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By J. Davis, M. G. Reading

"INTRODUCTIONInternational Minerals and Chemical Corporation (Canada) Limited operates two potash mine/refinery complexes near Esterhazy, Saskatchewan. Annual production of approximately 4.2 million tons is sold in the United States and overseas in five grades according to size and quality.Ore grading 25% K2 0 equivalent is mined from a horizontal bed by continuous boring machines, crushed, and hoisted at 8 inches. The refinery operation consists of the eight basic steps shown in Figure 1. Particle sizes handled are similar to those experienced in other forms of mineral beneficiation: 8 inches to 100 mesh. The ore is crystalline and particles are angular. Fortunately the major mineral constituents, sylvite (KCl) and halite (NaCl), demonstrate relatively low hardness at 2 to 2.5.Therefore, while simple abrasion must be acknowledged, it is not a major problem except, of course, in circuits carrying magnetite.Corrosion, as represented by the classic equations of Figure 2, occurs in all its various forms."

Jan 1, 1983

By C. F. Gleeson, D. G. Sheehan

"The results of humus and overburden geochemical surveys over the Doyon, Bousquet and Page-Williams gold ore deposits are presented.These studies show that humus sampling for gold gives negative results over the Doyon deposit. The lack of response is probably caused by the presence of 1 m of relatively impermeable glaciolacustrine clay and silt that overlies 1 m to 2 m of till over the surface expression of the ore zone. By contrast, positive responses for gold occur in humus samples over the Page Williams A and C gold deposits. The ""A"" ore zone is covered by several metres of exotic calcareous till over 0.5 m to 1 m of older, locally derived till. Anomalous values for gold in humus range from 10 to 35 ppb over the orebody. Overburden over the ""C"" ore zones is much thinner, generally it consists of less than 2 m of sandy till. Trenching humus anomalies that range from 10 to 1360ppb Au uncovered the gold mineralization. The geochemical dispersal trains in till from the Doyon orebody and the Page-Williams ""A"" zone are relatively short (i.e. less than 200 m) because both deposits occur in the lee of bedrock highs that shielded them from extensive glacial quarrying. Dispersal trains from all three pyritic gold deposits can be defined using either the fine fraction or heavy mineral fraction of the till.The intensity of the gold in till anomalies over the ore zones is variable. Therefore, it would be misleading to attach rigid significant threshold gold values to overburden drilling results. Each case must be evaluated based on bedrock topography, sample density, overburden type, thickness of till, as well as size, type and orientation of the target exposed to glacial erosion."

Jan 1, 1987

By Mohan R. Srivastava

- OUTLINE - apologies and explanations - a quick bit of history - the wisdom of Wikipedia - ?Matheronian geostatistics continued to convert Bre-X?s bogus grades and Busang?s barren rock into a massive phantom gold resource?? - variogram analysis for Busang - would variogram analysis (or variance analysis) have revealed the fraud? - what went right, what went wrong

May 1, 2007

"Batch flotation testwork demonstrated that a low-grade chromite ore from Bird River, Manitoba, was best floated at pH 2 using Armac C (coco amine acetate) collector and sulphuric acid as pH modifier. A grind of 100% minus 150 um was necessary for liberation, and flotation selectivity was greatly enhanced by prior desliming. A concentrate analyzing 24.2% Cr203 with a recovery of 90.2% was obtained, after three cleaning stages, from ore grading 6.05% Cr203. Total rougher collector concentration was 500 g/t and cleaner collector concentration 380 g/t. Similar grade and recovery were obtained during the pitot-plant evalualion, when a concentrate analy zing 22.3% Cr203 with a recovery of 93% (based on deslimed feed) was obtained for a total collector addition of 630 g/t.Selective flotation in a region of positive surf ace charge implies anionic activation, and a possible flotation mechanism is suggested.IntroductionIn an earlier study(1) of the beneficiation of chromite ore from Bird River, Manitoba, several methods of beneficiation were explored. These included ore sorting, heavy-media separation, and gravity concentration with flotation using Armac C (coco amine acetate) collector at pH 2, and sulphuric acid as pH modifier. Because flotation was not fully evaluated, a laboratory study was undertaken to determine the optimum parameters of chromite flotation. Optimization of parameters was established first on a laboratory scale followed by confirmation a t the pilot -plant level. Flotation of chromite using Armac C and sulphuric acid as a pH modifier has been reported as being selective for low-grade chromite ores(2)."

Jan 1, 1990

By M. Dotto, T. G. Joseph, M. Curley

"Equipment selection is a key decision in mine planning. Equipment size affects decisions from pit size to the total operation cost. Particularly when replacing haulage fleets for long-life surface mining operations, mining operations focus solely on haulage productivity. Road width and specifically ramp width are significantly affected by an increase in hauler size in terms of overall strip ratio through required highwall set-backs or sterilizing of lower ore access due to required overlying ramp fill structures. In addition, in light of ever increasing regulatory and reporting emissions requirements, bigger equipment may not translate into lower emissions per tonne moved. This study analyzes hauler-scale impacts on aspects not currently incorporated into conventional mine planning, including expansion of roads to accommodate larger equipment, road layer thickness variation depending on hauler size, and fuel consumption and emissions. Results indicate that such relationships have a large impact on cost. Therefore, an expanded consideration of the capacities of increasing equipment size in mine planning is highly recommended. ¦ KEYWORDS Equipment selection, Grade resistance (GR), Haul road, Haul truck, Mine planning, Payload, Rolling resistance (RR), Total resistance (TR) RÉSUMÉ La sélection du matériel est une décision importante dans l’aménagement des mines. La taille de l’équipement a une incidence sur la prise de décisions, depuis la taille de la fosse jusqu’aux coûts totaux des activités. L’exploitation minière se concentre uniquement sur la productivité des moyens de transport, particulièrement lorsqu’il s’agit de remplacer les parcs de camions de transport dans les exploitations à ciel ouvert à longue durée de vie. La largeur des routes, et spécifiquement la largeur des descenderies sont considérablement affectées par une augmentation de la taille des camions de transport en termes du coefficient global de recouvrement qui dépend de la taille requise des parois (si les descenderies sont agrandies, les parois devront être creusées de haut en bas afin d’agrandir la taille du fond de la fosse). Il faut aussi pouvoir procéder à l’excavation des gradins les plus profonds de la mine et ainsi préserver l’accès à cette zone, ce qui pourrait devenir difficile si la quantité de stériles utilisés pour la structure des descenderies augmente et s’ils occupent une trop grande partie du fond de la fosse. En outre, au vu des exigences de plus en plus strictes en matière de réglementation et de déclaration des émissions, un équipement plus volumineux ne sera pas nécessairement synonyme d’une réduction des émissions par tonne déplacée. Cette étude analyse l’incidence de la taille des camions de transport sur des aspects actuellement non intégrés dans l’aménagement classique des mines, notamment la création de routes permettant le passage d’un équipement plus volumineux, la variation de l’épaisseur de la couche d’asphalte des routes en fonction de la taille des camions de transport, ainsi que la consommation de carburant et les émissions. Les résultats indiquent que ces relations ont des répercussions importantes sur les coûts. Ainsi, on recommande d’accorder une attention accrue aux capacités d’augmentation de la taille de l’équipement dans l’aménagement des mines. ¦ MOTS CLÉS aménagement des mines, camion de transport, charge utile, résistance au roulement, résistance due aux rampes, résistance totale, route de transport, sélection du materielINTRODUCTION Over the past five decades, the mining industry has progressively attempted to increase production rates through the use of larger haulage equipment. Each new generation of mine is designed to operate with the most recent and often bigger equipment iteration, while older mines are re-evaluated to keep pace with upgraded mixed fleets. Whereas production gains are often realized with larger equipment, there are additional aspects to consider when evaluating the feasibility of mo"

Jan 1, 2019

By M. R. Saharan

A brief overview of rockburst control measures is presented. The paper then elaborates on one key rockburst control measure, which is known as destress blasting. A historical background of the technique is presented in order to understand different aspects of its field application. The publication enumerates key aspects of the technique as being used in practice in South Africa and North America. The paper also presents an analysis of three case studies in order to demonstrate difficulties associated with the field application of distress blasting in hard rock mines.

Jan 1, 2006

By G. W. Poling

"Construction, equipping and planned operation of a new laboratory for engineering-teaching and research in coal and mineral processing is described. This facility will provide approximately 1860 m2 (20,000 ft. 2 ) of laboratory space with nearly half devoted to a new venture in coal preparation. Two high-bay, overhead crane-accessed areas will accommodate major unit operations for each of the ""coal"" and ""mineral"" laboratories. COAL PREPARATION FACILITIES:The coal facility provides three main functional areas:(1) Sample preparation (drying, blending, crushing, screening) and sink-float washability testing.(2) Unit operations U1igh-bay, serviced by crane).(3) Analytical laboratories.(l) Sample Preparation and Sink-Float TestingBreaking or comminution of coal will be accomplished using a rolls crusher, a hammer mill, a jaw crusher, or a pulverizer. Capacity to prepare coal at rates of up to approximately 4 tph will be provided by some of these units. Large diameter (~0.5m) baths of heavy organic liquids will be available for sink-float washability tests on coal samples of several kg. Particle sizes of up to 25 mm can be tested in these baths. Smaller scale washability tests on finer samples will be accelerated by centrifuges."

Jan 1, 1980

By A. J. Rigby

Computer generated, actual-scale furnace models have been imported into a rendering software application to provide for impressively realistic surface features and lighting. When these models are imported into a 3D engine framework, it is possible to create content-rich virtual environments allowing for complete interactivity and could provide for a powerful tool to conceptualize refractory lining designs. This technology has been applied to illustrate the optimized design concept of an anode-refining vessel, which can be expected to be completely relined in six days and to last for 4-5 years with minimal partial relining. This technology could easily be applied to other smelter furnace, converter and refining vessel designs.

Jan 1, 2007

NANA Accepts Mining ­ 1974 - Leadership presented mining option to people ­ Community meetings; recognized need for cash economy ­ 1979 - Poll shows consensus in favor of mine development ­ 1980 - Shareholders approve mining; Congress approved land selections

May 1, 2002

By Erik Richer La Fleche

LEGAL RISKS LEGAL RISKS ARE COUNTRY RATHER THAN PROJECT RISKS OTHER COUNTRY RISKS ARE POLITICAL AND MACRO-ECONOMIC RISKS COUNTRY RISKS ARE EXAMINED AFTER PROJECT RISKS COUNTRY RISKS COUNTRY RISKS INCLUDE: WAR AND ARMED CONFLICT TERRORISM AND SABOTAGE CURRENCY INCONVERTIBILTY AND TRANSFER NATIONALIZATION AND CREEPING EXPROPRIATION GOVERNMENTAL BREACH AND REPUDIATION OF CONTRACT CHANGE OF GOVERNMENT CORRUPTION COUNTRY RISKS FIRST NATIONS AND LANDOWNER CLAIMS LABOUR UNREST SINGLE CAUSE ACTIVISTS REGULATORY AND BUREAUCRATIC DELAYS CONFLICT BETWEEN GOVERNMENT LEVELS ETHIC AND RELIGIOUS TENSIONS INTERNATIONAL SANCTIONS TAXATION CHANGES CHANGES IN LAW

May 1, 2013

By Weldon Li

Outline ?Introduction and Motivation ?Previous Research ?Details ?Findings ?Current Multi-Piece Mining Wheel Research ?Methodology ?Preliminary findings ?Current and Future Activities ?Summary and Closing Remarks

Oct 1, 2010

By Paul Graham

Presentation Focus ? What is LTUG / What do we do? ? History of LTUG ? Examples of Benefits from LTUG Participation ? Encourage Participation What is LTUG? ? An informal gathering of surface mining companies to discuss and work issues of common interest and to share information and best practices around large tires.

May 1, 2008

By Bétournay. M. C.

Advantages ?Safety ?Health ?Rapid, continuous development, productivity ?Stope dilution reduction Disadvantages ?High cost and long time for equipment development ?Hard rock mining condition limitations ?Size of equipment ?Equipment set-up time, down time ?Performance does not meet financial return targets ?Drill and blast retains advantage in cost, productivity, capital investment, application flexibility ?Stress accumulation issues in deep mining, ground support and material handling issues in weaker rock

May 1, 2009

By Tom Dettweiler

Who We Are A global pioneer in discovery, development and recovery of deep-ocean assets Shipwrecks Deep-sea Minerals Company Overview Founded 1994 HQ ?Tampa, Florida USA Employees 45 Tampa + 150 Abroad Publicly Traded: NASDAQ:OMEX Requires Specific Financial Controls and Reporting

May 1, 2013

By Brad Ross

? Value in number of children ? Polygamy common ? Support of extended family and friends ? HIV/AIDS ? Not a culture of savings ? Minimal mechanical experience ? Supportive ? Unintended hindrance ? Mining claims ? Export Permits Lack of funding

May 1, 2011

By Richard Howie

Avian Diversity ?? Pre-mining ?? 110 - 125 species would have occurred ?? Dominated by forest species ?? Wetland productivity unknown ?? Post mining ?? 192 documented ?? Forested species in reduced numbers ?? Increase in wetland species ?? Increase in open country/grassland species

May 1, 2008

By Emilio Giuseppe Sarno Severi

Mining and Petroleum Similar Industries ?Asset Intensive ?Exposed to market volatility ?Highly Risky Operations ?Scarcity of Experienced and Trained resources ?Operating in diverse countries with different cultures ?Increasing Environmental and Safety Regulations

Nov 1, 2011

By T. Hidayat

The distributions of minor elements between slag/metal and slag/matte in equilibrium with tridymite in the Cu-Fe-O-S-Si-Al-Ca system have been investigated in the range of conditions of interest to the high- temperature copper production, refining, and recycling processes. An improved experimental methodology has been used involving high temperature equilibration in controlled gas atmospheres, rapid quenching, and quantitative microanalysis techniques using Electron Probe X-ray Microanalysis (EPMA) and Laser Ablation Inductively Coupled Plasma Mass Spectrum (LAICPMS). The effect of oxygen partial pressure on the distributions of minor elements between slag/metal and slag/matte has been accurately measured. The effects of slagging components (Al2O3 and CaO) on the distributions of minor elements between slag/metal have also been experimentally determined. The present study is a part of a larger integrated experimental and thermodynamic modelling research program in the systems relevant to high-temperature copper processing. INTRODUCTION In the high temperature processing of copper, minor elements are distributed between different phases, i.e. liquid slag, liquid matte, and liquid metal. From a processing perspective, it is desired to have the valuable minor elements distribute predominantly in the metal and matte phases rather than in the slag phase, and to have the non-valuable minor elements distribute predominantly in the slag phase rather than in the metal and matte phases. Knowledge of the distributions of minor elements between phases in the smelting, converting, and refining processes is required if the distributions of minor elements between phases in these processes are to be optimized.

Jan 1, 2019

By Richard Peaker, Jens Lichter, Alexander V. Potapov

"The recent combination of Computational Fluid Dynamics (CFD) and Discrete Element Modeling (DEM) can provide considerable insight into the performance of flotation cells. One area of interest from a fundamental equipment design perspective has been the influence of flotation cell size and the inflow rate on the metallurgical performance of the cell. One of the specific design objectives when increasing the size of flotation cells, or increasing the feed flow to the flotation cell, is to ensure that the feed stream flowing into the cell does not have an opportunity to bypass the mechanism.This paper describes the initial modeling efforts to quantify the inter-relationship of cell size, inflow rates, and feed and discharge box placement, on the retention time distribution of solids in the flotation cell, and the fraction of particles that bypass the mechanism on a size by size basis.INTRODUCTIONThe great majority of newly installed cells in mineral processing plants world-wide are of the cylindrical tank design and this tank shape offers a number of hydraulic advantages over the older style of square cells. Cylindrical cells give symmetrical flow patterns and by careful design of the mechanism and tank internals, the flow patterns generated can concentrate the more intense mixing in the lower portion of the cell to promote good solids suspension and particlebubble contact. Simultaneously, cylindrical tank design gives a more quiescent upper zone for particle-bubble transport into the froth zone. These symmetrical flow patterns are naturally disturbed in normal operation by the slurry inflow and outflow from the individual cells. The challenge for flotation cell designers is to determine the magnitude of these flow disturbances, and to assess whether or when the inflow and outflow rates have a sufficient impact on the hydraulic flow patterns so as to potentially affect the metallurgical performance of the flotation cell."

Jan 1, 2007

By Xuanxue Mo, Kaihui Yang, Steven D. Scott

Abstract -The Changning-Menglian metallogenic belt in western Yunnan, China, is characterized by the occurrences of both Pb-Zn-Cu and Cu massive sulfides in Permo-Carboniferous mafic volcanic sequences. These deposits were formed in a back-arc basin at a rifted continental margin in the Paleozoic Tethys Ocean. Pb-Zn-Cu deposits are associated with alkalic basalt, andesite, and lesser felsic volcanic rocks intercalated with limestone, which probably formed along an immature rifting segment on a continental basement. These volcanic rocks are enriched in K, Ti, LREE, and other incompatible elements, and have the attributes of alkalic within-plate basalt. An extensive unit of sulfide- carbonate-silica shale in proximity to massive sulfides contains high values of Mn, As, Mo, W, Sn, Sb, and Hg, and has REE patterns that are similar to the volcanic rocks. This, together with the graded bedding in the footwall volcanic rocks, suggests that the sulfides precipitated in a shallow, unstable, and carbonate-saturated volcanic basin. A stringer zone is traced downward for 500 m below the massive sulfide orebodies. It is characterized by an upper sericite-quartz zone and an extensive lower skarn alteration with enhanced W, Sn, and Bi. Lead isotope data show both continental basement and magmatic sources may have supplied the ore metals. Cu deposit and occurrences are hosted by tholeiitic units that represent the mature spreading segments in the back-arc basin. The tholeiitic lavas have LREE-depleted or flat REE patterns similar to MORB or back-arc mafic lavas. The cupriferous massive sulfides are overlain by an extensive unit of chlorite-magnetite or ochre, suggesting a relatively oxygenated oceanic basin. Ni and less Co mineralization is found in dolomite veins of the stringer zone. Enhanced concentrations of Ni, Co, Au, and As are found in the massive sulfides and in sulfide-rich tuffites. The geological setting and mineralization of the Changning-Menglian belt has similarities with modern back-arc basins such as the Manus Basin in the western Pacific.

Jan 1, 1999