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By Willis Forsling, Prabhakar Swarna, Hanumantha Rao Kota

"The solubility of wollastonite and its Hallimond flotation behavior as a function of dodecylamine concentration and pH are examined. The flotation response is characterized by adsorption and surface energy in the presence of amine. The methods of UV-Visible and FT-IR spectroscopy for adsorption and sessile-drop contact angle for surface energy estimation are employed.The results of wollastonite dissolution clearly showed its non uniform dissolution. The surfaces are depleted with calcium ions and became rich in silicon within 10 min of flotation time. Maximum flotation of wollastonite corresponds to a half monolayer coverage of amine, which is substantiated by the surface energy parameters as shown in figure 1."

Jan 1, 2003

By Kazutoshi Haga, Atsushi Shibayama, Altansukh Batnasan

The objectives of this study were to propose a viable alternative method for recovery of precious metals such as gold (Au), silver (Ag) and palladium (Pd) from waste printed circuit boards (WPCBs) and to regenerate the spent lixiviant solution for reuse. The proposed method generally consists of several steps as follows: 1). iodine-iodide leaching for metals extraction; 2). separation and recovery of precious metals and metal impurities from a pregnant leach solution; 3). regeneration of the spent iodine-iodide solution/lixiviant. In this method, more than 99% of Au leaching was achieved in the iodine-iodide solution from the solid residue of WPCBs that was obtained via sequential processes including incineration at 800 ?C and high pressure oxidative leaching with a diluted sulfuric acid at 120 ?C, while the leaching of Ag and Pd was less than 1%, respectively. Besides Ca, Cu, Ni, Co and Zn as main metal impurities, leaching efficiency of other metals did not exceed 1%. The precious metals and base metals as metal impurities present in the pregnant leach solution were separated and recovered by precipitation using L-AA and NaOH solutions. About 99.8% Au, 81.7% Ag and 72.8% Pd were recovered from the pregnant solution at pH of 2 with the addition of 0.1 M L-AA as precipitating agent. The remained small amounts of precious metals and metal impurities were precipitated at pH 13 using 1 M NaOH. The spent lixiviant after sequential precipitation was regenerated in the presence of hydrogen peroxide, hydrochloric acid and potassium iodide. It was revealed that over 90% of gold could be extracted from the residue of WPCBs with the regenerated lixiviant solution.

Jan 1, 2018

By Yagmur Sirinyurt, Ayhan Ali Sirkeci, Gülay Bulut, Mustafa Özer, Tuncer Acar

"The basic requirement of glass industry for the silica sand is at least 99% SiO2 content. On the other hand, coloring impurities such as Fe and Ti, must be removed. Flotation is the most widely used method for the purification of silica sands from impurities. In this study experimental studies were carried out to reduce Fe content of Mersin (Turkey) district silica sands by flotation. Silica sand sample with a d80 particle size of 1.85 mm was reduced below 0.5 mm in size. Then the size fraction -0.5 +0.106 mm was subjected to flotation tests. In flotation tests, sulfonate-type R801-R825, fatty acid based DER NA 7 (Produced by a Turkish company) and HA110-HA150 a blend of various chemicals produced by Mersin Cam-Is Mining Company (producer of glass raw materials) were used as collectors. Flotation tests showed that sulfonate type R801-R825 collectors provided much better results in acidic medium (pH: 3). The optimum pH value for DER NA, HA150 and HA110 collectors was found to be 7. It was observed that the addition of collector at once caused an increase in the amount of floated product that resulted in a loss of silica to the tailings. In the case of multistage addition of the collector much better selectivity was achieved. As a result of flotation tests conducted under best conditions, a concentrate assaying 0.046% Fe was obtained with a weight percentage of 93.4 when DER NA 7 was used as a collector. In the case of R801-R825 a concentrate was produced with 0.058% Fe content with a yield of 98.4%. On the use of HA150-HA110 the concentrate was produced with 96% weight recovery and 0.052% Fe content."

Jan 1, 2014

By P. V. Malyarov

"This paper examines the grinding and wear processes in drum mills. A summary of the industry’s long-term experience with the proposed linings is presented. A method is proposed for assessing the efficiency of the grinding energy distribution between the successive stages. A case study is presented of grinding energy redistribution at Talnakh Concentrator by replacing spiral classifiers with a drum-type hydraulic screen. The problems of the kinetics of grinding processes in ball mills and semi-autogenous (SAG) mills are examined. It is demonstrated that in ball mills the feed particles are disintegrated by triaxial compression in the mill zones where discrete slippage of the charge occurs at major force interactions between the layers. Mechanism underlying increases in the specific energy consumption in grinding circuits based on SAG mills is shown.The problem of improving the throughput and reducing the specific energy consumption in mineral feed grinding is highly relevant because of the significant energy intensity. Up to 80% of the consumed energy is used to disintegrate ore fed into the drum mill. At all development stages of the drum mill grinding theory, the researchers have paid a great deal of attention to studying the patterns of the charge motion and the kinetics of the feed particles disintegration processes. In [1], it was shown that, due to the slippage between the charge layers being lifted, drum mills at concentrator plants operate in a mixed cascade and waterfall mode. A feature of the mixed mode is the toe zone, where the charge contacts the lining and the transition to a circular path takes place. Studies of the charge motion in the toe zone made it possible to develop a method for designing cross-sectional profiles of lining plates [2] for ball mill drums. The method is based on the principle of interaction between the balls and the lining, where the non-working rear surfaces follow the relative motion path of the balls before impacting the lining, while the working surfaces are orthogonal to the rear ones. Lining with the proposed profile provides contact with the charge and slippage-free transition to a circular path. This ensures an longer service life of the lining, a reduction in specific energy consumption, and an increase in the mill’s feed rate. The proposed method is applicable when designing lining plates of various materials. Steel liners with the proposed profile have been successfully operated [3] for more than 40 years at a number of projects in the industry."

Jan 1, 2018

By Xingshi Yang, Ghislain Bournival, Seher Ata

"Particle-laden interfaces are a fundamental research topic in froth flotation since the process involves particle-coated bubbles in both the pulp and the froth phase. In most experimental studies the characteristics of the particle layer in multi-bubble systems are poorly defined. An experimental setup has been developed based on a Langmuir-Blodgett (L-B) trough. The modified trough allowed introducing an air bubble beneath the particle monolayer formed at the air-water interface which made the study of the interaction between the bubble and the monolayer under various pH values possible. The monolayer characteristics of the particles were also studied and compared in terms of surface pressure (?-A) isotherms and packing factor. On compression, the particles formed branched structure at high pH whereas a uniform monolayer was formed at lower pH. Observations related to the behavior of particles during compression and expansion cycles, and the coalescence of a bare bubble with the flat particle laden interface were provided and the implication of the results for flotation process was discussed.INTRODUCTIONFroth flotation is known for its versatility and ability to concentrate low-grade, complex ores. It is considered a physico-chemical process in which particles attach to air bubbles, depending on their hydrophobicity as well as other factors, and are carried to the surface to form a froth layer. Reagents are used to stabilize bubbles and the froth layer (Pugh, 1996). However, particles, which are carried by the bubbles or entrained, significantly contribute to the stability of the froth phase (Ata et al., 2003; Zanin et al., 2009; Bournival et al., 2015a). Their relevance in mineral processing has led to a number of fundamental studies on the effect of particles and their properties on the process of froth flotation.Flotation systems are particularly difficult to characterize due to the broad range of properties of particles (e.g. size, liberation, hydrophobicity, etc.) and inconsistent operational conditions (e.g. changes in water quality, reagent addition, etc.). Several studies have made the use of well characterized particles in laboratory conditions. Such studies allowed the finding of an optimal contact angle for the stabilization of the froth phase (Johansson and Pugh, 1992; Ata et al., 2002). Froths have a large number of bubbles so that individual interactions are not observed. The study of two bubbles allows to determine the stability of the bubbles, with particles, and to some extend the stability of the bubble-particle aggregate (Gourram-Badri et al., 1997; Bournival et al., 2015b). The removing of particles between two bubbles may also be studied from a Scheludko cell (Johansson and Pugh, 1992) or by observing a bubble with a flat interface (Sethumadhavan et al., 2002). However, these systems provide limited information on the arrangement of the particles."

Jan 1, 2018

By I. V. Shadrunova

Annually it is formed more than 95 Mt of clinkers in iron and steel industry of Russia, including 79 Mt of clinkers in blast-furnace, steelmaking, foundry and ferroalloy productions. Complex development of clinkers will provide not only extraction of valuable components, but also preservation of ecosystems. Processing of solid slags is realized, as a rule, in a cold condition by mechanical methods only including stage-by-stage crushing of slag on devices, working on principles of compression and shift (jaw and roll crushers). However it doesn?t provide the complete extraction of metals from clinkers. The intensification of decomposition, in our opinion, can be provided under the use of the devices working on a principle of free kick. At such influence on a material, its destruction occurs on micro cracks, sides of cohesion that is there is a selective destruction of the components possessing various resistances to impact. Decomposition of a piece on the basis of free kick about a material or metal is realized in centrifugal-shock crushers and mills of research-and-production association ?Ural Center?. The share of the joints sharply lowering the efficiency of enrichment thus is minimal. The efficiency of application is proved by morph-metrical measurements with the help of system of image analysis ?SIAMS-600? and physical-mechanical tests of clinkers and their components (impact strength, micro hardness). The experience of application the devices of centrifugal-shock crushing for processing clinkers in blast-furnace, martin and converter productions of Open Society MMC, clinkers of rough-edged copper melt of Joint-Stock Company "Karabashmed" and aluminium clinkers of Joint-Stock Company « Samara plant of aluminium alloys » has allowed to confirm the efficiency of application these devices for selective decomposition of metallurgical clinkers and the opportunity of using clinkers as resource of ferrous and nonferrous metallurgy.

Jan 1, 2014

By Atul Kumar Bhatnagar

TATA STEEL is the pioneer in coal beneficiation in India. The first coal beneficiation plant was set up in 1951 at West Bokaro and subsequently in 1953 in Jharia. Over the years more beneficiation capacity was added by setting up new coal washeries in both West Bokaro and Jharia, the coal divisions of Tata Steel. currently the beneficiation capacity available is 8.5 mtp aappx Being a captive supplier supplying the coking coal as per demands of our steel works is challenging in the sense that the intent is to leverage the captive raw material advantage and select the best strategy for maximizing value up to steel making. The beneficiation plants were designed to produce clean coal up to 17% ash. With the demand of increasing productivity at the blast furnace the clean coal ash was lowered. subsequently the processes were audited and efficiency improved. The next challenge was to improve the throughputs in the existing plants to maximize the clean coal production. The upgradation was designed in house and implemented to upgrade the plant from nameplate capacity of 2.1 mtpa to 4.5 mtpa while the yearly production targets were also achieved. The presentation will detail the different phases of improvements, process followed, challenges faced, and the results as achieved in the process. Keywords: coal beneficiation, India, coal washeries, beneficiation plants XXVI INTERNATIONAL

Sep 1, 2012

By Diogo R. Prado, José Aurélio M. da Luz

Drying operation can have a major importance in a mineral processing undertaking. The proper sizing of dryers can ensure the specified dewatering level without energy wastage. However, often the sizing of fluidized bed is done disregarding the actual residence time distribution (RTD) of the particles inside the reactor. In this case it is usual to adopt the average residence time as a design criterion. In this work, we have quantified the effect of residence time distribution on drying, ensuring that a previously adopted fraction of the particles remains inside the reactor for the required time lapse needed for drying. Design criteria such as particulate flow rate and drying time, taking into account the statistical distribution of residence time was studied, matching the thermodynamic and fluid dynamic aspects of the drying process. Experimental tests carried out have confirmed the RTD for a teetering bed as the same for a canonical ideal mixing system. Although the fluidized bed volume using the proposed formulation was higher than that found for the average time based procedure, the efficiency gain in drying has proven advantageous.

Jan 1, 2014

By V. A. Vorob'ev, A. N. Larionov, E. N. Ivanov, M. A. Ryazanov

The aim of the research is to increase the recoverable value of poor, difficult-to-digest complex mineral raw materials. In the Republic Belarus, universal centrifugal-shock devices have been created for crushing, grinding and classification of ore and non-metallic mineral raw materials in dry mode, which differ from foreign analogues by a higher level of resource saving (including electricity and materials). Dry-ore preparation technologies have been tested on a pilot scale: fine crushing (replacing grinding in rod mills), grinding (replacing wet grinding in ball mills) and pneumoclassification on different types of ores, - which made it possible to identify the criteria for the suitability and unsuitability of mineral raw materials for their use. The possibility of regulating the upper and lower limit of the size of the finished material is established, the possibility of reducing the yield of slimes (-0,020 mm) to 5 times is determined. A comparative analysis of the contrast degree of separation characteristics of ore a similar granulometric composition, crushed in wet and dry conditions, is performed. The achieved contrast degree of gravity properties after dry grinding - 104,3; after the wet - 60.2. When enriching on a centrifugal concentrator, gold recovery to the concentrate after dry grinding increased by 13.12% while improving the quality of the concentrate from 78.3 g/t gold to 90.75 g/t. When testing the gravity-flotation scheme for the enrichment of poor gold-quartz ore, the increment of gold extraction after dry grinding was 7.6% for gravity and 9.5% for flotation; the total increase in extraction is 17.1%. The possibility of flotation of a larger material after dry grinding has been proved, with an extraction gain of 1.5% compared to the flotation of thinner material after ball milling. The influence of dry technology on the efficiency of the leaching of gold and silver (an extraction gain of 5.5 to 10%) and heap leaching (extraction gain - up to 18.3%) was studied. The positive influence of dry ore preparation technologies on the efficiency of gold and silver heap leaching and heap leaching, thickening and filtration is proved. Lines of dry ore preparation technologies can be used in modular complexes for processing technogenic raw materials.

Jan 1, 2018

By Sarthak Kaushik

Zeta potential measurements show that the isoelectric point of crandallite, in aqueous solution of 10-2 N sodium chloride is at about pH 5.5. Measurements of turbidity confirm the point of zero charge or crandallite. Calcium ions specifically adsorbed on the surface and thus changed the zeta potential and turbidity. From the measured data, it is confirmed that starch acts as a flocculent for crandallite. Oleic acid, which is a collector used in phosphate ore processing is weakly adsorbed on the surface of crandallite. This results in hydrophobic coagulation of particles resulting in a lower turbidity.

Sep 1, 2012

With shortage of sulfide nickel ores, laterite ore was paid more attention by scientists. Because its grade is commonly lower than sulfide nickel ores, laterite ore can not be utilized effectively be-coming the bottleneck of study. Leaching laterite ores from Yuanjing, Yunnan province, organic ac-ids show better selective than sulfide acid in nickel and cobalt recovery. Organic acid has low de-pendent on pH, keeping leaching capability even higher than 3. On the other side, when pH up to 2, sulfide acid can not leach laterite ores any more. After four kinds of organic acid leaching laterite ores, besides citrate, malate and succinate have good leaching and effectively selective capability. Especially, succinate has the best selective leaching capability of nickel and cobalt in four kinds of organic acids for latter anion purification and separation. Isolated from waste water with sugar, Aspergillus niger (zs1) has great capability to produce organic acids and vigorous growth. Laterite ores have been respectively processed by direct-leaching and indirect-leaching. Indirect-leaching gives a better result than direct-leaching. Extraction of nick-el by indirect-leaching reaches 44.3%, far more than that of direct-leaching. Moreover extraction of nickel at pulp density of 5% is higher than that at pulp density of 10%, reaching 63% in 11 days and extraction of cobalt also is 48.1% in the same period. Compared with nickel and cobalt, iron gives low extraction in solution, containing organic acids produced by Aspergillus niger .

Jan 1, 2014

By Richard K. Komarek, Antonios Zavaliangos, Roman T. Dec

Roller presses are widely utilized in mineral industry for fine milling and compaction. Recently used models are providing only limited information about the material behavior in the roll bite. This paper introduces a 2-dimensional finite element model for analyzing those two basic processes. A pressure-dependent plasticity model with linear elasticity was used as a constitutive model for the particular material. Coulomb friction law was used to describe phenomena on the material/roller surface interface. Two basic roller geometries are considered: smooth (used for milling and compaction) and with cavities, commonly used for briquetting. Comparison of the results obtained from the model with experiment indicates that they are following the general trends of experimental values recorded with laboratory roller presses. It is shown, that the model is suitable to analyze material behavior through all stages of the rolling process: feeding zone, nip region, neutral plane and release section. It can predict pressure, shear stress, slip of the material over the roller surface, material velocity field, failure of the compact during release and the course of other important process variables. This allows the process engineer to gain an improved understanding, leading to a better process and equipment design and control.

Jan 1, 2003

By V. Ross

"The Upper Group 2 (UG2) reef in the Bushveld Complex in South Africa hosts an estimated 40% of the world’s Platinum Group Metal (PGM) resources. The processing of this ore via flotation poses two particular challenges: limiting the levels of chromite in the concentrate to reduce downstream smelting problems, and enhancing the recovery of ultrafine (typically -10 micron), liberated PGMs. Conventional ways of suppressing the entrained chromite, such as froth washing, is not effective in PGM operations, which are dominated by mechanical cells. The recovery of fine particles is hampered by low collision efficiencies with air bubbles, as well as oxidised surface layers especially in tailings operations. This paper documents the results of laboratory tests on a run-of-mine PGM UG2 ore, investigating the application of a pneumo-mechanical column (PMC) and its effect on PGM flotation and its selectivity with regard to chromite. A key feature of the device is the stage-wise release of aerated slurry from an agitated downcomer, thus creating conditions where the superficial velocity profiles of air and slurry change axially within the separation zone. This aids segregation of the silicates and chromite-rich fractions in the separation zone, concentrating the latter towards the bottom of the column and minimising its entrainment into the concentrate. Comparison of the performance of the PMC to that of mechanical laboratory cells under equivalent operating conditions showed improved PGM flotation kinetics and recovery. This was accompanied by a decrease in gangue recovery compared to the mechanical cells by more than 40%, thus doubling the final rougher concentrate grade from 50 to 100 g/t. Significantly, whilst the overall Cr2O3 recovery was reduced by more than 60%, the selectivity (PGM recovery vs Cr2O3 grade in the concentrate) was doubled.INTRODUCTIONThe Bushveld complex in the northern part of South Africa hosts the world’s largest reserves of Platinum Group Metals (PGMs), representing approximately 40% of the total PGE. It is characterised by three main PGM bearing reefs, namely Merensky, Upper Group 2 (UG2) and the Platreef. The Merensky and Platreef are dominated by silicates in the form of pyroxenites, and carry economically recoverable amounts of copper and nickel, in the form of chalcopyrite and pentlandite. The UG2 on the other hand is a chromitite ore with chromite as (ideally, FeO.Cr2O3) the most abundant gangue, often constituting more than 70% by mass with a PGM grade of around 4.5 g/t. Other key gangue minerals are pyroxene, feldspar and talc. The PGEs occur in a wide variety of minerals, with platinum and palladium sulphides typically accounting for about half of the total. Base metal sulphides such as chalcopyrite, pentlandite and pyrrhotite occur in only very minor amounts, accounting mostly for less than 0.1% by mass."

Jan 1, 2018

By John A. Herbst

Professor A.M. Gaudin and his students at MIT were dedicated to understanding the fundamentals of mineral processing and as a consequence were constantly searching for better quantatative descriptions of size reduction, liberation and mineral separations. I have had the good fortune of meeting Professor Gaudin and working with many the modeling pioneers who followed him. I have observed first hand the refinement of mineral processing models as they increased in realisticness moving up the steps of the pyramid (see figure below) from pure empiricism to the current pinacle of physics based models. During this journey our industry benefited significanbtly as model prediction errors were reduced from ± 20% to ± 1%. Unit operation and plant simulations improved in accuracy and speed of calculations.

Sep 1, 2012

By M. L. Torem, R. H. Rojas, A. G. Merma

"Fine particle recovery by conventional flotation processes is very low mainly due to the low probability of bubble/particle collision and adhesion. In order to solve the problem of low particle recovery, several flotation technologies have been developed to increase bubble/particle collision efficiency. Among these technologies, the electroflotation process stands out. This process has advantages in the generation of microbubbles (<100 µm) and in the production of different amounts of hydrogen and oxygen microbubbles. These advantages favorably influence the fine particle floatability, due to the greater probability of particle/bubble collision and adhesion. The electroflotation tests were conducted for a hematite/sodium oleate system in a Partridge-Smith modified electroflotation binary cell of 0.38 L usable volume. The sodium oleate concentration, particle size, pH and current density were evaluated. Satisfactory results in the recovery of hematite were found at pH values of 7, reaching hematite floatability of 99% and 90% with hydrogen and oxygen bubbles, respectively.INTRODUCTIONThe flotation recovery of fine and ultrafine particles is normally very low and is caused by several factors, among them, the low probability of collision and adhesion bubble-particle, the difficulty to overcome the energy barrier (entrainment and entrapment), low selectivity, surface oxidation and mineralogical changes (Schulze et al., 1989; Waters et al., 2008; Shahbazi et al., 2010). This problem can be overcome by decreasing the bubble size or by increasing the apparent particle size. However, it is worth noting that the use of small bubbles or micro bubbles also involves some disadvantages such as their low momentum resulting in a slower process comparing with conventional flotation. Electroflotation is an attractive alternative for treating fine particles with small bubbles less than 100 µm, generated by the electrolysis of water. Electroflotation is one of the variants of the flotation process, where the gaseous phase is produced by electrolysis of an aqueous solution, generating oxygen and hydrogen bubbles (Sarkar, 2010; Gupta and Ali, 2012). These smaller size bubbles allow the recovery of fine particles by increasing the collision efficiency. This process is versatile and competitive in relation to other techniques such as dissolved air flotation and dispersed air flotation because the electroflotation units are smaller, more compact and require less maintenance and less operating cost than other flotation units (Zouboulis and Matis, 1995,). In addition, the electroflotation process is a clean technique and provides results in a short time, requiring only the investment in the electroflotation cell construction stage and the choice of the electrodes (Ketkar et al., 1991; Sarkar et al., 2010; Sun et al., 2011). In this sense, this study assesses the effect of pH, particle size and sodium oleate concentration on electroflotation of hematite fines."

Jan 1, 2018

By P. K. Fedotov

Centrifugal separation opens its new application fields in the Mining Industry. The up-to-date equipment for ultra-fine ore and concentrates grinding allows an efficient use of centrifugal concentration for micronic gold grains recovery. Moreover, advanced centrifugal concentrators are presented on the market: concentrators with continuous concentrate discharge designed both for ore and non-metallic minerals concentration process. The conducted tests proved the centrifugal concentration to be efficient process for gold recovery from finely ground concentrates and ores (less than 20 µm). Knelson concentrator application for such a fine material in different process circuits makes possible to raise the total gold recovery level of plants. In the circuits of coal plants and in course of coal slimes treatment the centrifugal concentration may be used before flotation in order to improve process performances. A centrifugal concentrator KC-CVD with continuous concentrate discharge working on 0.3 (0.5)mm fraction before flotation is

Jan 1, 2014

By R. Chowdhury

Axis House manufactures and supplies alkylhydroxamate reagent of various carbon chain lengths for application in flotation of oxide copper and other minerals. As part of reagent performance improvement the structural factors of hydroxamate are examined by various analytical tools in particular with X-ray diffraction of single crystals. In a recent publication, the structure of n-octylhydroxamic acid and its corresponding potassium salt are presented with findings of hydroxamic functional group geometric preference, H-bonding, keto-enol tautomerisation, acid-salt aggregation and alignment of carbon chain. In this paper an example of branched alkylhydroxamate 3, 5, 5-trimethylhexylhydroxamate will be presented and compared with the result of linear alkylhydroxamate.

Sep 1, 2012

By Deirdre Bradshaw, Cornelius Vos

"The detailed understanding of the variability in process performance parameters within an ore body forms a key aspect of ensuring that proper decisions are made with regards to the economic viability of that ore body. To gain this understanding, various tools have been developed over the years, of which the batch flotation test is the most well-known and applied technique for investigating the flotation separation of ores. In this paper, the Julius Kruttschnitt Mineral Separability Indicator (JKMSI) is put forward as a small-scale test, suitable for the characterization of the flotation separability of copper porphyry ores. It is demonstrated that the JKMSI can be a complementary technique to the batch flotation test, with the capability to further improve the knowledge of ore body variability. The response from this test has been shown to be sensitive to particle size and modal mineralogy, providing a critical link between flotation and upstream comminution activities. The trade-off between the fineness of grind and the recovery target can thus be evaluated to determine the minimum energy application required for optimal separation economics. The test is designed to utilize small sample quantities of various sizes, providing an opportunity to increase our understanding of ore variability through increased tests. This complements our ore body knowledge and combining this with efforts in comminution (Powell, 2013) provides a platform for extending the concept of flexible circuit design."

Jan 1, 2014

By L. Kuzev

Unknown and unpopular vibrational grinding mills possibilities to horizontal working chambers have been discussed. They can be realized under normal conditions with the typical values of vibrations applied with vibrational grinding which are: vibration frequency from 15 Hz to 50 Hz, vibration amplitude to 6 mm and vibration geometry. These possibilities constantly increase involving new raw materials and processes. Vibration grinding is possible with other technological process accompanied by intensified technological processing, while the process decreases. In many cases these technological decisions are original.

Jan 1, 2014

By G. J. Feng

Based on detailed theoretical analysis of coarse floatation and three-phase froth, a laboratory system which contains a new type of froth floatation equipment is established. Through water experiment, the relationship among floatation dynamics parameters of the equipment is studied and the best work parameters are educed too. Based on all of above, Slurry test is carried out in a copper concentration plant. Granule between 0.28~0.45mm can be reclaimed successfully. The slurry test proves that to separate coarse minerals in froth floatation equipment is a kind of effective method, it is well worth to make a further study.

Jan 1, 2014