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Coal Preparation Research at Turkish Coal Enterprises (TKI)

Sep 13, 2010

James Barnes is Managing Director of James Barnes & Associated Ltd which is a company that has invested ten years of development to provide developers with a transparent, user friendly consultation framework that identifies who needs to be consulted, how they are to be consulted and procedures required to manage the risks associated with getting all the wrong! Despite the assertion above, this paper is not about to provide delegates with the answer to whom they ought to consult or identify the expectations that Maori might have in regard to the consultation process. It would be a very brave person indeed who would venture an opinion on such a sensitive subject. There are no short cuts to finding out what expectations Maori might have on any given situation. Nothing can be taken for granted. What this paper will attempt to do however is provide practical insights into what might be on the minds of Maori interests as they deal with the issues associated with mineral resources, particularly those under Treaty of Waitangi Claim. The Treaty of Waitangi has a significant bearing on the current debate between Maori and the Crown regarding ownership of mineral resources in New Zealand. The Waitangi Tribunal is currently hearing a case presented by a number of Iwi over the ownership of oil and gas resources in Taranaki and Hawkes Bay. Others will follow. The Crown and Maori have never been able to settle differences over ownership rights without resorting to legal action and it looks like this scenario is about to be repeated in regards to minerals. The Crown has a duty to actively protect the Maori interest. This is a fundamental expectation in the relationship between Maori and the Crown. In the case of minerals, Maori have yet to see the Crown do its duty. The impact on developers has become evident through Maori objections to consent applications as the issues of mineral right remain unresolved.

Jan 1, 2000

By W. M. Dressel

This Bureau of Mines report describes a shaft closure demonstration project in which 11 inverted pyramid-shaped plugs were used to plug abandoned open mine shafts in Galena, KS, The inverted pyramid-shaped forms, fabricated from steelplate, were designed so that the inverted base would be larger, by 4 ft on a side, than the approximate size of the shaft opening at the surface residuum-solid rock interface. After the surface openings of the shafts were trimmed with a backhoe, the steel forms, complete with reinforcing, were lowered into the openings and filled with concrete; the remaining portions of the openings above the plugs were backfilled to slightly above the surrounding surface level with waste rock and soil. Location and elevation monuments were installed for long-tern evaluation of the success of the project.

Jan 1, 1985

By W. J. Boone

The Bureau of Mines has programmed for publication a series of Reports of Investigations of studies it has undertaken on low-temperature phase equilibria of several helium-bearing natural gases. This report is the second of a series of papers of the same general title; it is anticipated that additional reports of this series will be published. The advent of a helium conservation program and the prospect of production of helium by private industry, make it especially desirable to publish these data. This report describes phase equilibria related to a natural gas that is processed for helium at the Bureau's Exell Helium Plant (located about 35 miles north of Amarillo, Tex.). Carbon dioxide and water in the gas were removed before making the study; hence the data obtained are representative of the gas stream immediately after similar preliminary treatment in the plant process. Phase equilibrium data were obtained for conditions from -50° to -275° F. and from 100 to 500 p.s.i.a. Analyses of samples were made as follows: For a given run at a selected temperature and pressure, samples of the vapor and liquid phases were analyzed by mass spectrometer, and an additional sample of the liquid phase was analyzed for helium by means of special apparatus (7). 4

Jan 1, 1962

Westwood Quebec Long Life, Low Cost CONSTRUCTION UPDATE ? Shaft advanced to 840m (after 1 year), 3 km of down ramp and 2 km of exploration drift ? Head frame and hoist room structure completed ? 2009, 84,700m drilling program completed (increase 9%) 2010 OUTLOOK ? $102 million expenditures planned ? Shaft to advance to 1,300m and the first loading excavate 71,500m drilling program planned

May 1, 2010

By M. F. Goudge

Introduction It is only fitting on this occasion of the fiftieth anniversary of the incorporation of the Institute that we should indulge in a bit of retrospection and review the progress that has been made within this period in the various branches of the mining industry- progress that is so closely associated with the members of this Institute. Such a moment of retrospection will enable us better to appreciate the present status of the industry and to perceive more clearly the trends that should guide us in making sound plans for the future. The past half century has been a period of amazing industrial progress in Canada. In this period, the economy of our country has changed from one based chiefly on agriculture and the export of raw materials, to an economy based largely on a well integrated manufacturing industry. In all' o( these major developments, industrial minerals have played an important part and will play an increasingly, important part in the future. By ?industrial minerals? we mean the various non-metallic minerals (exclusive of fuels) as well as the rocks, sands, and clays used for industrial purposes. They are now used so widely and in such large quantities that modern industry could not function without them, and their continued availability at low cost is vital to the industrial future of Canada. The key position occupied by industrial minerals in modern Canadian industry was well illustrated two years ago when a strike occurred in the only Canadian plant producing soda-ash and calcium chloride at a time when those materials were already in short supply and unavailable from other sources. Within a short time of the shutdown of this plant, in which the two principal raw materials are limestone and salt, the great aluminium reduction plants on the Saguenay river were forced to curtail operations because of the lack of soda-ash, essential to the process of extracting aluminium from its ore. Automobile production, already harassed by a shortage of steel, was further hampered when glass for windshields and windows could not be supplied because the glass industry was slowed down almost to a standstill for want of soda-ash. Soap became almost unobtainable both to the housewife and to industrial users, because soda-ash is required in its manufacture. As a consequence of the soap shortage, the production o synthetic rubber at Sarnia was threatened because soap in large quantities is essential to the polymerization process. Motorists on gravelled highways all over Eastern Canada drove through clouds of dust because calcium chloride, used for dust laying, was not to be had. There were other cases of dislocation of industry related to the shutdown of this particular plant, but the above illustrates the wide ramifications of industrial minerals in modern industry. However, it is extremely doubtful if many Canadian citizens realized that these apparently unrelated happenings were connected in any way with limestone and salt.

Jan 1, 1948

By James L. Weeks

Introduction This paper attempts to summarize some of the major criticisms of drug testing. Eight problems with drug testing are discussed. These are: • It does not measure something employers have a reasonable need to know, • It is a distortion of priorities, • Drug use is not known to be associated with increased risk of occupational injuries, • Drug testing is proposed as a dangerously simplistic solution to poorly conceived problems, • In the absence of safeguards, it is unacceptably inaccurate, • In the absence of treatment commitments and confidentiality protection for persons dependent on drugs, it is an unethical practice of medicine, • Drug testing is an invasion of privacy, and • It will have a negative effect on treatment of persons with drug or alcohol dependencies. Employers' need to know It does not measure something employers have a reasonable need to know. It is reasonable for employers and fellow workers to want to know if workers are functionally impaired (intoxicated) while on the job. Drug testing does not measure impairment. It measures the concentration of drug metabolities in urine or blood. Unlike measurements of blood alcohol concentration (BAC), drug metabolites are not correlated with impairment or intoxication. They indicate only drug use in the one to two weeks before a urine sample. And, in some instances, they indicate chronic use. Impairment caused by drug use, on the other hand, occurs immediately and declines rapidly within hours. Drug metabolites may linger for days afterwards. Drug metabolite concentrations in urine are a function of (Morgan, 1984; Schartz and Hawks, 1985; MMWR, 1983): • the amount and purity of drug consumed before taking the test, • when the drug was consumed, • whether the person was a chronic user, in which case a certain amount of drug metabolites would be stored in body fat and slowly released, • the person's metabolic rate, and • for metabolites in urine, any dilution effects of urine. Only the first two factors has

Jan 11, 1987

By James Pile

Long, high capacity, highly tensioned, cable bolts (strand bolts), stiff enough to be installed with resin like a solid bolt, yet flexible enough to be used in any lengths, have been widely used in Australian coal mines since the early 1990?s. A brief history and update on recent developments of this technology is provided. The first major US trial of this Australian technology, has recently taken place at BHP Billiton?s San Juan longwall coal mine in New Mexico. Thirty-five foot long, high capacity, highly tensioned, post-grouted cable bolts are being used to provide active secondary support of intersections in areas where operator safety and life of mine considerations are paramount, and standing support cannot be installed for reasons of equipment access. The cable bolts are resin anchored into overlying sandstone channels, tensioned, and post-grouted. The installation procedure and support results for these highly tensioned cable bolts are given.

Jan 1, 2007

By Charles Kingsley

THE PRESIDENT (DR. C. B. KINGSTON, member C.l.M.M.) expressed regret that neither of the authors of the paper was able to be present to submit the paper in person. In their absence, it would be introduced formally from the Chair. It was a clear, straightforward account of a fine piece of shaft sinking, cleverly conceived and boldly executed. He referred briefly to the distribution and nature of the Dome ore-bodies and stated that, for both the miner and the metallurgist, the mine had provided a wide range of problems of unusual interest. Discussion on the paper was then invited. MR. THOMAS PRYOR said the paper was most opportune, because the subject of internal shafts did not appear to be fully treated in current mining literature. Many members were not familiar with Canadian gold deposits and it would be of interest if the authors could give a brief description of the location of the ere deposits of the Dome mine. This information would doubtless explain why a new internal shaft was needed in a position which required such an exceptionally long cross-cut to connect it to the main hoisting shaft to surface. It would also add to the value of the paper if the authors would give some idea of the duty expected of the new shaft in terms of tons of rock hoisted and of trips engaged in the transport of men and materials, and it would be helpful if figures could be given of the total capital cost of the hoists and subsidiary excavations at the shaft top, and of the cost per foot for sinking and lining the shaft below the collar. Turning to details of the paper, one was favourably impressed by the care given to the provision of a good travelling way for men in the main cross-cut, as shown in Figure 1. It was by no means always that one could walk in comfort and safety in a working where there was a 20-in. ventilating pipe in the roof.

Jan 1, 1939

By Baha Abulnaga

Slurry pipelines are used in a number of countries to convey processed ore mixed with water over long distances from remote mine sites to ports or plants for further processing. In Egypt and Sudan, numerous mineral resources are scattered in remote areas. Through the years, Egyptian geologists have identified 268 sites for metallic ores and 386 sites for industrial nonmetallic minerals. A large portion of these sites are in the Eastern Desert in an area called the Nubian Shield. Similar sites are found in the Sudan where mining contributes to less than 1 percent of the gross domestic product (GDP). There are three important components of infrastructure needed to develop these resources ? power, water and transportation. While Egypt is able to satisfy 70 percent of its needs in iron ore from the Gadideh Mine in the Western Desert, it needs to expand its other resources to reduce imports heavily sedimented. Dredging of these sediments and transporting them by slurry pipelines would enhance an industry of bricks or agricultural development based on tailings technology often used in mining. This article explores the potential for slurry technology for opening new mines in the desert or recuperating the sediments of the Nile. The technology by itself would be new to both countries and would benefit from collaboration, particularly to de-silt the Nasser-Nubia Lake.

Jan 3, 2010

By Michael Mann, Kenneth K. Eltschlager

The International Society of Explosives Engineers (ISEE) Standards Committee has recently updated both the Field Practice Guidelines for Blasting Seismographs and the Performance Specifications for Blasting Seismographs. The revisions are the result of public and industry input along with recommendations of the ISEE Blast Vibration and Seismograph Section. The committee is comprised of blasting seismograph manufacturers, users and general interest personnel. On an as needed basis, subject matter experts are enlisted to advise the committee. Three phases of activities are necessary for each revision cycle: request for comment on the existing standard, first draft revision of the standard based on public input, and final draft approval by the ISEE Board of Directors. The ISEE standards revision process will be explained and each standard will be discussed along with the significant revisions from the latest revision cycle.

Jan 1, 2018

Geophysical Abstracts 1 - 86 were issued in mimeographed form by the Bureau of Mines; Abstracts 87 - 111 were published in bulletins of the Geological Survey; Abstracts 112 - 120 were issued in mimeographed form by the Bureau of Mines as Information Circulars 7256, 7257; 7267,`7273; 7285, 7292, 7303, 7310, and 7324. 1. GRAVITATIONAL METHODS 7933. Ansel, E. A Eine Untersuchung zum Problem der Isostasie (An Investigation Regarding the Problem of Isostasy). Gerlands Beitr. Geophys., Leipzig, vol. 59, 1942, pp. 16-26.

Jan 1, 1945

By J. A. Cox

The Ashanti mine is located within the Lower Proterozoic Birimian of Ghana, and covers a concession of 474 square kilometres at its Obuasi operations which comprise large scale underground, surface and tailings treatment facilities. The mine had operated for a century at the end of 1997 and had produced nearly 25 million ounces of gold, a significant proportion of which came from the underground operations. This paper covers the strategy under which exploration for both surface and underground mineral resources was instrumental in enabling the expansion programme to go ahead together with the methodologies and results that have developed in the exploration area over the last five years. Within capital expenditure constraints, the objective on surface is to replace oxide depletion with a secondary objective of discovering new sulphides in areas other than the main trend. In the underground, the exploration strategy is directed at replacement of both underground and surface sulphide depletion, minimising finding costs and assisting the development of long lead time infrastructure. The exploration application describes the methodologies in use for both surface and underground exploration that have been developed in recent years in conjunction with a description of a major review conducted in 1995/96 of the exploration database using an integrated approach, geochemistry, geophysics, remote sensing and structural geology. A revisit of soil geochemical data in particular, and modification of exploration methodology led to the success in finding relatively significant new oxides in 1997.

Jan 1, 1999

By H. J. Heinen

This Bureau of Mines report reviews the recent developments in the heap leaching of gold ores with dilute cyanide solutions and the recovery of gold and associated silver from the pregnant effluents by a carbon adsorption-desorption method. Mineralogical considerations, experimental work, field studies, and commercial operations are described. Also presented are recent process advances developed by the Bureau, including the application of (1) alcohol additives to the conventional hot alkaline cyanide strip solution to enhance gold desorption from precious metal-laden activated carbon, and (2) Na2S precipitation of the silver from geld-silver cyanide solutions as a means of reducing the inventory of carbon required for precious-metal adsorption from heap leach effluents and for the production of low-silver bullion from activated carbon stripping solutions.

Jan 1, 1978

By Y. Zhoa

The surface morphology of materials is of fundamental importance to many surface related applications, such as wetting, friction, reflection, drag, and adhesion. Various approaches for micro/nano patterning atop polymer surfaces have been proposed in recent years. However, a cost effective technique is still highly in demand. In this paper, we demonstrate a novel but rather simple and generic approach for surface micro/nano patterning using shape memory polymers (SMPs). Different types of novel patterns are realized and their 3-D surface features are quantitatively analyzed by a PLµ Confocal imaging profiler.

Jan 1, 2010

By L. A. Roe

Magnetic separation of iron ores is one of the fastest-growing segments of the minerals beneficiation industry. The tonnage of taconite ores processed annually by magnetic separation will, in a few years, reach 100 million. Magnetic separation occupies an attractive position in the field of ore beneficiation. It is a simple yet effective method, used for some 150 years and steadily growing more important. This type of beneficiation orginated in 1792, when William Ful-larton was issued a British patent covering the separation of iron ore by magnetic attraction. What is magnetism, and why are some materials capable of being magnetized and others not The study involves many unknowns, and even a partial answer to these questions would be a dissertation in solid state physics and perhaps other fields of science. But the last two decades have revealed basic facts as to why certain materials are magnetic and what happens to them when they are magnetized. Some of the newer studies in solid state physics have developed a theory that can be applied to studies of magnetism. It is claimed that magnetism stems fundamentally from the spin of electrons in atoms that tend to go in pairs, spinning in opposite directions. The atom as a whole can act as a magnet only when there is an imbalance of electronic spin. Whenever an atom has an odd number of electrons, therefore, this imbalance exists. This neutralizing effect explains why a piece of material that contains atomic magnets is not necessarily magnetic. The physicists tell us that iron is composed of many small magnetized regions called domains, which consist individually of millions of atoms. The piece of iron becomes magnetized when an external force lines up these domains in the same direction. Fundamental data developed by physicists working in fields far removed from minerals beneficiation are now available for developing better magnetic separators for ore processing. More Data Needed on Magnetic Properties of Minerals: There is less information on magnetic properties of minerals than there is for certain aspects of magnetic separator design. When the data on magnetic properties is available, it is often directed toward the study of powders for tape recorders and other highly scientific endeavors that are of little use to the beneficiation engineer. W. R. Crane's table of tractive forces, published in 1902, is still a guide in the study of magnetic minerals. Bits of other information regarding electrostatic conductivity, dielectric constant values, and permeability of various minerals have also appeared but are of small practical value in magnetic separation of ore. It is extremely important to obtain pure mineral specimens for making investigations and to record results that may be of use in studies of magnetic processes. Reference to the large volume of data developed by those concerned with analysis and design of permanent magnets soon reveals that these people have extensively evaluated the effect of various impurities on magnetic properties. Much of the science of the ferrite industry is based upon spinel-type structures which are varied by substitution of selected elements or even subtraction of elements, leaving vacant sites in the space lattice. Magnetic separators are used to beneficiate a wide variety of industrial minerals. In this application the relatively large volumes of nonmagnetics are usually the commercial products. The amount of mag-

Jan 1, 1959

By Débora Cardoso de Oliveira Silveira, Jean-Christophe Huber, Hamzeh Hamadeh, Kateryna Pastel, Guillaume Brosse

The dynamic behavior of oxygen gas flow, determined by the lance nozzle and blow pattern, is a key factor for determining jet efficiency in BOF Steelmaking. The present work compares the performances of Laval and parabolic nozzles with the aid of the Computational Fluid Dynamics (CFD). The Method of Characteristics (MOC) was applied to design a minimum length parabolic nozzle. The results show that the parabolic nozzle generates more uniform and stable jet, with 2% longer potential core and supersonic length and less shock waves. For the parabolic nozzle, the pressure nearby the nozzle wall is higher, which can protect this region from reverse flow of converter gases and offer longer life for the lance tip. Likewise, the flow rate variations would affect less this nozzle. In addition, the nozzle wear was investigated, and the parabolic nozzle has proven relatively less sensitivity to the presence of this deformity.

Oct 1, 2019

By Mohamad Hussein

Low strain dynamic tests are performed to evaluate the structural integrity of driven or cast-in-place concrete piles. This type of testing requires minimal pile preparation, and is simply performed by attaching an accelerometer to the pile head and striking the pile head with a hand held hammer. The measured data is processed by a dedicated system, inspected for wave reflections, and interpreted based on one dimensional wave propagation theory. Piles are normally tested shortly after installation so that problems can be identified early and corrective measures taken before construction of the superstructure. However, evaluation of existing foundations is occasionally required. Often, pile installation records are not available rendering impossible any rational foundation reanalysis. This paper discusses three case histories where low strain dynamic measurements allowed determination of pile lengths and structural integrity under existing structures where pile heads were not accessible.

Jan 1, 1992

By P. P. Jenkins, T. G. Ball

Paper presented at the Drillex '90 conference held in London, 5 April 1990. Two drilling techniques are employed - guided longhole drilling and reverse circulation coring - for underground longhole exploration of the coal reserves and the fault structures that affect them. These are complementary to, or replacements for, surface boreholes, underground development drivages and seismic techniques. The developments of the drilling techniques and some case histories are presented in detail.

Jan 1, 1991

By Sivilay Sayavong, David Puller, Julian Gatward, David Hard, Martin Stanley

"AbstractThe Thames Water Tideway Tunnels programme involves the upgrade of London’s combined sewer and storm water system. The first section is the Lee Tunnel between the Beckton Sewage Treatment Works (STW) and the Abbey Mills Pumping Station. This will intercept the overflows currently discharging to the River Lee and has the capacity to store and transfer 350,000m3 of storm water and sewage. The project required 4 shafts and a 6.9km 7.2m diameter tunnel. The shafts are some of the largest ever constructed in the UK, with diaphragm walls up to 98m deep and 1800mm thick. As a result of the innovative methods of diaphragm wall design and construction adopted the 4 very large and deep shafts were able to be excavated and completed safely, with minimal water ingress and with extremely high quality.MVB, a joint venture of Morgan Sindall, Vinci Construction Grands Projets and Bachy Soletanche are delivering the £635m contract with Thames Water’s Project Management Team in a collaborative manner under an NEC contract. Mott MacDonald, Morgan Sindall UnPS & Bachy Soletanche are acting as designers.Some of the important advances in diaphragm walling made included:??Diaphragm wall design to both EC2 & EC7 taking into considering the assessment of chalk stiffness, high hoop stresses, large multiple openings and non-axisymmetric loadings.??Formation of shafts as a faceted circle from a series of overlapping panels, with primary panels up to 7.2m wide demanding concrete volumes up to 1300m3 be poured in one go. Overlapping secondary single bite panels cut into the grade C50/60 concrete.??Excavation of the full geological stratigraphy of London making bentonite management complex.??Panel verticality of 1:300 required over the full depth. The results achieved this and in many cases exceeded expectations with some panels coming in at up to 1 in 800 with the majority at 1 in 400 to 1 in 500. The project is also the first in the Soletanche Bachy Group to take data from the ultrasonic drilling monitor used to check the verticalty in electronic format in order to create 3D CAD as-built drawings.??Each diaphragm wall panel was reinforced over its full depth. Up to 18 separate pieces of reinforcing cage had to be installed in primary panels. Cages underwent a full range of temporary works designs to check that lifting, splicing and placing could all be undertaken safely. Fibreglass was used in the tunnel portals in the shafts to ease breakthroughs."

Jan 1, 2014