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By F. Keller, J. D. Edwards

THE anodic treatment of aluminum presents problems of scientific as well as of commercial interest.1-3 Of particular interest is the fact that, during the anodic oxidation process, the oxide continues to form at the metal-oxide interface under any oxide previously formed. This has led to speculation as to the mechanism involved in the formation of the relatively thick oxide coatings that are used commercially for decorative or protective purposes. Furthermore, the ability of certain types of oxide coatings to adsorb dyes and other substances has stimulated research to determine the actual structure of these adsorptive coatings. It has been found that anodic oxide coatings on aluminum are composed essentially of aluminum oxide. They are formed by the action of oxygen ions penetrating to the metal surface during the electrolytic oxidation treatment. These coatings can be formed in a number of different electrolytes, as for example, those which contain sulphuric acid, chromic acid, oxalic acid, or boric acid. These are the commonest and most useful electrolytes employed commercially. Except for certain specific conditions of formation, the coatings in general have been found to be amorphous alumina, as far as can be determined by X-ray or electron-diffraction methods. Anodic oxidation processes can be arranged in three rather general classes if they are grouped in relation to the solvent action of the electrolyte on the coating.4 In the first class, the electrolyte has little or no solvent action on the coating that is formed. In general, coatings produced under such circumstances are nonporous and non- adsorptive. In the second class, the electrolyte exerts an appreciable solvent action on the coating. These coatings are porous and adsorptive. Finally, for the third class, the electrolyte tends to dissolve the coating about as rapidly as it is formed. This action produces electrolytic brightening or anodic polishing of the aluminum surface and at most leaves only a very thin film of oxide. The nonporous and nonadsorptive type of oxide film is represented by the coatings that are formed when solutions of boric acid are employed as the electrolyte. It is especially significant that these impervious films are formed in electrolytes that exert little or no solvent action on the coating. Where a boric acid electrolyte is used, the coating tends to form rapidly, with the result that the flow of current is soon reduced to substantially zero. This indicates that the growth of the coating has stopped. As a rule, the thickness of the coating is roughly proportional to the voltage employed for formation and the coatings of this type are exceedingly thin. In an electrolyte of this type, the coating has a high resistance when the aluminum is made anode; consequently, any current that may flow (leakage current) is very

Jan 1, 1944

The pyrite-sphalerite-galena and barite orebodies at the Rosebery mine are concordant with the shale host rock and have been deformed into one system of folds with an associated axial plane cleavage. The folds are tight and overturned with east-dipping axial planes. Folds in the sulphide ore are commonly disharmonic, particularly between adjacent bands of different composition.Concentric style folds occur in the competent bands, e.g. pyrite-rich bands. Similar style folds are predominant in the less competent sphalerite-galena-rich bands and also in the shale of the host rock. The trends and plunges of the fold hinge-lines are variable but axial planes are of reasonably constant orientation throughout the mine area. The folds in the orebodies are of limited axial extent, approximating to conical folds, and are arranged in en echelon patterns. The fold system was possibly formed in one period of folding by heterogeneous strain that may have been caused by the presence of a mass of tectonically mobile sulphide ore. Lineations parallel to the ore/host rock contacts appear to reflect movement between the ore and the host rock during folding.

Jan 1, 1972

By B. Rezai

Impeller speed and air flow rate are two influence parameters on coarse particles flotation and collision and attachment angles. So, in this research recovery of quartz particles at four diameter classes carried out and collision and attachment angles investigated. It is found that maximum flotation response was observed at Impeller speed of 1100 rpm and 15 L/h air flow rate. For either more quiescent (Impeller speed<1100 rpm) or more turbulent conditions, flotation recovery decreased steadily. Furthermore, amount of attachment probabilities is calculated using suitable equation. According to this study, with decreasing particle size, air flow rate and impeller speed, probability of attachment increased and with increasing contact angle, probability of attachment increased. For various air flow rates, impeller speed and particle size, collision angle has been calculated. Maximum collision angle obtained at with 15 L/h air flow rate, particle size of 256 µm and impeller speed of 700 rpm and minimum collision angle obtained at with 45 L/h air flow rate, particle size of 545µm and impeller speed of 1300 rpm. In this study, maximum attachment angle, , was around 75 L/h air flow rate, particle size of 256 µm, contact angle of and impeller speed of 1300 rpm and minimum attachment angle was with 15 L/h air flow rate, particle size of 545 µm, contact angle of and impeller speed of 1300 rpm. ?82.72 ?64 cr??33.39 ?90 ?13.0 ?60

Jan 1, 2014

By Ahmad Rahbar-Kelishami, Zahra Karimi

When alumina is extracted from bauxite ore, one of the environmental pollutants created is known as red mud (RM). This study clarifies that the RM obtained from the Iran Alumina Company has a significant proportion of iron oxides (24%), alumina (19%), silica (17%), and calcium (21%), as well as trace amounts of other minerals. The elements in the RM can be removed and utilized again to reduce environmental pollution. Acid leaching is one of the best ways to selectively exclude some minerals from the RM. In this research, the RM is exposed to different inorganic acids, including HCl, HNO3, H2SO4, and H3PO4, and their binary mixtures. By comparing the results obtained from XRD, EDX, and SEM, it was discovered that CaSO4 crystals are formed by exposing the RM to sulfuric acid. Besides, phosphoric acid was only able to destroy the surface of RM particles. The XRD analyses of acid-washed residues demonstrated that except for the residue of HCl 5 N, all residues contain hematite, showing that inorganic acids cannot easily extract hematite from the complex phases of red mud. While the dissolution of RM with HCl or HNO3 will remove most of the calcium content of RM texture, increasing its iron oxide percentage, which may subsequently be utilized to make colors and pigments.

Mar 29, 2024

By M Saghaeian, V Sheikhzadeh, R Hejazi

Mining dilution is one of the most important factors affecting the economy of mining projects. Instead of quantifying dilution in mining studies, it is common to assume a general dilution such as 5 per cent for massive deposits. Dilution increases the operating costs in the plant by increasing the tonnage of material to be milled. It prolongs the mine life by reducing plant’s effective capacity. It also reduces the feed grade. In most cases, lower feed grade means lower plant recovery. Dilution also increases the cut-off grade, which in turn reduces the overall ore utilisation of a mine. In this study has been investigated applying pre-concentration by dry magnetic separation for decreasing of dilution impact on reserve estimation and open pit design in low-grade iron ore mine. Based on the preliminary open pit design and assumption 3 per cent as dilution factor, the mineable ore in life-of-mine (measured + indicated) has been estimated with Fe = 25 per cent, SiO2 = 49.7 per cent. Based on the experimental test work on the ore, by dry low intensity magnetic separation of dry HPGR product grinding circuit, it is possible to remove diluted waste material and liberated gangue before concentrate plant, so that around 34 per cent rejected and Fe grade increase from 25 per cent to 33 per cent and by weight recovery 66 per cent. The results of the test work showed that this methodology could decrease largely the impact of dilution in the feed to the plant. It also slightly effect on the reducing of dilution factor impact for open pit design and optimisation and leads to increase the mineable tonnage in the low-grade magnetite iron ore mine.

Aug 24, 2022

By Wenya Du, Qingbo Yu, Peng Li, Qin Qin

"A new heat recovery system is proposed. This system uses the endothermic heat of gasification reaction instead of sensible heat to recover the energy of molten blast furnace slag. The gasification technological parameter in molten blast furnace was calculated and the exergy of the system was analyzed. The gasification reactions were studied kinetically by the isothermal thermogravimetry using STA409PC thermal analyzer. The results showed that, according to different gasification agent, this system can produce syngas with different C-H ratio. The exergy efficiency of this system is high and its internal exergy loss rate is about 11%. This method can bring huge economic and environmental benefits which are important to the survival and sustainable development of iron-steel enterprises. The molten BF slag acts as not only thermal media but also good catalyst. The kinetic parameters on gasification reaction with different types of coal used differ from each other.IntroductionEnergy consumption in the iron-making process is about 50%~60% of the total energy input. The blast furnace is very important in the iron & steel process. So energy conservation and emission reduction about blast furnace is very important. In recent years, in order to recovery energy, many new technologies such as TRT (Top gas pressure Recovery Turbine) and CCPP (Combined Cycle Power Plant) were used in iron-making. But the energy of molten blast furnace (BF) slag has only been used limitedly so far.Molten BF (Blast Furnace) slag is the byproduct of iron-making at the high temperatures range from 1723 to 1923K, and has a large amount of sensible heat remaining. The yield of molten BF slag is about 300 kg per ton of pig iron. In conventional processes, molten BF slag is quenched rapidly using a large amount of water to produce a glassy-granulated slag. The quenching slag must be dried before it can be used in cement manufacture. During the process, a large amount of water was consumed and the energy of molten slag can not be recovered. At the same time, it causes environmental pollution problems. So the critical problems of the process are not only energy recovery of molten slag and reducing emission of H2S and SO2, but also guaranteeing the subsequent use value of slag. For this propose, many new technologies were investigated to recover the thermal energy of molten slag. The promising methods are dry granulation [1-4] and reforming of methane [5-9]. The method, utilization of reaction heat instead of latent heat and sensible heat, is quite attractive from viewpoints of energy storage without heat loss, and makes a connection to other industry. But both of them are in laboratory. In this paper, coal gasification in molten BF slag was used to recover the energy of molten BF slag. The gasification technological parameter in molten BF was calculated and the exergy of the system was analyzed. The gasification reactions were studied kinetically by the isothermal thermogravimetry using STA409PC thermal analyzer."

Jan 1, 2011

By A. Bascetin

Waste materials caused by mining activities are an important environmental problem. Paste technology is a good alternative for waste management because it has many benefits in the aspects of environment, cost and safety. Disposal of process wastes in paste form is an attractive option for waste management, as it eliminates or reduces the risks associated with conventional methods. Due to the geotechnical characteristics of the paste, it is very similar to soil materials. So determining the geotechnical properties of the paste material is essential to durability of the paste. The some important geotechnical properties are compressive strength, porosity, shear strength, hydraulic conductivity, water content, consolidation, etc. In this study, the important parameters and the relation between them were investigated and obtained some results which will affect for optimum design of waste management.

Jan 1, 2012

The Study of Jamesonite Flotation Behaviour

Sep 13, 2010

By Andrey V. Yevdokimov

The results of the test work on gold leaching using high strength of cyanide solution in the presence of activators are presented. The major physical and chemical relationships of gold leaching were determined. Intensive cyanidation results of gravity concentrates with various material compositions using an activator are given. Process design criteria for intensive cyanidation unit were developed on the base of pilot plant test results. Keywords: gold, activators, intensive cyanidation, gravity concentrates

Sep 1, 2012

By S. Tuylu, D. Adiguzel, U. G. Akkaya, A. Bascetin

"One of the main problems for storing of the tailings is acidity occurrence due to several factors such as existence of sulfuric minerals and also the pollution in seepage waters by mobilization of metal ions, which holds great risks in terms of environmental regulations. Because of these specified reasons, tailing materials to be used in a SPD formula should have comply with some specifications. Among these properties; oxygen content, temperature, matrix suction and pH are the most important parameters. In the study, the relationships between the parameters mentioned are investigated to reveal optimum paste design layout. The lowest amount of seepage water obtained from the paste layers in the pilot cabinet was found as 2150 ml from 3rd layer. As for the maximum seepage water and the average of the all 11 layers were found as 4909 ml from 6th layer and 3273 ml respectively. The reactions occurring according to the oxidation, as seen at seepage water of second and third layers, decreased the pH of system to the under of 7 value. Additionally, when the seepage water of first layer’s EC value is 2.93 mS/cm, the EC value of second layer is increased at 3.54 mS/cm. The other parameters are evaluated with the obtained results of the tests to determine the optimum storing conditions for SPD.INTRODUCTION Conventional waste disposal methods, although widely used, pose great environmental risks. One of the most important issues is acid mine drainage (AMD). Tailings of metallic mines contain heavy metals, aggressive chemicals and hazardous materials. In the presence of oxygen and water, an oxidation reaction can occur, causing a decrease in pH of the environment, and heavy metals that are present in the environment can dissolve easily. Subsequently, heavy metals can pollute underground water basins, creating a great amount of danger for the ecology and potable water resources. Another important risk associated with conventional waste disposal methods is accidents related to the waste dam. Higher volumes of water and tailings (usually 15% solids and 85% water by weight) are sent to waste dams, making it very difficult to control the stability of the dam under conditions such as static and dynamic loads (seismic activities, vibrations caused by blasting, etc.), flooding, and seepage. In case of an accident or failure, the spread of great amounts of mud containing hazardous chemicals and heavy metals can harm the environment of the dam site significantly (Bascetin et al., 2014). In the paste technology, depending on the type of ore, tailings used in the paste mixture can contain sulphide minerals (such as pyrite and pyrrhotite). These minerals are known to be reactive with water and oxygen to produce acidity (sulphuric acid)."

Jan 1, 2015

By Dong Liang, Qijie Zhai, Zhichen Zhang, Qixin Li, Zhishuai Xu

"The formation, distribution and survival of pure Al nuclei under surface pulsed magneto oscillation (SPMO) treatment were investigated with thecombination of experiments and numerical simulation. The results indicated that the nuclei originated from the whole top surface of melt owing to the oscillation of top surface induced by SPMO. The temperature field significantly affected the survival of the nuclei The electromagnetic force and flow field of the melt with SPMO treatment were simulated by finite element software ANSYS. The electromagnetic force mainly distributed below the top surface near the mould wall. The electromagnetic farce not only made the melt oscillate but also increased the convection of meh below the top surface vigorously. The oscillation near the top surface of the melt promoted the nucleation largely, and the convection increased the uniform of the temperature distribution in the whole meh which favored the survival of nucleiIntroductionAs we all know, fine equiaxed grains are beneficial fur the improvement of the mechanical property, process ability and the uniformity of metallic materials [1-2]. With the researches of recent decades, people discovered that the electromagnetic field is an efficient method to refine the solidified structure of metals [3-7]. Pulsed magnetic field technology obtains more and more attentions in recent years due to its smaller power consumption, bigger instantaneous magnetic field intensity, non-contacting with the meh and simple convenient equipment manufacturing [8-9]. However, the melts would splash fiercely when pulsed magnetic field is applied with a slightly higher power. Thus, based on the understanding of the solidification refinement mechanism of electric current pulse (ECP) [10], Gong et al [11] developed a novel technology called pulse magneto-oscillation (PMO) to refine the solidification structure. The technology can be easily applied in the solidification structure refinement of continuous casting slab. But fur aluminum continuous casting, the sump is very shallow, which greatly limits the application of pulse magneto-oscillation technology."

Jan 1, 2014

By A. Zarei-Hanzaki, S. M. Fatemi-Varzaneh, M. Haghshenas

The microstructure in modified semi-solid ALTHIX (A356) alloy consists of aAl phase with Al/Si eutectic structure. Silicon phase in eutectic structure is coral like with fine fibers. The lack of good ductility in this alloy is related to the presence of silicon fibers. Accordingly many investigations have been recently conducted to modify the Si morphology through Thermomechanical processing on this alloy. In the present work an ALTHIX (A356) alloy was deformed at 450°C, 500°C and 540°C through different strain rates. Consequently the silicon fibers were broken into small particles. The results indicated that the Si particles may coarsen according to Ostwald ripening mechanism at 540°C deformed by rate of0.0005 sec-1 & 0.0001 sec-1-

Jan 1, 2006

By S. Tuylu, D. Adiguzel, A. Bascetin, H. Eker

"Tailings can be more stable in-site where they are stored and and so the risk of conventional tailings dam accidents can be reduced by alternative methods. In recent years, surface paste disposal (SPD) method is one of the alternative tailings storage methods. According to the results obtained from the previous lab scale experiments, optimum storage design was determined and then, this design was carried out in-site application under atmospheric conditions by a pilot scale tests. In the field study, two separate dams with no environmental hazards were established by the hazardous waste storage directive, whose surface area is measured as 400cm × 200cm. Also physical changes in the paste tailings were measured by the sensors such as volumetric water content, mutric suction and oxygen consumption. In addition, seepage water was collected in the drainage pool and examined for acid mine drainage and metal mobilization risks. As a result of the preliminary data obtained from measurements of pilot scale tests, when the pH value of seepage in the cemented dam (only 1th and 10th layers with cemented) is about 11, the pH value of seepage in the uncemented (reference) dam is measured at 8-9. INTRODUCTION Environmental damages occurred during the deposition of mine process tailings at surface using conventional methods (tailings dam etc.) can be reduced and/or eliminated with the use of new technologies and methods to an important extent. Nowadays, it has been investigated to safely deposit metal mine wastes generally discharged into surface tailings dams, seas, rivers, creeks etc. using Paste Tailing Technology which gains the growing importance in recent years. Meanwhile, Paste Tailings Technology has two applications in industry as an underground paste backfill and surface paste deposition. Particularly scientific studies about deposition of process tailings as paste sample in underground and surface have been increased. These studies showed that surface paste deposition can minimize the free water amount which is the biggest problem in conventional tailings dams. Additionally, it also provides less particle segregation, in other words, the formation of more homogenous material, the development of geotechnical properties which causes to obtain more stable material, increases the strength and stability of the paste with addition of binder where necessary surface paste material, and reduces the risk of Acid Mine Drainage (AMD) (Bascetin et al., 2017a). Theriault et al. (2003), Martin et al. (2006) and Simms et al. (2007) reported that Bulyanhulu mine in Tanzania is the first gold mine to employ surface paste disposal (SPD) worldwide. Here, tailings are deposited alternately via several towers. The tailings flow away from each tower to forming a conical deposit. Each layer had a lower thickness than 30 cm. The fresh tailings were poured on top of drying and hardening layer after a waiting period of 5-30 days. No cement was added into the tailings to prepare paste material. Uncemented paste was deposited by a solid content of 73% which corresponded to a 250 mm slump cone height (Yilmaz et al., 2014). In a study conducted by Yilmaz (2010) illustrates the preliminary results of a field cell testing undertaken to investigate the effect of in situ climate conditions and material properties on the performance and quality of fine-grained, sulphide-rich paste tailings at the LaRonde mine in Quebec, Canada. A total of two field cells are constructed in the surface disposal site of the mine and categorized as cemented cell CC and uncemented cell UC (Bascetin et al., 2017b)."

Jan 1, 2018

By Ximing Yuan, Yongsheng Xu, Hongjie Li

A study of a static demolition agent that can be used underwater has been carried out. A new type of granulated static demolition agent with rapid reaction has been tested in several hundred experiments. It can be used conveniently and simply in the field. It demonstrates a fast reaction rate with high expansion pressures. The important characteristic of the new type of granulated static demolition agent is the ability to function underwater. It will destroy rock and the other brittle material without flyrock, vibration, shock wave, toxic gas or noise. The reaction rate can be controlled within 30-60 minutes. It is difficult to use these products when the reaction rate is less than 30 minutes and it is less efficient when the reaction rate is longer than 60 minutes. The reaction rate is slightly increased after the material is kept in storage for two years. A new type of the hydraulic device that is used to measure the expansion pressure of solid materials has been designed. The expansion pressure of the granulated static demolition agent has been tested with the device. It is shows that the expansion pressure of the granulated static demolition agent can get to 80~120MPa in 60 minutes. Also included is a discussion of the thermodynamics of the static demolition agent.

Jan 1, 2003

By S. Tuylu, D. Adiguzel, A. Bascetin

"In recent years the fact that mining tailings cause serious environmental problems resulted in increasing number of studies about their disposal, storage and usability in various areas. Therefore the new studies about using the tailings for some purposes such as using in shotcrete or producing concrete have been increasing recently. The study is focused on applicability of tailings for producing shotcrete. Under this scope it is considered that mining tailings can bring many advantages in case of that they are used instead of sand, silt or fine aggregate in shotcrete applications. Most important advantages can be listed as decreasing shotcrete cost, decreasing amount if mining tailings to be disposed and the contribution to be provided on sustainable production of sources. The main objective of this study is the investigation of using mine tailing instead of fine aggregate in shotcrete. In this study, 10 shotcrete designs in different proportions were formed, and properties of the mixtures were identified. Then, the experimental results were statistically analyzed, the effects of the amount of the tailing material used on shotcrete properties were presented, and empirical approaches that can be used for the estimation of these properties were developed. INTRODUCTION The disposal of high amount mine tailing on the surface is caused a lot of problems in terms of environmental impact. Unfortunately, it is known that classic disposal techniques such as tailing dam cannot provide a solution these problems. The tailing dams which are usually used in the disposal of mining tailings bring along many problems in terms of cost, environment, and human health. So mine tailings are used in different production such as shotcrete. This technique is becoming increasingly common during recent years. The usability of mine tailings in brick and concrete production instead of cement and fine aggregate has been studied by many studies [1-4]. This situation has been promising for the usability of tailings in shotcrete which is commonly used for ground support especially in tunnels. Shotcrete (sprayed concrete) is applied mainly for construction of tunnels, shafts, renovation works and strengthening of slopes. Main advantage of shotcrete is fast development of strength, which quickly ensures stability of strengthened structure [5]. Shotcrete can be defined as spraying the grout consisting of water, aggregate, cement and optional additive mixture on the desired surface with a compressed air. According to the definition of the American Concrete Institute (ACI), it is the spraying of sprayed grout or concrete on a surface at high speed with air pressure [6]. In recent years, the use of shotcrete for the support of underground excavations is decreased in the mining industry. The design of shotcrete support for underground excavations is a very imprecise process. Strength and pumpability properties of shotcrete are very significant for determining suitable shotcrete design. Flow characteristics of the shotcrete must be determined for pumpability and fluidity of the material."

Jan 1, 2017

By A. V. Byvaltsev

Adsorption of cyanide complexes of gold, silver, copper, mercury, nickel, cobalt, iron, zinc and cadmium has been studied. Adsorption isotherms of the mentioned metals from individual solutions for different free cyanide concentrations have been obtained. Values of the constants of Freundlich isotherm equation have been calculated. Metal cyanide complexes affinity to activated carbon was determined.

Jan 1, 2014

By Xuexin Ding, Weijie Wei, Jinwang Zhang, Yi Chen, Shengli Yang

"Many ultra-thick coal seams exist in Xinjiang and the northern part of the Inner Mongolia. These coal seams are more than 30-40m thick. This kind of the thick coal seam is too difficult to extract in one slice, so the top-coal caving longwall mining method was designed for this purpose. In order to study the movement characteristics of the overburden strata and the development of the ""three zones"" in ultra-thick coal seams, the physical and numerical simulations were carried out based on the in-site condition of Baiyinhua coal mine. The result shows that, when extracting the upper part of the l 5m thick coal seams, the first weighting interval was 50-58m and the periodic weighting interval was I 8-20m. The caving zone, fractured zone and bending and sinking zone were 38m, 92m, and 50m respectively in height. The fractured zone height increased with the advancing distance of the face, but in some localities, a ladder-like distribution due to the periodic weighting existed. When extracting the lower part of the 25m thick coal seams, the roof was extremely broken and the collapse range of overlying strata continued to increase in irregular form.INTRODUCTIONThe thick coal seams occupy 44 percent of coal reserves in China and account for 45 percent of the gross domestic coal production. There are three main methods for extracting the thick coal seams: sublevel mining, large height mining, and longwall top-coal caving (LTCC) (Wang, 2009). Due to the rapid development of LTCC in the past two decades, it has become the most extensively used mining method. It possesses the advantages of high-production, high-efficiency, low development ratio, and low-cost (Yang, Zhang, Chen, and Zhengyang, 2016; Wang and Zhang, 2015). Baiyinhua coal mine's coal reserves are full of uniformly distributed thick coal seams, with the minable thickness of the main coal seam between 25 to 40m, i.e. the main coal seam is an ultra-thick coal seam. Sublevel longwall top-coal caving (SLTCC) which is an efficient method for extracting the ultrathick coal seams has led to multiple disturbances Xie, Chen, and Wang, 1999; Singh and Singh, 1999; Xie, Chang, and Yang, 2009. Therefore, using the case of Baiyinhua coal mine, the movement features of overburden strata and development characteristics of the three zones in ultra-thick coal seams were studied by physical and numerical simulations (Qian, et al, 2003; Qian, 1994)."

Jan 1, 2016

By A. I. Urvanzev, N. V. Shikhov

"In this paper, we present the study’s results of electrical separation processes on the basis of new separator designs, new technological solutions, and newly discovered effects. We considered the options of enrichment by magnet separation of magnetite and titanomagnetite ores, ores and products containing chromium and manganese, ores of non-ferrous and precious metals. During pneumo-electric separation of mixed iron ore of SMPC, 43.3% of the output of the concentrate with an iron content of 61.7% was obtained in one step, with extraction of 70.5%. The paper also presents the results of the finalization on the air-electric separator of the magnetic fraction when separating oxidized ores of MPPOO (mining and processing plant of oxidized ores) on the Jans polygrade magnetic separator. A concentrate was obtained with an iron content of 65.1% with the extraction of 95.0% and tails with an iron content of 13.0%. The possibility of obtaining low-silica concentrates from these ores with an iron content of 67.15 and a quartz of 2.88% is shown. Also, the results of tests on the enrichment of chromite ores on the firing-magnetic scheme with corona-electrostatic separation are considered. On the initial ore of the Don MPP (mining and processing plant), a concentrate with a content of 61.8% Cr2O3 was obtained with a quartz content of ~ 1.0%. The results of pneumo-electric separation with triboelectric charge of the separated particles are presented. The results of the tests indicate a principal possibility of enriching chromite ores without costly high-temperature roasting. Dry technology of enrichment of manganese ores with the use of electrical separation increases the quality of the oxidized concentrate to the first grade and raises the total extraction by 2 times. For the Chineya deposit of titanomagnetite ores with copper impurities, electroseparation operations were carried out on two samples with a Cu content of 1.93 and 3.75%, respectively. For a sample with a Cu content of 6.02%, a copper concentrate output of 24.42% was obtained with a Cu content of 23.82% and the extraction of 94.88%. The results of enrichment by electroseparation of gold-containing sulfide ores can have the practical importance. For ores of the Berezovskoye deposit, a pyritic concentrate containing 100 g / t of gold was obtained after two or three operations of IES (integrated energy systems)."

Jan 1, 2018

By Sydney C. Mifflen

COAL MINING, with its some 15,000 employees, is directly responsible for the livelihood of one-fifth of the population of the Province of Nova Scotia and indirectly so for that of possibly another fifth. Deposits of coal are known and worked in four counties of the Province, from which is being produced yearly tonnages as noted below: Cumberland County 750,000 tons Piccou County 400,000 tons Inverness County 100,000 tons Cape Breton County 5,250,000 tons TOTAL FOR NOVA SCOTIA 6,500,000 tons Production in Cape Breton county is entirely from the one source, the Sydney coalfield, and not only is this field the most important in respect to output, as is disclosed above, but it is also the largest presently known deposit in the Province and holds the greatest tonnage yet in reserve for future mining. In the light of the above more or less generally known facts, it is trite to remark on the importance of the Sydney coalfield in the internal economy of the Province. On the other hand, not nearly as well-known nor as frankly recognized is its significance in the national life of Canada, for from this field is produced not only 80 per cent of the Nova Scotia coal but over 40 per cent of all coal mined in the Dominion. Another noteworthy comparison can be made from the fact that the Sydney field contributes 22 per cent of all the bituminous coal consumed in Canada, the remainder being made up of 7 per cent mined elsewhere in Nova Scotia, 27 per cent from other parts of Canada (British Columbia and Alberta, principally), while the remaining 44 per cent is imported, practically wholly, from the United States of America.

Jan 1, 1941

Subsurface information from the "Upper Coal Measures" of the Sydney Basin is interpreted by means of structure contour maps, isopach maps and geological cross- sections. Particular reference is made to recent coal drilling operations by the New South Wales Department of Mines. The study is restricted to the onshore portion of the Sydney Basin.

Jan 1, 1972