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By J. Z. Yuan

The purity of rectorite is only about 70% after preliminary mineral processing, which has limited its application. In this research, different pulp densities, different dispersants, different dispersing methods and purification flow sheets were used to purify rectorite. The results show that it is possible to obtain high pure rectorite clay with the purity above 90% and concentrate yield between 24.9% and 29.4% by the purification process with composite dispersants, stirred mill grinding dispersion and so on. The obtained high pure rectorite can be further used in rectorite nanocomposites.

Jan 1, 2014

By Robin J. Batterham

The Bologna Process started in 1999 with a declaration signed by ministers from most European countries. As of 2012, the Bologna Process now has 47 participating countries (EHEA 2012). Overall, the Bologna process has demonstrably changed higher education in many countries to allow for considerably more flexibility in course offerings. Keywords: bologna model, education

Sep 1, 2012

By G. G. Xiong

Water-sealed cyclone is a new efficient equipment to use for grading,concentrating of slurry, it was researched and developed by the Kunming Metallurgy Research Institute in the 1980s , and ac-cessed to the 1990 national invention award and the national patent products (ZL02245313.X ). The equipment and technology are innovative, firstly, we design a set of micro-pressure (0.005~0.008MPa) water-sealed device, which eliminates the gas phase of three-phase of sol-id-liquid-gas of the traditional general hydrocyclone grading process, it only has solid and liquid phases. Secondly, the axial velocity envelope surface which is a factor of controlling the accuracy of grading changes to a wedge rotation; and the interface of upward flow to down flow changes from surface to the solid, it can improve grading accuracy. Thirdly, water-sealed box and catheter devices make the stilling which pass through the cyclone cone centrifugal force fields re-enter the pressure grading zone of catheter. The three innovations make water-sealed cyclone can reduce the loss of overflow and has less mud in stilling product. Because the excellent performance, the water-sealed cyclone has application in non-ferrous metals, ferrous metals, non-metallic and aluminum hydroxide industries for grading, desliming and concentrating since it has successfully developed.

Jan 1, 2014

By Linghu Changjin

Based on the characteristics of typical marine sedimentary phosphate rock in Guizhou, Southwest China, together with the research findings made on the surface electric properties of pure collophanites taken from different areas in pure water and under the action of collectors, a pure minerals flotation test of collophanite was conducted in this research. The differences of collophanite flotation behavior and the effects of the different pH values, varieties, and dosage of collector on flotation separation of collophanite were studied. It is suggested that that in pure water, collophanite had a negative charge within a wide pH range. The electro negativity values of collophanite increased with the addition of collectors GJBW and WF-01. When GJBW and WF-01 were used as collectors, the collophanite was depressed in acid medium, but had a good flotability in basic medium.

Sep 1, 2012

By F. H. Wang

The Yinmao Lead-Zinc Mine Co. Ltd. has got 50 years of mining history. In recent years, the manganese grade in the flotation tailings has been continuously increasing. In order to make fuller use of the existing resources, as well as to increase the company?s economic efficiency, our company adopted the technique ?magnetic separation? and ?iron removal? to effectively recycle the manganese concentrate resources.

Jan 1, 2014

By Yuexin Han, Jie Liu, Shuai Yuan, Yanjun Li

"In order to improve recovery efficiency of iron minerals from iron ore tailings and to reduce its connected environmental pollution, this article investigated the reducing roasting of iron ore tailing in a laboratory fluidized magnetization roasting reactor to optimize the roasting method and conditions. The examined parameters included roasting temperature, roasting time and reducing atmosphere. The parameters evaluating magnetizing roast efficiency and theoretical value were determined. X-ray diffraction (XRD) analysis was used to investigate the conversion of iron phase after roasting. The results show that the best magnetizing roast conditions are roasting temperature of 540?, holding time of 15min, and CO concentration of 20%. The magnetization conversion ratio of roasting products is over 80%, under the best magnetic separation condition, the concentrate grade of iron is 65.61 % and the recovery of iron is 83.77 %. The XRD analysis shows that Fe exists in hematite and siderite before roasting and exists in magnetite after roasting. The technique not only recovers the iron minerals from tailings with good economic benefit, but also reduces the environmental pollution of tailings accumulation.INTRODUCTION Iron ore tailings are the solid wastes generated during the beneficiation process of iron ore concentration and are one of the main pollution concerns in the mining industry (Das et al., 1996). Continuous development of the iron and steel industry has led to the increasing amount of iron ore tailings; there are over 300 million tons of iron ore tailings discharged per year (Rao et al., 2016). The huge amount of stockpiled iron ore tailings brings a series of environmental and social problems. Comprehensive utilization of iron ore tailings can not only reduce environmental load but also conserve resources, promoting sustainable development of the society. In recent years, iron ore tailings as secondary resources have received considerable attention in many countries in the word and numbers of studies on utilization of iron ore tailings were carried out, such as recycling the valuable minerals (Datta et al., 1996; Jia et al., 2013; Panda et al., 2018), used in construction material compositions as alternative source of raw materials (Das et al., 2012; Zhou et al., 2012; Luo et al., 2016) and other utilization. The iron minerals were recovery by magnetization roasting (Rao et al., 2016; Yang et al., 2013; Yang et al., 2011) and flotation (Kumar and Mandre, 2016). By comparison the reduction roasting has more advantages, but it was found that the conventional roasting equipment was inefficient, high energy consumption and un-economically applied on an industrial-scale."

Jan 1, 2018

Systemic process mineralogy study on Baerbulawu refractory hematite ore in Kazakhstan has been carried out. The ore contains Fe 41.34%, and 87.26 % of which exists in hematite. Most hema-tite occurs as fine or ultrafine grains and its average size is only 0.015mm. The gangue is mainly composed of quartz, mica, chlorite, kaolinite and other clay minerals. The liberation of hematite is only 66% when the ore is grinded to 75% ?0.074mm, while part of gangue is already liberated from hematite under this grinding condition, so these gangue can be cast away by magnetic separation in advance. Hematite will not liberate completely from gangue untill grinding fineness reaches 86% ?0.038mm, at the same time, free particles of ultrafine hematite tend to coagulate randomly with quartz and clay minerals, so appropriate dispersant is necessary to pre-vent hematite and clay minerals from coagulation. Based on the process mineralogy research, final technology flowsheet is high-intensity magnetic separation by coarse grinding?rough magnetic concentrate regrinding?inverse flotation, and an ideal index is achieved. The yield of final iron concentrate is 43.46%, and its grade and recovery are 66.76% and 70.55% respectively. The research result is also useful to other similar iron ores.

Jan 1, 2014

Compressive crushing is applied in crushing plants used in mineral, mining, and aggregate in-dustry for fragmentation of rock materials. From a global perspective, the total volume of crushed rock is massive and corresponds to several billion tons. All societies have to fulfil a daily need of rock material products and its derivatives such as metals and minerals. The business for metals and minerals is global while the aggregates production is mainly a local industry. This paper presents a broader overview of optimisation with respect to product yield, use of natural resources and energy consumption. High level plant optimisation of compressive crushing plants is covered as well as real-time optimisation and optimisation of single production units. Each of three optimisation areas are presented and a discussion around how these three areas will be able to communicate with each other is given. Several models, e.g. process performance behav-iour with respect to wear, as well as fitness functions can be common for all three areas. Well-defined and representative fitness functions are of the utmost importance in order to assure that the optimisation results reflect the production targets. It is concluded that great benefits can be achieved by linking together different areas of optimisa-tion. The future for compressing crushing lies, without a doubt, in tailored processes both with re-spect to machines optimised for each customer, plant parameters and operation routines as well as an on-line adjustment, which takes into account current information and control possibilities.

Jan 1, 2014

By H. D. Mendoza, M. J. C. Zerna

This study aims to determine the stability of Philippine nickel laterite ore by investigating the behavior of fine minerals of silica (dave=1.514 µm), hematite (dave= 0 1.351 µm), and nickel oxide (dave=1.426 µm) and their mixed-components in dilute aqueous suspension as a function of pH and electrolyte concentration. The zeta- potentials of the minerals are measured and stabilities of different component systems in aqueous suspension are determined. Hamaker constants of the minerals in aqueous medium are derived by getting their respective critical coagulation concentrations (c.c.c.) at stable pH conditions and at various concentrations of KNO3. The iso-electric points (i.e.p) for silica, hematite, and nickel oxide particles are at pH 2, pH 7.5, and pH 8.5, respectively. The stability behaviors of component systems are as follows: a) Silica dispersion is stable at pH range 3-11and unstable at pH 2; b) Hematite dispersion is stable at pH 2-5 and pH 8-11, and unstable near pH 7; c) Nickel oxide dispersion is stable at pH range 10-11 and unstable at pH 3-9; d) Hematite-silica dispersion is stable at pH range 6-11 and unstable at pH range 3-5; e) Hematite-nickel oxide dispersion is slightly stable at pH range 3-4 and unstable at pH range 5-11; f) Silica-nickel oxide dispersion is stable at pH range 10-11 and unstable at pH range 3-9; and, g) Hematite-silica-nickel oxide dispersion is stable at pH range 10-11 and unstable at pH range 3-9. The stability of nickel laterite ore is similar to that of the three-component system in an aqueous environment. The stability tests are analyzed using the classical DLVO theory. The stability conditions in an aqueous environment are essential in developing the appropriate process flow for the separation/ recovery of nickel laterite mineral components and also in the treatment of nickel laterite -laden wastewaters.

Jan 1, 2018

By M. Saghaeian, R. Hejazi, H. Abedini

Vertical ring and Pulsating Wet High Intensity Magnetic Separator (VP-WHIMS) is widely used for week magnetic mineral beneficiation or ferrous impurity removal from non-metallic minerals. Because of the complexity of this machine, mathematical modelling of its process is complicated and time consuming. In this paper, artificial neural network (ANN) and response surface methodology (RSM) were applied to evaluate the VP-WHIMS performance and optimize its main operating parameters in beneficiating of the Chadormalu hematite sample. The operational parameters of this magnetic separator are considered as: magnetic field intensity (2500-8500 gauss), pulsating frequency (20-100 %max), ring rotation speed (0.6-4.6 r/min) and slurry concentration (15-35 w/w %). Concentrate grade and recoveries (weight and Fe) are monitored as responses. Centre composite design (CCD) was used for experimental study. Four process variables were set using small CCD. Eight star points (a=±1), eight axial points (a=±2) and five replicates at the centre point (a=0) were chosen as experimental points. In ANN system, the best network topology was obtained as (4-5-3). The weights connection and biases were obtained using batch back propagation (BBP) method for 21 experimental data points. The results indicate that ANN

Jan 1, 2014

The quality of iron ore fines in terms of high iron content and low levels of deleterious impurities such as Silica, Alumina, Sulphur and Phosphorous is a critical parameter, in sintering and subsequent iron and steel making processes. As the higher-grade ores become depleted, there will be a stronger focus on treating lower-grade haematite/goethite ores and developing suitable beneficiation techniques to reduce the levels of impurities. Innovative flow sheets, based on new and commercially available technologies, is required. These will be needed to include gravity concentration devices, which can handle coarse and fine feed sizes. In this paper, efforts made to reduce the silica and alumina content of a low grade iron ore fines (<1.0 mm size) sample from the Pilbara region in Western Australia are described. The feed sample, a goethite abundant lower grade iron ore fines, which was a plant reject assaying 48.66% Fe with 13.61% SiO2and 5.09% Al2O3 was investigated. To this end, an experimental campaign was undertaken, and beneficiation studies were conducted on the sample using a Floatex Density Separator (FDS), a gravity device which can be operated for size classification and/or relative density separation. The objective was to produce high-quality iron ore material suitable as sinter feed. An iron concentrate with a grade around 57.0% Fe (Calcined Fe of about 63.0%) was achieved while recovering around 67.0% of the feed weight. In addition, a rejection of substantial content of Silica (>75%) and Alumina (>66%) was achieved while securing >77% iron recovery. On the other hand, sharp classification efficiency with low values of imperfection around 0.20 was obtained. Consequently, the response of the lower grade iron ore sample to FDS application, has vast potential to reject deleterious impurities as a single stage separating beneficiation equipment. Remarkably, it was demonstrated, that a great amount of goethite, abundant in lower grade iron ore fines/plant rejects, which are currently being either stockpiled and/or dumped as waste, can be treated using FDS application and potentially can add a significant value to the iron ore mining industry by recovering additional iron ore fines. Keywords: deleterious impurities, beneficiation techniques, classification, relative density separation

Sep 1, 2012

The ore studied occurred in the Three Rivers area in China and was a silver-lead-zinc complex ore containing 400.52 g/t silver, 4.77 % lead and 3.47 % zinc. Silver, lead and zinc were the major valuable elements in the ore and copper, cadmium and tin were the associated elements to be comprehensively recovered, whereas arsenic was the harmful element. The element silver occurred mainly in freibergite with small proportion in dyscrasite and other silver minerals. The carrier minerals for silver were mainly galena and oxidized lead minerals and then sphalerite, arsenopyrite and pyrite. The ore contained numerous minerals with complex mosaic texture and the lead and zinc minerals enclosed each other multiply, which made the separation of the minerals in the ore very difficult. Experimental investigation on the beneficiation of the ore indicated that with flotation separation process it was very hard to obtain single lead concentrate or single zinc concentrate that would meet the requirement of market. In the meantime, during the separation process of lead and zinc, silver tended to be dispersed, resulting in a low recovery of silver. Therefore, a rational utilization technique for the ore should be a combined process of bulk flotation to reduce arsenic? sulphating roasting of silver-lead-zinc bulk concentrate-leaching with diluted sulphuric acid to separate silver, lead and zinc. With this process quality lead concentrate containing silver and high grade zinc product and silver product could be obtained. The recovery of silver, lead and zinc in flotation was 85.10%, 84.48% and 82.48%, respectively. The total recovery of silver, lead and zinc in chemical processing was 97.07%(sum of recovery of silver ingot and lead concentrate), 99.61% and 90.93%, respectively.

Jan 1, 2014

By Venkataramana Runkana, Pradip Gautham, Beena Rai, Sreedhar Reddy

"IT enabled platforms are the key to provide an integrated view of the business activity or an enterprise as a whole. Attempts to integrate all functions in an enterprise such as mine-to-market initiatives, wherever and to whatever extent implemented, have provided significant benefits to the industry. The transformative potential of IT enabled integration platforms is illustrated in this communication from our own work in this field. TCS PREMAP (Platform for the Realization of Materials and Products) is a knowledge-driven engineering design and development platform which leverages modeling and simulation and artificial intelligence into the engineering design process. We illustrate the customization of this generic platform for the design and optimization of mineral processing plants in an integrated manner. TCS PEACOCK (Process and Equipment Analytics for Optimization and Control) has been developed to enable automation of data analytics in the operating plants. We illustrate its utility and power in improving the plant performance with the help of case studies from our work on pelletization of iron ores and optimization of flotation plants. INTRODUCTION We are living in an exciting digital era. With the advent of cloud computing and social media on the one hand and rapid advances being made in several research areas of interest to us in the minerals and metals industry such as artificial intelligence (AI) & machine learning, robotics, unmanned vehicles including drones, big data analytics, 3D printing, sensor technologies, renewable energies and internet of things (IoT), many disruptive transformations in our industry are on the horizon. Recent advances in information technology (IT) and knowledge engineering, in combination with appropriate domain expertise, that is, our enhanced understanding of the underlying science of mining and mineral processing operations and the availability of a variety of powerful modeling-simulation tools make it possible to address the challenging problems facing the mining and mineral processing industry, in an integrated manner."

Jan 1, 2018

By H. Ding

Calcium carbonate/Titanium dioxide composite, characterized by coating TiO2 on the surface of CaCO3 particles, is an important substitute for titanium dioxide. This paper studies preparation method of CaCO3/TiO2 ,composites based on mechano-chemical effects, measures its properties as a pigment, analyzes the binding form and interface reaction mechanism between CaCO3 and TiO2. Through single finely grinding of CaCO3, co-grinding of CaCO3 together with TiO2, and mecha-no-chemical effects produced in the course of grinding, CaCO3/TiO2 composites can be prepared successfully. Results indicate that grinding fineness of CaCO3, co-grinding time of CaCO3 and TiO2, the weight ratio of grinding media to mineral feeding, and the amount of TiO2 have much influence on the properties of CaCO3/TiO2 composites. CaCO3/TiO2 composites have the properties same as titanium dioxide pigment, oil adsorption and ultraviolet adsorption same as TiO2, and 90% of hiding power as that of TiO2. Wet grinding of CaCO3 causes the production of mechano-chemical effect and hydroxyl group, through which CaCO3 and TiO2 can be bonded together. Repulsion occurs between the particles of CaCO3 and the particles of TiO2, respectively, they are both in good dispersion. But attraction occurs between CaCO3 and TiO2. TiO2 particles are distributed evenly on the surface of CaCO3. Therefore, coating of TiO2 on the surface of CaCO3 particles and chemical bond between them make CaCO3/TiO2 compo-sites have pigment properties of Titanium.

Jan 1, 2014

By Olli Haavisto, Heikki Häkkänen, Tommi Kauppinen, Navid Khajehzadeh

Raman analysis is a well-established method for finding the abundant minerals in an ore sample. In this study, Raman spectroscopy is tested as a method for rapid and contactless on-line mineral analysis. Rapidness might enable on-site analysis of rock drillcore, which in turn would lead to more cost-efficient solutions in mineral exploration. This paper discusses the use of Raman analysis to identify minerals and to measure their concentration. The sample set under study consists of rock drillcore collected from Agnico-Eagle Kittilä Mine, Finland. Selected parts of the sample set are measured by Raman spectroscopy and the minerals are identified using reference spectra from a public source. Moreover, the direct measurement of concentration of different minerals with the help of Non-negative least squares (NNLS) optimisation algorithm is considered. The optimisation algorithm was constructed to form a linear combination of reference spectra which best represent the measured spectrum, or an average of measured spectra, from an ore sample. The results show that NNLS can identify abundant minerals in a given sample. Also through this method of analysis the results of a traditional point-count method can be expanded: It was observed that, due to grain size, multiple minerals consistently appear in the spectra measured over an area, which means that point-count method is not a proper way to interpret the spectra. This can be seen as a new result, as formerly the discussion has attended to other methods.

Jan 1, 2014

By J-P Franzidis, P. O. Gyebi

"Coal-water mixtures (CWM) of concentrated fine coal may be transported in pipelines but this is influenced by both CWM rheology and stability. Here, a low viscosity is required to reduce power requirements, as well as good stability for transport and storage. The objectives of this study are to investigate the importance of surface charge, solids concentration and dispersant addition on the rheology and stability of a fine Witbank coal-water mixture (<75 m). Zeta potential, rheology and stability were measured with a Malvern Zetasizer, a AR1500EA rheometer and a static rod penetration test, respectively. Sendep 30D, Sendep 30F and Norilose 8058, all supplied by Senmin International, were used as dispersants, at dosages of between 0.1 to 0.5% dry coal (w/w). Solids concentration was varied from 10 to 58% (w/w). The zeta potential was found to be positive at low pH and decreased sharply with increasing pH to a minimum of -50 mV at pH 10. The zeta potential decreased with increasing dispersant concentration for all dispersants. The lowest zeta potential of -63 mV was obtained for Norilose 8058 at a dosage of 0.3%. CWM rheology was Newtonian at lower solids concentrations but became non-Newtonian at solids concentrations over 40% (w/w), with an initial yield stress and pseudo plastic behavior. The yield stress decreased sharply with increasing dispersant concentration for all dispersants. The lowest yield stress was obtained for Norilose 8058. The addition of dispersants resulted in significant improvements in stability. A penetration ratio of over 70% was obtained for Norilose 8058 after 10 days. In summary, the addition of dispersants resulted in a decrease in the zeta potential which increased the electrostatic repulsive forces between particles, thus improving both CWM rheology and static stability.INTRODUCTION Coal Water Mixtures South Africa’s energy economy depends heavily on coal. It accounts for about 70% of primary energy consumption, 93% of electricity generation and 30% of liquid petroleum fuels (Eberhard, 2011). The transportation of coal to export markets and power generation stations is a problem in the South African coal industry due to ageing and inefficient rail infrastructure. This problem is intensified by the long distance of coal haulage, delays in the time required to load and unload wagons, and environmental challenges related to air pollution and water contamination. Fine coal may be transported more efficiently and economically in a pipeline as a highly concentrated coal water mixture (CWM). Typically a fine coal CWM will contain 60-75% coal, 25-40% water and nearly 1% of dispersing additives (Atesok et al., 2005; Dincer et al., 2003). However, the transport of CWMs in pipelines is strongly influenced by both CWM rheology and stability. Here, a low viscosity is required to reduce power requirements, as well as good stability for transport and storage. These quantities are affected by the coal composition/mineralogy, solids concentration, particle size and size distribution, particle shape, inter-particle forces and dispersant type and dosage (Laskowski, 2001)."

Jan 1, 2018

By K. Gonçalves

One of Vale?s sponsored research project is aimed at the implementation of a practical scale-up procedure for flotation. In this context, detailed flotation kinetics characterization is of critical importance. This work presents the results of a campaign aimed at characterizing flotation kinetic parameters with respect to particle composition. MLA analysis was carried out for 40 narrow-sized iron ore particles with known flotation time from a controlled flotation kinetic test. The iron ore sample studied (59% hematite and 41% quartz) comes from a mine in the southeast of Brazil and the type of reagents applied are the same as used in the plant. For the reagent conditions tested, the overall rougher concentrate (sink) yielded 79.1%, pure quartz and hematite recoveries to the froth were 56.0% and 4.8%, respectively. The results from the kinetic tests show that the flotation rate of the particles doesn?t vary much (~0.03s-1) with composition and that the fraction of floatable particles in each grade controls the separation action. The results show that the rate of flotation is controlled by transport and that the selectivity is controlled by the fraction of floatable particle of each phase.

Sep 1, 2012

By Caibin Wu, Ali Lei, Ningning Liao, Jingsheng Ye

"The particle size distribution characteristics of ground product can influence the quality of the classification overflow and the next beneficiation indexes in an ore concentrator. Usually, the size distribution of ground product is considered to be determined by that of new ball mill feed. However, based on large amounts of data from industrial grinding circuit surveys, this paper has clearly shown that the size distribution of ground product should be determined by the size characteristics from classification underflow unless the circulating load was small, because the new feed is an important component and occupy a dominant position of mixed ore from belt feed and classification underflow. On the other hand, the correlation coefficient of the size distribution between ground product and classification underflow can be more than 0.99 when the relevance principle and its method are used. Meanwhile, their P80 value also keeps a synchronous correlation. The greater the capacity of classification underflow is, the higher the correlation of size distribution between the ground product and the mixed feed is. Furthermore, the correlation coefficient of the size distribution between ground product and classification overflow which is from primary or secondary can be 0.96. It is another discovery that the correlation coefficient is related to the type of classifier. The coefficient of size distribution of overflow and underflow from hydrocyclone is superior to that of spiral classifier, which can explain the reason why the hydrocyclone is widely used to replace the spiral classifier in concentrator.INTRODUCTION It is well knows that ball mill circuits closed with cyclones or spiral classifier such as a primary grinding circuit, a secondary grinding circuit and SAB mill have become an industry standard. Which grinding process employed will be determined by the P80 value of ground products. When the primary closed circuit ball mill or SAB that it is different throughout between the two processes was employed, a grinding fineness with -200mesh under 68% will be available. However, the secondary grinding circuit with the fineness of -200mesh above 80% can be conducted. Of course, the grinding fineness is determined by the grain size characteristics of the mineral."

Jan 1, 2018

By K. Price, G. Wang, L. R. Moore, Y. R. Xiong, J. Gu

"Sand is a naturally occurring granular material that is a result of the physical or chemical breakdown of rocks. Raw/natural sand contains various minerals, and it is this combination of minerals that brings the value to the construction aggregate industry. However, it is the quartz component of sand that is valued in its application as industrial silica in glass, high purity quartz, foundry sand, and oil and gas fracturing. Depending on the industry, the grade requirements can be the concentration of SiO2, particle size or shape, as well as contaminants such as the heavy refractory minerals, clays, fines, and alkali metals. With the ever declining mineral feed grade, processors continue to face challenges making the industry specific concentrate grade. As such, it becomes more important to tailor make the processing reagents to fit the mineral, processing conditions, and desired quality specification. This paper focuses on the application of novel collectors towards the beneficiation of sand for each of the major industrial silica applications. INTRODUCTIONQuartz is a mineral composed of a framework of silicon and oxygen atoms. It is the second most abundant mineral in the Earth’s continental crust. There are many species of quartz, which are defined by the particle size, shape, and color. Silica sand is one of those species, which is the byproduct of the physical or chemical breakdown of quartz containing rocks or crystals. Geologist define silica sand as a silica mineral with a particle size between 0.05 and 2 mm in diameter (Zdunczyk, 2001). Silica sand has significant value to society in recreation (beach sand and toy boxes), construction aggregate (concretes and asphalt), industry (iron & steel casting, fracturing proppants, and glass), as well as specialty products such as semiconductors or silicon wafers used in electronics.The aggregate business is the dominant consumer of silica sand products. Conversely, glass making, foundries (casting material), abrasives, and fracturing proppants are the dominant applications for industrial silica sand. Not much beneficiation is required for sand products going into the construction industry, other than sizing and scrubbing to remove clay. However, the industrial silica sand applications are dependent on particle size, shape, and degree of contaminants, which sets the market value (table 1). Therefore, as the more specialty products are produced, more sophisticated techniques and chemistry need to be applied to ensure the appropriate quality is met."

Jan 1, 2018

By S. Q. Zhu

A newly developed coal flotation collector ZFC and its flotation characteristics for five different coals were introduced in this paper. ZFC is an emulsion composed of 27% diesel oil, 70% water and 3% surfactants. The main surfactant is synthesized with oil which is environmental favorable and reproducible. Compared flotation experiments show that, at the same dosage, ZFC give 2%~5% recovery promotion than typical collector with only a slightly ash content increment, but saving 70% diesel oil. Zeta-potential and Wetting heat measurement indicate that the surfactant helps the interactions between oil and coal particles, the industrial application tests in several coal preparation plants demonstrate that ZFC is suitable both in technical and economical aspects.

Jan 1, 2014