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By W. S. Hargratt

THE present era of exploitation of the Little Long Lac and Sturgeon River areas commenced in 1925, when Beardmore Gold Mines started development of what is now the property of Northern Empire Mines. A shaft was sunk in 1927-28 and a very limited amount of underground work was carried out, following which the property was shut down. It remained idle until 1932, when Empire Star Mines, a Delaware Company, optioned the property. This Company formed the Northern Empire Mines Company, Limited, to operate the mine, and immediately instigated an aggressive programme of surface and underground development. By the summer of 1933, sufficient ore was indicated to justify the installation of a small mill. The decision was also reached to bring in electric power. A power-line was built from Hydro, the Ontario Power Commission's development on the Nipigon river, to the mine, a distance of approximately 50 miles. This work was entirely financed by Northern Empire Mines. Mill construction was commenced in October, 1933, and completed by March, 1934, thus making this mine the first producer in this district.

Jan 1, 1940

By C. Pichler, C. Benigni, J. Antrekowitsch

"The recycling of steel mill dust results in zinc oxides which are sold to the primary industry in or-der to recover zinc in its metallic form. Due to the contained impurities - chlorine and fluorine - these sec-ondary oxides are usually charged into the roaster together with primary concentrates. Appearing problems in this furnace limit the application of secondary materials. Based on the zinc amount, a direct leaching, assumed that a low halide concentration is present, would be possible. To use the zinc solution directly in the electrowinning stage, the concentration of impurities, first of all iron, is limited. Iron can be found in secondary zinc oxides due to carry over during the recycling process. In order to reduce the iron content in the solution, the leaching has to be pH-controlled. This leads to a limited number of simple purification steps before the solution enters the electrolysis. Various trials were performed to evaluate the influence of temperature, time and sulphuric acid concentration on the iron dissolution. This paper deals with the results and also focuses on other impurities such as halides. Additionally, the soda washing process, usually done with secondary zinc oxides to remove most of the halides, and the challenges within this step are discussed.INTRODUCTION Recycling of steel mill dust, which is the main zinc containing residue, in the Waelz process dis-plays the common method worldwide. The product of the process is a secondary zinc oxide which is con-taminated with different elements like lead, iron and halides due to mechanical carry over or evaporation. Depending on the feeding material the concentration of each element in the dust is varying. The zinc con-tent of the product, also called Waelz oxide, lies around 65–68%. Based on these values it presents an al-ternative to the primary concentrate for the production of metallic zinc. The contained halides limit the direct utilization in the leaching stage and therefore have to be reduced. State of the art is a soda washing process but also solvent extraction gives a possibility to remove chlorine and fluorine but the desired con-centration for the electrolysis is hardly reachable (Antrekowitsch et al., 2016) Iron is present as an undesirable component of such secondary zinc oxides due to carry over. During the hot acidic leaching of the secondary concentrate, iron is dissolved too. Based on the higher electrical potential iron has to be removed before the zinc solution enters the electrowinning stage. It is usually removed by precipitation as goethite, hematite or jarosite, which is the common precipitation residue (Ismael et al., 2003)."

Jan 1, 2017

By O. E. Andrew

THE object of this paper is to present a brief summary of the dust control system in use on the 3,825-foot level at the jaw crusher station, Lake Shore mine. During the years 1936 and 1937, dust survey reports were presented to the management showing that high dust concentrations were being created during operating periods. At that time, however, this crusher was running only an hour or so each shift, and it was felt that no large capital expenditure for dust control equipment could be justified. In order to afford some protection to the operators, a number of respirators then on the market were .tested and the 'Comfo' respirator was adopted for use by the crusher-men. In 1938 this crusher began to handle a large share of the total mine tonnage and the hours of operation were increased. Further dust sampling showed increased dustiness with the longer operating time. It was also realized that the operators suffered considerable inconvenience if they wore their respirators throughout the shift. If the respirators were not worn, then dangerous amounts of dust were being inhaled. The fact that the crusher station was situated on the 3,825-foot level limited the means that could be employed to eliminate the dust hazard. At that rime there was not available the 5,000 c.f.m. of fresh air which would be required to sweep out or dilute0 the dust, and there was also no way of disposing of the contaminated air without passing it on for other men to breathe. Thus it became apparent that a self-contained dust disposal system would have to be installed.

Jan 1, 1941

By F. Roemer, D. Goldmann, T. Elwert

Tantalum is an important minor metal for the production of high performance capacitors. Approximately 60% of the annual tantalum production is used in this application. Despite its high price of 298 US$/kg (average price 2010–2014), at the moment, no recycling from end-of-life products takes place. In the established recycling processes of waste electrical and electronic equipment (WEEE), tantalum is lost in the slags of copper smelting, where it is highly diluted. An economic recovery is not possible at that point. Although tantalum must therefore be extracted from the WEEE stream before it enters smelting, no industrial recycling processes exist. The main reasons are its low concentration in the WEEE stream, lack of information about tantalum bearing devices, technical difficulties of extraction, and conflicts of interests regarding the recycling of other valuable metals in WEEE. In this paper, the results of a cooperation research project are presented. The aforementioned challenges are addressed and a novel tantalum recycling process is developed. Small pilot scale experiments show that a mechanical processing route can produce marketable tantalum-concentrates of 30% tantalum with yields between 60 and 70%. This is reached through a manual pre-sorting of potentially tantalum bearing products followed by a combination of an optimized comminution, sieving, air classifying, eddy-current (EC), and two stage magnetic separation. Key to the implementation of this process was a detailed survey of the tantalum concentrations in different products carried out by the industrial partner.

Jan 1, 2016

By G. Titichoca

Modification of the blasting process considers that any increase in the energy consumption generates greater benefits if done in the later stages (associated with a larger decrease in energy consumption). Therefore, although the blasting cost is doubled, generating a greater proportion of fines in addition to a weaker ore (because with greater loads and appropriate distribution of explosives a greater number of internal cracks is generated), the reduction of the unit cost that occurs in the grinding stages (SAG and ball mills) generates a positive balance in the overall size reduction process. Codelco Chile, Division Andina, has developed an extensive experimental plan to evaluate the concept of blasting modification applying greater energy. This was implemented in two stages, each including a specific mine sector: La Union and Don Luis. This paper reviews the experience of implementing such blasting modifications at the La Union mine and its impact on the design concepts and the operation of the SAG mill plant

Jan 1, 2007

The properties required for a com-pound to form useful thermoelectric materials are described. Uranium compounds which might have these properties are reviewed. Several of these compounds have been prepared and fabricated into compacts. The apparatus used for hot pressing, and for the measurement of thermoelectric power, electrical conductivity and thermal conductivity, is described. Detailed attention has been given to the properties of the nitrides. Preliminary studies on a number of other uranium compounds are reported. The figures of merit of the best materials so far examined are one-tenth of those necessary for a useful thermo-electric material. THE efficiency of thermoelectric materials for power generation and cooling is determined by their figure of merit, Z = a2 a/K, where a, a and K are thermoelectric power, electrical conductivity and thermal conductivity, respectively. It is well known that the largest values of Z are achieved with semiconductors (1). High mobility of charge carriers is necessary for simultaneously high thermoelectric power and electrical conductivity.The properties required for a com-pound to form useful thermoelectric materials are described. Uranium compounds which might have these properties are reviewed. Several of these compounds have been prepared and fabricated into compacts. The apparatus used for hot pressing, and for the measurement of thermoelectric power, electrical conductivity and thermal conductivity, is described. Detailed attention has been given to the properties of the nitrides. Preliminary studies on a number of other uranium compounds are reported. The figures of merit of the best materials so far examined are one-tenth of those necessary for a useful thermo-electric material. THE efficiency of thermoelectric materials for power generation and cooling is determined by their figure of merit, Z = a2 a/K, where a, a and K are thermoelectric power, electrical conductivity and thermal conductivity, respectively. It is well known that the largest values of Z are achieved with semiconductors (1). High mobility of charge carriers is necessary for simultaneously high thermoelectric power and electrical conductivity.

Jan 1, 1963

By R. E. Martin

"The Westerose Leduc (D-3) pool, a Devonian reef reservoir situated in Central Alberta, Canada, has now been producing for over seven years. As a unit operation, the pool pro-vides an interesting example of the full exploitation of gravity segregation tendencies. The reef has a 238-foot oil column, underlain •by bottom water and over-lain by a substantial gas cap. The original hydrocarbons in place were 147.96 million STB oil and 94.4 MMMCF of Taw gas cap gas. Nine-teen producing wells on 80-acre spacing have been completed, most of which are highly productive. Gas injection operations return solution gas to the gas cap. A study of the rock and fluid properties of the pool show it to be conducive to production by gravity segregation at high rates. Monthly average producing rates have varied between 800 B/D and 8,000 B/D and have recently totalled 3,000 BID to 5,000 B /D. Recovery and performance predictions under partial pres-sure maintenance at 10,000 BID indicate an ultimate recovery of 66 per cent of the original oil in place. In the absence of pressure maintenance, recovery would be only slightly less."

Jan 1, 1960

By G. W. Neumann, J. R. Schnarr

The lead-zinc-copper-silver ores mined by Brunswick Mining and Smelting Corporation Limited at their No. 12 underground mine and No. 6 open-pit operation, and treated by distinct concentration processes in separate plants, present difficult metallurgical problems because of the extremely fine dissemination of the valuable minerals with pyrite and pyrrhotite. The problem of concentration is further complicated, in the No. 12 ore, by the presence of a varying content of graphitic carbon. This paper describes the milling of No. 12 ore and the production of copper, lead and zinc concentrates by differential flotation.

Jan 1, 1971

By R. Stratton-Crawley, S. W. Wilson

"Inco's Matte Separation Plant is a unique mineral processing facility having no process tailings stream. Each product is a high-grade concentrate with strict assay specifications which are defined by the downstream refining route. The most recent column application in the flowsheet, copper scavenging in the production of a high quality nickel concentrate, is described in detail. Testwork in pilot-scale columns (0.038 m, 0.051 m and 0.10 m in diameter) was used to develop a model of the copper scavenging system. This data was then used to simulate the performance of plant-scale equipment. The relationships thus established were confirmed by a series of plant tests in a 1.8 m diameter column. Column results consistently exceeded conventional cell performance. The modelling was extended to assess full plant production requirements and, as a result, a 2.1 m diameter column was specified for this application. Engineering design for this column is currently underway and the column is scheduled to be commissioned later in 1991.INTRODUCTIONMatte SeparationINCO's Matte Separation Plant is a part of the Copper Cliff Smelter complex near Sudbury Ontario. The flowsheet and the development of column flotation within it have been described previously (Feeley et al., 1987, Wilson et al., 1989). The plant feed is a synthetic Bessemer Matte from the Nickel smelter. This matte is slow cooled to promote grain growth and typically assays 46-52% Ni, 23-27% Cu. These elements are present primarily in sulphide form (Ni3S2 and Cu2S respectively) with some metallic alloy also precipitating from the sulphur deficient matte. Minor amounts of iron, precious metals, and nuisance elements are also present.The matte separation process is, in concept, relatively simple. Following magnetic removal of the metallic alloy from the feed, the flowsheet is designed to float a high grade copper concentrate from the nickel sulphide matrix. A simplified flowsheet of the process is shown in figure 1."

Jan 1, 1991

By O. Herstad, J. M. Toguri, K. Grjotheim

DURING the last three years, investigations on the aluminum reduction of magnesium-bearing compounds have been initiated at the Institute of Inorganic Chemistry, The Technical University of Norway. The results of these investigations are reported in this paper. Very little information exists in the literature on the reaction between magnesium compounds and metallic aluminum. The available information itself is conflicting, and, to clarify the existing discrepancy, the reactions between aluminum and magnesium oxide (MgO), caJcined dolomite (CaO . MgO) and olivine (Mg2SiO.) were studied. The logical approach for the study of these reactions between condensed states with the formation of a gaseous phase is, ( 1) the measurement of the equilibrium vapour pressure of the gas, in this case magnesium, associated with the respective reactions and, (2) the identification of the end products of the reaction in order to establish the re-action scheme.

Jan 1, 1962

By Y. S. Sun, Northeastern University, W. B. Li, P. Gao, Z. Y. Zhang, J. W. Yu

"The boron-bearing iron concentrate was extracted from ludwigite ore by the process of magnetic-gravity separation. In order to fully utilize the refractory ore and meet the boron consumption of China, a novel process for separation of boron from iron in boron-bearing iron concentrate was proposed in this paper. In particular, laboratory scale experiments of improving boron reactivity were performed. Fine boron-bearing iron concentrate briquettes were reduced by bituminous coal completely at 1125 °C for 150 min. The effect of sodium carbonate, which was used as an additive in the roasting process, was investigated. The addition of sodium carbonate decreased the boron reactivity and facilitated the volatilization of boron. The influence of diverse cooling methods of the reduced samples on the boron reactivity was studied. The results indicated that boron reactivity could reach up to 80.76% when the reduced samples were cooled by rapid water quenching. In addition, the magnetic material containing 92.71 % Fe with a recovery of 95.11 % and boron-rich non-magnetic material containing 14.51% B2O3 with a recovery 88.85% could be obtained by low-intensity magnetic separation. The magnetic material and boron-rich non-magnetic material were good raw materials for steel-making and borax production, respectively.INTRODUCTION Ludwigite ore is abundant in Liaoning province of China, with 28.43 Mt B2O3 accounting for 57% of the boron resources of the country (Liu et al., 2006). However, it has not yet been utilized on an industrial scale due to its complex mineralogy and fine mineral dissemination (Wang, Wang, Ding, Ma & Xue, 2012). At present, boron-bearing iron concentrate and boron concentrate can be obtained from ludwigite ore using magnetic-gravity separation. The boron concentrate contains B2O3 12%~16%, which can be used as a high-quality raw material for the boron chemical industry after activated roasting, but the B2O3 content in the iron concentrate reaches up to 4%~6%. In order to further separate boron and iron from boron-bearing iron concentrate, a blast furnace and a solid pre-reduction followed by electric arc furnace melting have been proposed (Liu, Cui & Zhang, 1998; Wang et al., 2012). However, both of these two current routes face the same crucial problem that molten boron-rich slag has to be cooled slowly to obtain the alkali-dissolution activity of boron, which affects the yield of boron resource."

Jan 1, 2016

By F. McGravie, S. T. Solinski, W. W. Robertson

During this, the Centennial year of the discovery of the Hall-Heroult process, it seems appropriate to review some of the developments which have taken place in Canada and to explain why it has become an important world centre for the production of primary aluminum. For many years after it was recognized that the element aluminum existed, scientists were frustrated in their efforts to isolate it. In the early 1800s H. C. Oersted and Frederick Woehler prepared small quantities sufficient to measure some of the physical properties. A quasi-commercial process involving reduction with metallic sodium was developed by the French scientist H. St. Claire Deville in 1855 but the cost was very high ($30. 00 per kg). It was not until 1886 that Charles Martin Hall in the United States and P.L.T. Heroult in France, more or less simultaneously but completely independently, discovered the process which is essentially that in use today. Some of the early pioneers in the industry quickly recognized the potential of the hydro-electric resources in Canada as economic energy suppliers for aluminum production. The first commercial production in Canada was in Shawinigan, Quebec in 1901, only 15 years after the process was discovered. Subsequently operating plants were established at nine different locations in Canada (Quebec and British Columbia) (Table 1). Operations continue today in all locations except one (La Tuque). The table shows present plant capacity which for the older plants was reached in an evolutionary manner including replacement of obsolete capacity or upgrading and modernization of existing designs.

Jan 1, 1999

By N. Musee, N. Kornelius

This study presents a neural network approach to modelling the liberation of gold bearing ores. A complete mineralogical analysis of unmilled and milled ores, including gold deportment and gangue content are used as inputs to a self-organising neural net which generates order preserving topological maps. The arrangement and shapes of these clusters are coupled to unmilled free gold data to predict gold liberation in milled ores (absolute error: 4.2%). Moreover, the self-organising maps were diagnostic of the quality of data used, indicating that the relationship between particle size and gangue material content requires further investigation.

Jan 1, 2005

By E. Burdukova

Rheological measurements have found a wide array of applications in mineral processing research. Rheological properties of mineral suspensions are highly dependent on the mineral surface properties as described by DLVO theory, and the relationship between these properties and inter-particle interactions is well established. In this paper, rheological properties of mineral suspensions are used to study the differences in behaviour of isotropic talc and anisotropic zirconia minerals as a function of varying properties of the suspension medium, such as pH and polymer dosage, specifically carboxymethyl cellulose (CMC). It was found that the rheological tests when carried out in parallel with electrophoretic or point of zero charge measurements, clearly reveal differences between behaviour of the suspensions of isotropic and anisotropic minerals. These differences are further accentuated with the addition of carboxymethyl cellulose (CMC).

Jan 1, 2006

By Thomas Clark

This report presents a review of the distribution and exploration potential of platinum-group elements (PGE) in Québec; it is based on published and unpublished analytical data. This qualitative evaluation of the PGE potential, whether in PGE-dominant deposits or in Ni-Cu-dominant deposits with co-product PGE, is based on interelement ratios such as Ni/Pd, Cu/Ir, Cu/Pt, and Cu/Pd. Good PGE targets, i.e., deposits associated with magmas fertile in PGE, are identified. Less favorable PGE targets, i.e., deposits associated with PGE-depleted magmas, are also mentioned. The importance of exploring for deposits similar to those at lac des Îles and East Bull Lake (Ontario) is emphasized.

May 1, 2001

By A. Mitura

The paper presents the initial investigation of possible energetic applications of chosen wastes from groups: 06, 03, 05 and 01, including coal slimes being secondary product of hard coal processing. These categories of wastes are catalogued according to the polish law, where 06 ? wastes from production, preparation, purchasing and application of products of non-organic chemistry; 03 ? wastes from wood processing and from plates and furniture, celluloid mass, paper and card board production; 13 ? oil wastes and wastes from liquid fuels; 01 ? wastes produced by searching, extracting, physical and chemical processing of ores and other mineral raw materials. The change of combustion heat value was evaluated in produced energetic mixtures containing these types of wastes together with the change of their individual components. All combinations of ingredients were taken into consideration giving 256 various mixtures, from which 36 were selected to investigation. This allowed the performance of statistical factor analysis. For such prepared materials the application of regressive method was proposed in purpose of calculating combustion heat value and then the comparison of empirically determined and theoretically calculated heat values was performed. The change of regressive coefficients can be determined by the nature of Hess law (eq. 1) what was investigated and the attempt of its explication and validation was done.

Aug 1, 2013

By N. Erarslan, M. Ghamgosar

With the increased use of mechanized rock excavation, there have been developed internationally a number of methods to assess the abrasivity of rock materials. These methods range from determination of abrasive and hard mineral content using petrographic thin section analysis to weight loss or rate of wear flat development on specified test pieces. The Cerchar abrasivity index (CAI) test has been widely accepted for the assessment of rock abrasiveness and is determined as the abrasion of a steel pin after scratching over the freshly-broken or saw-cut surface of a rock. Two types of testing devices are in use today: (i) the original ‘Cerchar apparatus’, and (ii) the ‘West apparatus’, which was adopted herein. The CAI is calculated from the measured diameter of the resulting wear flat on the steel pin after 10mm scratching. This test has been considered to provide a reliable indication of rock abrasiveness for isotropic rocks. However, a great amount of rocks in natureis anisotropic. Phyllite is an anisotropic and foliated metamorphic rock and various types of phyllite specimens were tested in this research. Although phyllite is a type of rock primarily composed of quartz and the expected CAI value can be high, mechanical cutting of this rock should not be very problematic compared with igneous rocks have same CAI value. As phyllite is a foliated metamorphic rock, most of the specimens split into sheets through the quartz seam by the tip during scratching normal to the axis of quartz seams. Hence, viability assessment of Cerchar abrasivity test and F-Schimazek index values for the anisotropic rocks is investigated in this research.

Jan 1, 2015

By S. J. Laskowski

In potash ore flotation, carried out in NaCI-KCI saturated brine (about 6-7 molar KC1 and NaCI solution), long-chain primary amines are used as flotation collectors. Long-chain primary amines are poorly soluble in water and their solubility further decreases at high electrolyte concentration. For ionic surfactants there is a characteristic temperature (Krafft Point, KP) below which their solubility is too low for micellization. In a previous study, the effect of pH on the KP of dodecylammonium chloride in water was determined [Q. Dai and J.S. Laskowski, Langmuir, 7, 1361-1365 (1991)]. This paper deals with the effect of electrolyte concentration on the KP of dodecylammonium chloride. The derived theoretical relationship between the KP and the critical micelle concentration (CMC) for dodecylamine can be used to calculate the KP for electrolyte concentrations of up to 0.5 mol/L (about 8% NaCI-KCI brine). A simple experimental procedure for the determination of the KP for higher electrolyte concentrations is also described. The results show that the Krafft point of dodecylamine increases from about 17-18°C (in distilled water) to about 80°C at 16% brine saturation.

Jan 1, 2006

By J. M. Hong, H. K. Zheng, R. Hu, C. B. Zhou

The Jinping-I double curvature arch dam, located in the middle reach of the Yalong River and with a maximum height of 305 m, is the world highest dam of the same type that has been completed. Since the second and third periods of the reservoir impounding, after which the reservoir water level was raised by about 200 m, a significant amount of leakage was observed out of the drainage holes deployed in the lowest drainage tunnel at the left-bank abutment at EL. 1595 m, with a pressure of 0.3 MPa at one typical hole when it was blocked. In this study, a number of analyses including water quality analysis, digital borehole imaging, tunnel geological mapping and in-situ groundwater monitoring were performed to investigate the source of leaking, the leakage passages and the performance of the grouting curtains. An inverse modeling procedure combining the orthogonal design, finite element forward modeling of the transient seepage flow, artificial neural network and genetic algorithm was invoked to further evaluate the permeability of the foundation rocks whose permeability was underestimated in design, using the in-situ measurements of flow rate and piezometric head. The geological structures that lead to the leakage were identified and the seepage flow behaviors in the dam foundation and the left bank abutment were assessed. Given the connectivity nature of the sub-vertically oriented fractures that induce the leakage event, it is found that some of the drainage holes with relative larger amount of discharge could be closed or blocked for reducing the amount of leakage without remarkably increasing the pore water pressure in the foundation rocks.

Jan 1, 2015

By Bruce C. Fielder

"The concentration of uranium in orebodies discovered in the Athabasca Basin of northern Saskatchewan over the last 20 years has increased by a factor of 100. These high grade uranium orebodies are associated with high concentrations of radionuclides, complex mineralogy and an elemental makeup that includes base metals, arsenic, and molybdenum. Exploiting these high grade ores has required metallurgical advances in milling, tailings disposal and effluent treatment as well as changes in the design of uranium mills.This paper describes the most significant advances, including advances in dealing with the environmental issues which have become more prevalent in recent years. The milling processes of the Cluff Lake Mill, Key Lake Mill, Rabbit Lake Mill, and McClean Lake Mill are compared to illustrate both similarities and differences necessary for milling different orebodies.BackgroundUranium mining in Saskatchewan started in 1953 when the Beaverlodge Mine, owned by Eldorado Nuclear Limited (Eldorado), came into operation at Uranium City. Development in the Athabasca basin started in 1975 when the Rabbit Lake mine came into operation. This was followed by the start-up of the Cluff Lake mine in 1980 and the Key Lake mine in 1983. The McClean Lake mine is forecast to start up in the near future. The McArthur River mine recently received construction approval and the Cigar Lake Project and the Midwest Project are currently in the environmental approval process.The Beaverlodge operation ceased production in June 1982 after nearly 30 years of operation. The Rabbit Lake mill processed Rabbit Lake ore from 1975 until 1985, Collins Bay R-Zone ore from 1985 until 1993, and is currently processing ore from the Eagle Point mine (Bharadwaj, Jarvi and Lam, 1996). The Cluff Lake mill processed ore from the D- Orebody from 1980 until 1984. Since then the Claude orebody has been processed and the OP and DS orebodies are presently being milled (SRK. Senes and Melis, 1987; and Cogema Resources Inc. 1994 ). The Key Lake mill processed ore from the Gaertner ore body from 1983 until 1989 and Deilmann ore has been processed since (Cameco Corporation, 1992b and I 994a). Processing of McArthur River ore in the Key Lake mill is scheduled for 1999. The McClean Lake mill will be processing ore from the JLR, Sue and McClcan orebodies associated with the McClean Lake mine. In future ore from the Cigar Lake and Midwest projects will be processed in the McClean Lake mill. (Minatco Limited. 1991a)."

Jan 1, 1998