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By Ajay K. Jha1

Drilling and Blasting are two important unit operations in the production cycle of a mine and a strong link exists between these two and other unit operations/subsystems like loading, transportation, and crushing. Under the present concept of ? Mine to Mill?, it is important to optimize the drilling and blasting operations by applying scientific approach to drilling and blasting using sophisticated instruments and new technologies, which depends heavily on Information technology (IT) to meet this imperative. Development of innovative models and software has lead to blast optimization process. Till date, the blast results are evaluated in terms of available empirical approaches like powder factor, which are too simple to exclude some key parameters or lack in providing reliability because of non-availability of user friendly IT enabled techniques. Although with the help of developed approaches, formulation of user-friendly software to assist the site engineers in effective post blast assessment has started but there is a dearth of holistic approach to design an optimum blast considering the techno-economic feasibility of the subsystems and the geo-mining conditions to achieve blast optimization. The science of IT enablement in drilling and blasting is capable to build innovative models for achieving blast performances which will be doped with productivity, economy and safety with due regard to environment. The present paper discusses the use of existing IT enablement in various mines of India citing the Indian scenario and the future requirements for achieving the techno-economics in overall mining operations.

Sep 1, 2012

By Clarence Karr

RESINS from a bituminous pitch, a bituminous coal, a lignite tar, a subbituminous pitch, and an electrode binder pitch wore investigated by the Bureau of Mines. The compositions of these resins were determined by four independent methods of structural detemination: (1) Molecular formula and ring analysis, including ring (2) infrared and ultraviolet spectra; (3) combined pyrolysis/gas chromatography, and (4) catalytic dehyrogenation followed by spectra and pyrolysis. The resin structure was correlated with coal structure, and it was concluded that pitch resins probably consist of essentially unaltered coal molecules carried over with the tar vapors in low-temperature carbonization.

Jan 1, 1966

By L Köresaar, J Moilanen

With lower and increasingly variable Fe grades in iron ore resources, the monitoring of Si, Al, Mg and other light elements to meet quality requirements is gaining importance in the iron ore beneficiation industry. The high cost per manual assay and associated manpower requirements often limit the frequency of shift composite samples and laboratory assays. Furthermore, the shift composite assays represent past performance of a plant but are not useful for immediate reactions to feed variations, detection of equipment malfunctions or process control. Automated online analysis of light elements radically reduces the cost per assay and provides repeatable, timely data for process analysis, control and optimisation.A light element online slurry analyser, based on laser-induced breakdown spectroscopy (LIBS) optical emission technique, will be presented. This paper discusses the analyser design for the iron ore industry and also reviews the performance of the analyser against the manual laboratory. Additionally operator safety, user friendliness and maintenance requirements are discussed.A case study will also be discussed in this paper. The sophisticated measurement technique has been implemented in an industrial automated analyser and sampling system to allow for slurry measurement for up to 12 sampling points. However, careful selection of the sampling points and implementation of the sampling system is required for smooth operation.CITATION:Köresaar, L, Timperi, J and Moilanen, J, 2015. Optimised process control in iron ore via online analysis of light elements, in Proceedings Iron Ore 2015, pp 511–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By K. Svens, M. Lahtinen, L. Lehtinen

"Outotec's direct leaching process is an atmospheric leaching process for sulphidiczinc concentrates. The direct leaching process, based on special leaching reactors developed by Outokumpu and leaching know-how, is the most economical way to produce electrolytic zinc. The newest industrial-scale application of Outotec's direct leaching process will be started up in 2008 in China at Zhuzhou smelter. The process isintegrated to the existing production plant, replacing part of the old production facilities by modern technology and increasing the production capacity significantly. The process equipment supplied by Outotec includes also tailor-made reactors designed on the basisof the work and experience of Outotec Research Centre."

Jan 1, 2008

By Michael E. Henderson

The U.S. Bureau of Mines (BOM) constructed the Hydraulic Transport Research Facility (HTRF) to investigate the hydraulic parameters relating to the transport of coarse coal. To achieve these goals in a timely and efficient manner, the Bureau contracted to Boeing Services International (BSI) the responsibility of operating the HTRF and providing technical support. This data report is a summary of the testing and data results for the period 22 November to 10 December 1982. The testing covered herein is for coarse 2-in by 0 (minus 50 mm) Pittsburgh Seam coal in a 6-in (150 mm) pipeline, at velocities ranging from 5 to 20 ft/s (1.5 to 6.1 m/s) and at concentrations ranging from 15 to 45 pct by weight.

Jan 1, 1986

From a distance, the 0.75-km (0.5-mile) rail line that sits in the shadows of Vale-Inco?s Stobie Mine outside of Sudbury, Ontario could be mistaken for a standard conveyor belt hauling ore from the nearby mine. But with its large, yellow-painted loop and interconnected green rail cars that invert themselves on the loop before correcting with a smooth rollover further down the track, one might assume that this is some sort of test track for a new roller coaster. The fact of the matter is that it is the proving ground for Rail-Veyor technology, a technology that the company hopes will one day change the face of ore transportation in surface and underground mines around the world. With a line of linked, low-profile rail cars that are capable of carrying up to 1 t (1.1 st) per car of ore by way of simple, above ground, lightweight rail track, the technology is not groundbreaking. In fact, it was developed in the 1960s for the French State Railroad. A demonstration plant for the Florida Institute of Phosphate Research was installed in 2000 and the first commercial under-ground installation was in 2007 in South Africa at Harmony Gold?s Phakisa Mine. There, a 4.7-km- (2.9-mile-) long tram between two shafts operates three Rail-Veyor trains on a shared track. The difference is that the application that is being tested day-and-night in Sudbury is getting closer to wide production, thanks to the use of computer controlled automation that has helped turn an old idea into a cost-effective modern solution.

Jan 1, 2010

By R. Farrar

The survey work on protective canopy design was conducted in a 2-month period commencing November 15, 1973. The reported re¬sults under this contract are intended to provide guidance to coal mine operators in complying with federal regulations pertaining to incorporation of protective canopies on underground coal mine electric face equipment. All coal mine electric face equipment manufacturers and 11 coal mines were visited in the course of conducting this survey. Canopy designs currently being manufactured and those now being used underground were examined and discussed with manufacturers, mine operators, machine operators, and safety committeemen. The general objective was to find out what kind of canopies are now being made and used underground, what the operational problems are, and what can be done to secure improvements. Specifically, the survey scope was as follows: a. Survey all electric face equipment manufacturers. b. Survey 10 coal mines (seam height 60 inches and greater). c. Identify current production canopy configurations and minimum mine entry dimensions for each model and type of electric face equipment. d. Assess in-mine operation of canopies developed by manufacturers and/or coal companies. e. Specify optimal canopy configuration and minimum mine entry dimensions for each type and model of electric face equipment.

Jan 1, 1974

By J. A. Kinnaird, B. J. Youlton, K. L. Youlton

Methods for treating and processing refractory gold ores are well established. However, what is less well understood is how the formation of the gold-bearing deposits affects gold processing and extraction. In order to evaluate the effect of ore genesis on gold extraction a number of South African gold deposits were studied. These included complex Pilgrim’s Rest samples as well as refractory Fairview, Barbrook, and Consolidated Murchison samples. We found the refractory nature of gold ores is controlled by a limited number of well-understood mineralogical factors. Solid solution gold is linked to low temperature and pressure conditions in fine-grained sedimentary lithologies, while reactive pyrrhotite can form from hydrothermal fluids associated with mafic magmatic rocks. These formational controls can be used to identify and avoid complex deposits at a desktop study phase, or address and reduce complications further along the pipeline using early mineralogical studies.

Jun 1, 2021

The following is an incomplete list of members and guests who called at Institute headquarters during the period Jan. 10, 1918 to Feb. 10, 1919. Walter F. E. Barcus. Lt. C. K. McDonald, U. S. N. R. F. Capt. D. H. Bradley, Jr. Major John DeN. Macomb, Bayhead, N. J. Melvis Buigger. - Samuel Melitzer, New York City. Eugene Coste, Calgary, Can. T. C. Merriman, New Haven, Conn. C. W. Cromwell, Warren, Ariz. Wm. J. Millard, Tulsa, Okla. E. O. Daue. Benj. L. Miller, Bethlehem, Pa. Capt. H. W. Edmondson. S. B. Patterson, Jr., Allentown, Pa. E. W. Engelmann, Hayden, Ariz. Lynn L. Pomeroy, New York City. C. Mason Farnham. W. E. Pomeroy, New York City. Lt. C. W. Frith, Salt Lake City, Utah. G. M. Ponton, Ottawa, Ont. John T. Fuller, Honesdale, Pa. Wallace E. Pratt, Ft. Worth, Tex. Walter A. Funk, Idaho Sp., Colo. Harold L. Rau, Milwaukee, Wis. Major W. R. Grunow, New York, N..Y. Lt. E. J. Ristedt, Camp Merritt. A. W. Hackwood, Butte, Mont. George M. Ryall, Los Angeles, Cal. Lt. Nathaniel Herz, New Haven, Conn. D. B. Scott, Mogollon, N. M. Ralph T. Hirsh, New York City., W. H. Staver. O. P. Hood, Washington, D. C. Douglas B. Sterrett, Washington, D. C. E. B. Hopkins, Houston, Tex. J. A. Stewart, Minneapolis, Minn. Hugh C. Ingle, Pensacola, Fla. R. H. Summer, Wilmington, Del. Capt. Wm. F. Jahn. W. G. Swart, Duluth, Minn. Roswell H. -Johnson, Pittsburgh, Pa. Kirby Thomas, New York City. Jesse L. Jones, Pittsburgh. Pa. Capt. H. D. Trounce, San Diego, Cal. Edgar Kidwell, Berkeley, Cal. L. Unger, New York City. .D. H. Ladd, Detroit, Mich. George F. Vivian, Butte, Mont. Raymond B. Ladoo, Cambridge, Mass. R. A. Walter, Reading, Pa. W. H. Landers. Lt. R. G. Wayland, Chehalis, Wash. David Lasner, Elizabeth, N. J. R. J. White, Wallace, Idaho. J. M. Lilligren. J. S. Wroth, Albuquerque, N. M. Lt. Wm. J. Linn, Chicago, Ill. Herbert Hoover, General Pershing, Ambassador William G. Sharp and Admiral William S. Benson were speakers to-day at the annual luncheon in honor of Washington's Birthday, given by the American Club of Paris at the Palais D'Orsay.

Jan 3, 1919

By Pengfu Tan

In order to understand and control the formation of dioxins and furans in iron ore sinter plants and to possibly avoid expensive end-of-pipe removal stages, thermodynamic calculations on the stability of PCDD/Fs have been combined with sinter process modeling by means of kinetic simulations and computational fluid dynamics. Three thermodynamic databases of PCDD/Fs, derived using the Group Additivity approach and two computational molecular modeling methods, MNDO and PM3, respectively, combined with the SGTE database have been used to model the PCDDIF formation and the PCDD/F isomer distributions in iron ore sintering. The results show very similar conditions for the PCDD/F formation using the different databases. Concerning the isomer distributions of toxic PCDD/Fs, the calculated data derived from the MNDO method showed optimum agreement with measured values from industrial furnaces. The thermodynamic calculations also proved that the isomer distributions found in combustion processes are equilibrium values, while the concentration ratio of PCDDs and PCDFs in the wind boxes does not represent an equilibrium state. A CFD model of iron ore sintering was developed including the kinetics of 15 relevant chemical reactions with the aim of describing the temperature fields and the gas flow patterns in the sintering bed. On the basis of these information and experimental observations reported in the literature possible pathways for the PCDD/F formation in sinter plants have been identified: PCDD/Fs are formed in the critical temperature region of 250 to 450°C below the combustion zone, are then carried downwards with the gas and condensed close to the bottom of the sinter bed. Transported to the discharge end with the solid mixture, they are again released into the gas phase when the flame front approaches the bottom. PCDD/Fs are also formed in the last wind boxes when the hot off-gases cool down and reach the critical temperature range. Consequently, methods to reduce the dioxin formation reactions are proposed including inhibitor addition to the sinter feed and off-gas quenching.

Jan 1, 2003

By BHAMIDIPATI S. SASTRY, SRIVATSAN J. SRIDHARAN

Pressure losses in mine ventilation systems are estimated using friction factors and shock loss factors. The efficient planning and designing ofmine ventilation systems depend on the accuracy of the friction factors as well as the shock loss factors that are taken into consideration. While there is a much more acceptable knowledge of what constitutes friction loss in mine roadways, the shock loss factors are in general readily not available for all possible contexts of flow separation phenomena in mines. One such special case of shock loss in mines is the train of mine cars in the airway. Mine cars are widely used for the transportation of material, and the information on shock loss factor for mine cars is limited. This paper examines the pressure loss occurring due to a train of mine cars in an airway using scale model studies and numerical investigations. Computational fluid dynamic (CFD) studies are conducted using four different turbulence models. The performance of different turbulence models is analyzed by comparing it with the experimental results. The study suggests that the boundary layer resolution method is significant in the simulation of shock loss. From the study, it is found that the shock loss factors from presently available model overestimate the pressure loss by 7 to 15 times. A better prediction model for the shock loss factor of a train of mine cars in the airway is proposed using the experimental results.

Jul 24, 2020

By E. M. Cameron

Reconnaissance radiometric and geochemical data have been obtained for an area on the western shore of Wollaston Lake that includes the Rabbit Lake uranium deposit. The study area is extensively drift cover ed. The geochemical data were obtained by analysis of center-lake sediments and surface waters for a variety of elements and other constituents. The airborne radiometric data comprise measurements of eU, eTh and K obtained with a .50,000-cc NaI (Tl) detector at a mean terrain clearance of 120 m and 5-km flight-line spacing. Uranium in lake sediments and uranium in waters are the most effective geochemical indicators of uranium mineralization; the other elements measured are not notably anomalous. A sample site density of one per 1 8 km 2 is more than adequate for identification of the mineralized area. Because many water samples contain close to or below the current analytical detection limit of 0.05 ppb U, the use of sediments is generally favoured. for broad-scale reconnaissance in the region. Uranium in these lake sediments appears to be little influenced by variations in the organic or iron and manganese content. The most effective radiometric indicator of the mineralization is the eU/eTh ratio. This parameter is less influenced by environmental variation on the ground beneath the flight line than eU alone . The eTh/K ratio is anomalous under the Athabasca Formation unconformity where, in places, the uranium mineralization is localized.

Jan 1, 1977

By G. Paul Anderson

Personnel at Utah Copper Division's Bingham Canyon Mine use current computing technology to compile pertinent production statistics and mining plans. Within hours after the day's work has been completed, concise reports summarizing the previous day's production statistics, actual production vs. budget statistics, the location of shovels relevant to the mining plan, the performance of equipment, equipment next scheduled for maintenance, etc. are available at the terminals located throughout the mine. Also, engineering personnel us e computerized systems, directly from their offices, to assist them in the timely development of mining plans. Timely and concise reporting and planning capabilities such as these assist mine personnel in their efforts to review mining progress and equipment performance, and as such they are in a better position to detect adverse trends early and to seek appropriate resources or make changes in plans or practices.

Jan 1, 1977

By C. Harry Benedict

This paper presents the details of milling practice and costs at the conglomerate mill of the Calumet & Hecla Consolidated Copper Co., Lake Linden, Mich., and is one of a series on milling methods being published by the Bureau of Mines. GENERAL DESCRIPTION The mines of the Calumet & Hecla. Consolidated Copper Co. are located in the Keweenaw Peninsula of northern Michigan. The mines of this district lie in a belt not over 4 miles wide and 100 miles long, which contains more or lees commercial ore. The Calumet & Hecla properties are the farthest north, except for the Seneca, of the operating mines. The district borders on Lake Superior, and by means of the Portage and Torch Lake waterways the largest lane vessels, can transport coal and other supplies from the lower Lakes directly to the company docks.

Jan 1, 1930

By A N. Danoucaras, S E. Goater, D Hearne, A M. Bansuan

It is globally recognised that existing and emerging mining activities should be conducted in a æsustainableÆ manner for the entire life of mine. Many companies annually publish corporate sustainability reports to demonstrate their actions in accordance with international expectations. This concept of sustainable mining practices also applies to mine water management, with influences often extending beyond site operations, affecting surrounding catchments and community users. This paper explores differences in conceptual and operational terms of æsustainableÆ mine water management within the Philippines. Outcomes of a review of corporate sustainability reports, governance documentation, research programs, and stakeholder knowledge acquired through action-research workshops are presented. The paper aims to inform and support future capacity building exercises delivered by the International Mining for Development Centre (IM4DC), with outcomes tailored to government officials and policy makers of developing countries. The project is funded by IM4DC, which is working with AusAID to identify needs and develop capacity with regard to mining for development; specifically, issues pertaining to governance and regulation, social and environmental sustainability, and operational effectiveness in developing countries.CITATION:Bansuan, A M, Goater, S E, Danoucaras, A N and Hearne, D, 2012. Integrated sustainable water management in mining for development in the Philippines, in Proceedings International Mine Management 2012, pp 205-226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By Hiroyuki. Fukuyama

The pseudo-binary phase diagram of the cuspidine (3CaO2?SiO2?CaF2) - CaF2 system has been studied by electron probe microanalysis (EPMA) and X-ray diffractometry (XRD). To prevent fluorine loss in the form of a HF gas by a reaction of CaF2 with water vapor at elevated temperatures, the equilibrium experiments were conducted with the sample hermetically sealed in a platinum tube. By employing this technique, it was successfully revealed that cuspidine exists as a stable phase and congruently melts at 1684 ± 1 K, and the cuspidine - CaF2 system presents a simple eutectic type of phase diagram, of which eutectic temperature has been estimated to be around 1540 K, corresponding to the composition of 40 mass% 3CaO?2SiO2 - 60 mass% CaF2?

Jan 1, 1999

By Theodore L. Turner, Joseph H. Swift

A study on a small laboratory scale was made of the use of ammoniacalammonium carbonate for batch leaching Mn from low- grade manganiferous materials ( 6 to 16 pct Mn) obtained from deposits in the southern district of Aroostook County , Maine . These materials were partially reduced at 500 ° to 700 ° C with H₂ or CO and then leached with solutions of NH and CO₂ dissolved in water . Extraction of 80 to 90 pct of the Mn was obtained from some sample materials , but 10 to 34 pct of the iron was also extracted . Material from the Littleton Ridge deposit contained manganese intimately associated with Fe , a condition which contributed to difficulties in obtaining a commercially acceptable product . Extensive investigations of the leach and reduction processes with various mixtures of H₂ and water vapor , and CO and CO₂ , failed to disclose a set of conditions for selectively leaching the manganese . Finely divided metallic Fe was probably produced during the reduction steps so that Fe was leached with the Mn in the subsequent extractions .

Jan 1, 1964

By J. W. Scott

The problems involved in installing, maintaining, and operating large vibrating screens have been summarized and discussed, based on a survey of current use of such screens in selected North American mineral processing applications. Practical, effective solutions for the more serious common problems are described, along with some recommendations on design practice for specifying, selecting, and installing large screens.

Jan 1, 1983

By R. Wensel

A composite material consists of two or more dissimilar components. These dissimilar components retain their identities when mixed together and contribute to the properties of the composite. A composite usually consists of two parts, the matrix and the reinforcing material, or extender that is added to the matrix. Typical materials used as the matrix in composites are metals, polymers, and ceramics. The reinforcing material can be added for any number of reasons. For instance, if the matrix is expensive, an inexpensive filler may be added to the matrix to lower the cost of the product without sacrificing properties. An example of this is calcite (CaC03) which is added to systems such as polyvinyl chloride (PVC), to lower the cost. Reinforcements may also serve as a means to enhance the properties of the matrix material. For example, carbon fibers are frequently added to plastics to increase their strength, and glass spheres may be added to plastics to improve flexural strength. Mg(OH)z is added to polymers to give the property of fire retardancy. The latter is the focus of this paper.

Jan 1, 1995

By Bernard Lewis

The ignition problem: for a layer of firedamp bordering on a cloud of detonation products is evidently considerably more complicated than in the usual laboratory ignition experiments, in which a well-defined volume of gas is heated and the occurrence of ignition is observed after an induction period. An atmosphere of firedamp exposed to the detonation of a high explosive is subjected to heating by shock-wave compression and thermal conduction and to intermixing at the interface of the firedamp atmosphere and the cloud of deto¬nation products. Although a reliable physical-chemical analysis of the problem is not yet possible, one may nevertheless form a general view of the role of compression waves and the processes of heat transfer and diffusion at the interface. Near the mouth of a shot hole, or near a freely suspended cartridge, the firedamp atmosphere attains very high temperatures by adiabatic compression, and it is certain that such temperatures are sufficient to initiate chemical reaction. The pressure wave pattern is reproducible from one test charge to another if the initial experimental conditions are held constant; on the other hand, experiments on firedamp ignition do not yield a reproducible threshold condition for ignition, but only an ignition probability. Thus, the induction periods are sufficiently long that there is time for the compressed', heated gas layers to undergo random changes that may quench or promote ignition. Therefore, the analysis of the ignition problem hinges primarily on the discovery of the random events that modify the chemical reaction in the activated gas layers.

Jan 1, 1948