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Coal Preparation Research at Turkish Coal Enterprises (TKI)

Sep 13, 2010

Provide the mining industry with a simple, accurate and readily available means of measuring the gas flow from pipe outlets such as gob holes Approach The Bureau of Mines conducted laboratory studies to establish correction or method factors for anemometers when used to measure gas flow from pipe outlets. Using the Anemometer Anemometers are used by the mining industry to make air velocity measurements in mine entries. Although the instrument has no appreciable influence on the airstream in mine entries, especially since the cross-sectional area of an entry is much larger than the cross-section of the anemometer, correction or method factors are used to correct the center line anemometer velocity to average velocity. This adjustment is made because the air velocity in a mine entry is highest in the center and lower at the sides. Anemometers can be used to measure gas flow from small diameter pipe outlets; however, since the instrument diameter is much larger than one-sixth of the pipe diameter, it will influence the air-stream from these small outlets. Resulting velocity measurements are erroneously high by as much as 30 percent. Method factors must be applied to such anemometer measurements taken at pipe outlets. Through a research investigation the Bureau of Mines established a set of method factors for center-line anemometer readings taken at the discharge end of 4-to 8-inch diameter pipes. These method factors were combined with method factors which were developed by the National Coal Board of Great Britain for 12-to 30-inch diameter pipes. The anemometer was mounted on the end of a short rod and held against the pipe for support except on the 4-inch pipe where the instrument was started and stopped remotely to prevent hand interference with the air-stream during measurements. Method factors were determined by comparing the anemometer measurements at the pipe outlet to the true average airflow which was simultaneously determined upstream by venturi measurements. Consequently, a method factor is nothing more than the ratio of the true velocity to an anemometer measurement.

Jan 1, 1987

By M. Iberico

A partir de los años 70 se incrementó el proceso de exploración y desarrollo de los yacimientos mineros submarinos. En este sentido, el presente trabajo describe el origen de los depósitos a partir de los descubrimientos de módulos manganíferos en el océano pacífico que hicieron Thompson y Murray. Posteriormente Buchanam demuestra la existencia de módulos ferro-manganíferos en aguas poco profundas ( 200 m. ), de composición diferente de las provenientes de aguas profundas. De otro lado, el trabajo señala también la división de los minerales marinos en tres categorías: las sales disueltas y en organismos, los sedimentos y depósitos en el suelo profundo submarino y los depósitos consolidados e inconsolidados de la plataforma continental. Por último, se describe los procesos de beneficio y las ventajas de la explotación de los recursos submarinos en el futuro de la minería submarina.

Nov 20, 1972

By S Kundu, J Zanganeh, D Eschebach, B Moghtaderi

The concentrations of methane and coal dust vary from one location to another in underground coalmines. In the presence of an ignition source, such as static electricity, these mixtures can initiate explosions and consequently cause massive destruction. Research data can help in understanding the level of hazards and associated risk these flammable mixtures can produce. For instance, the level of peak explosion pressure and flame speed can be well understood from experimental and numerical research data. With this aim, methane–air mixtures and methane-coal dust-air mixtures were employed in a ducted spherical vessel. According to literature, the maximum value of peak explosion pressure can be obtained in vessels of spherical geometry when compared to vessels of other geometries. Thus the values of explosion parameters generated from spherical vessels can be incorporated in understanding the highest level of hazard that can occur in a real world scenario.In this study, the duct integrated with the vessel resembles any channel or pathway connected to a methane and/or coal dust rich area in the mine. Experimental investigations emphasise that the severity of explosion in the explosion zone transmits to the channel or pathway. The length of the channel or pathway also plays an important role on the values of explosion parameters. The greater the length of the channel or pathway, the higher the explosion pressure is and therefore the higher the destruction. Ignition energy and concentrations of methane and coal dust were varied in collecting experimental data. The data of explosion parameters thus obtained can be employed in addressing hazard mitigation strategies in coalmines.CITATION:Kundu, S, Zanganeh, J, Eschebach, D and Moghtaderi, B, 2017. Incorporating research data in addressing methane and coal dust fire, and explosion hazards in coalmines, in Proceedings Australian Mine Vent Conference 2017, pp 175–180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By K. M. Kim

A site-specific blasting model has been developed for the Asarco Mission mine. The main inputs to the model are the in-situ block size (F80), the post-blast fragmentation (P80) and the intact tensile strength (To). The output from the model is the specific blast energy (ESE). Modern techniques are being used to obtain the input parameters for the site-specific blast fragmentation model. In particular, image processing software is used to obtain both the in-situ block size and the post-blast fragmentation, and the Schmidt hammer is used to obtain the tensile strength at numerous locations throughout the rock mass. An initial model was developed using five test shots in one area of the mine that contains Argillite and is relatively homogeneous. This also included calibrating Schmidt hammer readings against actual Brazilian tensile measurements. The model for Argillite will be updated as more tests are conducted, and the model will be extended to the other four primary rock types at the Asarco Mission mine.

Jan 1, 2011

Using DEM to Model Industrial Banana Screens

Sep 13, 2010

By I. P. Barbosa, P. S. M. Soares, I. O. C. Masson

"Permanent magnets have been applied extensively to several electronic products such as printers, TV sets, microphones, microcomputers and headphones, presently manufactured in large scale by industrial economies. Sm-Co alloys represent about 20% of the world market for permanent magnets and their industrial processors generate 20-30% of magnetic scraps which can be recycled. This paper discusses a process route to recycle SmCo5 using acid treatment, solvent extraction of Sm and electrowinning of Co. The results confirm the feasibility of the alternative proposed. Basic operational variables are suggested as guidelines to design a plant for recycling magnetic scraps.The use of hydrometallurgical processes to recycle scraps from the industry of permanent magnets has been suggested in some recent papers related to recycling of metallic alloys [ 1 ]. These research efforts might be understood as a worldwide tendency towards the development of self sustainable metallurgical processes which mean the reduction of environmental impacts.CETEM -Center for Mineral Technology leads in Brazil several research programs concerning recycling and treatment of industrial residues. The work on samarium purification and concentration by solvent extraction, producing also a solution of cobalt sulfate as partially reported here is one of these programs. Previous results related to the sulfuric acid digestion of SmCo5 are presented somewhere else [2]"

Jan 1, 1997

By Shazad Hosein, William Birch, Douglas A. Anderson

This paper will present the results of tests of a new method for assessing explosive performance using wavelet transform analysis of standard blast seismograms. The theoretical background of the method was presented at an earlier ISEE conference.

Jan 1, 2015

By CHARLES L. WRIGHT

Previous work.-The general plan of work outlined for the Government fuel-testing plant erected at the Louisiana Purchase Exposition, at St. Louis, Mo., in 1904, included investigations relative to the briquetting of coals found in the United States. These investigations embraced the possibility of making satisfactory commercial fuels from lignite or low-grade coals which do not stand shipment well; of benefiting culm or slack coals that are wasted or sold at unremunerative prices; and of improving the furnace efficiency or ability to withstand transportation of good coals. This work was begun in 1904 and was continued in 1905, 1906, and 1907 as an essential part of investigations looking to the determination of methods for reducing waste and increasing efficiency in the utilization of the fuel resources in the United States. The initial briquetting tests at St. Louis, which included examination into the behavior of different coals or mixtures of coals in the briquetting press, experimental study of the merits of various substances used as binders, and consideration of the physical properties and resistance to weather and abrasion of the briquets, have been described.a They demonstrated that satisfactory briquets could be made from most coals, and that by briquetting the commercial value of many low-grade coals and lignites could be raised enough to more than cover the cost of manufacture. Norfolk plant.-The briquetting plant of the Geological Survey was moved from St. Louis, Mo., to Norfolk, Va., in 1907, along with the steam boiler and producer-gas equipment of the fuel-testing plant, as the closing out of the affairs of the Louisiana Purchase Exposition and the consequent removal of the buildings from Forest Park made a change of location necessary. Norfolk was selected largely with a view to the testing of coals for naval purposes, and because of facilities in the way of buildings and materials offered by the Jamestown Exposition Company. The work at Norfolk was chiefly devoted to making steaming and briquet tests of coals which reach the Atlantic seaboard at Norfolk and Newport News and are used by the navy and merchant marine. Two briquet machines were installed at the Norfolk plant, one being the English machine used in briquetting tests by the Geological Survey at St. Louis in 1905 and 1906, and the other an American machine. The briquets made at this plant were tested on locomotives of several railroads entering Norfolk and on the United States torpedo boat Buldle in comparison with the run-of-mine coal used in making them. Some of the tests were conducted by the railroads on their own locomotives, but those on the Biddle and on the locomotive of the Seaboard Air Line Railway were carried on by W. T. Ray and Henry Kreisinger, of the United States Geological Survey. Personnel.-Charles T. Malcolmson continued in general charge of the briquetting section after the removal to Norfolk until January 1, 1908. Walter J. Chapman continued in charge of operation of the briquet machines and of the observations reported under the heading "Details of manufacture." Charles L. Wright supervised the installation of the English briquet machine and later in the year continued the physical tests of briquets and the analyses in the chemical laboratory of the section until January 1, 1908, on which date he was placed in general charge of the work of the section. G. E. Ryder and Ralph Galt also continued with the staff, but the former was obliged to resign soon after the plant was in operation on account of ill health; the latter continued with the section as computer until the close of work on December 1, 1908.

Jan 1, 1911

By Mikko Ruonala, Pertti Lamberg, Olli Hyvärinen

The smelting of copper sulphide concentrate is the dominant route in copper production (Figure 1). Heap leaching of oxidized copper ores with weak sulphuric acid together with copper solvent extraction and electrowinning has gained popularity during recent decades, and it accounts for close to 20 % of primary copper production. Heap leaching offers advantages such as lower costs and consequently the construction of a production plant at a mine site is made possible. Limited resources of oxidized copper ores, the long leaching time of chalcopyrite and inability to recover gold inhibit this growth. The HydroCopperTM process developed by Outokumpu Technology at the laboratories of Outokumpu Research, Pori, Finland, is a new chloride leaching technology /1,2/, which offers an alternative to smelting and heap leaching (Figure 1). In the HydroCopperTM process sulphidic concentrates with various mineralogy and grade can be treated at the mine site to produce high-quality copper. Instead of copper cathodes the HydroCopperTM end products are copper wire rod, copper bars or copper billets. One of the advantages of HydroCopperTM technology is that gold can also be recovered in the process simultaneously /3/. To confirm the functioning of the new process and to dimension equipment Outokumpu Technology built the HydroCopperTM demonstration plant in Pori, Finland /4/. It has a capacity of 1 metric ton of copper per day. After testing with Pyhäsalmi copper concentrate in 2003, the first commercial demonstration run with Erdenet copper concentrate took place in 2004.

Jan 1, 2005

By Robert Vinson

This article examines the spatial variability of dust concentrations within a coal miner?s breathing zone and the impact of sampling location at the cap lamp, nose, and lapel. Tests were conducted in the National Institute for Safety and Health Pittsburgh Research Laboratory full-scale, continuous miner gallery using three prototype personal dust monitors (PDM). The dust masses detected by the PDMs were used to calculate the percentage difference of dust mass between the cap lamp and the nose and between the lapel and the nose. The calculated percentage differences of the masses ranged from plus 12% to minus 25%. Breathing zone tests were also conducted in four underground coal mines using the torso of a mannequin to simulate a miner. Coal mine dust was sampled with multi-cyclone sampling cans mounted directly in front of the mannequin near the cap lamp, nose, and lapel. These four coal mine tests found that the spatial variability of dust levels and imprecision of the current personal sampler is a greater influence than the sampler location within the breathing zone. However, a one-sample t-test of this data did find that the overall mean value of the cap lamp/nose ratio was not significantly different than 1 (p-value = 0.21). However, when applied to the overall mean value of the lapel/nose ratio there was a significant difference from 1 (p-value < .0001). This finding is important because the lapel has always been the sampling location for coal mine dust samples. But these results suggest that the cap location is slightly more indicative of what is breathed through the nose area.

Jan 1, 2007

By Q. Zhang, J. A. Finch

"Sphalerite flotation in the absence of copper activation at moderately alkaline pH has been observed in laboratory studies. An in-plant test of this observation was conducted at Kidd Creek Mine LTD. using a portable minicell flotation circuit. The results confirm that raising the pH causes sphalerite flotation.The testwork with the minicell circuit is described. The circuit, built around 2, 51 cells donated by the Noranda Technology Centre, was funded by Air Liquide and NSERC. It includes a data acquisition system to monitor continuously dissolved oxygen, pH and Pulp potential.INTRODUCTIONFlotation of sphalerite is normally practised by adding CuSO4 as an activator under alkaline pH. Recently there have been a number of laboratory and plant examples of sphalerite flotation without deliberate addition of cu++ ions (Girczys, 1972; Mukherjee, 1976; McTavish, 1980; Marouf et al., 1986; Mielczarski, 1986; Leroux et al., 1987; Palsson and Forssberg, 1989; Sandoval-Caballero et al., 1990; Zhang et al., 1991).In batch tests, with a sample of Pb/Zn ore from Polaris, Leroux et al. (1987) found that sphalerite became floatable after adjusting pH to 9. 5-11: they ruled out natural floatability or the formation of elemental sulphur on the surface but suspected iron hydroxy compounds were responsible. Sandoval-Caballero (1990) conducted a continuous minicell test at Brunswick Mining and obtained a 44 % Zn recovery and 40.5 % Zn grade concentrate without deliberately adding CuS04 at pH= 10.5. With single mineral studies, Zhang et al. (1991) revealed good sphalerite floatability (over 80% recovery) in pH range 8 to 11 and found that this floatability was related to pH, dissolved oxygen (DO) level and Fe++ species present in the system.To explore further the conditions under which sphalerite can float without addition of CuSO4 , a continuous pilot test using minicells was performed at Falconbridge Ltd., Kidd Creek division. The set-up is briefly described (a more detailed description is given elsewhere in these proceedings) with emphasis on the data acquisition system - dissolved oxygen, pulp potential and pH were monitored continuously. Results of testwork investigating pH, CuS04 addition and gas composition are presented."

Jan 1, 1992

By Sunil Koppalkar, Guillaume Noel, Ahmed Bouajila, Makni Sami, Claude Gagnon

"Gold gravity recovery circuits utilizing enhanced gravity separators have become an integral part of many of the modern gold processing plants. Thus, efforts to improve the operating efficiency have been a topic of interest for metallurgists for many years. As part of this endeavour, a methodology to estimate the portion of gold in the ore that could be recovered by gravity separation (gravity recoverable gold or GRG) was developed at McGill University. It has been reported in the literature that the gold content estimated with this methodology is the theoretical maximum that is available for gravity recovery that could only be approached but never achieved. A comparison of GRG recovery obtained in the laboratory with the actual recovery in the plant shows that plants recover between one-third to two-thirds of the value predicted by the laboratory test.Research conducted at COREM shows that particle shape transformation during grinding is a major cause of the discrepancy (even though the bleed percent processed, the quality of cyclone classification and the operating conditions of the gravity separator also contribute to the difference). To analyze the gold particle shapes and their deportment, samples were collected from different streams of a grinding-gravity circuit in a gold plant and compared to a concentrate sample from the standard GRG test. A particle characterization methodology based on gold morphology was developed. GRG mapping in a conventional grinding-gravity circuit and the transformation of GRG into non-GRG, as mainly explained by gold particle reshaping, will be discussed. The knowledge gained from the shape analysis will be used to develop shape distributions and partition curves for the classification of shapes.INTRODUCTIONGravity concentration using centrifugal concentrators has gained increasing popularity since the invention of the enhanced gravity concentrators in the nineteen eighties. Among these, the semicontinuous centrifugal gravity concentrators are most commonly used for recovering gold and platinum group minerals (PGM) from grinding circuit streams. The benefits of gold gravity recovery are now well understood and the acceptance by the mining industry is overwhelming. The occurrence of reasonable amounts of gravity recoverable gold (GRG) in an ore prompts gold mills to install gravity circuits. Thus, the increased use of gravity concentration has necessitated a better understanding of the behavior of gold in grinding circuits and of the factors affecting the performance of the gravity concentrator (Laplante et al., 1995). Due to its high density (19.3 g/cm3 when pure) and malleability properties, gold tends to accumulate in circulating streams making it attractive for gravity recovery. The gravity recovery units are typically installed on a bleed stream of the cyclone underflow, mill discharge or cyclone feed."

Jan 1, 2011

1. ACKERMAN, C. L. The Binary System Manganese-Zinc. Ztschr. Metall., vol. 19, 1927, p. 200. 2. ADKENASY, P., AND KLONOWSKY, S. Über die Manganatschmelze. Ztschr. Elektrochem., vol. 16, 1910, p. 107. 3. AKTIEBOLAGET FERROLEGERINGAR (assignees). Method for the Manufacture of Manganese Alloys Poor in Carbon or Silicon or Else Manganese. British Patent 163262, Apr. 28, 1921; U. S. Patent 1480267, Jan. 8, 1924. 4. Method of Producing Manganese or Manganese Alloys Poor in Carbon or Silicon. British Patent 174923, Jan. 25, 1922.

Jan 1, 1934

Standard petrographic profiles for many Permian seams from New South Wales and Queensland have been drawn up. The standard profiles of seams of the same age and from one or more coalfields were used to compile an idealized or type seam sequence for those coals in which more than half the seam profiles were similar to one another. A marked similarity existed between at least 7 of the 10 type seam sequences formed.The configurations of the vitrite-plus-clarite contents of the plies of 95 per cent of the seams could be formed from different arrangements of 3 basic sequences. These were...

Jan 1, 1970

By J. K. Armstrong, C. Feyerabend

"As mines are constantly growing and expanding, so do the challenges for emergency response teams. They have to keep up with the pace set by current and future production techniques. Although mines have now reached depths of several kilometres and their dimensions and complexity are that of an entire city, mines rescue still must be able to reach the most remote areas within the mine in a swift and safe manner. The duration of breathing apparatus and physical human capabilities are limitations. Therefore, alternative methods have to be explored to extend the time under oxygen for mine rescue teams without putting additional stress on the team members. To address this global trend, Dräger, Goldcorp and PAUS have partnered to develop a mine rescue vehicle that allows mine rescue teams to travel for an extended period of time through a contaminated atmosphere without the use of breathing apparatus, thus extending the range of their mission. By applying currently available techniques, the safe expansion of mine production can be ensured, giving mine rescue teams the ability to respond to accidents in a safer and faster way. INTRODUCTION With the reduction of easily accessible natural resources, there is a global trend toward searching for higher ore grades underground and/or continually expanding mines underground to extend their lifetime. While in some areas this trend has just begun, in other countries mines are reaching depths or horizontal dimensions that pose extreme challenges (Codelco, 2016). These challenges include safety relevant topics, such as rock stability, heat and seismicity, but also more basic issues such as distances to the working face, which can become crucial considering the cost to develop a new shaft or decline. To overcome this, there is a growing interest in collaboration among various stakeholders to drive the development and support of deeper mines and tackle the complexity of underground mining. This is evidenced by the fact that several industry and research groups and networks have formed, e.g. the I2mine project in Europe and the Ultra-Deep Mining Network by the Centre for Excellence in Mining Innovation in Canada. Due to commodity pricing and the trend toward renewable energy, metal/non-metal mining will be the driving force behind this development."

Jan 1, 2019

By Henry A. Signore

The Appalachian coalfield, located in eastern Kentucky, Pennsylvania, Virginia and West Virginia, has been one of the most productive in the United States. Total production from the Appalachian coalfield during 1994 was 340.8 Mt (375.4 million st), or 37% of the 929 Mt (1 billion st) produced in the United States that year. This region contains various coal types from high- to mid-sulfur coal in Pennsylvania and northern West Virginia to low-sulfur, compliance steam coal and premium-grade metallurgical coal in eastern Kentucky, Virginia and southern West Virginia. The region&apos;s product is in high demand in domestic and export markets. Productivity continues to improve, resulting in the primary coal operators solidifying their market positions.

Jan 1, 1995

By C. Bazin

The separation of rare earth elements is a complex process that is industrially carried out using liquid/liquid extraction. Detailed flow sheets of solvent extraction plants for the separation of rare earth elements are rarely available in the literature which limits the opportunity to teach and test the application of data reconciliation, process optimization and control to these types of plants. The basis of a simulator for a rare earth elements separation plant is described in this paper. The simulator is used to adjust the organic phase and stripping acid flow rate in a separation circuit of heavy rare earth elements from light one?s.

Feb 27, 2013

By A. C. Wilson

In 1991, local prospector C. ?Mickey? Clement recovered at least three alluvial diamonds from the Michipicoten River. Two of these stones were sent to the Department of Mineralogy, Royal Ontario Museum, where they were identified as industrial grade diamonds with weights of 1.05 and 1.13 carats. Both stones were described as frosted and graphite-inclusion riddled. In 1995, prospector Sandor Surmacz and geologist Marcelle Hauseux discovered diamonds in bedrock approximately 20 km north of the Michipicoten River. An 18.1-kg bulk sample of a xenolith-rich lamprophyre, taken from an outcrop at the side of the Trans Canada Highway north of Wawa, yielded 1 macro diamond and 5 micro diamonds. All but one was gem quality (Sage 2000). Since then, more than 36 occurrences of diamonds in bedrock have been reported in an approximately 30 km2 area centred 20 km north of the town of Wawa. The occurrences are hosted within a sequence of unusual, Archean-aged, heterolithic breccias previously considered to have no economic significance. Ten kimberlite occurrences also have been confirmed in the Michipicoten greenstone belt in the last 5 years. Two of these kimberlites are diamondiferous. To date, expenditures on property acquisition and diamond exploration in the Wawa are estimated at $120 million (CAN). This paper summarizes the geological observations made on these occurrences and discusses including the relationship between the occurrences and the regional geology.

May 1, 2003

By H. J. Lechtenberg

Preliminary results are given of solvent stimulation of two wells producing viscous oil (14°-17° API) from the Tar zone in the Wilmington field, California. The solvent (coker oil, an intermediate refinery product) was injected into the formation, and after a soak period, the well was returned to production. Data are given on crude oil properties, solvent properties, determination of volume of solvent in the produced oil, rate of oil production before and after stimulation, volume of additional oil produced, and volume of solvent recovered. Although further study and improvement of the method arcs needed, cyclic solvent stimulation appears to be an unqualified success in one well and a moderate success in the other.

Jan 1, 1972