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By M. H. Colebrook

Nickel laterites contain about 70% of all continental or terrestrial nickel resources; therefore the recovery of nickel from lateritic ores has large economic significance. The processing of lateritic ores involves the preparation and movement of concentrated aqueous suspensions. However due to complex characteristics and non-Newtonian properties, ranging from shear-thinning to shear-thickening and from thixotropic to rheopectic, a basic understanding of the flow behaviour must be developed. This understanding will assist in the development of new plants and the operation of existing plants. The work in this paper involves the characterization of three ore types from the Vermelho ore deposit to categorize them as rheologically simple to complex. Rheological testing was also conducted on pure mineral samples that represent the main minerals in these samples. The results show that the rheological properties of the ore types can be related to the surface properties and physical characteristics of the main mineral constituents.

Jan 1, 2006

By M. B. Greyver

The results of laboratory tests on iron precipitation from non-decopperized nickel anolyte are discussed. The parameters (pH, oxygen consumption and stirring speed) for iron precipitation from the anolyte, using the oxygen in the air, were determined. In the experiments conducted under optimized conditions, the residual concentration of iron in the anolyte after precipitation was 0.7-2.7 mg/L, and the copper and nickel losses to the solid phase were 0.05-0.07% and 0.05-0.16%, respectively. The filtration ability of the iron slurry obtained was 2 to 5 times higher as compared to that after chlorine oxidation and oxyhydrolysis. The leaching of the non-ferrous metals from the iron cake made using the separate nickel anolyte purification process was possible by dissolution in sulphuric acid. It was established that after cobalt precipitation from the copper- and iron-depleted anolyte, the precipitates obtained had lower ratios of Fe:Co and Ni:Co.

Jan 1, 2006

By Oscar F. Tangel

This paper outlines Canada's current status in world iron ore markets, and evaluates t he prospects for the future. Estimates for the production, export and consumption of iron ore are given. Canada's major market will continue to be the United States, with the European Common Market countries, Japan and the United Kingdom also forming important outlets. The advantages held by Canada's major competitors in these latter three market areas are briefly discussed

Feb 1, 1966

By Oscar F. Tangel

This paper outlines Canada's current status in world iron ore markets, and evaluates the prospects for the future. Estimates for the production, export and consumption of iron ore are given. Canada's major market will continue to be the United States, with the European Common Market countries, Japan and the United Kingdom also forming important outlets. The advantages held by Canada's major competitors in these latter three market areas are briefly discussed.

Jan 1, 1966

Presentation Agenda ?Background ?OEM Recommendations before RCM ?Operating Context ?OEM Recommendations after RCM ?Reality of Failure ?RCM Deliverables ?Maintenance program optimization ?Spare part optimization ?Implementation ?Further Considerations -Three scenarios ?Summary and Conclusion Background ?P&H Mining?s LCM division performed a RCM study on a ?generic 4100 XPB shovel?in Milwaukee. ?P&H soon realized that the analysis required context -The recommendations were manufacturer knowledge based. -The outcome based on manufacturer requirements. -The strategy was not applicable to all machines, etc. Operator experience and ?local knowledge? are key to the success of an RCM analysis. P&H approached Teck Coal?s Fording River Operation to assist with ?Operating Context?. Teck provided operator and maintainer experience.

May 1, 2010

By Apoorva Bajaj

Iron ore mines of Steel Authority of India Limited (SAIL) have to comply with strict chemical composition norms laid down for iron ore lumps supplied to its steel plants. This requires a careful planning of the overall ore excavation operation. In general terms, the problem can be stated as: Given the chemical composition of ore for all excavation sites, excavation capacity of each shovel, distance of each excavation site from the crushing plant and the number of dumpers available for transport of the ore, find out the percentage of ore to be excavated from each excavation site such that the production rate is maximized and the chemical composition norm is satisfied to the best possible extent. This paper presents an approach to solve this problem using Branch and Bound method. The specification for r.o.m. quality has been modified by incorporating a new parameter, ?Al2O3 / SiO2? ratio, which has a significant effect on the performance of iron blast furnace.

Oct 1, 2009

By Felix D. Klebe

Efficient, high volume, mine load out operations have evolved in recent years to include more sophisticated control systems that integrate with mission critical equipment such as weighing systems. Traditional weighing systems often involve static weighment of individual railcars and either manual or serial transmission of scale data to a database application. In recent years integration of railcar or truck weight data into a loadout operation via direct PLC or Ethernet communication between the weighing terminal and the loadout control system has been realized. Furthermore, use of dynamic railcar weighing where railcars are automatically weighed while moving has increased productivity in a variety of mining applications.

May 1, 2008

By D. A. Bordin, C. J. Newman, R. J. St. Eloi

"The requirements for a metallurgical acid plant treating smelter gases are both unique and demanding in terms of sulphur dioxide treatment and emission control. Since start up in 1981, the copper smelter at the Kidd Creek Division of Falconbridge Limited has undergone several major expansions. The expansion and modification of the acid plant has been an integral part of this process. Both production demands and government regulations dictate that this metallurgical acid plant be unique in terms of operating flexibility. The variable capacity to treat a wide range of sulphur dioxide concentrations, and the operating flexibility to control emissions are the topics of this paper.INTRODUCTIONThe Kidd Creek Division of Falconbridge Limitied is a base metal mining and metallurgical complex located in Timmins, Ontario. The discovery of the original copper-zinc-silver orebody was announced in April, 1964. Mining operations began in 1966 with a 9000 tonne per day concentrator coming on stream in November of that year. In April 1972, a 108 000 tonne per year zinc plant was commissioned. Over the years the facilities have been expanded, such that the concentrator now has the capacity to process 13 000 tonnes of ore per day . To expand zinc production, the world's second installation of the Cominco/Sherritt pressure leaching facility was completed in 1983 to bring total zinc production capacity to 125 000 tonnes per year. In 1973, serious planning for a smelter operation began. In early 1975, after studying both continuous smelting and flash smelting processes, a decision was made to proceed with the technology offered by Mitsubishi Metal Corporation of Japan. The Mitsubishi Continuous Smelting Process was to be used for the smelter and the Onahama No.3 tankhouse technology for the copper refinery.The smelter, which uses the Mitsubishi Continuous Smelting Process for the continuous production of blister copper from concentrate, went on line in June 1981. It has been expanded from its original capacity of 60 000 tonnes to 100 000 tonnes per year of copper.From the very early design stages for the metallurgical complex, the company had adopted a policy of constructing and operating modern plants which would meet existing and anticipated environmental standards. With this in mind, the decision was made to utilize the proven technology of fixing sulphur dioxide emissions, in the form of sulphuric acid. A 636 tonne per day single absorption contact acid plant was built to serve the zinc plant in 1972. In 1981, an 883 tonne per day double absorption contact plant was built to serve the needs of the copper smelter. The copper smelter acid plant has since been expanded to a design capacity of 1692 tonnes per day and it is the main focus of this paper."

Jan 1, 1989

This paper generalizes open stopes into elliptical cross sections and applies the results of calculations based on the mathematical theory of elasticity to indicate stress distribution on the boundaries of such stopes. These show both compressive and tensile stresses and provide an ex-planation for the development of excessive dilution in shrinkage toping. Introduction T HE stress pattern around shrinkage stopes is identical with that around other stopes under the same physical conditions. However, a shrinkage stope ends as an unsupported open stope, and the method i limited to the stress range within which the rock is generally self-supporting. If it is acceptable to generalize the outline of a shrinkage stope into an elliptical cross section, then the graphs of Geldart & Udd (1) (see also Panek (2) and Denkhaus (3)) provide a good base for approximating the stress distribution as mining progresses. However, with failure conditions in the walls, the axis ratio, as cut

Jan 1, 1964

Spatial information Critical to a project since it underpins: ?Discovery of mineral resources ?Orebodydefinition and technical assessment ?Mine design and planning ?Profitability and project value Data ?Single most import asset. ?Good interpretation of quality data underpins project growth and success. TEAMWORK

May 1, 2002

By W. C. Zhu, C. H. Wei, L. L. Niu

With an increase of mining depth, a series of mining-induced hazards such as rockburst, coal and gas outburst, roof collapse, and water burst are getting more serious and more frequent. The intrinsic mechanism responsible for the occurrence of mining-induced hazards is the damage and unstable failure of rockmass or coal seam. The most distinct difference between deep and shallow levels is the so-called three ‘high’ (H3) conditions, i.e. high geo-stress, high fluid pressure and high geo-temperature. Therefore, the response of rock or coal to the deep mining operation is a phenomenon involving thermal (T), hydraulic (H), and mechanical (M) processes. Most importantly, mining excavation may vary the rock stress condition greatly, which may be a key factor to trigger the mining-induced hazards such as rockburst. In this regard, it is of great significance to clarify the damage and failure mechanism of rock and coal under coupled THM conditions, in order to clarify the rock failure mechanism responsible for the occurrence of mining-induced hazards. Thereafter, the mining-induced hazards cannot be predicted with confidence by considering each process independently. Of course, the requirement to include coupling of these processes depends on the specifics of the mining-induced hazards under consideration. For example, the water inrush is considered as a coupled hydro-mechanical (HM) process, in which the unstable failure of rockmass occurs under the combined contribution of geo-stress and water pressure. As for the coal mining at depth, in addition to high geo-stress and gas pressure in coal seam, the high geo-thermal condition that may greatly change the adsorption / desorption of gas and gas flow should be taken into account. Firstly, a general-purpose mathematical model for rock damage and failure process under coupled THM conditions is formulated based on damage mechanics principle, and it is solved by finite element method (FEM). In this model, the deformation and damage of rock, fluid flow and thermal transfer in rock would interact with each other, one process affects and initiation and progress of another. Then, the model is used to predict the mining-induced water outburst, where it is simulated as coupled hydro-mechanical (HM) problems. Based on the numerical simulation, the dimension of water-proof pillar is designed. Finally, the gas drainage from deep coal seam is numerically evaluated, where the coupled coal-gas interaction considering the effect of gas adsorption/desorption, gas flow in coal seam and geo-stress and geotemperature, is comprehensively taken into account. The proposed model could be used for clarifying the mechanism of mining-induced hazards in deep-level mining.

Jan 1, 2015

By F. Qi, T. Frišcic, C. Mottillo

"One of the principal goals of modern industry is to minimize the environmental impact and increase the materials- and energy-efficiency of transforming raw materials into valuable products. This paper will highlight our latest laboratory-scale research in low-energy, low-solvent reactivity of metal oxides and their conversion into popular metal-organic frameworks (MOFs), zeolitic imidazolate frameworks (e.g. Basolite® Z1200 component ZIF-8), and metallodrugs (e.g. bismuth subsalicylate, active component of Pepto-Bismol®). Mechanochemical ion- and liquid-assisted grinding (ILAG) and ""accelerated aging"" techniques will be presented, along with novel low-energy and solvent-free approaches, inspired by geological weathering processes, for converting metal oxides into metal-organic materials. INTRODUCTIONThe development of environmentally-friendly processes, which would in the same time be more materials- and energy-efficient than the existing ones, is one of the central concerns of modern chemical research. In that sense, the focus of the chemist has been mainly on the preparation of carbon-based organic molecules and adaptation of traditional organic synthesis to the recently delineated ideals of Green Chemistry. However, there is a growing realization within the chemistry community that significant energy, materials, and ecology-related benefits can be achieved and, indeed, targeted in the transformations of materials that are typically associated with inorganic chemistry and minerals processing. The principal aim of this highlight contribution is to illustrate how, through the use of approaches associated with solventfree chemistry and mechanochemistry (James et al., 2012), one can develop a clean and efficient system of chemical and materials transformations involving oxide precursors that normally belong to the realm of inorganic chemistry and mineral processing. In particular, this contribution will provide an overview of the recently developed mechanochemical and solvent-free reactivity of metal oxides towards small organic molecules. These mechanochemical reactions, including the methods of liquid-assisted grinding (LAG, Frišcic & Jones, 2009) and ion- and liquid-assisted grinding (ILAG, Frišcic, 2010), have so far provided a radically different means to construct advanced metal-organic materials (e.g. porous metal-organic frameworks, [MOFs] or metallodrugs) by rehabilitating metal oxides as precursors, eliminating the use of bulk organic solvents, and avoiding the use of high temperatures."

Jan 1, 2012

By Art Hamilton

The Zn-Pb-Cu-Ag ore deposits of the Boundary and N-5 zones near Bathurst, New Brunswick, occur in a polydeforrned volcano-sedimentary sequence that is part of the Ordovician Tetagouche Group. Massive and disseminated sulfides are hosted by an argillaceous to cherty sedimentary sequence that is stratigraphically Wlderlain by a siliceous fragmental unit and is overlain by a feldspar-rich crystal tuff and related tuffaceous rocks. The deposits have a low iron sulfide content relative to that of most stratabound sulfide deposits of the Bathurst-Newcastle mining district. The ore is commonly associated with chlorite- and talc-rich sediments. The N-5 deposit is considered to be the fault-displaced extension of the Boundary deposit. The Boundary deposit is estimated to contain 891 000 t grading 3.31% Pb, 7.96% Zn, 0.32% Cu and 44 g/t Ag; the estimate for the N-5 zone is 330 000 t grading 3.24% Pb, 7.15% Zn, 0.33% Cu, and 37 g/t Ag. The ore is processed at 1000 tpd at the Heath Steele mill.

Jan 1, 1992

By Jonathan Matthews

Efficient and effective management of mine tailings is essential for continued successful development of Alberta?s vast oil sands resources. Syncrude Canada Ltd. continues to research novel tailings management techniques in an effort to improve production efficiency and environmental sustainability. During the summer months of 2001, Syncrude Canada Ltd., in collaboration with members of the Canadian Oil Sands Network for Research and Development (CONRAD), conducted field-scale trials of thickened tailings technology at Syncrude?s Aurora mine, north of Fort McMurray, Alberta. This paper provides an overview of the test program including discussion of objectives, test configuration, and program observations. 0Data collected during the field trial indicate that substantial swings in feed slurry composition challenge effective thickener operation. When coarse mineral solids dominated slurry composition, thickener rake torque rose to unmanageable levels. It was determined that the end-of-pipe depositional characteristics of thickened oil sands slurry were generally consistent with present understanding of oil sands tailings slurries. After shear, thickener underflow product exhibited very shallow beach angles and a limited capacity to keep coarser particles in suspension indicating that stacking of ?paste-like? thickener underflow product from a conventional thickener is not practical in an oil sands setting unless process adjustments can be made to increase the underflow density and/or preserve the initial high yield stress of the underflow during transport and deposition. These technical challenges notwithstanding, Thickened Tailings technology offers considerable promise for recovery of warm water from oil sands process tailings.

May 1, 2003

By S. K. Sharma, Sanket Bacchuwar, Prabal Kumar Agrwal, G. V. Rao

"Iron ore processing industries play a vital role in the Indian economy. At present Iron ore of around +64% Fe is used for production of Iron through blast furnace. To produce +64% Fe from low/medium grade ores, crushing & beneficiation is compulsory. But during these processes, large amount of slime is generated. It is estimated that 18% -25% of tailing is generated during the processing of iron ore. The iron ore slime is discarded because of its particle size and chemical composition not being suitable as feed to the blast furnace. Although the fines/slimes can be agglomerated to larger particle, the alumina to silica ratio which is normally more than one pose serious problem during sintering process and subsequent smelting in blast furnace. The alumina content in the slime needs to be reduced for it to be used as the feed for blast furnace. The sample assayed 61.40% Fe, 7.68% SiO2, and 1.52% Al2O3, LOI 2.63% and all other elements were found in critical limit. A series of 27 tests were conducted by using a spiral for optimisation of process parameters to produce a pellet grade concentrate from the stacked slimes obtained from Kirandul. This paper deals with the optimisation studies of various parameters of a spiral concentrator and helps to utilize the fines from tailing ponds.INTRODUCTIONReserves of high-grade iron ores are diminishing all over the world at an alarming rate. As a result, alternative ways of augmenting and conserving precious and non - renewable natural resources are being seriously considered. One such attractive option is the recovery of metal values from slimes / tailings. Iron ore tailings containing around 48 - 60% Fe are generated from the iron ore washing plants and are disposed into tailing ponds without any further utility. These tailings in the form of slimes are not suitable in iron and steel making due to the presence of higher amount of gangue constituents. Several beneficiation techniques have been tried from time to time to reduce the gangue so that the beneficiated products could be effectively used."

Jan 1, 2016

By H. Gharahbagheri, S. Shafiei Zadeh, H. Hassan Nejad, Reza Roostaazad

In this paper, dissolution of vanadium from mining residue, in which vanadium is associated intimately with magnetite ore, was investigated via both bacterial ( aerobic and anaerobic) and fungal activity. Although bacterial activity was tangible, it could not reduce and dissolve vanadium in both aerobic and anaerobic experiments. However, in fungal leaching, after 30 days about 36.9% and 29.7% of vanadium was dissolved for a pulp density of 10 and 30 g/l, respectively. At the end, the concentration of metabolites usually produced by fungal activity was optimized and oxalic acid was chosen as the main agent for the leaching process.

Jan 1, 2014

By E. J. Schwarz, A. A. Winir

"Absolute magnetite contents were determined for asbestos specimens in various stages of milling by using a Faraday-type thermomagnetic balance. Comparison of these results with magnetic ratings (MR) supplied by the mining companies cooperating in this study reveals strong scatter. The main cause of this scatter is thought to be that the MR values were obtained in magnetic fields well below the saturating field of magnetite (5,000 oe). However, only the saturation moment is an intrinsic property and consequently must be used for the purpose of obtaining reliable estimates of the magnetite content. Curie points indicate that virtually pure magnetite and possibly Ni3Fe is present in all samples, and another phase, probably (Cr, Al) magnetite, is present in a few samples. The susceptibility in fields stronger than 5,000 oe is positive and falls in the normal paramagnetic range, whereas sy nthetic chrysotile exhibits weak diamagnetism. This suggests that, as a general rule, the least adulterated natural chrysotile concurs with the samples showing the smallest positive susceptibility above 5,000 oe. The magnetite appears to increase in quantity with a decrease in fibre length and to be somewhat more uniform in distribution for samples showing substantial fiberization (opening of the fibres)."

Jan 1, 1971

By Alan L. Sangster

Auriferous, bedding-parallel veins occur in zones of carbonaceous, argillaceous and sulfidic turbidites in the Lower to Middle Cambrian sandy flysch of the Goldenville Formation. The 0348 values for vein and wall-rock arsenopyrite and pyrrhotite, and for regional pyrite and pyrrhotite, are highly positive. The values are similar to those from Cambro-Ordovician sediment-hosted deposits of other types, and display trends that increase upward in the stratigraphic sequence. The similarity in composition of vein and wallrock sulfides indicates a seawater-sulfate sourCe for sulfur, derived from the enclosing rocks at the time of vein formation. The upward increase in ?34S values is consistent with closed system sulfate reduction in the anoxic portion of a stratified water-colurnn. Published ? 13C and ? 18() values for Meguma Group vein carbonates are unlike those of other gold-vein carbonates, but are similar to those of diagenetic-metamorphic carbonates from the Meguma Group and elsewhere. These data indicate that the source for the vein-related sulfides and carbonates may be the host strata; possibly the arsenic and gold were derived from the same source.

Jan 1, 1992

By Dennis L. Murr, James E. Wennen

"The through-put and energy efficiency of an autogenous (AG) grinding mill are adversely affected by variability in rock size and rock competency. This applies to both fully autogenous and semi-autogenous (SAG) grinding circuits. In this paper we focus on an approach to overcome the problem of inconsistent mill through-put related to variability in mill feed size and rock competency. The focus is on ores containing hard, competent rock. This approach consists of preparing feed to an autogenous mill that contains 20% coarse media rock and 80% of material crushed to pass 37 mm. Results of pilot-scale testing for two iron-ores will be presented to show that a 10% to 12% reduction in unit energy consumption is possible with prepared feed, compared with feeding the mill with conventional primary crusher discharge.INTRODUCTIONIn the past 30 years or so, autogenous grinding and semi-autogenous grinding have been the comminution technologies of choice for most mining and mineral processing operations. These technologies saved both capital and operating expenses associated with the installation and operation of multi-stage crushing and screening plants required for conventional rod mill – ball mill circuits. However, SAG and AG are inherently inefficient in terms of energy consumption, especially for very hard ores. In cases of hard ore, changing characteristics of rock fed to the mills causes wide fluctuations in mill capacity, which contributes to the inefficiency. Rising electric power costs make this the most expensive unit operation used in the extraction of valuable minerals from an ore. The objective of the concept discussed here is to reduce the energy consumption in AG grinding for hard ore and eliminate the use of large-diameter steel grinding balls that are required for SAG grinding"

Jan 1, 2012

By J. A. R. Faucher

"Autogenous grinding may be an efficient and economical solution to your ore comminution problem.An important potential economic advantage of autogenous mills results from the availability of very large capacity units.Autogenous grinding could be more economical in terms of both capital and operating costs.Satisfactory pilot plant testing and thorough economic evaluation are required for a sound decision in comminution plant selection.INTRODUCTIONMankind's first weapon was probably the wooden club, but men soon learned to shape, smooth and polish stone for tools and weapons by pounding and rubbing them with sand and water. It was only about four thousand years ago that rocks were first broken to concentrate, smelt and return the metals they contained. In spite of our recent great technological advances we still break rock in essentially the same manner that was used thousands of years ago - by pounding, rubbing and squeezing - and we still waste much energy and metal in the process"

Jan 1, 1969