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By W. H. Holtzhausen

The purpose of this project was to compare two underground, batch coal haulers ? battery haulers and shuttle cars ? in order to determine the more viable machine to implement. The specific standards for battery haulers were investigated and compared to the requirements of shuttle cars in order to identify the unnecessary expenses related to the legal requirements that are attached to the machines. Costs such as running costs, capital costs, and maintenance costs were researched and compared over a typical life of machine. Average production rates and breakdown times were obtained and used to determine which machine would be more reliable in achieving the required annual production.

Jan 1, 2014

By Richard P. Reiff

"The Facility for Accelerated Service Testing (FAST) program has been involved in numerous rail wear tests since its inception in 1976. A number of specialized tools have been developed to aid in assessing specific performance parameters including gauge face wear, head height loss, metal flow, head area loss, hardness, and welded rail end batter. The layout of a test site, including position in curve, number of measurements per rail, and train operation must be properly controlled/monitored to provide valid wear comparisons.This paper will provide an overview of the above-mentioned tools and techniques. In addition, a summary of recent test results from FAST, including information on head hardened rail investigations, will be provided. A set of guidelines for establishing a revenue service field test site will also be provided to aid users in performing evaluations of their own.IntroductionBackground of Rail Wear Testing at FASTThe Facility for Accelerated Service Testing (FAST) located at the Transportation Test Center, (TIC), Pueblo, Colorado has been involved with testing of rail since program initiation in 1976. A huge data base of rail wear information has been gathered from FAST operations under a variety of rail metallurgies, lubrication conditions, and measurement techniques. Attempts at obtaining meaningful rail wear information from early (1976-1978) FAST rail wear data was hampered by two main factors: (I) measurement techniques were insufficiently accurate for the amounts of wear being experienced, and (2) the lubrication was not sufficiently controlled to obtain uniform conditions for a sufficient measurement time period.Subsequent test periods were operated with improved measurement techniques and controls that ensured statistically valid data. The policies and conditions that permit accurate rail wear assessment will be reviewed and outlined in this paper, along with some specific TIC and field examples that will allow the user to improve the accuracy of a field rail test on their own operating property."

Jan 1, 1988

By N. Abdel-Khalek, A. Youssef

The tailings from beneficiation of Florida phosphate ore contain considerable phosphate values. These tailings are currently discharged into large disposal areas. More than three million tons of P2O5 are discarded with the phosphatic slimes (clays) in Florida each year. These phosphatic clays not only create one of the most difficult disposal problems in the mining industry, but also represent a tremendous loss of P2O5. As the quality and quantity of Florida’s phosphate reserves diminish, recovery of phosphate values from these wastes becomes more vital. This will also significantly lengthen the life of these important phosphate resources. Thus, it is the goal of this study is to recover more than 80% of the phosphate values in phosphatic clays. A systematic study to characterize samples taken from inactive disposal area has been conducted. The data suggest that natural segregation takes place in the settling pond. In other words, coarser particles settle closer to the feeding point of the pond. Flotation tests were conducted using the +325 mesh fraction of samples obtained from sites close to the feeding point (sample# A) and further from that point (sample# B) and (sample# C) which is even further away from the feeding point. The results show the following: Sample# A gives the highest grade and recovery, followed by that of # B and then of # C. There is a great potential to upgrade sample# A where concentrates of high grade (68.9-70.1 % BPL or 31.5- 32.1% P2O5) and recovery (~86.6-95.4 %) can be obtained under the investigated operating conditions (1.0 – 2.0 kg/ton sodium silicate and 1.5—3.0 kg/ton collector mixture of fatty acid and fuel oil). The mineralogical and chemical analysis of all samples is presented in this paper for comparison. Only in this paper, the flotation data of (site # A) are discussed below.

Jan 1, 2002

Recovery of Precious Metals from Chloride Solution by Magnetite The development of environmental-friendly lixiviants as alternatives to cyanide and the increasing recycling activities to recover precious metals from waste materials have prompted researchers to find efficient methods and alternative sorbents to recover precious metals, such as Au and Pt, from aqueous solutions. This study explored the use of magnetite (Fe3O4) as a sorbent to recover Au and Pt from chloride solutions. Magnetite is a semiconductor and has the capability of transferring electrons both within the solid state and across the solid-liquid interface and has the ability to reduce metal species on its surface. The sorption of AuCl4- and PtCl62- from NaCl solution on commercial grade magnetite powder was investigated by batch-sorption experiments. The effects of pH, contact time, NaCl concentration and precious metal concentration on the recovery were studied. Sorption experiments revealed that magnetite exhibited selectivity towards other metals with the strongest affinity for Au. Both Au and Pt recoveries showed similar pH dependence curves, with peaks at pH 6 - 7. At this pH range, a maximum of 4.4 ¦mol Au/g Fe3O4 and 3.0 ¦mol Pt/g Fe3O4 were recovered after 24 h at an initial metal concentration of 0.05 mol/m3. Increasing the initial precious metal concentration increased the Au and Pt uptake amount by magnetite. It was also observed that the recovery decreased with high NaCl concentrations. The SEM images of the magnetite particles after the treatment showed that gold, which was confirmed by the EDX analysis, agglomerated and were deposited on Fe3O4 surface.

Sep 13, 2010

By J. H. Zietsman, S. Maharajh, J. Muller

In the chlorination process for TiO2 pigment production, blends of titania feedstocks such as ilmenite, synthetic rutile (SR), natural rutile, upgraded slag, and chloride-grade slag are reacted with coke and chlorine at a temperature of around 1000°C to form TiCl4 (the main product) and other waste metal chlorides. The TiCl4 is the main feed material for the TiO2 pigment-making process. Feeding different titania materials to the chlorinator affects the amount of coke and chlorine required for the process, the amount of waste generated, waste disposal costs, the amount of TiCl4 produced, and bed build-up rates. These factors influence the value of the feedstock. Generally, a higher TiO2 feedstock is more valued since less waste is generated and less reagents are consumed. To quantify the impact of different feedstocks on the chlorinator, a techno-economic model was developed to describe the chlorination process and estimate process variables at steady state. This paper describes the development of the model and studies in which the model has been used to quantify effects of using different feedstocks.

Jan 1, 2015

By M. A. Kujoana

Following on the design of good mining layouts and regional support systems, and the implementation of sound strata control practices, stope support is the ultimate strategy to combat the hazards of rockfalls and rockbursts. The primary function of stope support in intermediate and deep level mines is to stabilize the rock mass immediately surrounding stoping excavations, that is, the zone of fractured rock which behaves in elastically around stopes. Support design is a process resulting in a support system which is both practical and meets or exceeds by a factor of safety the requirements for a particular geotechnical environment. The aim of this project was to design a support system, which accommodates the factors of rockfalls and rockbursts. The pack support unit must be easily handled, less costly and can be used in stopes without any significant convergence. The project tested the structural stability of packs to their expected deformation, in order to design a height to width ratio for stopes where little convergence is expected.

Jan 1, 2009

By Göran Bäckblom

The Swedish mining companies LKAB and Boliden, the equipment supplier Atlas Copco, the general contractor NCC and the specialist company Reflex joined forces in 2005 to advance the field of rock technology for the purpose of mining and underground construction. The creation of the company Rock Tech Centre is part of the strategy developed by the Swedish mining industry to strengthen co-operation with industry, academia and society. This paper outlines the current R&D strategies developed for the industry in general, discusses what focus areas are selected and provides some details on the current RTC project portfolio, especially faster and better drifting.

May 1, 2006

By Bernard S. Borie

THE U-A1 binary system has been studied by Kaufmann and Gordon.' They have shown that three intermetallic compounds occur in the system: UAl², UAl², and a third compound tentatively identified as UA15. UA1³ is simple cubic, a, = 4.26A. Its unit cell contains one formula weight, and it is iso-morphous with AuCu³. UA1² is face-centered cubic, a, = 7.72A, with eight formula weights per unit cell. Rundle and Wilson have shown that it is iso-morphous with Cu²Mg.² A Debye-Scherrer pattern of the Al-rich compound indicated a more complex structure than either UA1² or UA1³. The following is a report of an investigation of the crystal structure of this compound and a determination of its stoi-chiometric formula. A melt of uranium (99.9 pct pure) and aluminum (99.9 pct pure) was prepared which contained about 25 pct U by weight. It was cooled from 950" to 650°C at a rate of 500" per hr and then taken from the furnace and air cooled. An X-ray diffraction pattern of the ingot showed only lines of aluminum and the Al-rich compound. Filings from the ingot were reacted with a solution of sodium hydroxide, producing a fine black powder, the diffraction pattern of which showed no traces of aluminum. A comparison of the Debye-Scherrer pattern of our sample with the data published by Kaufmann and Gordon1 showed that it is identical with the Al-rich phase which they reported. Single crystals were obtained by cooling the melt more slowly (about 50°C per hr). After reaction with sodium hydroxide, the crystals appeared as small black needles attached to the ingot surface. Cell Size, Space Group, and Uranium Positions A series of Weissenberg photographs for rotation about two of the crystallographic axes, taken with copper radiation filtered through nickel foil, revealed an orthorhombic cell of dimensions: a = 4.41 ± 0.02A b = 6.27 ± 0.02A c = 13.71 ± 0.03A Reflections of the type hkl were observed only if: h + k + I = 2n, of the type hkO only if: h = 2n and k = 2n, of the type h01 only if: h + 1 = 2n, and of the type Okl only if: k + 1=2n. Hence, the cell is body-centered with an 001 glide plane. The evidence for the existence of the glide plane is the observed extinction of 23 possible re- flections of the type hkO with at least one index odd. There are only two space groups consistent with these data: C"" — I2ma and D28 2h — Imma.³ he possible sets of atomic positions for these space groups are: 12ma: (0 0 0; ½ ½ ½) + 4: (a) x 0 %; x % % (b) x ¼ z; x ¾ Z 8: (c) x y z; x y z; x, ½ + y, Z x, M - y, z Imma: (0 0 0; ½ ½ ½) + 4: (a) 0 0 0; 0 ½ 0 (b) 0 0 ½; 0 ½ ½ (c) ¼ ¼ ¼; ¾ ¼ ¼ (d) ¼ ¾ ¾ ; ¾ ¾ % (e) 0 ¾ Z; 0 ¾ z 8: (f) x 0 0; x 0 0; x 1/2 0; x ½ 0 (g) ¼ Y ¼; ¾ Y ¾; ¾ y ¼; 1 y ¼ (h) 0 y z; 0; ;; 0, ½ + y, z; 0, l/2 - Y, Z (i) x 1/4 z; x ¾ z; ¼ z; x ¾ z 16: (j) xy z; x y z; x y z; x y z; x, ½ + y, Z; x,½ - y, z; x, ½ - y, z; 11 1, + y,Z Though density measurements on different samples were found to vary somewhat, they were all within the range 5.7 * 0.3 g per cu cm. If it is assumed that the unit cell contains four formula weights of UAl,, it is 6.5 g per cu cm. If there were as many as eight uranium atoms per unit cell, the

Jan 1, 1952

By I. C. L. Webster, G. E. Ray

"The magnetite-rich Heff Cu-Au skarn lies in the Quesnel Terrane of south-central British Columbia, approximately 26 km northeast of Kamloops. The skarn formed close to the northern margin of the Heffley Creek pluton, and is hosted by Carnian (Late Triassic) Nicola Group limestone. The Late Triassic pluton (208.1 ± 6.1 Ma, U-Pb zircon) is a composite body of alkaline affinity that includes dioritic, gabbroic, and magnetite-rich clinopyroxene ± olivine ultramafic phases.The skarn has been discontinuously traced along strike for more than 1 km, and individual skarn layers are up to 40 m thick. The most common non-opaque minerals are garnet, clinopyroxene, and carbonate, with lesser epidote, biotite, amphibole, and chlorite. Apatite locally forms more than 3 vol.% of the rock. Compositionally the garnet is a low Mn grandite averaging Pyr3-Grs41-Adr56 mol.%.Mineralization consists of lenses, up to 10 m thick, containing massive low Ti-V magnetite (avg. 0.03 wt.% TiO2 and 0.01 wt.% V2O3). Magnetite is associated with up to 20 vol.% pyrrhotite, lesser pyrite, and trace chalcopyrite and gold. There is a moderate enrichment in rare earth elements with assays up to 570 ppm La and 490 ppm Ce. The Heffley Creek pluton belongs to a suite of Late Triassic-Early Jurassic alkalic and Fe-rich intrusions that are widely developed throughout the Quesnel Terrane. Some host Cu-Au porphyry mineralization, but less commonly they are associated with magnetite-apatite veins such as at the Glen Iron mine and Magnet occurrence, or with magnetite-rich Cu-Au skarns such as the Heff occurrence.Although abundant low Ti magnetite is present in the Heff skarn, it does not appear to represent iron oxide copper- gold (IOCG) type mineralization. Microprobe analyses completed during this study show that low Ti magnetite is not a unique feature of IOCG deposits, but also characterizes some other types of hydrothermal mineralization. In British Columbia these include some alkalic porphyry-related magnetite-apatite veins in the Quesnel Terrane, as well as the well-known Wrangellia-hosted Fe skarn deposits. Thus, low Ti magnetite appears to be a common signature of many magmatic hydrothermal deposits in contrast to the high Ti primary magnetite found in most igneous rocks."

Jan 1, 2007

Appropriate roof control is the most important requirement in underground coal mining and, in the case of longwall panels or second mining in room and pillar extractions, this can be simply expressed in terms of good and predictable roof caveability. Studies of roof caveability have been undertaken in many coalfields around the world. Most of their conclusions. however, are directly related to the mining and geological conditions experienced in these areas and as a result, may not be applicable to the conditions encountered in the Appalachian coalfield. Furthermore, some of these studies appear to be theoretical and conceptual, ignoring many important parameters of the geological environment, whereas others rely heavily on geological information but lack a rigorous foundations upon which quantitative design guidelines can be built. The objective of this study is to analyze caving and mass deformation characteristics above longwall panels in Appalachia and includes: - Analysis of the effects of the geological and geomechanical characteristics of the strata on the caving height and the bulking of the caved-material. - Testing of the applicability of the various theoretical and empirical models of roof caving. Formulation of a numerical around- deformation model for ion-elastic material behavior.

Jan 1, 1986

Allis Mineral Systems ARCO Coal Company Buckley Powder Co. CALCO, Inc. Coal Magazine Colowyo Coal Company Continental Conveyor & Equipment Company Crane & Hoist Sales Cummins Southwest, Inc. Energy West Mining Company Paul J. Epley FMC Corporation The Falkirk Mining Company Fleischli Oil Co., Inc. T. J. Gundlach Machine Company Halbach & Braun Harnischfeger Corporation Hemscheidt Corporation Hyatt Regency Beaver Creek Jennmar Corporation Joy Technologies, Inc. K&P Sales Engineers, Inc. Kennametal, Inc. Kerr-McGee Coal Corporation McLanahan Corporation National Coal Association The North American Coal Corporation Northwestern Resources Company Peabody Coal Company Phillips Machine Service, Inc. Pincock, Allen & Holt, Inc. Pittsburg & Midway Coal Mining Co. Roberts & Schaefer Company Rust Tractor Company Salt River Project Santa Fe Pacific Coal Corporation Schroeder Industries Shearson-Lehman Brothers Southern Pacific Transportation Stamler Corporation Trapper Mining Inc. Wagner Equipment Company Western Energy Company Wheeler Machinery Company

Jan 1, 1992

By T Higuchi, L Lu

The quality of iron ore fines have been deteriorating, which has affected sinter quality and productivity adversely. New pretreatment and sintering technologies are therefore required to tackle the gradual change in the quality of iron ore fines. In the sintering process, iron ore fines are first granulated with fluxes such as limestone and coke breeze, and are then loaded and fired in a sinter machine. Sinter productivity and quality are heavily influenced by the reactions occurring in the sintering bed. Hence fundamental understanding of these high temperature properties of ores is urgently needed.Formation of initial sinter melt, penetration and assimilation of nucleus particles by the initial melt, and consolidation and final solidification of final sinter melt are believed to be the key sintering reactions. The assimilation and penetration phenomena have been studied separately in the literature with model particles and diffusion couples and are therefore difficult to relate to sinter quality. In addition, the effect of ore mineralogy has not been studied in detail.In this study, tablets consisting of coarse particles from various iron ore fines as nucleus particles and chemical reagents as adhering fines were made and fired under various sintering conditions to investigate the penetration and assimilation behaviour simultaneously. The degree of assimilation, pore structure, compressive strength of the resultant analogue sinters were evaluated and the relationship between sinter strength and ore characteristics was further discussed. The nucleus particles from Ores A and B were found to be more porous and assimilated more readily with sinter melt, resulting in a viscous melt and a macro-porous sinter structure. The nucleus particles from Ores C and D on the other hand, assimilated less readily with sinter melt, resulting in a fluid melt and a denser sinter structure. This is consistent with the results reported in the literature, suggesting that the present evaluation method can be utilised for studying sintering reactions and predicting sinter quality.CITATION:Higuchi, T and Lu, L, 2017. Evaluation of sintering behaviour based on ore characteristics, in Proceedings Iron Ore 2017, pp 303–308 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Two events during the past decade have combined to effectively alter the role of the geologist working in Papua New Guinea. The gold boom of the 1980s resulted in a substantial increase in the general awareness at village level of mining companies, gold and landowner issues, and as a consequence of the Bougainville tragedy, landowners are also very much aware of the potential problems of a mining operation in their area. Landowners know they have the power to remove a company from a project area, and government has shown itself to be virtually powerless and unable to help the company effectively. During a considerable proportion of a project's development time, the project geologist is viewed in the eyes of the local community as the 'company'. Good landowner relationships are nurtured over a reasonable time period and the input of the geologist is significant in determining the eventual fate of company-landowner relationships. The initial impressions of the company, gathered by the local community, will have a far reaching impact on the nature and direction of their future exchanges with the company.

Jan 1, 1991

By K Ehrig

You are a geologist, geometallurgist, or metallurgist/process engineer and are fortunate enough to work for an organisation who asks you to design/execute a geometallurgy program. What seems like a simple request is actually not a trivial exercise. æRecipeÆ style manuals are not readily available. However, many æexpertsÆ are lurking around willing to deliver solutions which will solve all of your problems. Even though similar ore deposit styles (e.g. porphyry Cu, IOCG, Ni-laterites, calcrete hosted U, etc.) have many similar characteristics, each ore deposit is unique. Hence your geometallurgy program needs to be æfit-for-purposeÆ. This paper offers some insights gained via designing and executing geometallurgy programs from exploration through to production, and working at a mine where you are held accountable for your metallurgical performance predictors.CITATION:Ehrig, K, 2013. Geometallurgy - What do you really need to know from exploration through to production?, in Proceedings MetPlant 2013 , pp 28-33 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Pooley F. D

The coal measures of the South Wales coalfield contain at least 50 horizons at which coal seams are known, to occur. More than 300 samples of coal were collected from these coal measures and this paper outlines thefindings of an investigation of the pattern and distribution of 12 trace elements in South Wales coals. A comparison of trace element contents of the South Wales coals is made with trace element values found elsewhereand an attempt was made to establish the organic affinity of the elements in different seams and in the coalfield 'as a whole. An important function of such an analysis is to determine the order of abundance of trace elements and this was performed for individual seams and for the whole coalfield.The interrelationship of certain elements in some seams is also examined with a view to understanding the effectiveness of such an approach to seam correlation.Ranges of values are quoted together with the mean values of the various elements. Variations of elemental values within a seam section and over the coalfield as a whole are discussed.

Jan 1, 1977

By Alan R. Buehler

The Bureau of Mines conducted a mineral investigation of the 177,000-acre Secesh study area; most of the area had been proposed as wilderness. Bureau personnel mapped and sampled several hundred mine and prospect workings; 1,715 rock, soil, and placer samples were taken during the investigation. The study area is centered about 25 mi east-northeast of McCall, Idaho, in the Payette National Forest. Five mining districts extend into or are adjacent to the study area. There have been more than 3,000 mining claims located inside the study area, 884 are current. In excess of $17 million (historical value) in placer and lode gold has reportedly been produced from the Warren district alone. The study area contains gold, silver, copper, lead, zinc, tungsten, and antimony. At least six properties that would be in the proposed wilderness contain gold resources; more than 18 million tons averaging 0.038 oz/ton gold have been identified. Additional resources may be located at 4 other localities. The 4th of July mine is currently producing gold/silver/lead ore. Similar resources may be located on at least 3 other properties. Placer samples from the study area contained up to 0.34 oz gold/yd3 ($120/yd3). The samples are representative of relatively small occurrences and do not constitute resources; small quantities of gold may be recovered by recreational placer miners.

Jan 1, 1993

Detailed petrographic analyses of coal seams from the Newcastle, Illawarra, and Lithgow Coal Measures were made for a number of localities for each of twelve seams. From these analyses characteristic standardprofiles were derived for each seam. Two broad types of profile were found; one in which vitrite-poor and vitrite-rich layers alternate, and another in which there is a steady decrease in vitrite from the base to the top of the seam. From comparison of the petrographic profiles it was concluded that the Great Northern Seam in the Northern Coalfield is a possible equivalent to the BulIi in the Southern; and likewise the Fassifern to the Balgowni...

Jan 1, 1967

By A. K. Snelgrove

At a time when water resource planning is proceeding on a continental scale, such as the proposed $100 billion North American Water and Power Alliance, which would redistribute water among three nations, including seven provinces of Canada, 35 of the United States, and three States of Mexico, the selection of a single river basin for study may seem to require an apologia. None is offered because of ( 1) the magnitude of the Indus , itself a part of the great Indo-Gangetic Plain drainage system, with Himalayan sources, upon which the thickly populated northern sub-continent of Indo-Pakistan depends for agriculture and hydroelectic power; (2) the extraordinary problems created by dismemberment of the world?s largest irrigation system through legal beheading of the Eastern Waters under the Indus Waters Treaty of 1960; and (3) the herculean effort to contain the twin encroachments of waterlogging and salinization in a basin which faces a shortage of fresh water. The British irrigation system of barrages and canals on the Indus was a venture admirable in conception. Unfortunately, it is now a legacy burdened with unwanted consequences, due to interference with the hydrological regimen, particularly the rise of water table occasioned by leakage.

Jan 1, 1967

By M. M. Fine

Research on the solid-fuel reduction of Knob Lake iron or was conducted to upgrade lean and high-grade ores and recover metallized products suitable for ironmaking or steelmaking. The program included bench-scale tests plus a number of continuous campaigns in a 34-inch by 36-foot rotary kiln. In the laboratory, metallizations in excess of 90 percent were achieved by reduction of crushed ore with lignite at 950° C. Subsequent grinding (to minus 200 mesh) and wet magnetic separation yielded concentrates analyzing less than 3.0 percent SiO2 and more than 90 percent Fe. Virtually complete recovery of the iron occurred. During early continuous tests the crushed ore created a serious ringing in the kiln which was solved by balling the fines with bentonite. Unfortunately, at this temperature (950° C) the bentonite militates against the concentratability of the metallized product. For example, a run on direct-shipping ore produced concentrates of 89.5 percent Fe and 4.5 percent SiO2. At 500° C the adverse effect of bentonite disappeared and concentrates of 88.4 Fe and only 2.5 percent SiO2 resulted. However, with comparable feed r Los, the metallization dropped to 73 percent.

Jan 1, 1969

In responding to why some longwall roadway development rates are different among mines, the Roadway Development Task Group (RDTG) of Australian Coal Association Research Program (ACARP) has initiated a benchmarking study to survey each longwall mine to determine the correlation between roadway development practices and roadway development performances. This paper describes a web-based relational database system which has been developed purposely to monitor the performance of Australian longwall roadway developments aimed at assessing both the physical and operational factors which could influence roadway development practices and their performance indicators. Statistical analysis of an earlier survey suggested that continuous miner units that achieved more than 1750 m were units mining two-heading development.

Dec 6, 2010