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By Neil Campbell

"The gently-dipping Devonian dolomite beds south of Great Slave lake in northern Canada are nearly every-where concealed by a cover of glacial drift and muskeg. Nevertheless, in 1898 or earlier, four small outcropping areas of dolomite, richly mineralized with lead and zinc sulphides, were discovered. Exploration work performed here up to the end of 1930, included intensive trenching and drilling of the showings, together with mapping and wide-spaced drilling in the surrounding region. This work proved that the discoveries are isolated pockets of mineralization much too small to be commercially valuable by themselves. No evidence of orebodies elsewhere was reported.Meanwhile, mapping by the G.S.C. in the Shield far to the east disclosed major Precambrian faults, some of which can be projected southwesterly (under a cover of Paleozoic sediments) to the vicinity of Pine Point. During the period from 1940 to 1947, consideration was given, by The Consolidated Mining and Smelting Company Ltd., to evidence of a theoretical possibility that, although apparently dormant in Paleozoic times, these faults may have provided a structural control and a source of ore-bearing solutions in some post-Devonian period. From this, it was postulated that the breaks might have created, in the overlying dolomite, a linear array of orebodies concealed by overburden but lying in a belt of considerable length and in a position predictable within practical limits. A program of drilling designed to test and exploit this specific concept was conducted from 1948 to 1955.he drilling within the new, theoretically-defined search area resulted in the discovery of many lead-zinc ore-bodies, none of which was exposed at the surface. Some of these are large and (as indicated by 1965 production records) very rich. They are situated 1 to several miles distant from, and apparently not connected to, the earlier-known surface discoveries. The drilling also disclosed that the ore, which consists of disseminated sphalerite and galena replacements together with colloform sphalerite and coarse galena cavity fillings, occurs mainly at certain stratigraphic horizons within a large, coarsely-recrystallized dolomite barrier reef. Considerable fracturing and folding was found. It has been suggested that reef development was influenced by post-Precambrian tectonic movements associated with the old faults in the basement complex. The ore may have been deposited by solutions moving from distant sources to favourable structural and chemical environments in or related to the reef.In more recent exploration performed in the course of preparing for mining production, the rate of ore discovery within the same general geological context has been greatly accelerated by the use of new geophysical techniques and drilling equipment. Reserves of 21.5 million tons, averaging 4 per cent lead and 7.2 per cent zinc, were reported in 1965, and production from open pits at the rate of approximately 248,000 tons of concentrates per year is in progress"

Jan 1, 1966

By Dale L. Pitt

Introduction In opening up a new country, one of the most vital problems is that of transportation Without roads, railways, or water routes, development is very slow because these are the arteries through which the life-blood of the country flows. British Columbia is unusually fortunate in having along its western coast, for some 600 miles, a stretch of inside water unequalled, for comfortable and safe navigation, by any other similar stretch of ocean in the world. This solves in a general way the major north and south transportation problem for the coast section, and offers comparatively cheap rates for the shipping of all commodities. The principal cities and centres of distribution will naturally grow up on the coast. These cities, however, must have methods of communication with the hinterland, and it is the necessity of supplying these, as feeders to the principal ports, which presents problems of considerable magnitude.

Jan 1, 1930

By M. Laframboise, M. Buarzaiga

High-pressure acid leaching (HPAL) of nickel laterites has received considerable attention in recent years. High paymetals extraction, good selectivity, and advances in pressure hydrometallurgical technology are some of the reasons for this interest. Falconbridge Limited (Sudbury. Ontario) investigated the HPAL process using both fresh water and seawater for ore processing. The use of seawater resulted in a chloride concentration of 7.8 g/L in the autoclave feed. A test program was developed to study the effect of process water and leach temperature on the leaching behaviour of different ore compositions from the Koniambo deposit in New Caledonia. The work showed that salinity has a major effect on autoclave chemistry. This paper explores the results.

Jan 1, 2004

By M. A. Rabah

This study aims to recover europium, yttrium metals, some valuable salts or oxides from the white powder (apatite) coating the inner surface of spent florescent lamps (SFLs). Pressure leaching using sulphuric/nitric acid successfully dissolved the metals of interest. Europium or yttrium metals were obtained by hydrogen reduction of their oxides. Addition of potassium thiocyanate converted the dissolved sulphates to thiocyanates. Selective separation of Eu and Y was then carried out by solvent extraction from the thiocyanate solution. The used solvent was trimethyl-benzylammonium chloride. N-trihutylphosphate in 1 M nitric acid was used to strip the metal loaded in the organic phase. Results showed that the quality of the cleaned glass tubes of the SFL met the standard requirement for the lamp manufacture. The white powder (WP) is composed of calcium sulphate 35.2%, phosphate 61.5% and oxides of europium and yttrium 1.65%wt. respectively. Autoclave digestion of the WP for 4 h at 120°C and 500 kPa in sulphuric acid/nitric acid mixture dissolved 96.4% of yttrium and 92.8% of europium. The conversion rate of sulphate to thiocyanate was favoured at low temperature. Stripping of Eu and Y from the loaded organic phase behaved in an opposite way. A metal separation factor of 9.4 was obtained. ate recovered europium and yttrium salts were selectively separated using ethyl alcohol or dilute nitric acid. Yttrium was very soluble while europium was not. Europium and yttrium metals were obtained by hydrogen gas reduction at 850°C and 1575°C respectively.

Jan 1, 2004

By George P. Demopoulos

For more than 20 years the author had the privilege of working closely on a number of R&D projects with Lucy Rosato and her team at CEZinc. Several of these projects were driven from the sustainability agenda that Lucy Rosato championed as an innovation leader that supported research collaborations. Highlights from this highly rewarding collaboration are to be presented in this paper. In particular we will deal with the following works-topics: (a) iron control via solvent extraction as alternative to jarosite precipitation; (b) production of high-density gypsum by controlled neutralization of simulated zinc plant process/waste waters; (c) selenium removal from weak acid solutions; (d) electrolyte purification by cementation; and (e) manganese control by oxidative precipitation with SO2/O2.

Jan 1, 2015

By O. G. Olvera

"Refractory sulfidic ores consist of materials in which gold occurs finely disseminated within metallic sulfides or forming solid solutions, with pyrite and arsenopyrite being the two sulfides most commonly associated with gold. Typical cyanide operations show poor performance and require oxidative pretreatments to increase gold recovery. Pretreatment alternatives include roasting, pre-aeration, acidic and alkaline high pressure oxidation, and bacterial oxidation. The presence of arsenic, however, introduces a serious disadvantage to the use of roasting and bacterial leaching, while high pressure oxidation involves high capital costs. This work focuses on evaluating the effect of the addition of a carbon resin as a sulfur collector on the oxidation of different arsenopyrite concentrates under atmospheric tank leaching (ATL) conditions. The addition of the resin improved the oxidation of sulfides and favored the formation of elemental sulfur over the generation of sulfate. The use of AF5 in ATL resulted in higher gold recoveries under standard cyanide carbon-in-leach and thiosulfate leaching.INTRODUCTION Refractory sulfidic ores consist of materials in which gold occurs finely disseminated within metallic sulfides or forming solid solutions, with pyrite and arsenopyrite being the two sulfides most commonly associated with gold. Gold is not readily accessible to solutions in these types of ores and typical cyanide operations show poor performance, thus making the use of oxidative pretreatments a requirement to increase gold recovery. Pretreatment alternatives include roasting, pre-aeration, acidic and alkaline high pressure oxidation, and bacterial oxidation. The presence of arsenic, however, introduces a serious disadvantage to the use of roasting and bacterial leaching, while high pressure oxidation involves high capital costs. The use of carbonaceous materials to enhance the dissolution of sulfides is not novel, and leaching additives such as coal, activated carbon and carbon powder have been considered for the improvement of bioleaching, atmospheric leaching, and pressure oxidation leaching processes. However, this type of technology has been focused mainly on the recovery of copper from copper concentrates containing chalcopyrite with less attention paid to other sulfides."

Jan 1, 2017

By M. Nusheh, C. Bumby, A-H. Puichaud

"Vanadium-bearing titanomagnetite ironsand deposits occur along a 480 km stretch of the west coast of New Zealand. In the present study, the leaching behaviour of NZ ironsand was investigated in hydrochloric acid (2–10 M) solution at 50–80°C for 2 h. The resulting leaching liquors exhibited Fe/V ratios in the range 150–180. The distribution of trace element contaminants between solution and solid residue was investigated, and processing conditions have been determined for rapid and efficient dissolution of Fe, Ti and V into the leaching solution. In addition, mineralogical analysis of raw ironsand and leached residues was performed in order to study the leaching mechanism. Samples were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy (EDX), X-ray fluorescence spectroscopy, qualitative and quantitative X-ray diffraction and inductively coupled plasma mass spectrometry (ICP). Results indicate that the dominant dissolution process follows shrinking particle mechanism. However, ironsand particles containing ex-solution lamellae exhibited a different leaching behaviour compared to homogenous titanomagnetite particles.INTRODUCTION Titanomagnetite ironsand (blacksand) forms Quaternary onshore beach and dune deposits and offshore marine deposits (Figure 1) along 480 km of coastline from Kaipara Harbour south to Wanganui on the west coast of the North Island (Christie, 2016). It attracted the attention of scientists from the earliest times (Galbreath, 1998). The principal minerals in ironsand are titanomagnetite (TTM), ilmenite, quartz and ferromagnesian minerals such as augite, hornblende, diopside, and olivine with smaller amounts of rutile and apatite (Mauk, 2016).Several large ironsand deposits have been discovered and exploited since the late 1960’s. The Waikato North Head and Taharoa mines are currently operating and they have a 2015 measured resource of 400 million tonnes in total and provide over 2 million tonnes of concentrate per year by simple cost effective magnetic separation process (Christie, 2016; Christie & Brathwaite, 1997). The concentrate contains not only 7–8% TiO2 and 56–60% SFe, but also 0.3–0.6% V2O5, is both a valuable titanium mineral and a source of vanadium. All the production is used for steelmaking industries. The other potential for utilizing more of this resource without requirement of integration into an iron and steel producing plant is to develop a hydrometallurgical route with advantages of higher efficiency along with lower emissions. Currently, there is no existing commercial process capable of extracting all three of these elements as industrial-grade commodity products. Acid leaching of TTM concentrate with higher degrees of recovery and selectivity is a key step in any possible hydrometallurgical route."

Jan 1, 2017

By W. Leblanc, J. C. Marsh, D. Kettle, J. Tompkins, G. Hartley

"The Lingan Mine is the newest of the four operating collieries of the Cape Breton Development Corporation and is located on the east coast of Cape Breton Island. Development of slopes began in 1969 using four Dosco Roadheaders. Production commenced in October 1972, when a partial extraction section utilizing a continuous miner, loader and shuttle car was installed. A second Joy unit is scheduled to begin production early in 1973. This paper describes the production and development operations, the ventilation system and the equipment in use at the mine."

Jan 1, 1973

By H. A. Halupka, I. A. Mozer

"At its plant in San Juan, Peru, Marcona Mining Company operates two grate pelletizing furnaces for the agglomeration of 3.5 million long tons of magnetic concentrates annually. Line One, installed in 1963, was built by Lurgi as a downdraft process furnace utilizing a furnace fan for the recuperation of hot gases from the cooling zone. This line was modified in 1966 to include both updraft drying and downdraft drying, and the original roof burners were converted to side-wall burners. Line Two, a Dravo-Lurgi furnace with an annual capacity of 2.4 million long tons, was built in 1966. This line, in contrast to the modified Lurgi furnace, employs direct recuperation of hot gases from the cooling zone and utilization of process gases from the firing zone for updraft drying.At its plant in San Juan, Peru, Marcona Mining Compa-ny operates two grate pelletizing furnaces for the agglo-meration of 3.5 million long tons of magnetic concentrates annually. Line One, installed in 1963, was built by Lurgi as a downdraft process furnace utilizing a furnace fan for the recuperation of hot gases from the cooling zone. This line was modified in 1966 to include both updraft drying and downdraft drying, and the original roof burners were converted to side-wall burners. Line Two, a Dravo-Lurgi furnace with an annual capacity of 2.4 million long tons, was built in 1966. This line, in contrast to the modified Lurgi furnace, employs direct recuperation of hot gases from the cooling zone and utilization of process gases from the firing zone for updraft drying. 5 per cent increased capacity, 30 per cent lower fuel oil consumption, and approximately 400 per cent reduction in grate bar and pallet corrosion. Firing of the pellet bed was improved by conversion from roof to side-wall burners. This modification also permitted utilization of monolithic refractory in place of pre-fired shapes, thereby improving over-all furnace availability and reducing refractory stock requirements from 154 different shapes to 18.Data are presented to compare operating performance of the Dravo-Lurgi furnace and the modified Lurgi furnace. These data show 30 per cent lower fuel oil consumption and 10 per cent higher capacity per unit grate area for the Dravo-Lurgi furnace, which also averages higher availability due to greater operating flexibility."

Jan 1, 1970

By Da-Qiang Cang, Qingde Wang, Wei Wang, Wen-Bin Dai, Min Guo, Yu Li

Utilization of both slag and its heat for hot slag is a great challenge for iron and steel industry. Many methods of hot slag modification for directly converting hot slag into value-added materials were researched in recent years, and waste heat of hot slag could thereby be transformed into inner energy or chemical energy of the materials. In this paper, an experiment of converting hot slag directly into glass ceramics by hot slag modification method was conducted. A cooled modifiers mainly composed of fly ash were firstly heated though a cyclone furnace and then fell into a molten bath to mix with hot steel slag. Half of hot slag was used as raw materials and accordingly about half energy consumption, about 5MJ/kg for melting raw materials was saved in the process compared with that of traditional producing method. Frit quenched from the modified hot slag had a higher basicity of 0.6-0.7 than traditional frits in order to reduce the needed amount of cold modifiers and accordingly utilize more hot slag and its waste heat. Glass ceramics were further prepared from the frit and a heat treatment of one-stage method is more suiter to such frit than that of two-stage method. The glass-ceramics with basicity of 0.6 and heat-treated by one stage method had the best performance with bending strength of 146.46 MPa, Vickers hardness of 6.79 GPa, water absorption rate of below 2% and shrinkage rate of around 10%.

Jan 1, 2015

By Peter A. Hacquebard

Recent drilling programs have shown that the in-situ coal resources of Nova Scotia are very substantial. The grand totals of the measured, indicated and inferred categories amount to 232 m, 646m and 993 m tons, respectively. This vast quantity of coal occurs essentially in five main fields: Sydney, Mabou, Port Hood, Pictou and Springhill. The largest resources (84% of the total) occur in the submarine area of the Sydney coalfield. With a 65% recovery rate, there are at present 150m tons of proven, recoverable coal in Nova Scotia. At a predicted maximum annual production of 5 m tons, this amount equals a lifespan of 30 years. However, additional drilling, particularly in the Sydney offshore area, holds promise of increasing the recoverable reserve tonnage to at least 350 m tons. This figure may be compared with the 484 m tons production obtained during 191 years of mining (from 1785-1976). The geological appraisal of the remaining coal resources in the five fields mentioned is presented in three-dimensional diagrams, per individual seam and corresponding reserve area. In addition, the submarine extensions of the Sydney and Mabou coalfields are discussed in light of results obtained from off shore oil exploration wells. The terminology and standards of coal resource calculations are pointed out, and the phenomenon of seam splitting and its prediction from geological data is illustrated. The availability in Nova Scotia of either thermal or metallurgical coal is considered in relation to rank and sulphur content. This paper was presented in June 1977 at the 90th Annual Meeting of the Mining Society of Nova Scotia. The coal resource estimates, however, have been updated to include the results obtained with the offshore drilling in the Sydney Coalfield to November 1977.

Jan 1, 1979

By T. A. Utigard, S. Pedler

Ilmenite from the Everett deposit in Quebec was characterized both chemically and mineralogically. The sample investigated contained the following main components: 40% Fe2O3, 21% TiO2 and 21% SiO2. The ilmenite grains contained about 20 to 25% hematite intergrown blades, with widths ranging from 2 to 30 \u03bcm. Crushing the sample to less than 0.85 mm led to significant liberation of the ilmenite from the gangue minerals. Gravity separation followed by magnetic separation of this size fraction led to a TiO2 concentrate grading of about 30% TiO2, with a recovery of 94%.

Jan 1, 2010

By C. M. Diaz, P. J. Mackey

Since its inception, in 1987, the Copper-Cobre series of conferences has established itself as the prime world forum for discussing advances in copper process metallurgy, in particular copper sulfide smelting, copper recovery by leaching and electrowinning and copper electrorefining. All copper producing countries have actively participated in the pyrometallurgy symposia held in the framework of these conferences. In 1999 and 2003, the close to 100 pyrometallurgy papers that were presented had to be accommodated in two volumes. In the present paper, the authors firstly provide a brief historical sketch of the Copper-Cobre conferences and then focus on providing a retrospective look at the dramatic changes that have taken place in copper smelting in the last few decades, primarily as discussed in the Copper-Cobre and precursor conferences pyrometallurgy proceedings. Topics include: the development of autogenous, increasingly more intensive, environmentally sound and energy efficient smelting processes; significant improvements in Peirce-Smith converting practice and at the same time the commercialization of alternative continuous converting routes; the consequent expansion and modernization of smelters; the increasing compliance with strict government environmental regulations in most copper producing regions of the world; the realignment of the copper smelting industry throughout the world; and trends in copper smelting R&D. A look at the future closes these reflections on the contribution of the Copper-Cobre conferences to the advancement of copper smelting technology.

Jan 1, 2007

By R. A. Campbell

Pig iron and silicospiegeleisen were produced experimentally from a very low-grade manganiferous iron ore from Steep Rock, Ontario, by a two-stage electric smelting process. The most favourruble operating conditions were determined for each stage. Cement clinker then was made by calcining the slag from the second stage of smelting, with additional limestone and alumina. (This slag would normally be a waste material). The cement clinker produced had the composition of commercial Portland cement, and met the physical test requirements of the Canadian Standards Association Specification A5-1951 for normal Portland cement as well as could be expected for a material produced on .such a small scale.

Jan 1, 1958

By M. A. Halim, V. I. Lakshmanan

Recycling is one of the key elements for sustainable process development for the recovery of value-added products and reducing environmental impact. Process Research ORTECH Inc. has developed several innovative and sustainable technologies, which minimizes the use of water, and chemicals for the recovery of gold, vanadium and gallium from secondary sources by maximizing the recycling of reagents, and reuse of water from process effluents.

Jan 1, 2015

By S. Vongpaisal, T. R. Yu

"A set of new blast damage criteria has been developed, with special reference to blasthole mining operations, for assessing damage by incorporating the vibration level, rock properties, site characteristics and the effects of ground support systems. The main objective of this work was to provide a database with reasonable accuracy for use in optimizing blast design, numerical analysis and ground control expert system module development.The new damage criteria allow one to estimate the degree of damage to rock structures in terms of a dimensionless parameter defined as Blast Damage Index (BDI). This allows for the description of blast damage in a unified form, and facilitates the development of codes for numerical modelling to express the degree of blast damage universally. A number of field investigations from several stope production and slot opening blasts at a large underground base metal mine were carried out to verify the developed index. The results show a good correlation between the observed damage and the type of damage predicted from the BDI values.Practical measures are also provided for minimizing blast damage in large underground blasthole mining operations"

Jan 1, 1996

By F. M. Doyle, G. Sidhu, A. J. Dussault, A. Raygani

There is a growing demand for rare earth metals for use in high strength permanent magnets, most notably Nd2Fe14B. Rare earth metals are extremely reactive, with reduction potentials around -2.5V SHE, and are conventionally produced by molten salt electrolysis. The current work was done to investigate an earlier report of electrodeposition of a neodymium ferroalloy from aqueous solution, to determine whether this approach could be an environmentally and economically competitive commercial approach for producing feedstock for permanent magnets. Such a process would be analogous thermodynamically to the Castner- Kellner process, in which aqueous sodium chloride brine is electrolyzed in cells with mercury cathodes. Metallic sodium forms an alloy (amalgam) at the cathode, thereby lowering the activity of the metallic sodium significantly below unity and making the reduction potential of sodium significantly less negative than the standard reduction potential. Here we report the effects of Nd/Fe ratio in the electrolyte, current density, temperature and two different complexing agents, glycine and cysteine, on the composition and morphology of the electrodeposits, along with current efficiency. The energy needed to produce neodymium as Nd:Fe alloys by aqueous electrodeposition was compared with values estimated for production by molten salt electrolysis and the thermodynamic energy requirement.

Jan 1, 2014

By Robert B. Parsons

"Next month will mark the anniversary of the release of an important federal study on a mineral policy for Canada. The study, entitled ""Mineral Policy-A Discussion Paper"", provides well-researched coverage of a broad range of issues that are of interest to the mining industry. Unfortunately, there is a real possibility that the discussion paper will wither and die on the vine, unless the federal and provincial governments, and the private sector, collectively ensure that some of the key considerations which are raised by the paper are acted upon.IntroductionAlmost one year ago, on March 8, 1982, Federal Mines Minister July Erola released an important study entitled ""Mineral Policy-A Discussion Paper"". The discussion paper, which presents the government's assessment of the opportunities and constraints facing the Canadian mineral industry in the 1980s, was prepared within the context o f three principal objectives-strengthening the resource base on which the industry rests, ensuring the adequacy of research activities needed to support development of the resource, and furthering the development of markets for the resource It is clear that, in today's economic climate, not even the most generous incentives would turn the industry around: what is needed is a sound base for future development, when this is possible. In this regard, the discussion paper is an excellent stepping stone, in that it reviews a wide range o f fundamental policy issues which touch on all facets o f the mining industry."

Jan 1, 1983

By Guoqiang Lan, Jun Song, Bin Ouyang

Rare-earth pyrochlores, commonly exhibiting anomalously low lattice thermal conductivities, are considered as promising topcoat materials for thermal barrier coatings. However the structural origin underlying their low thermal conductivities remain unclear. In the present study, we investigated the phonon properties of a group of RE pyrochlores, Ln2Zr2O7 (Ln = La, Nd, Sm, Gd) employing density functional theory and quasi harmonic approximation. Through the relaxation time approximation (RTA) with Debye model, the thermal conductivities of those RE pyrochlores were predicted, showing good agreement with experimental measurements. The low thermal conductivities of RE pyrochlores were shown to largely come from the interference between the low-lying optical branches and acoustic branches. The structural origin underlying the low-lying optical branches was then clarified.

Jan 1, 2015

By Ben Habermann

"The object of the work described in this paper was to increase the understanding of the relation that capillary pressure of a rock, hydro-dynamics, and accumulation of oil in stratigraphie traps have to one an-other. The hydrodynamic oil-water tilt equation is derived by considering the two vector gradients involved: (1) buoyancy of oil in water and (2) hydraulic gradient.Recent theories show the necessity for oil to have a continuons phase in the reservoir rock in order to mi-grate; this fact applies to hydro-static as well as to hydrodynamic conditions. Hydrostatically, the displacement pressure of the rock deter-mines the amount of oil that can be trapped behind a permeability barrier. If the buoyancy of oil in water exceeds the displacement pressure, oil will migrate up-dip; an oil trap will be formed where displacement pressure is greater.In stratigraphie traps the pressure drop caused by moving water is positive when its direction is down-dip, helping accumulation; and it is negative when its direction is up-dip, forcing the oil into the tighter section of the reservoir. Theoretically, pro-vided we have data such as: (1) the displacement pressure of an up-dip permeability pinchout, (2) density difference between the oil and water in place, and (3) the direction and magnitude of the hydrodynamic gradient (if any), the possible extent of a stratigraphie oil accumulation down-dip can be predicted.To test the above theory sample cores from three wells in the Denver Basin were analyzed and the oil column that could be held under hydro-static conditions was calculated. After the hydrodynamic influence was considered, the results were compared with actual field data.The significant fact shown by this investigation is that the calculated oil column in one reservoir very closely approximates the actual extent of the oil column in a well. Also in accordance with the theory, the capillary pressure caused by the buoyancy of the oil column exceeded the measured displacement pressure on core samples from another productive field. For very tight shaly sand and questionable oil shows, the interpretation of data is very critical, as shown by experiments on core samples from a third field."

Jan 1, 1960