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By F. E. P. PEARSON

Sandstone quarried from an island in Lake Winnipeg is barged 130 km to a processing plant at Selkirk on the Red River. The stone is white, poorly consolidated, and consists of rounded quartz grains of high natural purity. It is an important supplier of silica in Western Canada for glass, fiberglass, foundry and other industrial uses.

Jan 1, 1984

By Si Qin

Unknown goafs and roadways of abandoned coalmines can be a great water inrush hazard for coalmine workers. Consequently, advance detection of such hazards is of great importance. By detonating seismic charges in underground coal seams, we can collect seismic data using a surface survey line, which is located across the ground projection of the underground shot point. This experiment was conducted in a coalmine in Shaanxi Province, China. After surface elevation compensation and travel time adjustments, we accurately determined the position of the goaf boundary along the survey line based on the wave velocity anomaly on the seismic record. Then we used a scattered wave imaging technique to enhance the energy of the scattered waves that are generated when the coal seam roof slide wave (refracted wave when the incident angle bigger than the critical angle) hits the roadway, thus confirming location of a geological discontinuity (roadway). This experiment shows that the coalmine ground seismic method, employing an underground explosive charge and a surface seismic array, has the ability to detect an abandoned roadway and goaf in advance of coal mining, thus can improve worker safety.

Aug 1, 2013

By G. R. Guillet

"Bricks made from local Paleozoic shales, and floor and wall tiles made from imported clays, both established record production volumes in 1985 and are the strongest segments of Ontario's clay products industries. However, renewed interest in traditional materials also supports a good market for clay flower pots and flu e liners, and innovative processing studies are showing promise for possible new production of clay roofing tiles. This paper reviews the highlights of a comprehensive study of Ontario's clay products industries, completed in 1986. IntroductionFor some years now, Ontario's clay products industries have been unspectacular in their attempt to cope with the recent recession and the impact of alternative materials. But a strong demand for bricks in recent years has done much to dispel the gloom. Bricks, drainage tiles, sewer pipes, flue liners, structural and partition tiles, and flower pots have been commonly referred to as ""heavy"" clay products, and they have been based largely on local clays and shales. To this list might be added expanded aggregate and mineral wool. Clay refractories, sanitary ware, electrical porcelain, art pottery, and floor and wall tiles are not considered heavy clay products, and are commonly made from a variety of ceramic materials, many of which are imported.Production facilities for heavy clay products often began in Ontario as small family enterprises, using whatever clay was available locally to supply the local market with building bricks and other clay products needed for construction. Improved road systems increased the market range for these plant s, and new technology and industry standards resulted in gradual upgrading and consolidation of them as traced in Table I"

Jan 1, 1988

By T. Loos

The Norddeutsche Affinerie operates an Outokumpu-Flash-Furnace as a smelting unit. The pyrometallurgical slag cleaning process is based on the slag reduction and settling in the electric furnace. Since 1972 when the slag cleaning furnace was built the throughput could be increased fourfold. However, an extensive optimisation effort is required in order to keep the copper loss low. A parameter study with a neuronal network model based on real process data was conducted to identify parameters impacting on the copper loss in the slag. It could be demonstrated that the main parameters responsible for copper loss in the final slag are fixed parameters of the flash furnace. For a better understanding of the copper loss in the electric furnace microscopic analyses of the slag structure and viscosity measurements were performed. Based on these results the reduction and settling of the copper containing droplets could be increased in both pilot plant studies and industrial scale. 4

Jan 1, 2007

By M. Oliazadeh

The bioleaching of fine low grade copper sulfide ore is described. A sample of ground (> 1 mm) copper ore from Sarcheshmeh, Iran, was subjected to a series of agglomeration procedures and subsequently leached. The best agglomerate was obtained by using lime and sulfuric acid as binders. A column bioleaching test of agglomerated ore was then run for 105 days along with a non-inoculated control column having thymol as bactericide. The results show that about 77.5% of copper was extracted in the bioleaching, whereas the control column achieved only 57% copper leaching.

Jan 1, 2007

By T. Kawai

Japan Oil, Gas and Metals National Corporation (JOGMEC) has started an exploration program for Seafloor Massive Sulfides (SMS) in the EEZ of Japan, and launched an investigation program for mining, processing and environmental impact on SMS development. With regard to the mining aspect, the mining system consists of three units: a mining unit on the sea floor, an ore lift-up unit to surface, and a mining support vessel unit which has an ore unloading system that unloads onto a shuttle ship. Regarding the mining unit, JOGMEC and certain Japanese mining and machinery companies developed two types of state of the art mining testing tools. Excavation tests on the actual SMS site in the Okinawa Trough, south-west of Japan, were conducted in 2012. In these tests, the functions of the testing tools, such as cutting ore, moving on the seafloor and climbing up slopes having steeper than a 25 degree gradient, were confirmed. The physical characteristics of the ore, which are key parameters for establishing a mining system, are yet to be fully understood as the exploration program has been undertaken simultaneously. Hence, those examinations have been carried out by ground cutting experiments, analysis of drilling core data, and the like. This paper describes the outline of a proposed mining system, mining testing tools and results of the on-site mining testing.

Aug 1, 2013

By Andrew Cormier

"The Early YearsThe Grand Lake coal fields in New Brunswick undoubtedly can claim the distinction of being the first part of North America from which coal was mined and exported. The diaries of the Governor of Massachusetts during the first half of the 17th century clearly establish this fact. There is also a reference in the Massachusetts Colonial Records which indicate that coal exports to New England were carried on as early as 1639.It has generally been believed that Cape Breton mined and exported the first coal; but no account has yet been found to show that this took place earlier than 1676. Both at Grand Lake and Cape Breton the coal was near the surface and removed by hand.When the country passed entirely into British control, Joseph Garrison, a grantee of Maugerville in 1765 moved to Jemseg. While surveying the north side of Grand Lake he discovered outcroppings of coal on the shore of the lake and further inland along the banks of streams. It was he who named Newcastle Creek in reference to Newcastle in England, which was widely known for its coal mines. Joseph Garrison died in 1783, the same year that an influx of United Empire Loyalists increased settlement in Newcastle Creek in the area now known as Minto. Many Loyalists also settled on the shores on both sides of Grand Lake.At a number of points where streams cut channels through the overlying strata, the coal seams were exposed and it was at such outcroppings that the early operations were carried on. A tunnel was driven in the seam from the foot of the bank, affording both an outlet for the coal and natural drainage from the workings. The coal was loaded into boxes and wheeled over wooden tracks to a point on the surface where it could be dumped into wagons and hauled either direct to destination or to where it could be loaded into boats and conveyed via Grand Lake, Jemseg and Saint John river to points of distribution.In the latter part of the 18th century and first years of the 19th century, farmers were undisturbed by mining the coal found on their lands. This was soon to change and resulted in many years of contention between landowners and the Legislative Assembly.New Brunswick became a separate province from Nova Scotia in 1784 and the seat of government moved from Saint John to Fredericton in 1788. The new province had its first priorities; the establishment of counties, the building of roads, and the development of its natural resources. From 1805, records of coal and land development are fairly complete. These records show the increasing interest of the Province in developing the coal fields. This interest resulted in the granting of coal leases to many friends of the government, without any regard for the wishes of the farmers who owned and had occupied the land for many years. The farmers fought back with lawsuits and other forms of dissension but with little success. By the end of the 19th century there were very few farm operators left in the area."

Jan 1, 1992

By N. Djilali

Many of the transport phenomena encountered in proton exchange membrane fuel cells occur intrinsically at the microscale level. Physically representative models that fully account for the salient physico-chemical and transport processes in PEM fuel cells are necessary to achieve truly predictive models that can be used with confidence to: (i) gain a better understanding of in-situ processes and couplings, (ii) explore new concepts, and (iii) support design and optimization. The development of more general, rationally based macroscale models requires use of knowledge on the microscale level to provide guidance, and to determine the required parameters and coefficients (model "constants"). In this paper we present a new membrane transport model, the binary friction membrane model (BFM2), recently developed to account for coupled protonic and water transport in polymer membranes. This general model is based on rational and physical consideration, removes several of the limitations of the empirical models used to date, and is formulated for all purfluoro-sulfonic acid membranes. The use of the BFM2 in a fuel cell model is illustrated highlighting significant performance predictions compared to existing empirical model. The second part of the paper addresses the fundamentals of two-phase transport in hydrophobic gad diffusion media. Computational and experimental visualizations resolving the microscale dynamics of water transport between the fibres of a GDL are presented, revealing transport mechanisms that are, contrary to assumptions used to date, dominated by fingering and channeling.

Jan 1, 2005

By G. Riveros

A new, continuous fire refining process for copper has been developed and tested at the 5 tph pilot scale. During oxidation, the blister copper flows through a packed bed of crushed refractory bricks counter-current to a hot oxygen containing gas. The resulting desulphurized copper flows then directly into a packed bed of charcoal for deoxidation. By controlling the air to natural gas ratio, both temperature and reducing conditions can be controlled. Based on extensive laboratory scale measurements of the rate of copper oxidation and reduction, the process concept was developed aided by process modeling and simulation. The industrial-pilot scale installation built at the ENAMI Paipote smelter in Chile, consists of two cylindrical, compact reactors, operating in line, with a designed capacity of 5 t/h of blister copper. The results of the industrial-pilot tests confirmed the feasibility of the new process. The blister copper processing capacity was increased to 10 t/h with satisfactory sulphur removal. The degree of oxidation as well the copper temperature was controlled with relative ease. The specially designed siphon block allowed for smooth tapping of the oxidized copper and separation of refining slag. The reduction of oxidized copper in the packed bed of charcoal appeared to be very effective while control of the degree of reduction according to the height of the bed ensured control of the oxygen content in the refined copper at the required level.

Jan 1, 2007

By R. Kaibyshev, I. Zuiko

"The effect of thermomechanical processing (TMP) including cold working by tension or rolling before aging on mechanical properties and a dispersion of secondary phase particles of an AA2519 alloy (Al–5.64Cu–0.33Mn–0.23Mg–0.15Zr–0.11Ti–0.09V–0.08Fe–0.01Si (wt. %)) was examined. It was shown that the use of tension to impart pre-strain =10% in the alloy provides the best combination of properties in peak aging condition of the material. The AA2519T87 alloy processed by tension exhibits the yield stress, ultimate tensile strength and elongation to failure of 425.4±2.4, 475±2.4, 12.1±0.4, respectively. The one pass rolling leads to -5% decreases in yield stress and –20% decreases in ductility. Dislocations serve as heterogeneous nucleation sites for ?'-phase precipitation. The positive effect of tension is attributed to the formation of more homogeneous dislocation structure, uniform distribution of ?'-phase particles with higher aspect ratio. Precipitation of the O–phase plates on {111}a habit plane was detected. In addition it was shown that the low angle boundaries are heterogeneous nucleation sites for ?' and O particles.INTRODUCTION Precipitation-hardened alloys are a commercially important group of the materials because their mechanical properties can be modified by treating and changing the microstructure. Age-hardenable aluminum alloys belonging to the Al–Cu–Mg system are widely used due to their attractive combination of high specific strength, good fracture toughness and enhanced creep resistance attributed to the highly efficient strengthening by the ?'-phase (Palmer, StJohn, Nie, & Qian, 2017). An AA2519 alloy exhibiting superior mechanical properties among high-strength Al–Cu alloys (2XXX-serie) due to minor Mg additives. It is known that, in alloys with high Cu/Mg ratio (=5.6) the classic precipitation sequence (Palmer et al., 2017; Wang & Starink, 2005; Wang et al., 2010) of supersaturated solid solution (SSSS) decomposition occurs: SSSS ? GP zones (Al3Cu) ? ?? (Al3Cu) ? ?' (Al2Cu) ? ? (Al2Cu) (1)"

Jan 1, 2018

By A. Vervoort

The concepts of geostatistics are commonly difficult to understand for students, even for those with a strong mathematical background. A main problem is certainly the link between the variation of the parameter value in space or time, and the calculated experimental semivariogram as a function of the interdistance, but over the entire area. Another problem is to differentiate between directional and omnidirectional semivariograms and the way they have to be interpreted. Furthermore first time users of geostatistics often do not want to struggle through different books with the whole geostatistical background before using it. Too often this leads to using geostatistics as a black box with all the risks linked to it. That is the main reason that we developed some interactive tools based on the free public domain software R. We aim by developing three different modules to assist individual first time users, but also regular students and teachers to get a feeling of the importance of the various aspects in conducting a good geostatistical study. The modules show directly e.g. the impact of deleting, moving or adding data points, of changing parameters of the semivariogram model and of the geometrical parameters during kriging. The first module allows making the link between the variation of the parameter values in one direction and the calculated experimental semivariogram, and this for different given datasets. The second module covers two dimensional datasets and apart from calculating the semivariogram values, models can be fitted to the calculated data. A distinction can be made between omni-directional and directional semivariograms, including the effect of the tolerance on the angle and lag-distance. The third module focuses on ordinary kriging of point values in two dimensions. The aim of the interactive tools developed is limited to educational purposes only, i.e. to visualize some basic concepts for different pre-selected types of spatial variation. They do not intend to do a geostatistical study on a certain dataset (for this purpose there exists already a broad spectrum of good software packages). The original intention of developing the three modules was aimed at users with no or a limited amount of geostatistical experience. However, these modules seem also very useful to remain critical for experienced users. One should never forget that in a real application one does not have a complete view of the phenomenon studied. The geostatistical interactive modules can be accessed through: www.bwk.kuleuven.be/geostatistics . We compiled a manual to facilitate the use of the modules and to guide the user we formulated several questions to be solved for each module.

Aug 1, 2013

By V. Panayotov, M. Panayotova

"Finding a reliable relationship between fundamental properties of minerals of non-ferrous metals and their ability to float is extremely important. The approach presented in this work allows us to draw predictive models for an effective flotation, suitable choice of reagents regime and expected technological results before the minerals enter the flotation process. Attempts to adjust the technological regime in already begun flotation are often unsuccessful because the basic physicochemical processes have already taken place. Mineral processing can be optimized on the basis of objective and basic parameters, decisive for the efficiency of the process - the state of the surface of the mineral; assessment of: minerals flotation ability, the need to apply and the type of needed pretreatment, and expected technological results. The theoretical foundations of such an approach are presented in the work, as well as supporting them experimental results, and information on practical implementation in lead-zinc and copper-pyrite ores selection.INTRODUCTIONIncreasing impoverishment of ores of nonferrous metals incoming to the flotation and rising costs for obtaining the final product lead to the inevitable question - will the mineral processing process be beneficial economically, technologically feasible and environmentally safe and what is the way to improve its efficiency. Some of the possible solutions are already in practice - new more efficient and less energy consuming flotation machines and equipment, new - more efficient and selective reagents, new combinations of flotation regimens, and so on.Finding a reliable relationship between fundamental properties of minerals of non-ferrous metals (sulphides and oxides - most of them with semiconductor properties) and their ability to float is extremely important. This is the subject of research, started in the 60s of the previous century and continuing to the present day. Such dependence would enable a realistic assessment of flotation ability (flotability) of minerals before their flotation processing. The basic dependence, displayed by the researchers as Hoberg (1975), Chanturia and Shafeev (1977), Chanturia and Lunin (1983), etc., represents a relationship between bulk properties of minerals and their flotability, considering especially the concentration of the main charge carriers, namely electrons or holes. The bulk properties are practically constant for minerals from a given field. But the 'main arena' of the flotation process is actually the mineral surface (Carta, 1970; Rao, Labonte, & Finch, 1992; Panayotov, 1999; Rao, 2003; Hu, Sun & Wang, 2010). Therefore, we introduce a methodology for studying the surface of minerals, which methodology gives the degree of semiconductor bands bending on the surface and respectively - the charge of the mineral surface and its ability to interact with reagent-collector. The latter can be used to select the most optimal reagent for the corresponding mineral."

Jan 1, 2016

By B. Das

"Computers have been used extensively in the mineral industry in exploration, reserves calculation, mining technology, mineral processing, etc. With respect to coal mining, there are also various applications for evaluating rock slope stability of open pits, design of open pits, underground operations, mine ventilation, ground control, data processing and management information, operations control and certain technological applications. Mine ventilation appears to be the field in underground coal mining touched on most; on the other hand, underground coal mining methods evaluation is represented only sparingly.It is therefore essential to review the status of the computer in underground coal mining methods evaluation in order to define its scope for further application. The paper discusses the roles of the mining engineer, programmer, computer operator and analyst as well as that of the computer. The important parameters will be identified and discussed along with their application for different underground coal mining methods, with their individual unit processes. Mainly, longwall face operations have been covered. Although many models have been of academic interest, they can be considered as important steps in a transition stage which will be followed by more practical applications for computers for underground coal mining method evaluations in the future. This calls for a coordinated effort from all concerned."

Jan 1, 1981

By Zorigtkhuu Davaanyam, Fisher Wang, Bern Klein, Amit Kumar

"The High Pressure Grinding Roll (HPGR) is an increasingly popular energy efficient solution for comminution of competent ore deposits that primarily competes with conventional crushers and tumbling mills. A significant barrier to increased adoption of HPGRs is the requirement for large amounts (one tonne or more) of sample for pilot testing which may not be feasible for most early staged projects.Various researchers have worked towards developing piston-die and JK drop weight tests to model and predict the energy requirements for an HPGR. Two small scale laboratory test procedures (the SMC test (Morrell, 2009) and the piston press tests (Davaanyam, 2015)) have been developed in recent years to provide necessary information to size an HPGR.These two methods were used to estimate the required specific energy for an HPGR unit and compared to HPGR pilot scale test results from a copper deposit. The comparison provides insight into the benefits and limitations of these tests.INTRODUCTIONHigh pressure grinding rolls (HPGR) have gained popularity in recent years because of their energy efficiency in comminution. Various researchers have suggested that approximately 50–80% of the total energy consumed in a mineral processing plant is used by the comminution equipment (Haque, 1999; Abouzeid & Fuerstenau, 2009; Wang, 2013). Haque (1999) showed that the efficiency of grinding equipment can be as low as 1%. Due to the energy intensive nature of comminution, mining industry has been forced to explore alternative energy efficient processes.An HPGR based circuit has been shown to be 10–25% more energy efficient than a conventional SABC circuit (Von Michaelis, 2009; Wang, 2013). A significant barrier to the increased adaptation of HPGRs is the requirement for a large amount of sample for pilot testing (up to 5 tons), even on a prefeasibility level. Numerous studies have been performed to utilize piston press test to analyze the performance of the HPGR circuit and to predict the energy consumption for an industrial application. This paper uses two small scale laboratory test procedures, the SMC test and a piston press test, to compare the energy requirement to the pilot HPGR data."

Jan 1, 2016

By T. G. Joseph

ABSTRACT: The Canadian oil sands provide some of the harshest mining conditions in the world. Asoperations demand ever bigger tools, the toll on large mobile mining equipment is high, with structural life often half of that expected. Soft ground conditions predominantly lead to fatigue failure scenarios, poor stability, and inconsistent payload evaluations. These challenges are not solely a concern for Canadian oil sands mines; there are far-reaching implications for surface mining equipment in any poor ground-operating environment. This paper focuses on the basics of payload evaluation, motion response, and a simple estimate of structural life for haulers.

Jan 1, 2011

By E. P. Evoy, A. W. Jolliffe

"The Uranium deposit of Gunnar Mines, Limited, is on the south shore of Crackingstone peninsula in the Beaverlodge area of northern Saskatchewan.The ore consists of disseminated pitchblende and uranophane in brecciated syenite, and forms a tubular or pipelike body, outcropping at the surface and plunging southward at about 45 degrees for a known length of1,400 feet (see Figure I). The upper portion is being removed by open-pit mining to a depth of 300 feet below adjacent Lake Athabasca. The remainder will require underground mining methods (see Figure 2).The property was staked in July, I 952, and the orebody was subsequently defined by about 70,000 feet of diamond drilling. A 1,250-ton mill was completed in 1955, and production commenced in September of that year with ore from the open-pit operation. The mill is presently being increased to 1,650 tons capacity, and a three-compartment vertical shaft is being sunk to 1,250 feet in preparation for underground mining.GeologyThe mine property is underlain by an assemblage of Precambrian metasediments known locally as paragneiss, granite-gneiss, and syenite. These lie on the southeast limb of a southwest-plunging anticline, strike about north 75 degrees east, and dip southward at about 45 degrees. Para- gneiss outcrops in the northwestern half of the claim group, and again on the islands south of St. Mary's Channel. The granite-gneiss lies conform-ably within the paragneiss and makes up the southeastern part of the property. The syenite forms an irregular, triangular-shaped mass within, and near the footwall of, the granite-gneiss band. Small lenticular bodies of mafic rocks are also present, the former being most prevalent in the paragneiss.The granite-gneiss is coarse to medium-grained, pink to grey, well foliated, and composed of feldspar (65 per cent), quartz (20 per cent), chlorite, and minor mica. The general concordance of its contacts with paragneiss and the absence of intrusive relationships along these, the presence of uniformly oriented inclusions of obviously sedimentary origin within the granite-gneiss, and the variation in colour and texture across the strike all strongly suggest that this member represents a granitized sedimentary rock."

Jan 1, 1949

By Bhawani Singh, Mahendra Singh, N. K. C Samadhiya

"Inherently anisotropic rocks occur in abundance at many rock engineering project sites in Himalayan region. These rocks pose difficulty in analysis and design due to their direction dependent strength behaviour. Moreover the strength varies in a non-linear manner with confining pressure. Mohr- Coulomb strength criterion is widely used by geotechnical engineers for defining strength of rocks subjected to given confining pressure. However, the conventional Mohr-Coulomb (MC) criterion suffers from the limitation that the strength is treated to be linearly dependent on confining pressure. In the present article, the MC criterion has been modified by incorporating non-linear term while retaining the original parameters c and ?. The non-linearity with confining stress level has been imbibed through critical state concept (Barton, 1976). The criterion has been applied to a triaxial test data base comprising of more than 1140 triaxial tests conducted world-wide on anisotropic rocks. Statistical evaluation of the goodness of fit of the proposed criterion to the data-base has been carried out. Further the predictive capabilities have been evaluated by determining the error in estimation of triaxial strength if only few triaxial test data are available for determining the criterion parameters. The data base has also been back-analysed to assess the critical confining pressure for anisotropic rocks. Statistically the critical confining pressure, for the present criterion, may be taken nearly equal to 1.25?cmax, where ?cmax is the maximum value of the UCS out of all orientations of planes of anisotropy. It is concluded that reasonably good estimates of the anisotropic strength are possible through the proposed criterion.INTRODUCTIONMany rocks encountered in Himalayan region like shale, slate, schist and phyllite are inherently anisotropic and exhibit direction dependency in their strength behaviour. In addition, the strength of the rock also depends on the confining pressure and, the strength response is non-linear especially when the confining pressure may vary over large range. Conventionally, Mohr-Coulomb criterion is the most widely used criterion for rocks. However, the limitation of this criterion in its present form is that the strength is treated to be linearly dependent on the confining pressure. The present study attempts to address the following two main objectives: i) Include nonlinear response in the Mohr-Coulomb criterion while retaining parameters c and In their original form; and ii) consider anisotropic response of the rock for a given confining pressure. A nonlinear strength criterion, which uses shear strength parameters c and as per Mohr-Coulomb criterion, has been suggested based on critical state concept for rocks."

Jan 1, 2015

By Dennis Martin

What is Borehole Hoisting Borehole Hoisting is the use of a hoisting plant to hoist rock, workers and materials or both, vertically through a borehole, between a mine level and surface or between two levels of an underground mine. Screen and bolt ground support on walls of 5.5 m diameter borehole hoisting shaft

May 1, 2013

By Victor Rudenno

"Previous methods have employed statistical analysis to model future mineral resources. The method presented in this paper uses Zipj's Law to determine the size and grade of tin deposits still to be discovered. The law is applied independently to both known deposit tonnage and grades. A probability distribution for both 'tonnage and grade is computed/or those deposits still to be located and then, by applying a correlation between tonnage and grade, a distribution of the probability of metal content discovery is obtained.By considering an economic cut-off in metal contained in a deposit, the probability of economic success for the next tin discovery is computed, both for a world discovery and for the special case of Tasmania, Australia. The results indicate a probability of 11-37% on a world-wide basis and 18% chance of economic success in Tasmania.IntroductionIn the past , most attempts to determine the probability of success in finding an economic mineral deposit have relied on the accumulation of statistical data. These data are then used to predict a suitable frequency distribution to assess the probability of finding a deposit of a given size and grade (Singer,1975).The method not only relies on one having sufficient data, but also on the assumption that the data are not biased and that the distribution (usually log-normal) is a correct one. The method presented in this paper, to analyze tin deposits, uses Zipf's Law, which has been recently applied to oil, uranium, lead-zinc and gold deposits by Folinsbee (1977) and to Western Australian gold deposits by Rowlands and Sampey (1977). Tapp and Koniuszko (1978) have applied Zipf's Law to mineral distribution patterns in the Northern Australian orogenic provinces, which has enabled them to make predictions with a relatively small data source."

Jan 1, 1981

By Feng Tianran, Lu Shijie, Shen Zhengchang, Han Zhibin, Tan Ming

"As a kind of non-metallic material, high-purify quartz sand has been widely used in many fields. Flotation is a popular way to process quartz sand. But it is in difficult position for flotation to get high-purify quartz product due to large amount of coarse particles contained in the feed. In this paper, a design principle of special flotation cell for high-purify quartz sand has been put forward base on ore property analysis and laboratory test, and the pilot scale special flotation cell has been developed to meet the requirement of the quartz sand flotation process. The special flotation cell for high-purify quartz sand is featured by middle positioned impeller, false bottom and draft tube, which could decrease the rising distance of mineralized bubble and strengthen the circulation capacity of the lower part of the flotation cell. Hydrodynamic study indicates that high air dispersion degree and strong lower slurry circulation could be produced by pilot scale special flotation cell, which is helpful to create a suitable hydrodynamic environment for quartz sand processing.INTRODUCTIONNatural quartz is a non-metallic mineral, which is widely used as raw material in multiple industry process (Shifu, 2006). High purity quartz, especially containing more than 99.9% silicon dioxide, is characterized by high temperature resistance, small thermal expansion coefficient, highly insulating and so on. The demand of high purity quartz has been rising along with social and economic development, now high purity quartz is widely used in the field of photovoltaic industry, electronic information, communications and aerospace industry.Quartz is a kind of main rocking-forming minerals in the nature. There are seven genetic types, such as natural crystal, quartz sandstone, quartzite, vein quartz, konilite, natural siliceous sand, granite quartz (Baolei, Shuilin, & Dianchao, 2012). The natural crystal is primarily used as raw material to refine high purity quartz, but it is not available for two reasons. On the one hand, the natural crystal is extremely expensive and poor in resources reserves, which can not satisfy the need of large-scale industrial production. On the other hand, the chemical component of natural crystal is instability, it may lead to low stable product performance in large industrial applications, and it is also difficult to achieve raw materials standardization. Therefore, there are a lot of studies to search for other technological methods to obtain high purity quartz from other genetic quartz types."

Jan 1, 2016