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By G. P. Kundargi

India is one of the fastest growing economies in the world. The role of the Iron & Steel industry is very important for the development of the country. Iron and steel are among the most important components required for the infrastructure development of the country. This is one of the fastest growing sectors. The demand drivers for the Indian Iron & Steel industry are increase in the activities of the manufacturing industry and infrastructure development. Indian Iron & Steel industry with its strong forward and backward linkages contributes significantly to overall growth and development of the economy. The industry today directly contributes 2% of India?s Gross Domestic Product and its weightage in the official Index of Industrial Production (IIP) is 6.2%. Manganese is a main ingredient for production of steel. Almost 90% manganese is being utilized by the steel industry worldwide. Globally, there is no substitute for manganese as on date. There is huge gap between demand and production of manganese ore in the country. To meet this demand gap and to support for growth of national economy, MOIL Limited (formerly Manganese Ore India Limited), a Government Enterprises, producing annually around 1.1 million tonnes (mt) of manganese ore and value added products, has geared up with various infrastructural activities to increase the present production capacity of 1.1?1.5 mt in 2016?2017 and 2.2 mt in 2020?2021. The paper deals with the technological improvements and infrastructural development activities of MOIL; this will help MOIL to become the market leader in manganese ore production globally in the coming years.

Aug 1, 2013

By L. C. Hsu, H. F. Jr. Bonham, M. O. Desilets, P. J. Lechler, J. G. Price, L. J. Garside

Abstract-Geochemical background levels have been established for unmineralized sedimentary rocks that are elsewhere the hosts of Carlin-type gold deposits in the Getchell Trend. The Paleozoic rocks in the Winnemucca Quadrangle consist predominantly of the lower Paleozoic siliceous and clastic sequences that were carried eastward along the Roberts Mountains thrust during the Late Devonian and Early Mississippian Antler Orogeny and the late Paleozoic Havallah and Pumpernickel sequences brought along the Golconda thrust eastward during early Mesozoic Sonoma Orogeny. Over 260 rock samples were collected from the Paleozoic sequences. Major and trace elements were determined by instrumental methods best suited for the specific elements. The general geochemical features of the Paleozoic sedimentary rocks are discussed in detail with reference to the data of average abundances of elements in sedimentary rocks. The background and threshold values of certain trace elements in sandstone, shale, and carbonate rock of one formation, as well as back- ground levels for the entire sequence were obtained. The characteristic geochemical features of the Paleozoic rocks in this area include: consistently high Ba and low Au contents (1.1 ppb, 1.5 ppb, 1.1 ppb Au for average sandstone, shale and carbonate, respectively); generally low contents of those elements which may be of environmental concern such as As, Cd, Hg and Pb. Plots of major and trace elements suggest that the majority of the Paleozoic clastic rocks are related to a passive- margin tectonic setting. Samples with gold values higher than threshold are considered to have been affected by hydrothermal alteration related to gold mineralization. Most of these samples generally also have higher values of Sb, Hg, V and/or As. These observations support the use of such elements as pathfinders for gold, although V has not been identified as such before. Ba is not effective for gold exploration in this area due to the generally high background value of Ba, even though it may be an important pathfinder elsewhere.

Jan 1, 1995

By I. Bakry

Uncertainty is an inherent characteristic of construction projects. Neglecting uncertainties associated with different input parameters in the planning stage could well lead to misleading and/or unachievable project schedules. The objective of this paper is to present a new approach towards scheduling repetitive construction projects while accounting for uncertainty. The paper presents an algorithm that quantifies anticipated delays resulting from different sources of uncertainty in the form of fuzzy time buffers. Through inserting the time buffers in strategic places in a time schedule, the algorithm provides protection against those main anticipated delays. The presented algorithm comprises two integrated components, a scheduling component responsible for producing a basic Linear Scheduling Method (LSM) schedule with deterministic activity durations, and a buffer component that handles fuzzy buffers sizing and insertion. The presented algorithm offers four different buffer insertion techniques covering different cases of interrelations between successive activities. The algorithm is implemented in a spreadsheet application, which automates calculations, yet allows users to fine tune the algorithm to fit the project at hand. With a focuses on highway construction projects as an example of repetitive construction projects, this paper accounts for sources of uncertainty such as weather, site conditions, change orders and equipment related delays. A hypothetical case is studied and explained to further demonstrate how the proposed algorithm works.

Aug 1, 2013

By C. Bernier

This paper deals with three major problems associated with mining operations during the winter. These are the maintenance of the cooling systems of diesel engines, the high incidence of hydraulic dump failures on packaging machines, and the build-up of frozen fines on wet-ore conveyor belts.

Jan 1, 1966

By Garth D. Kirkham, James P. Siddorn, Hendri Falck

"Abstract - As an integral part of the Geological Survey of Canada’s EXTECH III Project, a threedimensional computer model has been created of the Con and Giant gold mines in the Yellowknife Greenstone Belt. The Yellowknife Mining Camp has produced a great deal of gold (over 15 million ounces, or 400 000 kg) in the past sixty years and the prevailing assumption is that the mines are at the end of their lives. However, the potential for discovering additional resources using new ideas and technology, and maximizing use of existing data, offers an opportunity to sustain the old mining operations and maintain their contribution to the community.The objectives of this study included the compilation and creation of a three-dimensional Geographic Information System model (combining 3D subsurface data with surface information) to provide a framework for concurrent structural and alteration studies, and to encourage new exploration in the area. A secondary objective was to retain the data in digital format as a historical reference for future remediation efforts, and to document a portion of Canada’s rich mining history.The end result is a database and set of models that have been instrumental in facilitating further exploration in the area, as well as in developing targets for future exploration and mining activities. In addition, the EXTECH III 3D GIS model has made a valuable contribution toward the understanding of the arsenic remediation issues at the Giant mine, and has served as a tool in support of a variety of highly technical engineering studies and for communicating information and problems to the layman and community as a whole."

Jan 1, 2003

By Anthony P. Makuch

Dynatec Corporation is an integrated mining services company, providing mine development, operations management, engineering, drilling and metallurgical services to the North American mining industry. Dynatec was the contract operator of the Ken Snyder Mine in Midas, Nevada from start of production in January 1999 to September 2001. This paper summarizes Dynatec?s experience and approach to the use of longhole stoping methods for mining to widths of 1.3 to 2 metres in a steeply dipping narrow vein orebody.

Oct 1, 2001

By J. F. Magee

THERE is nothing new about drag-line dredging for placer gold. The use of the separate unit for excavating preceded the large barge with bucket-line excavator mounted upon it, which has developed to a high state of perfection through use in every part of the world. But at present there is a vogue for a small, inexpensive plant to work economically the shallower gold gravel deposits that the bucket-line dredges do not work. The dragline dredge consists of the drag-line excavator, on caterpillar mounting on the edge of the dredging pond, which feeds the gravel to the washing plant, mounted on a floating barge in the pond. There have been more than twenty-five such plants built and operated in central and northern California and an unknown number in other States. There have been variations in details of design but the essentials are similar in all. I wish to describe the operation of a typical drag-line dredging plant, that of the Wyandotte Gold Dredging Company on the Farnan Ranch in the Oroville district. This organization of six active partners built their first plant on Wyandotte creek in the autumn of 1933. The operation was successful due to wise management, which was based upon good plant design and proper principles of operation. The partners elected one of their number, H. F. England, as manager with full control and responsibility. This plant and operation furnished the pattern for many subsequent ones.

Jan 1, 1937

By John A. Dresser

At a meeting of the Montreal Branch of this Institute in the autumn of 1928, the Honorable J. E. Perrault, Minister of Mines for Quebec, announced his intention to enlarge the Bureau of Mines of Quebec by the addition of a Division of Geology. The announcement further stated that the geological work proposed should be begun in the following field season, and that it should be on a substantial scale of not less than six field parties. The announcement was received with enthusiasm and much encouragement was held out for the success of the effort. It has been thought that the present meeting would be a suitable occasion to present a report of progress of this Division for the three years that have since elapsed. History This, of course, is not the first geological work to be undertaken by the Bureau of Mines. Prior to the establishment of the Division of Geology, the Bureau of Mines had not been unmindful of the need of geological research, but it had always lacked the means necessary to any sustained work. For more than 25 years the late J. Obalski was the Superintendent and the sole occupant of the Bureau. Yet, even then, Obalski, besides routine visits to mining districts, made a few exploratory trips along the north shore of the St. Lawrence river and one to Chibougamau, but without the equipment necessary to effective results.

Jan 1, 1932

By M. Abdollahi, M. R. Khalesi, Y. Kianinia, A. Khodadadi Darban

High cyanide consumption during the processing of gold ores with high sulphide minerals can make the typical cyanidation uneconomic. Also cyanide is a toxic material and environmental concerns of cyanide compounds are serious. Optimization of cyanide consumption requires a methodology to estimate the amount of exposed cyanicides, the kinetic of their dissolution and estimation of formation of cyanide complexes which consume the free cyanide. In this paper, a methodology to estimate cyanide consumption by modeling the minerals and gold leaching kinetic based on a liberation model and speciation of all possible cyanide related species in the solution is presented. The results showed that this methodology could successfully estimate the cyanide consumption based on mineralogical data with very lower number of parameters compared to empirical models present in the literature, while it offers the prediction of formation of all cyanide complexes which could be used for optimization purposes.

Jan 1, 2017

The AG/SAG circuit discharge P80 is now increasingly referred to as the “Transfer Size” or T80 for short. From the literature it is apparent that in circuit design some approaches to the sizing of AG/SAG mills as well as the ball mills that they feed use this parameter. This paper reviews whether the use of the T80 is appropriate in this context. In the course of the review examples of AG/SAG discharge size distributions measured from range of operating circuits are used to illustrate the arguments made.

Jan 1, 2012

By James Dickson

Brief History of Discovery and Early Development In the first half of the nineteenth century, the only authority on the Pacific coast between the Columbia river and Alaska was exercised by the Hudson's Bay Company, who had established a series of forts and trading stations on the coast from the Columbia north to Millbank sound. The Hudson's Bay Company were chiefly interested in the fur industry, and the large influx of settlers from the eastern United States into the territory now known as the States of Oregon and Washington, about 1840, not only interfered with the fur business but involved the question whether the territory should be under the British or the American flag. Anticipating the possibility, later realized, of losing control of this area, the Company, in 1845, established their main fort and trading centre on the southern end of Vancouver island under the name of Fort Camosun; shortly afterwards changing the name to Fort Victoria. Realizing that their former policy of discouraging all attempts to develop any other business than the fur industry had lost them several hundred thousand square miles, the Hudson's Bay Company now set about encouraging settlers in the vicinity of Fort Victoria by disposing of lands to suitable parties and also to those in the employ of the Company. The usual pioneering stage was passed through with the starting of small sawmills, grain mills, etc., and the incidental work accompanying such efforts. Any coal required for blacksmithing or other purposes was brought from England around Cape Horn by the few ships that visited the Pacific Coast. About 1849, an Indian who was having his gun repaired by a blacksmith in Fort Victoria asked about the "black stones" used in the fire and, on being told that the "black stones" had to be brought a great distance, he informed the blacksmith that there was plenty of the same stone where his people lived. This information was immediately given to an official of the Hudson's Bay Company who talked with the Indian and told him that if he would bring some of the "black stones" he would get his gun repaired free and a present of a bottle of rum. Nothing more was heard of this coal until April of the following year, when the Indian came into Fort Victoria with his canoe loaded with coal, which was tested and found to be of good quality. It is reported that the Indian got his bottle of rum.

Jan 1, 1935

By E. E. Mueser

As Mr. Lundberg has already ably covered the theory of various methods of electrical prospecting, I shall confine my remarks to a consideration of the features which must obtain in an electrical prospecting method in order that it may be useful from a practical standpoint. These remarks I shall make with particular reference to the Elbof method. The successful application of all these methods rests, in the first place, upon the possibility of correlating theory, or empirically established facts, with the field data. Their practical usefulness, however, requires that the technique of making the field observations, and the procedure itself, be such that the method may be applied to large areas, under normal average conditions. The method, therefore, should not involve excessive preliminary labour costs to prepare the ground for actual prospecting work, nor should the prospecting work itself be so slow that its cost, when applied to extensive areas, becomes prohibitive. Moreover, it should be possible to apply the method even under difficult terrain conditions, such as rough topography and dense vegetation. It may be said of most of the methods referred to in the preceding paper, that, while they are interesting and theoretically sound, they fail to meet such practical requirements as I have outlined.

Jan 1, 1926

By Mario E. Rossi

Geostatistical conditional simulations are becoming increasingly popular as tools that provide models of uncertainty at different stages of a mining project. They have been used as grade control tools in daily operations, to assess the uncertainty of minable reserves at the project?s feasibility stage, and to assess mineralization potential in certain settings. Other applications include assessment of recoverable reserves, resource and reserve classification, and drill hole spacing optimization studies. All large-scale applications of conditional simulations intend to benefit from the ?correct? (or ?accurate?) characterization of uncertainty, adequately describing the variability observed from the data and its impact on the final objective. The objective of this paper is to compare the ad-hoc ?uncertainty model? provided by a traditional classification scheme with the probability intervals resulting from a conditional simulation model. It is argued that the uncertainty model derived from the use of classification schemes is of little practical use to the mining company or operation. The paper emphasizes differences in uncertainty based on the size of the mining unit considered and the extraction method, and local geological differences. Most importantly, it discusses confidence intervals for these mining units, as compared to the relative precision envisioned by a typical classification scheme. The application described in this paper is taken from a medium-sized Cu open and underground mine in northern Chile, and it demonstrates the impact of several variables on the resulting conditional simulation models. It also compares a more ?traditional? resource classification scheme applied, and the wide difference in local confidence intervals for each mining unit.

May 1, 2001

By H. Dundar, C. Dzomeku

An extensive testwork was performed around the HPGR plant at GoldFields Ghana Limited Tarkwa Gold Mine. The HPGR was used to prepare the feed for heap leaching. The circuit was configured in such a way that the edge material from the HPGR discharge was recycled for further crushing while the product from the centre reported to the heap leach section. The set-up of the Polysius HPGR provided an opportunity to study the effect of different design and operating variables. This paper will discuss the results from the tests performed to assess the effect of rolls’ speed and applied pressure on the capacity and the grinding efficiency of the HPGR. Applying different pressure values appeared to have an influence on the amount of edge material recycled.

Jan 1, 2012

By E. Goodwin

The mechanics of formation of wear-metal suspensions in lubricants is discussed, along with the relationship of the concentration of the metals and other particles to the wear of lubricated machinery parts. The importance of particle and suspension analysis of used lubricants in a preventative maintenance program is stressed, in particular with regard to mobile equipment in a mining operation.

Jan 1, 1978

By R. R. Montigny

A brief description is given of the history, location and geology of the Granisle Copper Limited operation on Copper I land in Babine Lake. Detailed information is given with regard to pit design, planning, drilling, blasting, excavation and haulage. Equipment maintenance and mining costs are also presented.

Jan 1, 1971

By W. J. Farley

"The Sherritt Gordon mine is 100 miles north of The Pas in northern Manitoba. Copper-zinc ore was discovered on the property in 1922. Production began in 1931 and continued to June, 1932, when operations were suspended because of the low price of copper. Operations were resumed on August 1st, 1937, and have been carried on continuously from that time to the present (March 1947). The production of metals up to the end of 1945 was copper, 287,129,880 lb.; zinc concentrate (50 per cent) 104,419 tons ; gold, 79,388 oz.; silver, 2,529,974 oz.GENERALThe ore occurs in two deposits, the east and the west. Both are enclosed in gneisses that are highly metamorphosed sedimentary and volcanic derivatives. The rock beneath the deposits, and hence forming their footwall, is gneissoid quartzite; the hanging-wall rock is basic garnetiferous hornblende gneiss. Pegmatite commonly occurs along both foot- and hangingwall peripheries and as isolated blocks and fragments within the ore zone . These blocks and fragments are considered to be residuals of unreplaced host rock .The ore is relatively coarse grained and ranges from the massive to the disseminated type. The metallic sulphides composing these, named in the order of their abundance, are pyrite and pyrrhotite ( 2-1 ratio) , chalcopyrite, sphalerite (marmatite) , and minor chalmeriite; subordinate amounts of gold and silver are recovered . The insoluble content of the ore averages about 35 per cent.Another deposit known as the Bob Lake, much smaller and lower in grade but having very similar relationships, occurs about 3 ½ miles to the northeast of the main Sherritt Gordon ore masses.STRUCTUREThe Sherritt Gordon orebodies are of the replacement type, and lie within a pegmatite sill that has been intruded along a contact between quartzite and hornblende gneiss. The two main orebodies are intimately related, for the east deposit is an erosional remnant of the lower, easterly limit of an orebody once continuous with the west body. The ore lies along the southwest limb of an overturned syncline."

Jan 1, 1954

By J. E. Armstrong

"Pinchi Lake and Bralorne Takla mercury mines; Canada's only producing mercury mines during the past war (1939-1945); occur within the Pinchi Lake mercury belt. This belt is in central British Columbia; and is approximately 150 miles long extending from southeast of Fort St. James northwest to the headwaters of Omineca river.During the field season of 1937 cinnabar was discovered by J. G. Gray of the Geological Survey in Permian limestone on the north shore of Pinchi lake, where the main showings of the Pinchi Lake mercury mine were later developed. Following the publication of Gray's report claims were staked in the spring of 1938, and later that year were optioned to the Consolidated Mining and Smelting Company, and in June 1940 a reduction plant with a rated capacity of SO tons a day was brought into operation. In 1943 the plant had a capacity of more than 1,000 tons a day. The grade of ore treated was reported to average S to 10 pounds of mercury a ton, and production during the years 1940 to 1944 exceeded 4,000,000 pounds. The Bralorne Takla mercury mine, which is 90 miles northwest of the Pinchi Lake mercury mine, was brought into production in November 1943 with completion of a 50-ton mill. During the next 10 months more than 100,000 pounds of mercury were recovered, and the grade of the ore was reported to average 15 to 20 pounds of mercury a ton. During the war, production from these two properties was far in excess of Canadian requirements, and Canada was able to supply the United Kingdom and United States with part of their need.s. Both properties ceased operations during 1944, and, due to an excessive supply of mercury, have not yet reopened. The Pinchi Lake mercury belt lies along a northwest-trending major fault zone called the Pinchi fault zone (Fig. 1). This zone is approximately 150 miles long and varies in width from 200 to 1,000 feet . It forms the northeastern edge of a northwest trending fault belt up to 10 miles or more wide in places. In general the northeastern margin of the Pinchi fault zone represents the contact between closely folded, stratified Permian rock:s on the southwest and Mesozoic formations and Omineca intrusions on the northeast. It seems probable that the fault zone marks the site of major thrust faulting from the southwest and that the Permian rocks moved up with respect to the Mesozoic formations. Intense faulting occurs in the Permian rocks within the fault zone. There the more important faults trend north and northwest, dip steeply west and southwest, and may join a major low-angle thrust fault at depth."

Jan 1, 1954

By A. van As, J. McGaughey, M. J. Mol, R. Tosen

Geotechnical monitoring is a key element of the successful management of a block cave mine. The interrelationships between production and various monitoring datasets are often not realized due to a lack of data integration and appropriate 3D visualization. Timely delivery of information to ensure best cave management practices is only possible with an integrated cave management system. At Rio Tinto, a state-of-the-art cave management system (CaveCAD) has been designed and developed in cooperation with Mira Geoscience to integrate and analyze vast datasets and report this as instructive information regarding the current \u201cstatus\u201d of the cave.

Jan 1, 2014

By Kamran Esmaieli

Open Pit Mining Through Underground Voids: Challenges Main Challenges/Hazards: Unexpected collapse of the pit floor and/or pit walls; The loss of equipment and/or people into underground voids; Loss of explosives from blast holes that broken through into the underground voids. How to address these challenges? An important step that must be integrated into mine planning and design is the accurate detection and delineation of underground voids. (i.e. probe drilling, Geophysical techniques, laser scanning,?); Leaving a pillar of adequate thickness between the working bench and the underground voids; Backfilling the underground voids from surface using vertical or inclined raises; Monitoring the working locations (pit floor and pit slopes) to detect movements.

May 1, 2013