Special Issue "Selected Papers from “The 2nd International Conference of Young Scholars in Mineral Processing”"

A special issue of Minerals (ISSN 2075-163X). This special issue belongs to the section "Mineral Processing and Metallurgy".

Deadline for manuscript submissions: closed (30 November 2018)

Special Issue Editors

Guest Editor
Dr. Zhiyong Gao

School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China
Website | E-Mail
Interests: flotation of oxide minerals; mineral crystal chemistry; flotation reagent molecular design; mineral/reagent/water interfacial science; waste treatment in minerals processing
Guest Editor
Dr. Przemyslaw B. Kowalczuk

Department of Geoscience and Petroleum, Norwegian University of Science and Technology, 7491 Trondheim, Norway
Website | E-Mail
Interests: mineral processing; minerals engineering; flotation; physicochemistry of surfaces; colloids systems; hydrophobicity; minerals; surface properties; extractive metallurgy; leaching

Special Issue Information

Dear Colleagues,

The global mineral processing community faces significant challenges, ranging from technological to environmental and economic issues. The mineral processing community has confronted and solved such challenges over the centuries and has thereby delivered important contributions to the clean and efficient use of our mineral resources. This Special Issue aims to collect high quality research papers, short communications, and review articles that focus on a wide range of topics concerning mineral processing. The Special Issue will publish selected papers from the 2nd International Conference of Young Scholars in Mineral Processing, 21–23 August, 2017, in Changchun, China. The key objective of the 2nd International Conference of Young Scholars in Mineral Processing is to share the latest developments in mineral processing activities, developments, and research in China and beyond. We invite professionals from the mineral processing industry and practitioners, people from research institutions, as well as academic scholars and researchers to attend this conference. We are cordially inviting you to join us at the conference and also to submit your manuscript to this Special Issue.

Dr. Zhiyong Gao
Prof. Dr. Przemyslaw B. Kowalczuk
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Minerals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Technological mineralogy
  • Comminution & classification
  • Physical enrichment—gravity, magnetic and electrostatic separation
  • Surface chemistry, flotation fundamentals, flotation reagents, flotation technology
  • Processing of fines and slimes
  • Hydro- and bio-hydrometallurgy
  • Environmental problems and recycling of mineral-containing waste products
  • Process modeling
  • Pillarization, agglomeration and sintering
  • Dewatering

Published Papers (9 papers)

View options order results:
result details:
Displaying articles 1-9
Export citation of selected articles as:

Research

Open AccessArticle Hydrodynamic and Flotation Kinetic Analysis of a Large Scale Mechanical Agitated Flotation Cell with the Typical Impeller and the Arc Impeller
Minerals 2019, 9(2), 79; https://doi.org/10.3390/min9020079
Received: 29 November 2018 / Revised: 21 January 2019 / Accepted: 22 January 2019 / Published: 29 January 2019
PDF Full-text (9889 KB) | HTML Full-text | XML Full-text
Abstract
The processing of low grade mineral ores using large scale flotation cells is obviously more advantageous than smaller-scale processing. Large-scale flotation cells have become increasingly important for effective volume scale-up. In this study, the latest and largest flotation cell in China, with an [...] Read more.
The processing of low grade mineral ores using large scale flotation cells is obviously more advantageous than smaller-scale processing. Large-scale flotation cells have become increasingly important for effective volume scale-up. In this study, the latest and largest flotation cell in China, with an effective volume of 680 m3, is considered. Hydrodynamics and flotation kinetics analyses are conducted using computational fluid dynamics (CFD) simulation. It is demonstrated that the flotation cell with a typical impeller produces suitable hydrodynamics for mineral particles based on analysis of the flow pattern, gas dispersion and solid suspension. The performance of the large-scale flotation cell is studied using hydrodynamic performance parameters. The variation of the performance parameters, such as the power number (Np), the Froude number (Fr), the air flow number (Na), and so on, with the flotation cell volumes, followed trends similar to that of previous cells of a different size, which were proven to be effective for engineering applications. To decrease the detachment of mineral particles, a new type of impeller, for which the impeller plate is a hyperbolic curve, viz. an arc impeller, was developed. Compared with the typical impeller, the arc impeller expands and lifts the low circulating flow, thereby shortening the transportation distance of the mineral particles. The data indicates that kinetic eddy dissipation plays a key role in determining the collision kernel and collision probability profile. The newly designed arc impeller leads to a higher collision probability than the typical impeller, resulting in better flotation performance. This research should aid in the optimization of the structure of the 680 m3 flotation cell. Full article
Figures

Figure 1

Open AccessArticle Breakage Characterization of Grinding Media Based on Energy Consumption and Particle Size Distribution: Hexagons versus Cylpebs
Minerals 2018, 8(11), 527; https://doi.org/10.3390/min8110527
Received: 2 October 2018 / Revised: 9 November 2018 / Accepted: 10 November 2018 / Published: 13 November 2018
PDF Full-text (6194 KB) | HTML Full-text | XML Full-text
Abstract
The grinding performance of hexagon grinding media particles has been compared with that of cylpebs grinding media particles. A batch grinding test was conducted using equal masses of hexagons and cylpebs. The particle size distribution and energy consumption during grinding of the ground [...] Read more.
The grinding performance of hexagon grinding media particles has been compared with that of cylpebs grinding media particles. A batch grinding test was conducted using equal masses of hexagons and cylpebs. The particle size distribution and energy consumption during grinding of the ground product were analyzed, and the relationships among the specific surface area, bulk density, energy consumption, and t10 value are discussed. Under the same grinding conditions, the grinding capacity of hexagons was inferior to that of cylpebs. However, as the particle size of the feed became finer, the grinding effect of hexagons became more apparent. At the same time, the qualified particles content in the ground product was higher when using hexagons than when using cylpebs. The relationship between the specific surface area and energy consumption during grinding was consistent with the regular pattern of grinding fineness and energy consumption. In addition, the bulk density of minerals decreases with an increase in grinding energy. The same conclusion was obtained when −0.425 mm tungsten ore was used as a sample for validation. The flotation experiment result has carried out that hexagons as grinding media have a better flotation indicator than cylpebs in the same grinding fineness. It is demonstrated that although the grinding capacity of hexagons is inferior to that of cylpebs, less overgrinding occurs when using hexagons than when using cylpebs. For tungsten ore grinding, hexagons act as a finer grinding media than cylpebs. Full article
Figures

Graphical abstract

Open AccessArticle A New Concept on High-Calcium Flotation Wastewater Reuse
Minerals 2018, 8(11), 496; https://doi.org/10.3390/min8110496
Received: 7 October 2018 / Revised: 27 October 2018 / Accepted: 30 October 2018 / Published: 1 November 2018
PDF Full-text (1827 KB) | HTML Full-text | XML Full-text
Abstract
Calcium ions are a kind of unavoidable ions in water. It has the deleterious effect on molybdenite flotation. High-calcium flotation wastewater (HCFW) was reused for flotation circuits after the pretreatment removing Ca2+ in from HCFW. The high cost of wastewater treatment limits [...] Read more.
Calcium ions are a kind of unavoidable ions in water. It has the deleterious effect on molybdenite flotation. High-calcium flotation wastewater (HCFW) was reused for flotation circuits after the pretreatment removing Ca2+ in from HCFW. The high cost of wastewater treatment limits HCFW reuse. In this paper, an efficient, innovative, low-cost and environmental-friendly flotation wastewater reuse technology was introduced. XLM, as a composite collector for molybdenite, is a mixture of diesel oil (DO) and polycyclic aromatic hydrocarbons (PAHs). It could reduce the deleterious effects of Ca2+ on the flotation of molybdenite in HCFW. Therefore, this was used to replace the pretreatment removing Ca2+ in from high Ca2+ wastewater and saved the cost of wastewater treatment. When XLM consists of 4 wt % PAHs and 96 wt % DO, it has better adaptability than DO in the different Ca2+ concentration of flotation water. The contact angle measurements indicated that PAHs, as a synergistic component of a composite collector, could adsorb on the edges of molybdenite in the presence of Ca2+ by forming PAHs-Ca2+-MoO42− structure to increase the contact angle of fine molybdenite particle and reduce the deleterious effects of Ca2+ on the flotation of molybdenite. The industrial-scale test further that demonstrated XLM can improve the molybdenite roughing recovery and grade by 1.8% and 3.46% compared with DO as the collector in high Ca2+ flotation wastewater. It is feasible and effective to replace high-cost wastewater treatment for molybdenum plants. Full article
Figures

Figure 1

Open AccessArticle Degradation of Thiol Collectors Using Ozone at a Low Dosage: Kinetics, Mineralization, Ozone Utilization, and Changes of Biodegradability and Water Quality Parameters
Minerals 2018, 8(11), 477; https://doi.org/10.3390/min8110477
Received: 16 September 2018 / Accepted: 19 October 2018 / Published: 24 October 2018
PDF Full-text (3090 KB) | HTML Full-text | XML Full-text
Abstract
Ozonation at a high O3 dosage can achieve high efficiencies in removing flotation reagents but it has a low ozone-utilization rate. The ozonation of potentially toxic thiol collectors (potassium ethyl xanthate (EX), sodium diethyl dithiocarbamate (SN-9), O-isopropyl-N-ethyl thionocarbamate (Z-200) [...] Read more.
Ozonation at a high O3 dosage can achieve high efficiencies in removing flotation reagents but it has a low ozone-utilization rate. The ozonation of potentially toxic thiol collectors (potassium ethyl xanthate (EX), sodium diethyl dithiocarbamate (SN-9), O-isopropyl-N-ethyl thionocarbamate (Z-200) and dianilino dithiophoshoric acid (DDA)) was investigated in an ozone-bubbled reactor at a low O3 dosage of 1.125 mg/(min·L). The degradation kinetics, mineralization, ozone utilization, changes of biodegradability, and water quality parameters were studied, and the degradation behaviors of four collectors were compared. Thiol collectors could be effectively degraded with a removal ratio of >90% and a mineralization ratio of 10‒27%, at a low O3 dosage. The ozonation of thiol collectors followed the pseudo first-order kinetics, and rate constants had the order of kSN-9 > kEX > kZ-200 > kDDA. The Z-200 and DDA were the refractory flotation reagents treated in the ozonation process. After ozonation, the biodegradability of EX, SN-9, and DDA solutions was remarkably raised, but the biodegradability of Z-200 only increased from 0.088 to 0.15, indicating that the Z-200 and its intermediates were biologically persistent organics. After ozonation, the solution pH decreased from 10.0 to 8.0‒9.0, and both the conductivity and oxidation-reduction potential increased. The ozone utilization ratio in decomposing thiol collectors was above 98.41%, revealing almost complete usage of input O3. The results revealed that thiol collectors could be effectively degraded by O3, even at a low dosage, but their degradation behaviors were quite different, due to intrinsic molecular properties. Full article
Figures

Figure 1

Open AccessArticle Synchrotron Radiation XRD Investigation of the Fine Phase Transformation during Synthetic Chalcocite Acidic Ferric Sulfate Leaching
Minerals 2018, 8(10), 461; https://doi.org/10.3390/min8100461
Received: 7 August 2018 / Revised: 10 September 2018 / Accepted: 12 October 2018 / Published: 17 October 2018
PDF Full-text (1322 KB) | HTML Full-text | XML Full-text
Abstract
The fine phase transformation process of chalcocite (Cu2S) leaching in acidic ferric sulfate solution was studied by leaching experiments and synchrotron radiation X-ray diffraction (SRXRD) tests. The results showed that the dissolution process of chalcocite was divided into two stages. In [...] Read more.
The fine phase transformation process of chalcocite (Cu2S) leaching in acidic ferric sulfate solution was studied by leaching experiments and synchrotron radiation X-ray diffraction (SRXRD) tests. The results showed that the dissolution process of chalcocite was divided into two stages. In the first stage, Cu2S was firstly transformed to Cu5FeS4 and Cu2−xS, then the galvanic effect between Cu5FeS4 and Cu2−xS accelerated the dissolution process of Cu1.8S → Cu1.6S → CuS, and finally Cu5FeS4 was also transformed to CuS. While in the second stage, CuS was transformed to elemental sulfur, which formed the passivation layer and inhibited the leaching of chalcocite. Specifically, Cu5FeS4 was detected during the chalcocite leaching process by SRXRD for the first time. This research is helpful for revealing the detailed leaching process of chalcocite. Full article
Figures

Figure 1

Open AccessArticle Adsorption Structure and Mechanism of Styryl Phosphoric Acid at the Rutile–Water Interface
Minerals 2018, 8(8), 360; https://doi.org/10.3390/min8080360
Received: 21 July 2018 / Revised: 8 August 2018 / Accepted: 17 August 2018 / Published: 20 August 2018
PDF Full-text (2493 KB) | HTML Full-text | XML Full-text
Abstract
The microstructure and mechanism of styryl phosphoric acid (SPA) adsorbed at the rutile–water interface were investigated through zeta potential measurement, ultraviolet-visible spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The results of the zeta potential measurement illustrate that SPA [...] Read more.
The microstructure and mechanism of styryl phosphoric acid (SPA) adsorbed at the rutile–water interface were investigated through zeta potential measurement, ultraviolet-visible spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The results of the zeta potential measurement illustrate that SPA is mainly electrostatically adsorbed on the rutile surface, and the adsorption process and result can be well fitted by the Stern-Grahame equation. The adsorption is severely affected by pH due to different species of SPA occurring in different pH solutions. The compound of P–O–Ti, with a structure of bidentate binuclear or bidentate mononuclear complexes, is formed after SPA is adsorbed on the rutile surface. SPA can be adsorbed on the rutile surface through the coordination of self-polymerization and bidentate mononuclear, which greatly increases the hydrophobicity of the rutile surface. Based on the above analysis and discussion, we proposed the adsorption model of SPA at the rutile–water interface, which was conducive to the modification and synthesis of a highly efficient flotation collector of the primary rutile ore. Full article
Figures

Figure 1

Open AccessCommunication Reverse Flotation Separation of Fluorite from Calcite: A Novel Reagent Scheme
Minerals 2018, 8(8), 313; https://doi.org/10.3390/min8080313
Received: 17 June 2018 / Revised: 12 July 2018 / Accepted: 22 July 2018 / Published: 26 July 2018
Cited by 3 | PDF Full-text (905 KB) | HTML Full-text | XML Full-text
Abstract
Fluorite (CaF2), as an important strategic mineral source, is usually separated from calcite by the common froth flotation method, but this separation is still not selective enough. The development of a selective collector and/or depressant is the key to achieving high [...] Read more.
Fluorite (CaF2), as an important strategic mineral source, is usually separated from calcite by the common froth flotation method, but this separation is still not selective enough. The development of a selective collector and/or depressant is the key to achieving high selective separation. 1-Hydroxyethylidene-1,1-diphosphonic acid (HEDP or H4L) is widely used as an environmentally friendly water treatment reagent due to its low cost and excellent anti-scaling performance in an aqueous solution. In this study, a novel reagent scheme was developed using HEDP as a fluorite depressant and sodium oleate (NaOL) as a calcite collector for the first time. When 3 × 10−5 mol/L of HEDP and 6 × 10−5 mol/L of NaOL were used at pH 6, the optimal selective separation for single minerals and mixed binary minerals was obtained. Zeta potential measurements indicated that HEDP possessed a stronger adsorption on fluorite than calcite, while NaOL did the opposite. This novel reagent scheme is of low cost, uses a small dosage, and is friendly to the environment, which makes it a promising reagent scheme for fluorite flotation in industrial application. Full article
Figures

Graphical abstract

Open AccessArticle Adsorption Mechanism of Pb2+ Activator for the Flotation of Rutile
Minerals 2018, 8(7), 266; https://doi.org/10.3390/min8070266
Received: 23 May 2018 / Revised: 12 June 2018 / Accepted: 12 June 2018 / Published: 25 June 2018
Cited by 3 | PDF Full-text (2306 KB) | HTML Full-text | XML Full-text
Abstract
In general, the flotation of minerals containing titanium needs to be activated by metal ions due to a lack of activating sites on their surface. However, the activating process is indirectly inferred due to the lack of direct experimental observation. In this study, [...] Read more.
In general, the flotation of minerals containing titanium needs to be activated by metal ions due to a lack of activating sites on their surface. However, the activating process is indirectly inferred due to the lack of direct experimental observation. In this study, atomic force microscopy (AFM) was used to observe the activation process. The results revealed that the hydroxyl compounds of Pb2+ ions were adsorbed on the rutile surface in the form of multiple molecular associates, rather than through single molecule adsorption. Styryl phosphoric acid (SPA) could largely be adsorbed on the activated rutile surface with a single and double layer rather than on the un-activated rutile surface. The results of contact angle measurements also revealed that the hydrophobicity of the activated rutile surface was significantly greater than that of the un-activated rutile surface after SPA was adsorbed. This study will be helpful to understanding the activating process from the microscale. Full article
Figures

Figure 1

Open AccessArticle Different Flotation Performance of Ultrafine Scheelite under Two Hydrodynamic Cavitation Modes
Minerals 2018, 8(7), 264; https://doi.org/10.3390/min8070264
Received: 30 May 2018 / Revised: 14 June 2018 / Accepted: 16 June 2018 / Published: 23 June 2018
Cited by 1 | PDF Full-text (3094 KB) | HTML Full-text | XML Full-text
Abstract
In industrial practice, hydrodynamic cavitation (HC) is commonly triggered by jetting either reagent solution or pulp. Although both methods can enhance mineral flotation, are their roles the same? There are few research studies in the field, which severely limits our understanding on mineral [...] Read more.
In industrial practice, hydrodynamic cavitation (HC) is commonly triggered by jetting either reagent solution or pulp. Although both methods can enhance mineral flotation, are their roles the same? There are few research studies in the field, which severely limits our understanding on mineral flotation combined with HC. Therefore, in this study, the flotation of ultrafine scheelite with HC pretreatments of reagent solution and pulp (abbreviated to be HCPS and HCPP, respectively) was studied and compared through flotation tests, zeta potential analysis, microscope tests, and shear yield stress measurements. The results of flotation tests show that both HCPS and HCPP can enhance the final flotation performance, but in general, HCPP leads to greater improvements on the final flotation recovery. The presence of (hydrophobized) scheelite particles brings extra gas nuclei for the cavitation–flotation system, suggesting that more NBs may be produced in the case of HCPP compared with HCPS. These tiny bubbles remarkably reduce the size distribution of bubbles in the flotation system, thus increasing the particle–bubbles collision probability. Increase in particle aggregation may be another reason why flotation with HCPP results in a higher flotation recovery. The adherence of NBs on hydrophobized particles decreases the (absolute) surface charge of the solids, resulting in a smaller repulsive force among particles and more significant particle aggregation, which is confirmed by the microscope tests and shear yield stress measurements. Full article
Figures

Figure 1

Minerals EISSN 2075-163X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top