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PL
Artykuł przedstawia proces budowy zakładów przeróbki mechanicznej i flotacji kopalni rudy miedzi w Wilkowie koło Złotoryi w latach 30. i 40. XX wieku. Wspomniany kompleks górniczy został wzniesiony na polecenie koncernu – Towarzystwo Górnicze Spadkobierców Georga Gieschego (Bergwerksgesellschaft Georg von Giesches Erben) z siedzibą we Wrocławiu. W artykule przytoczono sposób projektowania zakładu przeróbki mechanicznej i flotacji, rodzaje używanych maszyn oraz wszystkie etapy procesu flotacji. Ponadto uwzględniono powody budowy stawu osadowego i sposoby radzenia sobie ze szlamami poflotacyjnymi. Wyjaśniono również ile prawdopodobnie mogła kosztować realizacja całego przedsięwzięcia oraz omówiono przyczyny zlokalizowania kopalni w tym miejscu.
EN
The article presents the proces of creating a mechanical processing plant and flotation of the mining copper ore in Wilków near Złotoryja in the 30s and 40s of the twentieth century. The mining complex was built to the command of Bergwerksgesellschaft Georg von Giesches Erben based in Wrocław. The paper presents the way of designing a mechanical processing plant and flotation, the types of used machines and the all stages of the flotation process. In addition depicts the reasons for construction of an sedimentary pond and the ways of dealing with post-flotation slimes. Also explained probably total costs of this project and presents the reasons for locating the mine in this place.
EN
The flotation separation of barite from calcite using sodium dodecyl sulfate (SDS) as the collector and sodium silicate (SS) as the depressant has been concretely studied in this paper. The results show that SDS has high collecting ability for both barite and calcite and that the flotation separation of barite from calcite cannot be achieved by using SDS alone. The depressant sodium silicate has a selective depression effect on calcite by the control of the pulp pH at 9.0 in the presence of SDS. Through locked cycle tests, a concentrate containing 95.54% BaSO4 can be obtained from an actual ore containing 24.5% BaSO4, with a recovery of 86.11%. The zeta potential measurements, adsorption analysis and infrared spectrum studies reveal that the pre-adsorption of sodium silicate strongly favors the adsorption of SDS on the calcite surface and adversely affects SDS adsorption on the barite surface. This property is the reason for the selective depression of SS on calcite.
EN
This paper researched the influence of the polysaccharide polymer sodium alginate (SAG) on the depression of talc at a fixed room temperature about 25 °C through micro flotation and batch flotation experiments, zeta potential and contact angle measurements as well as infrared spectroscopy analysis. The flotation results displayed that the SAG had a significant influence on the flotation of talc but less influence on sulphide flotation. Compared with the depressant carboxymethyl cellulose (CMC) and guar gum, using of the SAG gave the highest copper recovery. It could not only eliminate a talc removal step, but also significantly decrease in the depressant consumption by half at least. Sodium alginate apparently adsorbs on the talc surface and promotes hydrophilization, as revealed by contact angle tests (contact angle decreased from 75 to 33° after treating with SAG). It is demonstrated that the SAG obviously absorbed at the surface of talc but rarely for chalcopyrite through the results of zeta potential measurements and infrared spectroscopy analysis.
EN
In this paper, tetrahydrofurfuryl-functionalized polystyrene nanoparticles (TFPNs) were evaluated as collectors in low-rank coal flotation. A series of TFPNs were prepared by immobilizing tetrahydrofurfuryl groups onto the surface of polystyrene nanoparticles (PNs), and further characterized in terms of their size, shape, surface charge and surface functionalization group concentration (SFGC). The coal flotation performance using TFPNs was compared to that using PNs and diesel oil (DO). The interaction mechanisms between TFPNs and low-rank coal were also discussed. The results show that TFPNs gave higher recovery than that given by PNs and DO. Smaller TFPNs were more effective flotation collectors. The recovery of TFPNs increased firstly and then decreased with SFGC. TFPNs can specifically deposit onto the low-rank coal particles with the hydrogen bonding function between tetrahydrofurfuryl groups and oxygen-containing functional groups, and promote low-rank coal flotation by increasing the hydrophobicity and roughness of coal particle surface with the adsorbed TFPNs. It was demonstrated that TFPNs introduced a new class of collectors for low rank coal flotation.
EN
Flotation tests of different size fractions of NaCl, KCl and KPF6   in their saturated aqueous solutions were performed in a 36 cm in height monobubble Hallimond tube. Also contact angle tests by means of sessile drops of saturated salt solution put on pressed discs of salts were carried out. The obtained sessile drop contact angles were equal to zero, pointing to a complete hydrophilicity (orthophilicity) of the investigated salts. In the case of NaCl and KCl, their orthohydrophilicity was confirmed by flotation tests and flotometric considerations because the entrainment factors, which take into account the maximum size of entrained particles and density of the salt as well as it solution, were similar to those of quartz and magnetite and equal to 0.11 mm. The entrainment factor for KPF6  was equal to 0.18 mm and was greater than that of NaCl and KCl indicating certain natural flotation of this salt caused by some flotational hydrophobicity called in this paper metahydrophobicity. The metahydrophobicity of KPF6   was confirmed by flotation results. In the case of KPF6   the maximum yields of the same size particles were the highest, even though the density of this salt was greater than that of NaCl and KCl. Also, the first order kinetic constants were always the greatest for KPF6. Further flotometeric calculation based on the balance of forces involved in flotation indicated that the estimated contact angle of KPF6   was about 8 º   assuming static flotation, and 7 º   for dynamic flotation, while for NaCl and KCl was below 5 º . It means that during flotation test orthohydrophilic NaCl and KCl are only entrained while for metahydrophobic KPF6   there is mostly entrainment and some flotation.
EN
Clean coal ash content, a prominent product index describing coal froth flotation, is difficult to be measured online. This constraint leads to a lack of timely guidance during operation and impedes the optimal operation of the coal flotation process. To solve this problem, considering the fluctuation of working conditions, the heterogeneity of raw coal and the variation of feed coal classes, an integrated estimation model of clean coal ash content for coal flotation based on model updating and multiple least squares support vector machines (LS-SVMs) is proposed. First, a single estimation model for a single class of coal based on LS-SVM is built, and the internal parameters are optimized by gravitational search algorithm (GSA). Second, the model updating strategy is designed to solve the problem of the decline in single model accuracy. Furthermore, a multiple LS-SVMs model formed by several single models for different classes of coal is studied along with the model switching mechanism to address the problem of model mismatch. Finally, an industrial experiment and evaluation are conducted. The mean relative error between the estimated and actual values is 3.32%, and the correlation coefficient is 0.9331. The estimation accuracy and adaptability of the integrated model can meet the industrial requirements.
EN
Flotation using sea water has been considered as a promising alternative to concentrate molybdenite (MoS2) under alkaline conditions due to scarcity of fresh water and increasingly strict regulations on the quality of discharged water. However, the MoS2  recovery with sea water during flotation has not been satisfactory, owing to the depressing effects from the hydrophilic metallic species onto MoS2  surface. This study combines experimental and theoretical studies of MoS2  flotation to investigate how the physicochemical properties of MoS2  vary with the addition of a dispersant, sodium hexametaphosphate (SHMP), and in sea and fresh water. Our experimental results show that the addition of SHMP during flotation has increased the recovery of MoS2, via reducing the adsorption of the hydrophilic metallic precipitation onto MoS2  surface. The DLVO calculation confirms that the addition of SHMP increases the floatability of MoS2  by dispersing the formed hydrophilic metallic precipitation (Mg(OH) 2  colloids) from the MoS2  surface, via reversing attraction force to repulsion force, thereby improving MoS2  flotation recovery.
EN
Low-rank coals are difficult to float using common hydrocarbon oily collectors, such as dodecane and diesel. In this investigation, a mixture of dodecane and n-valeraldehyde was used as a collector to enhance low-rank coal flotation. The changes of the contact angle and surface functional groups of low-rank coal were measured before and after different collectors’ adsorption to indicate its absorption mechanism. Surface tension of different collectors was also measured to identify its spreading performance. The results showed that the flotation performance using the mixture as a collector was much better than that using dodecane or n-valeraldehyde solely. When used the mixture of dodecane and n-valeraldehyde as collector, dodecane primarily covers the hydrophobic sites while n-valeraldehyde primarily covered the hydrophilic sites by hydrogen bond promoting adsorption of dodecane at these sites. There existed synergistic effect between dodecane and n-valeraldehyde. Additionally, n-valeraldehyde can reduce the surface tensions to improve the spreading performance of mixed collector on low-rank coal surface. The improvement both in adsorption and spreading was responsible for the enhancement of low-rank coal flotation by using the mixture.
EN
The effects of Pb(II) ions and Al(III) ions on the electro kinetic and flotation behavior of rutile were investigated by micro-flotation tests, zeta potential measurements and solution chemistry analysis. Micro-flotation results indicate that the Pb(II) ions can effectively improve the flotation recovery of rutile while the Al(III) ions significantly inhibit the flotation of rutile. Zeta potential measurements reveal that a collector styrene phosphoric acid (SPA) can adsorb on the rutile surface after the addition of Pb(II) ions, but hardly adsorb on the rutile surface after the addition of Al(III) ions. Pb(II) ions adsorb on the rutile surface in the form of Pb(OH)+ and Pb(OH)2(s), and the latter one is the main reason that activates rutile flotation. Al(III) ions adsorb on the rutile surface mainly in the form of Al(OH)3(s), which prevent the direct interaction between the rutile and the collector, resulting in a decrease of rutile flotation recovery.
EN
The sodium fatty acids were firstly prepared by fatty acids with different iodine values which were from surfactant extraction using soybean oil fatty acid as raw material in this study. Effects of iodine value of sodium fatty acids on the flotation of collophanite were then investigated by flotation tests, contact angle measurements, adsorption tests, Krafft point measurements, foaming ability tests, and the resistance to the hard water measurements. Results show that the final flotation recovery was directly proportional to the iodine value of sodium fatty acid. Sodium fatty acid with higher iodine value has higher solubility and dispersity in the solutions, and stronger foaming ability and resistance to hard water. After interacting with collophanite, sodium fatty acid with higher iodine value made the mineral more hydrophobic, thus contributing to better flotation performances.
EN
In order to selectively separate smithsonite and calcite using potassium lauryl phosphate as collector and reveal the depression mechanism, the approaches of micro-flotation and zeta potential measurements were adopted. The effects of sodium hexametaphosphate (SHMP), water glass (WG), carboxymethyl cellulose (CMC) and lignosulfonate calcium (LSC) as depressants on smithsonite and calcite have been studied through micro-flotation. The single mineral flotation tests show that LSC can depress calcite, but it has little effect on smithsonite flotation. Flotation separation of a mixture of smithsonite and calcite can be completed to obtain a zinc concentrate grade up to 33.85% Zn with a recovery of 70.06%. The zeta potential results illustrate that LSC has higher tendency to be adsorbed on the surface of calcite. However, there is little adsorption of LSC on smithsonite.
EN
Surface pretreatment using a hot alkaline solution was carried out to improve the effect of desulfurization and desilication on low-grade bauxite with high sulfur content. The results demonstrated that, after surface pretreatment, a maximum grade and recovery of 66.17% and 87.27%, respectively, were achieved, and the sulfur content and ratio of A/S were 0.19% and 7.09, respectively. The surface pretreatment mechanism was further analysed by XRD and SEM analyses. The improved results of desulfurization and desilication were attributed to the selective corrosion of aluminosilicate minerals in coarse particles, reducing the active silicon sites on the surface of coarse particles as well as enhancing the cation exchange between the collector and aluminosilicate minerals.
EN
Heterocoagulation can occur between fine siderite and hematite particles, which would result in the low efficiency of their separation during the flotation process. To date, there have been no mature methods to increase their separation efficiency. In this paper, citric acid was used as a regulator to enhance the slurry dispersion efficiency. Micro-flotation, scanning electron microscopy (SEM) analysis, settling tests, particle size measurements, zeta potential measurements and E-DLVO theoretical calculations were conducted in the investigations. A maximum recovery difference (53.98%) between siderite and hematite in their mixtures flotation was obtained. Settling tests confirmed that citric acid contributed to improving the dispersion degree of the slurry. SEM analysis indicated that citric acid could clean the surface of particles and weaken the coagulation between siderite and hematite, which were in line with the results of particle size measurements. The zeta potential measurements and Extended-Derjaguin-Landau-Verwey-Overbeek (E-DLVO) theoretical calculations indicated that the citric acid could adsorb on the siderite and hematite surfaces and decreased the surface charge, resulting in a visible increase of the repulsion energy between siderite and hematite particles. Therefore, citric acid can be applied to remove the easily-ground carbonate minerals first to improve the flotation performance of hematite in the separation process of carbonate-containing iron ores.
EN
The Chelopech epithermal arsenic bearing high-sulphidation, copper-gold deposit located in Bulgaria is often considered as the richest European gold deposit. Selected physicochemical parameters have been measured at key flotation streams inside the processing plant. Sampling campaign has followed with samples being submitted to chemical and mineral liberation analyses. A quantitative analysis has enabled to link copper flotation response to the type of copper bearing minerals and physiochemical parameters such as redox potential (Eh), dissolved oxygen (DO), EDTA extractable Cu and Fe. Data from the mineral liberation analysis (MLA) have highlighted an important process- relevant information explaining the variable floatability in different particle size ranges. A low chalcopyrite recovery can be linked to the non-sufficient amount of dissolved oxygen inside the copper selective flotation. Given the finely-disseminated copper bearing minerals, copper losses due to particle locking could be suggested as well.
EN
Nepheline syenite, which is a silica-poor crystalline rock, competes with feldspar in applications such as glass, ceramic filler, and pigment industries. While its appearance is medium coarse granular like granite, main differences between them are nepheline syenite is silica poor, and contains high alumina and alkali content. Turkey has considerable nepheline syenite deposits in Kırşehir Region, and they contain 1.3% Fe2O3 on average, thus cannot be used unless beneficiated by flotation or/and magnetic separation. In this paper, physical and physicochemical experiments were carried out to improve the quality of nepheline syenite ore. After determinations of chemical, mineralogical, and properties of the sample, three different technologies such as flotation, magnetic separation, and leaching were applied on the ore sample, separately and combined. The obtained results showed that the magnetic separation alone could not produce a nepheline syenite concentrate assaying 0.45% Fe2O3. It was not also possible to obtain a nepheline concentrate less than 0.25% Fe2O3 adapting optimum flotation conditions. The best results were found in combination of the high intensity wet magnetic separation and flotation between -212+63 μm particle size, and a final concentrate with 0.20% Fe2O3 and 0.01% TiO2 was obtained. The leaching experiments were conducted to further decrease Fe2O3 content. Finally, a saleable nepheline syenite concentrate for tile, sanitary ware, electrode, glass, and fiberglass industries was obtained with 6.63% K2O, 9.02% Na2O, 0.15% Fe2O3, and 0.01% TiO2 by the weight of 63.9% at the end of the experiments.
EN
The traditional separation process of pyrite and marmatite is carried out under highly alkaline conditions. Therefore, a large amount of lime is demanded and the zinc recovery cannot be guaranteed. However, under weakly alkaline conditions, copper-activated pyrite has good floatability, which is difficult to separate from marmatite. In this paper, ammonium chloride (NH4Cl) is used for depressing the flotation of copper-activated pyrite to achieve the separation of these two minerals under weakly alkaline environment. The flotation tests show that NH4Cl can significantly reduce the floatability of pyrite in weakly alkaline conditions. The results of adsorption tests and X-ray photoelectron spectroscopy (XPS) analyses indicate that NH4Cl can obviously change the composition of pyrite surface by increasing the content of iron/copper hydroxide and reducing the content of copper sulfides. Calculation of the solution composition demonstrates that the addition of NH4Cl results in the occurrence of Cu(NH3)n2+ and the pH buffering property. Based on these results, it can be concluded that the depression of NH4Cl on copper activated pyrite is mainly derived from two aspects: 1) the pH buffering property of the conjugated acid-base pair (NH4+/NH3) can impede the decline of OH- concentration, which results in more hydroxide adsorbed on pyrite; 2) NH3 (aq) competes with the pyrite surface to consume Cu2+through complexation, which causes a reduction in the amount of copper sulfides formed on the pyrite surface.
EN
Naturally, most of the cassiterite co-exists with sparingly soluble calcite, which makes it difficult to be fully utilized. Due to the adsorption of calcium ions dissolved from calcite, surface properties of cassiterite and its floatability can be influenced. Adsorption tests show calcium ions can adsorb on cassiterite surface. In the presence of Ca2+, the zeta potentials of cassiterite shift to more positive values and the isoelectric point of cassiterite increases from pH 4.4 to pH 4.9. XPS results show that after calcium ions treatment, a strong calcium spectral peak at 347.65 eV is detected on the cassiterite surface and the chemical circumstance of oxygen atoms is changed. The presence of Ca2+ can significantly depressed the flotation behavior of cassiterite with salicylhydroxamic acid (SHA) as collector. Its recovery is decreased by 26.03% compared to that without Ca2+ at SHA dosage of 8.0×10-4 mol/dm3. When increasing SHA concentration to 9.0×10-4 mol/dm3 and above, the depression effect is partly compensated and the recovery rises by about 20%. Contact angle values of cassiterite measured by the bubble method correspond well to the flotation performance. Hence the depression mechanism of Ca2+ in cassiterite flotation can be interpreted in two aspects: 1) the consumption of SHA due to complexation reactions in pulp; 2) a decrease of effective adsorption site for SHA on cassiterite because of the adsorption of Ca2+.
EN
The adsorption behaviors of an ether amine surfactant, N1-(3-((8-methyl-nonyl)oxy) propyl)propane-1,3-diamine, on collophane and quartz were studied. Batch adsorption experiments were conducted to characterize the thermodynamic behavior of the adsorption process and to calculate the maximum adsorption. Results demonstrated that the adsorption of the ether amine on quartz was greater than collophane. Adsorption mechanisms were studied by means of contact angle measurement, zeta potential measurement, FT-IR analysis, and X-ray photoelectron spectroscopy. The results showed that the adsorption of the ether amine surfactant on quartz surface was easier and more efficient than collophane. Micro-flotation tests testified that the collector can efficiently separate collophane from quartz at room temperature in neutral medium.
EN
One of the main challenges in the copper oxide processing industry is implementation of a flotation method to reduce operating costs. Sulphidising flotation is the most common used technique in which a sulphidisation agent is used to sulphidise the surface of the oxide minerals. In this research, the mentioned technique was used sequentially for the concentration of silicate-carbonate ore containing 3.1% Cu (malachite). The presence of 39% Cu in -38 μm size fraction (fine particles) of feed led to poor grades and recoveries in the initial tests. The addition of sodium sulfide and subsequent flotation at three sequential stages was identified as a successful operational initiative to solve this problem in the following tests. The dosages of 1500, 1567 and 100 g/Mg of sodium silicate, sodium sulfide and potassium amyl xanthate, respectively, the conditioning time of 5 min for sulphidisation and pH=9.72 were chosen as optimum operational conditions using central composite design (CCD) method of experiments design. The rougher concentrate with 9.28% grade and 81.15% recovery was obtained under these conditions. The grade of obtained concentrate was reached to 24% in the cleaner step. The total recovery of both steps was over 74%.
EN
The flotation wastewater treatment was considered in the paper. The main stages and parameters of flotation process were pointed out. The multistage flotation model considering all main stages of flotation process is presented. However, its main disadvantage is that for the definition of constant characterizing the bubble-particle aggregate formation, the constant value of superficial gas velocity was used, which is incorrect for horizontal flow flotation tank. The modified multistage flotation model with superficial gas velocity as the function of time was proposed. The experiments were carried out on a laboratory setup with a pneumohydraulic system of aeration in order to verify the proposed model. The comparison of experimental and theoretical results proved the importance of superficial gas velocity change consideration.
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