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By A. M. Raichur, S. P. Vijayalakshmi

Fine coal dewatering is a major problem in the coal industry because the fines hold significant amounts of water and account for two-thirds of the product surface moisture. Present methods include flocculation using polymeric flocculants followed by filtration. But the kinetics of filtration are not favorable with such flocculants. In this study, a novel method involving flocculation with microorganisms for improving the settling rates and dewatering kinetics has been investigated. Two Gram-positive microorganisms, Mycobacterium phlei and Bacillus subtilis were used as bioflocculants. The effect of time, pH and ionic strength of the electrolyte used on adhesion and flocculation were studied. Adhesion tests showed that maximum adsorption occurred in 20 minutes in the pH range of 2-7 and the total amount of bacteria adsorbed was almost the same with both the flocculants. Nearly 98% of the coal flocculated with both the microorganisms in about 5 minutes. The filtration rate of fine coal almost doubled with addition of bacteria and electrolyte and maximum filtration occurred near the point-of-zero-charge of the bacteria.

Jan 1, 2003

By I. I. Beloglazov, G. A. Iusupov, A. Ju. Feoktistov

"The aim of this paper is to study the numerical modeling of the crushing process in a jaw crusher with complex motion jaws using Discrete Element Method (DEM). The main goals are to ensure the conformity of numerical simulation results to the experimental data, optimize the operating modes and the crusher design and develop automated verification and calibration methodology. It is offered to use automated selection of mathematical model parameters using large- or laboratory-scale experiments instead of deriving parameters from conventional intensive material tests (e.g. drop-weight test). Experimental data were obtained from a large-scale crusher designed and manufactured by the company “Mekhanobr-Tekhnika”. Both jaws have their drive shafts located asymmetrically; one jaw is driven in the upper part, the second at the base. The crushing process involves fragmentation of single smoothed rectangular granite particles of the same weight. During the experiment, the required parameters such as particle size distribution were obtained for further computer simulations. Based on the obtained experimental data, the Rocky DEM model was built. Simulation breakage parameters were calibrated using automated parameter selection methodology based on multiple set of parameter-controlled simulations. A good correlation of the experimental data and numerical simulation data was obtained. The methodology in combination with well-known capabilities of simulation modeling will help reduce the research time in the development of new mineral processing equipment.INTRODUCTION Preparation of rock mass for enrichment includes the power-consuming processes of crushing and grinding. Initial rock mass crushing is performed by means of drilling and blasting operations. To reduce the average size of a rock piece, primary crushers, mostly jaw crushers, are further applied. The advantages of the jaw crusher are simple design, easy maintenance and repair. One of the drawbacks is large oscillating masses and, thus, high power consumption during operation (55 - 200 kW). Jaw crushing simulation will help optimize the crushing process and improve further rock transportation and processing performance."

Jan 1, 2018

Three high-grade limestone ores (CaO content over than 53 %) with different geological origin have been characterized for the synthesis of aragonite precipitated calcium carbonate. Limestone ores examined in this study showed different crystal particle size that cause difference in disintegration degree and surface area of the synthesized slaked limes. The limestone ore with smaller crystal particle size showed higher disintegration degree and also yielded slaked lime with smaller surface area, which is good for the synthesis of aragonite precipitated calcium carbonate. The synthesis of aragonite PCC using the limestone with a small crystal particle size was yielded needle-shaped aragonite with the aspect ratio of about 14. Keywords: limestone, lime, slaked lime, precipitated calcium carbonate, aragonite, accelerated carbonation

Sep 1, 2012

By R. Venugopal

The paper reviews the development of Mineral Engineering education and training programmes in India. It highlights the major academic programmes and describes the evolution of the curriculum and design of courses in response to the changing requirements of India?s mineral and coal industries. An outline of the efforts needed to sustain and further improve the existing programmes is also provided. Keywords: manpower, mineral engineering

Sep 1, 2012

By Shailin Lalloo, Allan B. Nesbitt

A fluidised bed was exposed to high gravities by placing it in a centrifuge. The bed expansions were measured and compared with the bed expansions predicted by the Richardson-Zaki model (1954). The Richardson-Zaki model was found to predict effectively the fluidisation behaviour of defined particles in this increased gravity environment.

Jan 1, 2003

By Robert Peretti, Antonio Zucca, Andrea Manni, Silvia Serranti, Paolo Massacci, Marcello Ghiani

"This research study aims to identify the best way of processing colemanite concentrates, which is sometimes characterised by a high content of As sulphides, finely disseminated in the matrix of the boron mineral.Scanning Electron Microscopy analyses have been carried out to identify all the mineralogical constituents and to evaluate their distribution, frequency and mutual relationships.Colemanite concentrates are mainly used by chemical plants producing boric acid and gypsum. A high As content is unacceptable for further use of tailings coming from the leaching process and is very dangerous if the tailings are released into the environment.Grinding tests were conducted under dry and wet conditions in order to assess how As sulphide minerals are released from colemanite minerals.Some of the difficulties involved in obtaining selective liberation of As sulphides from colemanite minerals were overcome, although a certain decrease in As grade in the higher size classes was registered.All comminution products have been analysed by SEM, monitoring the degree of liberation of the mineralogical constituents.Flotation tests have been carried out, following different comminution flow sheets and adopting different modulating conditions in order to evaluate the influence of the following parameters:- collector concentration versus contaminants concentration (As minerals) in the froths;- kind and quantity of the frothing agent to maximise mineral recovery in the froths;- kind and quantity of the modulating agents to maximise the selectivity of the process;- conditioning modalities in order to obtain a suitable dispersion of fines and avoid segregation of Asbearing particles together with colemanite ones;- solid/liquid ratio of the pulp to minimise the water flow into the plant.Information obtained from SEM analysis has been adopted to evaluate segregation phenomena in pulp and in flotation products."

Jan 1, 2003

By A. V. Kanarskay?

The research is aimed at involving in the processing of poor platinummetal natural and technogenic raw materials. The purpose of the research is the creation of a multifactorial complex of innovations in the system of ore preparation and separation cycles, which ensure a high efficiency of flotation enrichment of hard-to-treat raw materials. In the usual practice of enrichment, minerals of the platinum group (PGM) of less than 10 microns in size are the source of inevitable process losses. For poor raw materials, it is precisely thin PGMs that are characteristic, their proportion sometimes being almost 100%, and their opening leads to the formation of a large amount of slime, which adversely affects the efficiency of flotation. To reduce the yield of slimes and increase the selectivity degree of the opening of the PGM in the ore preparation cycle, a dry grinding scheme and pneumoclassification of the milling material has been developed to obtain fractions of different fineness, density and morphology of the particles. From 2 to 5-fold reduction in the yield of slurries for various ores has been achieved. The separation cycle successfully tested are: flotation of fractions in separate cycles with a differentiated choice of the reagent regime; preliminary selective flocculation of slime fraction material; use of a new generation of bioreagents for flocculation and flotation. A new approach to subsoil research is protected by a patent. The dependence of the efficiency of biocollectors on the composition of biomineral extract from the processed raw materials, which forms the basis of new reagents, is established. The possibility of obtaining the degree of extraction of PGM, native gold and sulphides from finely ground pre-fractionated poor ores with the use of biocollectors of at least 85% is proved. With conventional reagents, the extraction of PGM is 12-23% lower, with the use of traditional ore-preparation apparatuses, the PGM recovery rate was halved. Methods for the long-term storage and preparation in industrial conditions of biocollector reagents that do not require the purification of waste waters from them have been developed. The developed multifactorial system of intensification of flotation enrichment can be introduced to recovery PGM from tailings of enrichment of titanomagnetite, chromite and copper-nickel ores.

Jan 1, 2018

By V. V. Trusova, Shiyrav Gandandorzh, K. V. Fedotov, V. A. Domracheva

"In Russia, 1.1 million tons of mercury-containing waste are stored. The amount of mercury in soils and heaps of industrial enterprises is estimated at 3000 tons; in dumps, concentration tailings, sludge dumps of the gold mining industry up to 6000 tons have been accumulated. Mining is one of the main sources of mercury emissions in the natural environment that poses a real threat to the natural environment. At present, the process of amalgamation is prohibited and not applied in gold extraction. The application of amalgam technology in gold mining led to the accumulation of highly toxic products in the form of gold-bearing amalgam and metallic mercury, with a mercury content of dozens and even hundreds of times greater than the maximum permissible concentration for soil (1). Therefore, mercury-containing tailings constitute an ecological hazard to the environment. According to published data, at waste storage sites of industrial enterprises, up to 50 tons of mercury enter soil annually, and up to 3.5 tons pollute the air. At the same time, mercury-containing waste due to the reduction of the country's mineral resources is an additional source of mercury. Therefore, it is necessary to recycle mercury-containing waste. INTRODUCTION Paperobjective: demercurization of technogenic raw materials (amalgamation tails, discharge outlets of tailing dumps) to be recycled. Under natural conditions, the mercury usually migrates in the form of three most common compounds: elementary mercury (Hg); mercuric mercury ion (Hg+2); methylmercuryion (Hg (CH3) +. Chemical compounds Hg (II) are found in natural conditions much more often than Hg (I).The authors propose to conduct demercurization of technogenic raw materials (mercurial tailings) in two stages. At the first stage, the mercury in the form of small balls, the finest particles (drip mercury) can be extracted by applying the gravitational method. We propose a method for centrifugal processing of crushed waste in the apparatus of Itomak company, Novosibirsk, as the basis of the technological process for mercury recycling. The extraction of metallic mercury out of mercury-containing waste into commercial products, according to the technological characteristics of the Itomak apparatus, reaches 86.0% (2, 3). At the second stage, the extraction of mercury out of technogenic raw materials is performed applying a sorption method and using carbon sorbents based on fossil coals. Hard coal of the Kuznetsk Basin has been already used for industrial production of active carbons (carbon sorbents) of the KAD-iodine type, which is one of the prerequisites that determine the choice to use it for the aims of this study."

Jan 1, 2018

By Mohammad Noaparast, Hamed Haghi

"In this research work, it was attempted to reduce the iron contents (Fe2O3) in relatively low grade silica sample which was obtained from Shenin silica mine, using magnetic separation. The prepared sample contained 93.75%SiO2, 0.44%Fe2O3, 2.78%Al2O3, and 0.08%TiO2 and the Fe2O3 had to be reduced to less than 0.08%. Mineralogical studies and XRD analysis indicated the presence of Hematite, Pyrite, and Goethite as the major iron impurity phases. Mineralogical studies of polished and thin sections demonstrated that the degree of freedom of silica is more than 80% in -300+212 ?m size fraction. After primary stages including crushing, milling, scrubbing and de-sliming, various methods such as low intensity magnetic separation (LIMS), high gradient magnetic separation (WHGMS) and dry high intensity magnetic separation (DHIMS) were applied to find out that which process would be appropriate for the elimination of iron impurities from this sample. Different experiments were carried out on the product of wet rod mill and scrubber. However the magnetic field intensity of WHGMS was increased down to 2Tesla, and there was not any acceptable result in reduction of Fe2O3 content lower than 0.08%. Thereafter the product of wet rod mill and scrubber were dried and reported to DHIMS. In these experiments, maximum magnetic field intensity was 1.4Tesla. In this case very significant results were achieved, and Fe2O3 content of final product were reduced to less than 0.05% which meets glass manufacturing standards."

Jan 1, 2014

By Mohsen Hashemzadehfini

Nowadays heap leaching has become established as a mineral processing technology for treatment of some low grade minerals such as copper, gold, and zinc, etc. Heap height, particle size, leach reagent consumption, and metal recovery are four important metallurgical parameters in a hydrometallurgical process like heap leaching. This paper investigated the effects of heap height and particle size on copper recovery as well as acid consumption. Three heap heights of 2, 4 and 6 meters and two particle size fractions of less than 25.4 mm and 50.8 mm were selected as variables in the experiments. The research results showed the inverse relation between heap height and copper recovery as well as acid consumption. Under given conditions, the copper recoveries of minus 25.4 mm ore are 78.63%, 66.27% and 52.88% higher than that of minus 50.8 mm samples for the heap heights of 2, 4, and 6 m, respectively. Both copper recovery and acid consumption increase with decreasing particle size. Keywords: heap leaching, heap height, particle size, acid consumption

Sep 1, 2012

By G. X. Du

Reaction kinetics of serpentine and hydrochloric acid is theoretical basis for optimizing reaction process conditions of serpentine and hydrochloric acid. Kinetics of serpentine and hydrochloric acid was studied in this paper. The results indicated that apparent reaction order to hydrochloric acid was two and reaction kinetic equation could be expressed as: 2HClHCl,ddtckct-=·. The diffusion rates of hydrogen ions in liquid film on surface of serpentine particle and in amorphous silica layer generated in the reaction and chemical reaction velocity during the reaction had important effects on to-tal reaction velocity. And chemical reaction velocity had the most significant influence. The relation of conversion rate of magnesia xMgO with reaction time could be expressed as: 1(1)xkt--=·.

Jan 1, 2014

By Kwan Ho Kim

In this study, free fall tests are conducted with the objective of understanding the breakage properties of waste concrete for the guide of the direction of the better comminution process. Waste concrete of 75mm×53mm is tested at various drop heights with or without heat pretreatment. Test results indicate that a block of waste concrete does not break by free fall, but eventually breaks by repeated free falls. The number of free falls required for complete separation of large aggregates from the cement mortar considerably reduced when the samples were heated at 400?. Therefore, a great energy saving can be obtained when heating the waste concrete prior to crushing. The energy saving was found to be dependent on the height of free fall but in all cases, was still large enough to offset the additional energy required for heating. Also, it was found that the heat pre-treatment gives an additional advantage in that it produced cleaner recycled aggregates. This may result from easier detachment of cement mortar from the aggregates due to weakening of bonding forces by heating. By analyzing the size distribution of the crushed product, a free-fall breakage model is developed using the particle breakage ratio and the breakage pattern. The developed model can be used to predict and to analyze waste concrete processing circuit.

Jan 1, 2014

By Y. B. Zhang

China is rich in iron ore resources, but most of these ores are low-grade, polymetallic and refrac-tory ones. Furthermore, with the rapid development of chinese iron & steel industry, the comprehen-sive recovery of these ores is becoming more and more important. The tin, zinc-containing complex iron ores are typical polymetallic and intractable ones, and great reserves of them are found in China. At present, they have not been efficiently utilized. In this paper, based on the investigation of basic physicochemical properties of the tin, zinc-bearing iron concentrates, taken from a mineral processing plant, the mineralogy reason that these concentrates are so intractable and refractory is found out, using advanced microscopic testing methods, such as optical microscope (OM), Scanning Electronic Microscope (SEM), X-ray diffrac-tion (XRD), etc. It is found that the symbiotic relationship of iron, tin and zinc metallic minerals are very complicated, and magnetite in the concentrate is closely symbiotic or enwrapped by fine cassi-terite and sphalerite. So it is difficult to separate tin and zinc completely from the iron concentrates by simple regrinding and physical separation method. This investigation provides theoretical guid-ance for developing new approaches for utilizing these concentrates.

Jan 1, 2014

By Zhu Yangge, Zheng Guibing, Hu Xiaoxing

"Because of the similar crystal structure and surface properties, it is very difficult to realize the efficient separation of magnesite and dolomite by flotation, which is the main reason restricting the utilization of magnesite resources with dolomite symbiotic. To deal with a magnesite resources with high content of calcium impurity in northwest China, a novel decalcification technology by combining flotation with leaching is proposed in this paper. In flotation process, a novel flotation collector with good efficiency and low temperature resistance was developed, and the depression effect of sodium hexametaphosphate was investigated. In leaching process, the leaching rate difference of calcium and magnesium was observed. By industrial test, from the magnesite ore with MgO content of 43.96%,the grade and recovery of obtained concentrate ( calculated by MgO) are 47.28% and 67.68% respectively, at the same time, CaO content decreases from 3.91% to 0.30%, which means that more than 95% of CaO impurity is removed.INTRODUCTIONMagnesite is one of the main raw materials for the production of refractory materials, and it is widely used in metallurgy, chemicals, ceramic, construction and other industries. China is the most important supplier of highquality magnesite resources, accounting for about 60-70% of the world's identified supply of magnesite products is provide by China (Jewell, 2014). In recent years, high-quality magnesite ores can be directly used are going to run out in China, and the utilization of magnesite resources with high impurity content have drawn more attention.The main purpose of purification for magnesite is to remove SiO2 and CaO impurities which affects the strength of the refractory material. Flotation is the commonly used method to remove impurities in magnesite ore. Reverse flotation with cationic collector is usually adopted to remove silicon containing impurities, and a great deal of literature has been reported (Santana A. N. and Peres A. E. C., 2001; Wang and Sun, 2008; Zhu et al, 2014; Wu et al, 2015; Ivan B. et al, 2017). But when the major gangue component is dolomite, it is very difficult to realize the efficient separation due to the similar crystal structure and surface properties between magnesite and dolomite. To solve this problem, researches have studied the surface properties of magnesite and dolomite, such as wettability, electrical property, solubility and solution chemistry (Nermin and Nurgul, 2006; Nermin 2006; Ozbek and Abali, 1999; Lacin et al, 2005; Bayrak et al, 2006; Bakan et al, 2006; Chen G. and Tao D., 2004), but the commonly studied direct flotation using oleic acid as collector is still hard to receive an ideal effect."

Jan 1, 2018

By Y. M. Zhu, G. C. Gong

"The influences of citric acid (CA) on the flotation behavior of cassiterite using styrene phosphonic acid (SPA) as the collector were studied via single mineral flotation tests, contact angle measurements, zeta potential determinations and solution chemistry calculations in this paper. The results of single mineral flotation tests revealed under the conditions that pH=4 and the dosage of SPA 100 mg/L, the recovery of cassiterite reached 76.78%. The addition of 20 mg/L AC decreased the recovery by 12.42% at pH=4. Contact angle measurements demonstrated the adsorption of CA prior to SPA made the cassiterite more hydrophilic. The results of zeta potential determinations and solution chemistry calculations indicated the chemisorption of C6H7O7- and C6H6O72- filled parts of the Sn site on cassiterite surface and prevented the SPA from getting adsorbed. The hydrophilic effect of AC was stronger than the hydrophobic effect of SPA and the flotation of cassiterite was crippled. INTRODUCTION Tin is an important metal which is widely used in medical instruments, marine engineering materials, electronic and electrical devices, welding, weapon manufacturing and organotin compounds industries (Angadi et al., 2015). Cassiterite is the only mineral from which the tin can be extracted, thus it is of great importance to efficiently exploit the cassiterite mineral. Flotation is an indispensable method for the recovery of cassiterite (Li et al., 2015). However, cassiterite is usually in association with many other gangue minerals which are of similar floatability, such as quartz, calcite, fluorite, iron oxide, wolframite, scheelite and tourmaline (Sreevinas, 1997). So some modifiers are necessary in the cassiterite flotation process. The amounts of the modifiers used in the flotation must be judicious and the overmuch modifiers may cripple the recovery of cassiterite (Parsonage et al., 1987). Nevertheless, the research about the effects of the modifiers on the flotation behavior of cassiterite has been rarely reported. In this paper, the influences of citric acid (CA) on the flotation of cassiterite using styrene phosphonic acid (SPA) as the collector were investigated by flotation tests, contact angle measurements, zeta potential determinations and solution chemistry calculations."

Jan 1, 2018

By Agnieszka Surowiak, Tomasz Niedoba

The paper presents a way of determining relations between ash content in coal, particle size and particle density by means of regression, multidimensional Morgenstern distribution functions and kernel approximation. The three-dimensional random vector (D, ?, ?), where D is a random variable describing particle size, ? - random variable describing particle density and ? - random variable describing ash content, where function ?=?(d, ?) is obtained by means of regressive function. The multidimensional Morgenstern distribution functions and kernel estimators with the use of Gauss function were applied to approximate the functions f(d, ?, ?) and f1(d, ?). This approach is a new way of multidimensional description of grained materials such as coal and it also allows to evaluate material features more properly than the classical statistical approach. The results were verified statistically.

Jan 1, 2014

By Xing Yang, Zhen Peng, Guangwen Zhang, Haifeng Wang, Yaqun He

"Triboelectric separation of ilmenite ore based on the tribocharge differences between ilmenite and gangue minerals was conducted in this study. Triboelectric characteristics of ilmenite and its associated minerals were studied using polyvinyl chloride (PVC), pentatricopeptide repeats (PPR), copper, polymethyl methacrylate (PMMA), stainless steel (SS), teflon and quartz glass (QG) tribochargers in lab triboelectric unit. Results demonstrated that the ilmenite particles tribocharged positively while gangue minerals tribocharged negatively using PVC as tribocharger. The particle size also has a significant effect on tribocharge, and the -0.125+0.074 mm is the optimal size fraction of triboelectric separation. Charge-mass ratios of minerals increase with the increases of tribocharging length, but the increasing rate gradually reduce. At 1.5 m tribocharging length, charge-mass ratios of ilmenite, quartz, feldspar and mica are up to 6.07 nC/g, -6.05 nC/g, -4.30 nC/g and -4.56 nC/g, respectively. Based on the triboelectric characteristics of each mineral, triboelectric separation of ilmenite was conducted, and the grade of ilmenite ore increased from 15.47% to 28.40%. INTRODUCTION As a transition metal titanium plays an irreplaceable role in medical, aerospace and materials due to its light weight, high strength and corrosion resistance. Pure titanium dioxide is an excellent white pigment and is widely applied in industries of paint and textile. Ilmenite is the main raw material for titanium industry. For the beneficiation of ilmenite, series methods have been proposed, such as the application of dry magnetic and wet gravity separations to separate the ilmenite from the zircon and rutile. Electrostatic separation is extensively used in the beneficiation of heavy mineral sands for the recovery of rutile, zircon and ilmenite while flotation is used to separate fine ilmenite (Mehdilo et al., 2014; Fan et al., 2014). Compared with flotation and gravity separation, electrostatic separation does not consume water, and native properties of materials will not be changed and energy consumption will be reduced (Wang et al., 2014). Thus, the wide application of electrostatic separation and other dry separation methods is a trend in separation and purification industry, especially in water-scarce areas."

Jan 1, 2018

By B. Z. Wu

The ore dressing of tin-polymetallic lean ores is a difficult problem and the research emphasis in domestic nonferrous metals mining field. Through research and tackle key problem,and in order to supply reference in dealing with the same types ores, this paper expatiates the exploiture and appli-cation of six item new technology and technics in ore dressing of tin-polymetallic lean ores. It include the technics of multi-step compounding disposing tailings, grinding step by step, grinding and processing circularly technology, high thickness without circle flotation technology, dispersedly flotation tin step by step technology, exceed fine lean plumbum stibium zinc flocculation flotation technology, the synthetically recovery of waste water after ore dressing technology.

Jan 1, 2014

By D. Pienaar, B. McFadzean, T. Jordaan

"Dithiophosphate (DTP) collectors have the lowest affinity for sulfide mineral surfaces compared to other common sulfide mineral collectors, such as xanthates and dithiocarbamates. In some cases it has been found that DTP does not adsorb onto the mineral surface at all and yet increases in recoveries and grades are noticed with the addition of DTP. Many studies have investigated the interactive effects of collector mixtures. However, there have been relatively few studies on the interactive effects between frother molecules and collectors. This study investigates the interactions between different types of frothers and sodium diethyl dithiophosphate.The study found that there were large increases in pyrite and galena microflotation recoveries at both pH4 and pH9 when DTP was mixed with small amounts of frother at a constant bubble size, showing that these increases were neither mineral-specific nor pH-specific. The same effect was not present when xanthate was used as a collector. The increases in recovery when using the DTP-frother mixture were similar irrespective of the type of alcohol or polypropylene glycol frother that was used. In an attempt to distinguish the mechanism of enhanced flotation recovery, various supplementary experiments were performed. It was found through adsorption experiments that no DTP was adsorbing on to the mineral surface. Therefore, interactions at the air-water interface were performed. Surface tension and critical coalescence concentration tests showed that, while DTP is a weak surfactant at the air-water interface, it does not have a synergistic effect in the presence of frother. DTP-frother mixtures do, however, show interactions in the froth phase, indicating an interaction in the thin films. It is proposed that there is a DTP-frother interaction on the bubble surface that enhances the rate of film thinning at the 3-phase bubble-particle contact."

Jan 1, 2018

By T. Onnela

Metso Mining and Construction Technology is one of the world leading suppliers of equipment and knowhow for aggregate and mining industry. The processing capacity, ease of use, and reliability are featuring Metso?s state-of-the-art cone crushers. Crushing is a complicated process affected by numerous parameters. The optimized crusher kinematics is one of the key factors for high performance. To fine tune the crusher kinematics and crushing chambers one needs to know how different parameters affect. The main cone crusher parameters are head angle and diameter, gyration point, shaft speed, eccentricity, stroke length, and inclination and design of crushing cavity. Selecting the correct combination of these parameters is a multi task optimization challenge. In practical life there are more factors to achieve satisfactory performance, like crushing chamber wear and profile management keeping the performance constant over the whole wear life, control of crusher frame loads, ability to handle disturbances in feed material etc. The extensive research work has lead to a solution that enables the highest possible material density in the crushing chamber. This design provides maximum reduction of processed material and thus increased share of 0/10 mm product. High density in the cavity offers further benefits, such as high throughput capacity, less material contact with wear parts and even load on crusher frame and bearings. The challenge that an equipment supplier involved with high density crushing is how to design a robust cone crusher, which is able to cope with the high crushing forces due to high resistance from the crushed material against the gyration movement. Metso has launched a new series of cone crushers HP3, HP4 and HP5 that are all able to work in high density crushing applications The test results and evidence from over 300 installations clearly prove the effectiveness and importance of high density crushing. Keywords: cone crusher, crushing chamber, crusher kinematics

Sep 1, 2012