Search Documents

Electrochemical behaviors of synthetic and natural enargite in buffer solutions have been investigated using open circuit potential, stationary polarization and cyclic voltammetry as functions of solution pH, scan direction, scan range, scan rate and dissolved O2. The results indicate that the electrochemical behaviors of synthetic and natural enargite are very similar; solution pH, scan direction, scan range and scan rate have remarkable effects on the electrochemical behavior of enargite while dissolved O2 has little effect on the electrochemical behavior of enargite. The potential range in which enargite possesses the ability of passivation is from ?0.9 V to + 0.83 V vs. SCE. Enargite is most stable in neutral and alkaline solution around potential ?0.2 V vs. SCE. The main oxidation products on enargite surface in alkaline solution are Cu(OH)2 while the potential imposed on it is within the range of ?0.2 V to 0.33 V vs. SCE and Cu(OH)2 + S0while the potential applied is higher than 0.52 V vs. SCE.

Jan 1, 2014

By Y. F. Guo

Laboratory scale experiments were conducted to produce titanium-rich material from Panzhihua ilmenite. The results showed preoxidation with sodium salt additive especially for Na2B4O7 signif- icantly advance the reduction of iron in Panzhihua ilmenite. Acceleration mechanism of preoxidation with Na2B4O7 has been studied here. The maximum metallization of iron 92% can be obtained under conditions of preoxidation at 850? for 30 min and subsequent reduction at 1100? for 150 min. The rusting separation technique to reduced ilmenite has been further studied, obtaining titanium-rich product with TiO2 over 82% and the recovery of TiO2 above 97%.

Jan 1, 2014

By O. A. Bascur

It is difficult to analyse the economics without an integrated view of mine transactions, stockpile inventories, process flows and assays. The lack of integration of mining and metallurgical information with sufficient detail to analyse and act is a problem. However, to take action requires real time information from manufacturing assets, corrected for gross errors from trucks, shovels, conveyors, faulty sensors, bad instrument calibration. Validation methods use process models to identify inconsistent information in the case of corrupt actionable information. This paper presents new strategies that transform the data into business information for continuous improvement and optimization. This technical presentation will review recent implementations enabling large metallurgical complexes to improve their data quality for overall production and energy management. A competence center emerges as an enabler for implementing operational intelligence. The evolution of Web services to troubleshoot plant information and to collaborate at the enterprise level is presented.

Jan 1, 2014

By H. J. Wu

The optimum performance in mineral processing plants usually demands the optimum size reduction, which is frequently achieved by a closed grinding circuit. Due to the difficulty associated with fine size classification, the size separation efficiency in closed grinding circuit is usually very low, which leads to huge circulating load and significant overgrinding. Recent development of Der-rick Stack Sizer has made an efficient fine size separation down to 200 mesh with a satisfactory screening capacity. With the efficient fine size separation with Derrick Stack sizer, the problems commonly associated with typical closed grinding circuit, including high circulating load and over-grinding, have been eliminated. Feedback from numerous Stack Sizer applications in iron ore industry indicated that, compared with conventional fine size classification equipment, the circulating load achieved by Derrick screen was usually decreased from approximate 300% down to 60% or so, while the iron recovery has been increased by 6% to 8% only by more efficient size separation in the closed grinding circuit. To study this phenomenon, this paper discusses the relationship between size classification, circulating load and mineral recovery in the closed grinding circuit. A simulation model to predict the improvement in the grinding circuit from more efficient screening is also introduced with this paper.

Jan 1, 2014

By D. Hatfield, G. de Jager

"The rapid developments in computer vision and computational resources are creating new possibilities for the use of machine vision systems for industrial control. A number of commercial image analysis systems exist, and research into improved measurements of froth performance is ongoing. An integral part of the implementation of these systems is the validation of the relationship between image analysis measurements and flotation cell performance. This paper discusses the factors affecting concentrate flow and presents the results obtained from one such system with respect to its ability to estimate the flow of concentrate from a flotation cell.The relationship between froth flow speed and the rate of recovery of concentrate from a flotation cell was investigated on two industrial operations, both processing PGM (Platinum Group Metal) bearing ores. Results are presented that show a relationship between froth flow speed and concentrate yield."

Jan 1, 2003

The ever increasing demand for energy and the progressive depletion of crude oil resources, have renewed interest in oil shale as an alternative fuel resource. Weathered oil shale samples were assembled from El-Nakheil phosphate mine in Quseir area, Eastern desert, Egypt. The oil shale samples were prepared and analyzed by XRD (X-ray diffraction), XRF (X-ray fluorescence spectrometry), and optical microscopic techniques. Rock-Eval pyrolysis and total organic carbon were used to study shale hydrocarbon potential. A leaching procedure using inorganic and organic acids was used to selectively dissolve the oil shale associated ash forming minerals. XRD results showed that calcite is the dominant carbonate mineral, whereas primary silicate minerals are quartz and montmorillonite. SEM (Scanning Electron Microscopy) observations indicated that the organic matter is dispersed throughout the rock matrix. The acid soluble fraction upon leaching was determined to be 37.59 and 42.74 wt% by using 5% HCl and 10% HCl, respectively. The TOC was increased from 20.78 to 29.88 and 34.09 wt% by using 5% HCl and 10% HCl, respectively. Keywords: el nakheil oil shale, characterization, xrd, xrf, sem, elemental analysis, proximate analysis, ultimate analysis, thin section, rock eval pyrolysis, acid leaching

Sep 1, 2012

By W. X. Yin

Electrowinning of lead from aqueous solution of PbCl2 and electrowinning of manganese dioxide from aqueous solution of MnCl2 are two research focuses in hydrometallurgy. This paper investigated a new process of simultaneous electrowinning of lead and manganese dioxide in chloride medium. The simultaneous electrowinning process in chloride solution not only can prevent chloride from liberating at anodes but also obtain two electrolysis products and decrease electric energy consumption. Diaphragm cell is used in the simultaneous electrowinning process to form separate anode and cathode compartment. The effects of temperature, HCl concentration in anolyte, NaCl concentration in catholyte and electrolysis time on current efficiency and cell voltage are studied. The results indicate that current efficiency of anode and cathode for 5 hours is 99% and 96% respectively, average cell voltage is 1. 701V, the weight ratio of lead and manganese dioxide produced at electrodes is 2. 39:1 under the optimum conditions. As anode products, manganese dioxide is ??MnO2, content of which in the products is more than 92%.

Jan 1, 2014

Under the AMIRA P9 project the three-product cyclone-an off-shoot of the conventional hydro-cyclone-that produces three distinct products has been developed. The three-product cyclone shows great promise as a classifier in mineral processing. Industrial and pilot plant trials performed to assess its performance in the classification of the UG2 platinum ore, indicate that the presence of an extra overflow product stream that captures the mid-sized particles, provides improved classification efficiency. To assess the split on component density, samples from the feed and product streams were screened and assays by size for chromite (? = 4.8) and silica (? = 2.65) were obtained. Results from tests performed using this type of hydrocyclone in a number of applications indicates that it can be applied successfully in circuit configurations where the conventional hydrocyc-lone is not suitable. Utilising the three-product cyclone to classify the UG2 platinum ore resulted in an intermediate overflow product stream containing the mid-sized low density silicates and relatively fine high density chromite particles while the finer overflow contained mostly fine silicates and chromite particles. The coarse chromite and silicates reported to the underflow. Due to the increased number of products, the method of using efficiency curves was extended to cater for the increased number of products in the three-product cyclone. Although significant differences in the classification performance of the three-product cyclone were noticed with variations in machine variables a consistent method of assessing the performance was applied. The efficiency curve was adopted and applied and separate efficiency curve properties were obtained for each product stream. The methodology was applied to the component data, and efficiency curve proper-ties for each key component were obtained and compared. This paper discusses the application of the efficiency curve to cyclones producing more than two products and extending the methodology to the different components in the feed.

Jan 1, 2014

By Y. G. Zhu, G. B. Zheng, Z. B. Qian, X. R. Zhang, A. J. Ren

"Based on PMA polymer, two kinds of novel macromolecular depressants, PMTA and PMA-PDTC, were designed and synthesized. PMTA was used for desilication in hematite reverse flotation. PMA-PDTC was used in the separation of Cu-Pb concentrate as galena depressant. The micro-flotation results showed that PMTA exhibited a good depression performance compared to starch. We found that 98.29% of hematite was depressed with a grade of 65.24% at pH 11 with 12 mg/L dosage. The flotation separation results of Cu-Pb concentrate demonstrated that PMA-PDTC was an effective depressant for galena in separating galena from chalcopyrite. When IPETC was used as collector, at pH 8.5, the flotation separation tests demonstrated that Cu concentrate was obtained with a grade of 28.89% containing 12.12% Pb.INTRODUCTIONThe role of depressants is crucial in the separation of oxide or sulfide minerals, for example, the desilication in hematite concentrate and the separation of Cu-Pb concentrate.It is well known that, in current reverse flotation processing of hematite, starch is a traditional depressant for hematite. Most research focus on the modification of starch [1-3]. Although its depressing ability is enhanced in some extent, its own shortcomings is still existed. So, it is important to develop a new hematite depressant instead of starch.In the separation of chalcopyrite and galena, because of their extremely similar floatability, it is difficult to realize the separation of these two minerals. Traditionally, there are two methods widely used in the separation of Cu-Pb concentrate by depressing chalcopyrite with cyanide [4] or depressing galena with dichromate [5] in most cases. However, these two inorganic depressants are toxic and hazardous. Their use could cause heavy pollution problems and a large loss of precious metals. In order to adapt to the requirements of sustainable economic development and environmental protection, the research and development of green and environmental depressant has gained more and more significance."

Jan 1, 2018

By P. K. Rozakeas

It has been experimentally demonstrated that the application of electrokinetic techniques in the continuous flow of coal-water suspensions within a helical anode-cathode pipe geometry effectively causes a significant reduction in the wall shear stress. This reduction in the frictional force at the cathodic pipe wall surface is attributed to a decrease in the concentration of coal particles in this flow region caused by the migration of negatively charged coal particles towards the anodic surface(s). The disadvantage of flow-intrusive geometries is the reduction in effective flow area as well as an increase in frictional surface area caused by the placement of the anode(s) within the flow region. Experimental data is presented for a non-intrusive helical anode-cathode geometry embedded in the pipe wall which shows that a reduction in pumping energy of approximately an order of magnitude is possible. A sample of sub-bituminous black coal fines having a mean particle size of approximately 17 microns was used to prepare coal-water suspensions with a solids concentration of 50%(w/w). The practical and economic implications of this work relate to an enhanced method of long distance transportation of slurries in pipes as well as an alternative technique for continuously separating solid-liquid suspensions.

Jan 1, 2014

By Carlos G. Rudolp, Julio C. Videla, Mario Zuleta

"The present paper summarises the results of gravity pneumatic concentration of a borax ore with 17.5 % B2O3. The sample was extracted from the Tincalayu ore deposit located in the Salta Province of Argentina.The applied methodology was based on a former study (Zuleta, 1985). It consisted of sample characterization by means of physical and mineralogical determinations, chemical analyses as well as pneumatic table concentration tests. In this, a simplified concentrating flowsheet was utilized.A concentrate with 30.6 % B2O3 and 74.7 % recovery was obtained. The recovery was 8.8 % less than previously reported and that was of 30.6 % B2O3 with 87 % recovery. Nevertheless, the simplified flow sheet presented processes only two granulometric fractions, - 6.4 mm + 0.3 mm and - 0.3 mm, compared to the three granulometric fractions used in the previous study: - 6.4 mm + 1.4 mm; - 1.4 mm + 0.3 mm and . 0.3 mm. This would simplify industrial implementation."

Jan 1, 2003

By B. Das

Waste water produced from coal preparation plants posses several problems during dewatering and solid/liquid separation. The natural sedimentation rate of the particles present in colloidal and finely divided suspended form is very slow. Flocculation technology is being applied in most of the coal washeries to recover water which is being accomplished through the use of inorganic salts, polymeric flocculants or both depending on the chemical and physical characteristics of the pollutants present in the waste water. The waste tailing water from Piperware coal preparation plant, Central Coalfield Limited (CCL), India, is highly turbid containing ~ 16000 NTU with negative surface charge in the pH range of 2 to 10. Polymeric flocculants in conjunction with fine magnetite is investigated to achieve faster settling rate with lowest level of water turbidity. The conditions affecting the interaction between the reagents and the turbid particles present in the tailings water are investigated. It is possible to bring down the turbidity of the water to < 90 NTU from very high turbid tailing water by using 2 mg/L of the polymeric flocculent in combination with 0.1 g/L of magnetite at natural pH of the tailing slurry. It has been found that finely divided positively charged magnetite particles in combination with the flocculent selectively coat the negatively charged impurities present in water and thereby increase the settling rate under the influence of a magnetic field.

Jan 1, 2014

By G. Y. Zhou

During Zijinshan copper heap bioleaching, pyrite was leached in plenty resulting in high ferric concentration in solution. It has affected bioleaching and extraction processing greatly. It results much acid and iron in solution and bad effect to extraction processing. The paper studied the influence factors in the course of pyrite leaching and ferric ion chemical oxidation, especially studied the redox potential for copper bioleaching so as to find key factors affecting the dissolution difference between chalcocite and pyrite. The results show that the redox potential is important factor. Copper and pyrite leaching rates are 95% and 11% respectively and there is great dissolution difference between them at redox potential 700 mV (SHE). During pyrite bioleaching, the indirect action of bacteria gives priority to bioleaching cooperating with the direct attack of microbial cells attached to the mineral surface. Redox potential is determined by ratio of ferric and ferrous, ferric in solution was supplied by the way of oxidation of T. f bacteria, sufficient bacteria concentration and active character were two vial factors of controlling redox potential. It is indicated that copper can be selectively bioleached during copper bioleaching by controlling redox potential of bioleaching. The conclusion will provide theoretic foundation on balance of acid and iron during bioleaching for copper of higher S/Cu ratio. The experinment proved that bacteria activation was decreased on condition of both low pH value and intermittent aeratation during bioleaching. It resulted that the oxidation velocity of ferrous ion was decreased and redox potential was controlled. The dissolution of pyrite was depressed. It would be possible to actualize selective leaching of secondary sulfide copper ore during bioleaching process.

Jan 1, 2014

By M. M. Bugarin, P. J. van Staden, V. T. Conic, S. S. Dragulovic, R. M. Kovacevic, D. B. Milanovic

"The mineralogical and physico-chemical characteristics of a polymetallic sample from a mine of West Serbia suggest that it can be classified as a SEDEX type of ore. Those ores contain multiple value components, being inter-dispersed as fine grained aggregates. This prevents concentration by gravity or flotation concentration processes. Mineralogically, the valuable metals (Cu;Zn;Pb;Au and Ag) occur as pyrite, sphalerite, galena, tetrahedrite, chalcopyrite, covellite, arsenopyrite, and non-metallic minerals (barite, and waste minerals). Novel technologies are under development within this project for the recovery of all valuable metals from this very complex material. The work comprises the further treatment of solid residue obtained after Cu and Zn extraction by bioleaching, for the subsequent recovery of Pb and the precious metals Ag and Au. The residue is first treated with a saturated sodium chloride solution, whereupon a chloride solution of lead (NaPbCl3) is obtained. From the chloride solution, lead was deposited in the form of lead carbonate, followed by reductive melting, whereupon lead anode was obtained. Electrolytic refining of the lead anode, using a solution of PbCO3 in methane sulphonic acid (MSA-Methanesulfonic acid, min 99.5% CH4O3S, density 1.48 kg/dm3, Manufacturer: Carl Roth) as an electrolyte, yielded refined lead cathode. It should be noted that, after precipitation and separation of lead carbonate, the sodium chloride solution is restored to its original composition by the addition of make-up reagents and returned for another lead-sulfate leaching cycle. The solid residue obtained after leaching lead-sulphate, is leached in thiosulphate solution, with the addition of an activator, a catalyst and lixiviant for gold, to yield a thiosulphate solution of gold and silver. Since the content of gold and silver in solution is low (below 1 mg/dm3), they are first electrolytically concentrated on steel cathode and then refined to pure metals using well-known chemical methods. Note that, after the electrolytic separation of gold and silver, thiosulphate solution is recycled to the leaching step."

Jan 1, 2018

By S. K. Pan

The process flow-sheet adopted in treating hematite iron ore in India through wet circuit generates not only 15-25% slime of Run-of-Mine (ROM), but also results in loss of very high quality fine iron ore particles along with it. As the reserves of hematite iron ore is depleting, it is necessary to explore the possibility of upgrading other types of low grade iron ore and slime for recovery of iron minerals; extensive research in this field is being carried out. While beneficiation of low grade ore is yet to be established, slime beneficiation has been quite successful and many installations of slime treatment plant are underway. In SAIL mines, the slime is mainly the discarded particles from Classifiers, which are less than 0.2 mm sizes. R& D initiative has been focussed on the beneficiation of the slimes (49-60% Fe, 3-10% Al2O3 & 4-10% SiO2) of Dalli mines to generate concentrates assaying 62-64% Fe, 2-3% Al2O3, 3-4% SiO2 and a few innovative facilities for the same has been introduced at this mines of Bhilai Steel Plant (BSP). At Dalli mines, the slime is of very poor quality. A typical slime analysis assays 48.54% Fe, 15.1% SiO2, 8.5% Al2O3 and consists nearly 60% (by wt.) particles less than 38 micron. Slime analysis revealed substantial quantity of very high density mineral particles, those causes jamming of Thickener due to faster settling. A novel technique has been implemented to classify the concentrate ore particles from the gangue mineral particles by processing through Fluidized Bed Classifier (FBC) system, which is a gravity concentrator, to treat 50% of the slime generated and the rest is treated through de-sliming hydro-cyclone followed by Medium Intensity Magnetic Separator (MIMS). A special self-vibrating launder has been designed and introduced into the system to recover tiny iron ore particles, which could not get captured by the permanent Neodymium rare earth magnet in MIMS. The classified iron mineral particles from FBC are further treated in a battery of hydro-cyclones followed by modified Slow Speed Spiral Classifier (SSSC) unit. Multiple feed entry system to the SSSC unit is unique and use of particular feed entry point depends on the desired quality of the product and thus converted to a beneficiation equipment rather than mere de-watering unit. By processing slime in FBC system, the valuable iron ore particles with 62.5% Fe, 5.2% SiO2, 2.23% Al2O3 has been recovered from the slime at a material yield of 30%. And very high valued concentrate particles with more than 65% Fe has been sorted out through the magnetic separation route. The overall extra production of beneficiated slime concentrate is 40-45 tph with 63-64% Fe from a slime feed of 120-130 tph solid. This paper outlines few new approaches in iron ore slime beneficiation at Dalli mines for maximum recovery of valuable minerals. Keywords: fluidized bed classifier (fbc), iron ore slime of dalli mines, medium intensity magnetic separator, slow speed spiral classifier (sssc)

Sep 1, 2012

By R. B. Shu

A moderate thermophilic microorganisms, has been isolated (45?) from a typical sulphide mine in the region of Mo Jiang located in the southwest of China. The culture has been used to extract copper from chalcopyrite concentrates obtained from De Xing copper mine. The majority of experiments were carried out in 300mL Erlenmeyer flasks containing 150mL volumes of mineral suspension. Effects of some variable parameters such as solids concentration, pH and the concentrations of inorganic nutrients on the bioleaching of chalcopyrite obtained from De Xing copper mine were investigated. For a given concentrate the most important factor affecting the fractional copper extraction was the size of the mineral particles. The overall rate of leaching was found to be limited by the area of mineral surface. The attack started in cracks and genetic defects and finally reached the whole chalcopyrite surface. As a consequence of this, the ore showed strongly cracks. The additive of ferrous sulfate increases the bacteria activity, but did not improve chalcopyrite bioleaching. The results indicate that the nature and relative proportions of the various minerals present have been shown to be important factors.

Jan 1, 2014

By Michel Brissette, Shaheer Sanuri, Veroljub Mihajlovic

"The main purpose of geometallurgy is to improve the mine planning by mapping hardness and throughput into the mine block model using geostatistics to eliminate the large production fluctuations caused by the ore hardness variability coming from different parts of the pit. However, not all grinding testwork available commercially can be applied to geometallurgy because of large amount of sample required and the associated cost per test. Geometallurgy is now being used in designing grinding mill but as the mining project progress, the accuracy of engineering must improve from 30-35% during the scoping study to 10-15% at the bankable feasibility stage and less than 5% for Engineering Procurement and Construction Management. For SAG milling, the SAG Variability Test (SVT) is an abbreviated version of the standard SAGDesign test developed for this geometallurgical need. The same amount of ore than the original test is ground for three cycles into an open batch SAG test and then the SAG pinion energy is predicted to the standard end point of 80% passing 1.7 mm. For ball milling, a Bond Variability Test (BVT) was also developed using the SAG ground ore from the SVT. The Bond ball mill grindability (Gpb), corresponding to the average of the net grams per revolution from the last three cycles of the Bond test, is also predicted from the third cycle. The relative error for both the predicted SAG ore hardness (WSVT) and Bond Work Index on SAG Variability ground ore (Sv-BVI), in kWh/t, averaged 5.5% and 3.8% respectively compared to the SAGDesign testwork values and are within 7% and 10% respectively from plant benchmark and within 7% from the samples sent to all partner laboratories. Both tests can be continued to measure the true hardness necessary for mill sizing. This article discusses the development of these two new tests, SVT and BVT, their potential use and accuracies in any geometallurgical program."

Jan 1, 2014

By T. M. Bhatti

The main purpose of present study was to characterize the dissolution of uranium from low-grade black shale with indigenous isolated strain of Acidithiobacillus ferrooxidans (BSAF-01). The nature of shale is quartzite-schistose and contains uranium content of 0.005% U3O8 (50 ppm U3O8). Uranium is present in the tetravalent oxidation state (U4+) in the shale matrix. The main minerals identified are graphite, quartz, pyrite, mica minerals (phlogopite, biotite, sericite, and chlorite), microcline, K-feldspar and kerogen (hydrocarbon-compounds). Bacterial oxidation of pyrite was an acid-generating system and produced sulfuric acid and ferric sulfate during this biological phenomenon. A series of bioleaching experiments were conducted in shake flasks for leaching of uranium from black shale. The leaching experiments were performed at 50% pulp density using indigenous Fe- and S-oxidizing bacterium (Acidithiobacillus ferrooxidans). Bioleaching data revealed that about 90% ~ 95% U3O8 was leached out from black shale ore. Uranium dissolution from shale depends on pH (pH 1.5~1.9), redox potential (=500 mev) and the concentration of Fe2+ and Fe3+ ions in the leaching environment. The oxidative leaching of U4+ involves a redox reaction with Fe3+ as an oxidant and bacterial re-oxidation of Fe2+ in acidic leaching environment. Uranium leaching efficiency was attributed to the sulfuric acid and ferric sulfate production during bacterial oxidation of pyrite.

Jan 1, 2014

By M. Kadiyski, V. Stoyanova, E. Visariev, V. Stoilov

"The present study deals with copper losses in slag from copper smelting. Copper slag cooling at Aurubis Bulgaria is traditionally done in pits. A new type of slag-cooling is introduced in the site, involving cooling ladles. In a previous study, the ladle cooling process was studied in detail, showing an improvement in the recovery of copper in the slag after flotation. The main reason for better recovery of copper is the increased cooling time, which allows for the accumulation and aggregation of copper droplets. The effects of the newly introduced slag cooling process are studied using optical microscopy and scanning electron microscopy. Cooling in pits and in ladles is compared, based on copper droplet size, distribution and content. Specialized image processing software is employed on images taken with an optical microscope. The results are then compared with a similar technique, available in SEM software. The availability of phase-analysing image software in combination with electron dispersive X-ray spectroscopy makes it possible to study the morphological properties, distribution and chemical composition of the copper droplets. The obtained results confirm the initial conclusions about size, distribution and composition of the copper-bearing particles. A large amount of copper particles is examined showing an obvious increase in their size from pit- to ladle cooling. The results show an increase in the average size of the droplets, which doubles from pit-cooling to ladle-cooling. There is a well-pronounced tendency of decrease of the percentage of droplets in the smallest fraction (<5 µm) in the ladle-cooled slag. In addition, the number of droplets in the larger fractions increases, compared to the ones in the pit-cooled slags. It is believed, that the developed methodology for analysis provides a relatively quick and reliable solution for comparison of the cooling rates in the slag. INTRODUCTION In the process of copper smelting and converting, iron-silicate slags are produced that contain various amounts of dissolved and entrained copper. Different physical and chemical techniques are employed for the valorisation of the remaining metals in the slag – magnetic separation, leaching, roasting, flotation, etc. According to Gorai et al (2003), about 2.2 tons of slag is produced per ton of metal. In 2016, about 20 million tons of copper have been produced globally (www.icsg.org). At an average of 0.5 percent copper content after treatment, these slags contain more than two hundred thousand tons of copper which is lost due to inefficient processing."

Jan 1, 2018

By F. Q. Cheng

As the important potash, the product yield of KCl in winter is low and the resources waste is serious according to the deficiency of collectors, which can be used in this condition currently. This paper studied on the change of contact angle, turbidity, and flotation recovery of KCl particles when different chain lengths, ratios of amines were used as collectors in KCl flotation process to get a new mixed collector. The contact angle values of KCl crystal in its brine solution added different amine collectors were first measured by captive bubble method. The turbidity of brine solutions were then measured by the laboratory turbidimeter at room temperature when different amine collectors were contained. In the end micro-flotation experiment using mixed amine with fixed ratios and ODA as collectors respectively at 5 °C, 23 °C were performed. The results show when the ratio of the mixed amine is DDA- 20%, ODA-60%, C20-20%, the contact angle at KCl surface is the maximum and the hydrophobic state is best. Meanwhile the result of turbidity measurement indicates that the dispersion of mixed amine colloids is better than the ODA collector due to the addition of DDA, which plays the role of frother. The flotation results also prove that the mixed amine is not only fit for the KCl flotation at room temperature but also fit for its flotation at low temperature. This study provides strong technical support to extend the production time of potash business in Chaerhan areas in China.

Sep 1, 2012