most cost-effective method of establishing a shaft collar in the 145 ft (44 m) of water-bearing overburden. This problem was resolved with the employment of the drilled in-caisson method.The remainder of the 500ft (152m) deep shaft was raise bored and portable hoisting equipment was used to install a permanentmanway and shaft liner.IntroductionHaving completed the first phase of exploration development in 1982, J.S. Redpath Limited was engaged to carry out an engineering and cost study to investigate the feasibility of re-opening Asarco's Aquarius Mine near Timmins, Ontario. The scheme was to develop the proven ore reserves and proceed with shrinkage stoping while carrying out further exploration development and diamond drilling.One significant and costly component of the project was the provision of an escapeway shaft to supply additional ventilation as well as a second means of egress from the mine. The major complication to this task was the presence of 145 ft (44 m) of water-bearing overburden at the site. The first and obvious approach was to use conventional ground-freezing methods as had been employed previously on .this property for the initial development shaft. This being the only ""sure"" method available at the time of the budget estimate, it was used as a basis for the study but its considerable projected cost and time demand inspired further investigation into other possible solutions.After considerable research and several brainstorming sessions, a Redpath team came up with an approach whose basic procedures had been used extensively in the civil construction field, although they were novel to the mining industry."

Jan 1, 1987

Novel flotation reagents were developed to improve the flotation of coarse particles. Laboratory tests conducted on an anthracite coal sample from Kyung-Dong Coal Company, Korea, showed that the reagents can successfully clean 2?3 mm top-size materials. Pilot-scale tests conducted on a 1.41 mm x0 coal gave substantially better results than those obtained using kerosene as collector. The pilot-scale test results were used to develop a flowsheet, in which the 1.41 mm x0 fraction is cleaned by flotation and the 4 x1.41 mm coal is cleaned by single-stage spirals. The performance of this circuit was compared with another flowsheet, in which the 0.5 mm x0coal is floated using the conventional flotation reagent, with the 4 x0.5 mm material being cleaned using two separate spiral circuits. The performance of the two flowsheets was compared by computer simulation. The results showed that the flowsheet consisting of the coarse particle flotation circuit can give substantially higher yield sat a given product grade. Keywords: coal flotation, coarse particle flotation, collector, spirals, computer simulation.

Jan 1, 2002

By P. T. Slatter

The efficient and accurate design of pipe and pumping plant for non-Newtonian mineral slurries remains a problem. The objective of this paper is to present the development of the Balanced Beam Tube Viscometer (BBTV), an instrument which could facilitate more accurate design for these slurries. The background of rotational and tube viscometry is reviewed and the fundamental principles and inherent advantages of the BBTV are given. The design, data acquisition and processing techniques are introduced and results showing the reliability of the new instrument are presented and discussed. It is concluded that the BBTV is a reliable and versatile instrument for both routine analyses and research work, and has the potential to provide data for the refinement of the design procedure for mineral slurry pipe and plant design.

Jan 1, 1998

The Hyde-Macraes Shear Zone (HMSZ) is low angle, duplex thrust system that has developed in a graphitic pelite schist within the Otago schist belt, New Zealand . At Round Hill lateral ramps have developed parallel to the movement direction between+ the footwall and hangingwall shears. These structures exhibit normal oblique-slip displacement which has been an important mechanism for creating space in an otherwise compressional system. Gold-bearing quartz veins were emplaced along the boundary shears and lateral ramps during thrusting. Gold within the lateral ramps is coarse (up to 300 microns) however hanging wall cataclasite development in the boundary shears after the gold was deposited has reduced the grainzise of most of the gold to less than one micron. This bimodal gold distribution has metallurgical implications with respect to the maximisation of gold recovery at Macraes.

Jan 1, 1993

By J. S. Harington

Our purpose is to record and to explain the widely changing numbers of the huge total of black workers on the gold mines of South Africa over the century from 1896 to 1996. These men were recruited from up to twenty territories, and their contributions are examined. The major areas providing labour over this long period have been Lesotho, the former Transkei within South Africa and Mozambique. From 1989 to 1996, for instance, these three areas accounted for over sixty per cent of the total labour force (tlf). Our principal Figure 1 shows the tlf fluctuating through time to reach a peak of 480 000 in 1988. Irregular falls are also documented with the most serious in 1995 to 180 000. Based on this graph we consider the political, economic, sociological and historical reasons behind these changing employment opportunities. These have included external world-scale events such as war or depression, as well as internal changes of national economy and policy. We show the importance for numbers employed of the discovery of gold in the Orange Free State in 1946, the influence generally of the ?Winds of Change? and the firm maintenance by the State of law and order. Varying gold production costs and profitability against high tax rates, allied with increasing wages and a lack of development capital, have led in the last decade to employment falling by fifty per cent, despite an actually higher value of gold output. Finally, this analysis considers the role of the migrant labour system as it affects, and is affected by, conditions in the gold mining industry, with special reference to its less than humane consequences in the numerically dominant territories of Lesotho and Transkei.

Jan 1, 2004

By N. D. L. Burger

A low noise blast hole drilling system was developed to limit the risk of noise-induced hearing impairment in mining operations. Noise- induced hearing loss has been identified as a major occupational health risk in SA mines. The noise generated by pneumatic percussion drills is a major contributor to such noise-induced hearing loss. This motivated the South African Safety in Mines Research Advisory Committee (SIMRAC) to commission the development of a low noise rock drill system. The system had to be designed, manufactured, tested and demonstrated in a simulated underground mining environment. The specification required noise levels below 90 dBA. Other important design considerations were ease of manual transport, setting up and operation. The primary design concept was to encapsulate a standard SecoS215 pneumatic rock drill in a composite material tube. The tube is pushed onto the rock face by a pneumatic cylinder and is sealed at the rock face by an elastic seal. The drill is pulled towards the rock face by a rope and pulley mechanism fitted inside the tube. This mechanism is powered by a second pneumatic cylinder. The actions of moving and setting the drill require two persons. However, the team can carry out the drilling function itself on several drills simultaneously because of the self-thrusting design. The drill is supported by two camlocks. The exhaust (air containing dust, water, rock debris, oil and grease) is removed from the encapsulating tubes via an exhaust tube to the end of the stope. In this way exhaust noise and air pollutants are disposed of away from personnel. Tests were conducted in a test stope. Noise levels of under 90 dBA were achieved, thereby attaining the primary design specification. This was achieved without materially compromising ease of handling. Penetration rate was somewhat improved compared to that of the standard drill, so that productivity could be maintained. Keywords: Drill, rock drill, quiet, noise, mine, underground.

Jan 1, 2004

By Baki Özüm

Early evaluations of Pasquia Hills kerogen shale deposits by Geological Survey of Canada, Saskatchewan Geological Survey, Manitoba Energy and Mines and Sun Oil Company, using modified Fischer Assay, Rock-Eval and other techniques, estimated recoverable reserves of about 2.6x109 barrels of oil in areas favorable for strip-mining; each metric ton of ore was determined to yield about 30 L to 50 L of shale oil remarkably high in aromatic compounds. Western Petrochemical Corp. (WPC) is holding two Oil Shale Exploration Permits covering about 76,635 hectares in the Pasquia Hills Region of eastern Saskatchewan and conducting a 15-corehole drilling program to determine stratigraphic correlation on both first and second white specks kerogen shale. In this program, correlation will be established between oil yield and oil quality, using different retort techniques, including modified Fischer Assay, steam retort and Rock-Eval. Results will lead to further resource evaluation and to a preliminary engineering design for a shale processing plant, including selection of retort process, upgrading of shale oil to petrochemical feedstock, hydrogen management, energy balance and evaluation of environmental impact.

May 1, 2002