[Objective] To clarify the occurrence state and distribution pattern of associated cobalt resources in a high-sulfur bauxite from Guizhou and to guide the synergistic recovery of aluminum, sulfur, and cobalt resources, [Method] a systematic process mineralogy study was conducted using multiple analytical techniques, including multi-element chemical analysis, X-ray Diffraction (XRD), Automated Mineral Identification and Characterization System (AMICS), Electron Probe Microanalysis (EPMA), and optical microscopy. [Result] The main chemical components of the ore are Al2O3 (58.98%), TFe (7.96%), and SiO2 (5.98%), with a Co content of 0.005 9% (59 g/t). The primary mineral composition consists of diaspore (68.3%), pyrite (17.95%), and illite (8.83%), accompanied by minor amounts of quartz, anatase, dolomite, as well as trace minerals such as chalcopyrite and cobaltite. Cobalt occurs in two distinct forms: approximately 55.21% is incorporated in pyrite via isomorphism (average Co content 163.38 g/t), while about 44.79% exists as discrete cobaltite minerals. The intergrowth between pyrite and diaspore is complex, and the extremely fine-grained cobaltite (2～4 μm), often encapsulated in chalcopyrite, presents significant challenges to its liberation, thereby constituting a key limiting factor for cobalt recovery. [Conclusion] This study reveals for the first time the dual occurrence state of associated cobalt in high-sulfur bauxite and its constraining mechanism during the separation process, offering new insights for the effective enrichment and comprehensive recovery of cobalt resources from this type of ore.
[Objective] To develop a new process for extracting yellow phosphorus from phosphate rock powder by silicon thermal reduction and study its non-isothermal kinetic behavior, [Method] the reduction rate, residual phosphorus content, mineral phase structure and morphology were analyzed by ICP-OES, XRD and SEM-EDS. The activation energy (Eα) and mechanism function G(α) were calculated by Coats-Redfern method and statava-stestak method. [Result] Silicothermic reaction of phosphate ore started at about 1 000 ℃. The reduction process can be divided into two stages: the initial stage involved a small portion of Ca5(PO4)3F in the ore powder reacting with SiO2 to form the intermediate product Ca3(PO4)2, which subsequently reacted with silicon, whereas the latter stage comprised the remaining Ca5(PO4)3F reacting directly with silicon. A large number of pores were formed due to the escape of the produced phosphorous gas, and the phase was identified as calcium silicate. [Conclusion] The phosphorus extraction reaction by the silicon thermal method is controlled by the Avrami-Erofeev nucleation and growth model. Increasing the heating rate can reduce the apparent activation energy. The reduction process occurs significantly above 1 000 ℃ and undergoes two reaction stages.
[Objective] To address the limitation of existing chemical analysis methods in evaluating the enrichment of valuable elements such as iron, nickel, and cobalt in oxidized and silicate minerals of laterite nickel ores, [Method] certified reference materials of lateritic nickel ores as research subjects and simulated a hydrometallurgical process were used. The tests focused on key factors, including the type and ratio of selective extractants, extraction temperature, and roasting pretreatment. The optimal extraction parameters were identified as follows: a mixed extractant composed of 1.5 mol/L hydrochloric acid and 1 mol/L ammonium fluoride, with extraction performed at 135 ℃ using 25 mL of extractant and no pre-roasting. [Result] The impact of the extractant on the matrix and the instrumental parameters for ICP-OES determination were investigated. Method validation results showed that the precision (RSD, n=12) was≤5.79%. The detection limits for MgO, CaO, total iron (TFe), cobalt (Co), nickel (Ni), alumina (Al2O3), manganese (Mn), and chromium (Cr) were≤0.007 7%, For limonite-type samples, the leaching rates of nickel and cobalt reached 99% and 91.67%, respectively. For serpentine-type samples, the leaching rates were 97.6% and 91.3%. [Conclusion] These values are consistent with the recovery rates of nickel and cobalt in industrial hydrometallurgical processes，indicating that this method is highly effective for analyzing and testing available metal elements in oxidized and silicate minerals of laterite nickel ores.
[Objective] To explore the enhancing effect of sodium hexametaphosphate as an inhibitor on the flotation performance of low-rank coal slime and its mechanism of strengthening flotation, [Method] The flotation experiment was conducted with low-rank coal slime as the research object and sodium hexametaphosphate as the inhibitor, and the influence of sodium hexametaphosphate dosage on the flotation indexes was investigated. The enhanced flotation mechanism was analyzed based on the contact angle test, Zeta potential test and EDLVO theory. [Result] When the dosage of sodium hexametaphosphate was 800 g/t, the flotation indexes of low-rank slime were relatively good, the cleaned coal yield, ash content, combustible recovery and flotation perfection index were 53.95%, 30.25%, 87.33% and 46.92%, respectively, the cleaned coal yield increased by 6.24 percentage points, the ash content increased by 6.24 percentage points, the combustible recovery increased by 17.01 percentage points, and the flotation perfection index increased by 15.14 percentage points. The contact angle of low-rank coal slime increased by 18.1°, and the Zeta potential values were significantly increased. [Conclusion] Sodium hexametaphosphate mainly acted on the mineral surface through electrostatic force to enhance the electrostatic repulsion between particles, reducing the cover of kaolinite and quartz on low-rank coal slime and making the flotation system more dispersed, and so as to obtain better flotation effect.
[Objective] In order to reveal the structural properties of hemimorphite from the microscopic atomic level, first-principles calculations based on density functional theory were carried out. [Method] The band structure, density of states, Mulliken population, surface energy of different structures and differential charge density of hemimorphite were systematically analyzed. [Result] The high-energy electrons near the Fermi level in hemimorphite crystal are mainly contributed by the 2p orbit of O, with the best chemical reactivity, and easily become the mineral surface action site during flotation. There is substantial electron enrichment around O in the hemimorphite ore lattice and increased charge density. The electrons are missing from the outside of Zn and transferred to O, and the Zn-O bond exhibits the characteristics of an ionic bond. The population value of the Zn-O bond Mulliken is low, and the surface energy of the (1 1 0) surface broken along the Zn-O bond is minimum, and the polar ore (1 1 0) surface is the most likely cleavage surface exposed. [Conclusion] The research results systematically reveal the crystal and surface structure characteristics of hemimorphite, which can provide useful reference and guidance for the study of hemimorphite flotation behavior and the development of flotation reagents.
[Objective] Vein quartz is an important high-purity quartz material. To explore the influence of different technological processes on the content and occurrence form of fluid inclusions in gangue quartz, and to reveal the variation law of quartz particles during the purification process，[Method] mineralogy studies were conducted on DY and GS samples of vein quartz from different regions, and comparative experiments were conducted on the processes of magnetic separation-calcination quenching-flotation-hot pressing acid leaching and magnetic separation-calcination quenching-hot pressing acid leaching for each sample. [Result] After magnetic separation-calcination quenching-flotation-hot pressing acid leaching and magnetic separation-calcination quenching-hot pressing acid leaching, the SiO2 content of DY sample increased from 99.827% to 99.946% and 99.943%, respectively, and the SiO2 content of GS sample increased from 98.960% to 99.958% and 99.957%. Hence, low chemical composition of the raw ore did not necessarily result in poor purification efficiency, and flotation had almost no effect on the chemical composition of each sample. [Conclusion] According to the statistics analysis of the inclusions in the flotation concentrates, flotation had the significant impact on the removal of fluid inclusions in quartz, and it was beneficial for the removal of many quartz particles with fluid inclusions.
[Objective] Aiming at the problem that fine-grained magnesia-silicate gangue minerals are prone to be mechanically entrained during flotation, which affects the grade of concentrate, this paper provides a reference for the theoretical and technological development of reducing the magnesium content in concentrate from the perspective of the surface properties of bubbles. [Method] Taking flotation foam as the research object, this paper summarizes the pathways and influencing factors of fine magnesia-silicate gangue minerals carried by foam during the flotation process of metal sulfide ores, analyzes the bubble size, surface tension, surface ζ potential and the electrostatic interaction with fine gangue, as well as the current methods for solving gangue entraination. [Result] The influence of the properties of flotation foam on the entrainment of gangue minerals was systematically introduced mainly from the perspective of the surface properties of bubbles, such as bubble size, surface force and surface electrical properties. [Conclusion] The current detection methods are still difficult to clearly express the force and charged state on the bubble surface. In the future, in-depth research is needed on the influence of multi-component and complex surfactants on the changes in bubble surface properties.
[Objective] Siderite is a typical refractory iron ore. Strengthening the research on the beneficiation of siderite can effectively alleviate the shortage of iron ore supply in China and ensure the sustainable development of steel enterprises. [Method] A certain rhombic and red mixed iron ore in Gansu Province contains 38.16% iron. In view of the characteristics of this ore, an experimental study was conducted using the process flow of magnetic roasting - weak magnetic separation. [Result] Magnetic roasting was carried out at the conditions of no addition of reducing agent, roasting temperature of 700 ℃ and roasting time of 40 min. After grinding the roasted product to a particle size of -0.045 mm 85%, it was subjected to two stages of weak magnetic separation to obtain iron concentrate with an iron grade of 65.26% and an iron recovery rate of 86.46%. And the content of impurities such as SiO2, Al2O3, S and P is low. [Conclusion] Magnetic roasting - weak magnetic separation is an effective process for the separation of siderite. The research provides a technical basis for the efficient utilization of siderite resources.
[Objective] The flotation purification of phosphogypsum is an important way for its resource utilization. To solve the problems of traditional flotation collectors such as sensitivity to slime, poor solubility, difficulty in degradation and instability, [Method] based on the phosphogypsum of a mining company in Yichang, Hubei Province, a self-made quaternary ammonium salt collector (LLSG-1) was developed. The experiments of reverse flotation purification, impurity removal and whitening of phosphogypsum were carried out. [Result] Using the raw ore with a purity of 88.14%, a whiteness of 33.88%, and a SiO2 content of 6.26%, at the condition of pH value ranging from 2.3 to 2.5, with LSG-1 as the collector and MIBC as the foaming agent, after three-stage flotation, a purity of 93.61% and a whiteness of 65.19% were obtained. Phosphogypsum concentrate with a SiO2 content of 1.87% was also obtained. [Conclusion] The quality of the concentrate meets the first-class standard for building gypsum as stipulated in GB/T 23456-2018 "Phosphogypsum". The research provides technical support for the efficient recovery of phosphogypsum resources.
[Objective]To explore the effect of separating iron elements in a gold mine in Sichuan by using polyetheramine and mixed collector flotation method.[Method]The composition of the ore was determined through phase and elemental analysis.Flotation experiments using a single polyetheramine D-2000 collector,a mixed polyetheramine-sodium oleate collector,and sulfuric acid dissolution experiments were conducted to investigate the total iron content and mass proportion of the floating products under different conditions.[Result]In the flotation experiment with a single collector,polyetheramine D-2000 was used as the collector.When the dosage of polyetheramine D-2000 was 2 mL(0.1 mol/L)and the pH value was 1,the total iron content of the floating product reached 47.5％,indicating that polyetheramine can achieve iron separation in gold mines.The flotation experiment of the polyetheramine-sodium oleate mixed collector shows that the addition of sodium oleate further improves the separation rate of the floating products and the sinking products.When pH=5,the proportion of the floating mass after flotation with a mixed collector increased by 30.2％compared with that after flotation with a single collector.The total iron content increased by 0.7％.It is indicated that the flotation effect of the mixed collector is superior to that of using polyetheramine alone.The sulfuric acid dissolution experiment shows that when the solid-liquid ratio is I∶10,the total iron content reaches a maximum of 30.93％.[Conclusion]The use of polyetheramine D-2000 as a collector can effectively separate iron elements from gold ores.Adding sodium oleate to form a mixed collector can further increase the mass proportion and total iron content of the floating products,and the flotation effect is superior to that of a single collector.
[Objective] In order to increase the flotation efficiency of gold mines, mining plants often add flotation reagents to the dereagent system, which results in a large amount of flotation reagents in the flotation gold concentrate, especially collectors and frothers. The adsorption state of collectors on mineral surface is relatively complex, with most of them mainly relying on chemical adsorption and difficult to naturally desorb. The synergistic effect of frothers and collectors makes the existence forms of reagents on mineral surface more complex and difficult to remove. Flotation gold concentrates often contain a large amount of flotation reagents. These reagents can have adverse effects on subsequent microbial preoxidation operations, fine grinding cyanidation operations and carbon adsorption operations. Therefore, it is necessary to undergo dereagent treatment of gold concentrate before microbial preoxidation or cyanidation. [Method] According to the principle of dereagent process, the dereagent process can be divided into the physical dereagent process, the chemical dereagent process, and the physical-chemical combined dereagent process. The physical dereagent process is green and has high universality, but it is inefficient and generates a lot of wastewater. The chemical dereagent process is complete and efficient, but it is pollution, high cost, and requires subsequent wastewater treatment. The physical-chemical combined dereagent process can achieve low-pollution and efficient dereagent by combining the advantages of two dereagent processes, while it will increase the process flow and equipment cost. [Result&Conclusion] Green and efficient dereagent processes are an important research direction, and improving the cyclic treatment and utilization of dereagent wastewater, while achieving short process and automation of dereagent equipment, are also a trend in the development of dereagent processes.
[Objective] The drilling of ultra-deep wells over 10,000 meters in the oil and gas industry has gradually become a reality, and there is a great demand for weighting agents in ultra-high density drilling fluids. To recover the solid phase of weighting agents contained in the returned waste drilling fluid, save costs while treating solid waste and protecting the environment, [Method] the ‘clean gel breaking + high-speed water washing’ process is utilized to enrich barite in the waste drilling fluid. Subsequently, the reverse flotation method is adopted to remove the useless solid phase. The corresponding recovery process is designed and optimized. [Results] At the conditions of a solid-liquid ratio of 1∶2, a rotational speed of 1,000 r/min, and a single addition of the cleaning gel breaker YJ-1 at 5‰, high-quality barite with a density of 4.127 g/cm3 can be obtained. By adopting the "one coarse, two fine and one sweep" flotation process, with the collector sodium dodecyl sulfate dosage of 700 g/t and the food gel-type inhibitor gellan gum dosage of 700 g/t, a barite mixed concentrate with a comprehensive recovery rate of 81.86%, a comprehensive grade of ≥ 92%, and a mixed concentrate density of ≥4.2 g/cm3 can be obtained. [Conclusion] The method is characterized by clean pharmaceuticals, simple process and excellent quality of recovered barite, which may provide some ideas for the reuse of barite from waste drilling fluids in the oil and gas field wells.
[Objective] To systematically evaluate the release characteristics of heavy metal elements in water-quenched slag, arsenic-alkali slag and lead removal slag produced by antimony pyrometallurgical smelting at different environmental conditions, and to provide a scientific basis for their environmental pollution prevention and harmless disposal, [Methods] the chemical elements and phase composition, leaching toxicity and environmental release characteristics were studied. [Result] Water-quenched slag contains a small amount of antimony (1.47%), while the concentration of the main heavy metals in the water-quenched slag does not exceed the national standard limit, but the leaching concentration of Sb element is higher. The main elements of arsenic-alkali residue include As (15.68%), Sb (16.78%), and arsenic-alkali residue toxicity test shows that As, Se element leaching toxicity exceeds the standard limit, and Sb element leaching concentration reaches 255.87 mg/L, far exceeded the "Emission standards is of pollutants for stannum, antimony and mercury Industries GB 33770-2014" in the Sb element emission limits (1 mg/L). In addition to the lead slag in the Pb, Cd leaching concentration of the elements exceeded the standard, Sb leaching concentration of 354 mg/L, with a very high degree of environmental hazards. [Conclusion] Among the three typical solid wastes, water-quenched slag has relatively low environmental risks. However, the leaching concentrations of As, Se, and Sb in arsenic-alkali slag, as well as Pb, Cd, and Sb in lead removal slag, all seriously exceed the standards, posing extremely high environmental hazards and urgently requiring harmless disposal and resource utilization.
[Objective] Titanium is a kind of metal with important strategic significance, and rutile is the main and most valuable titanium-bearing mineral. However, rutile has poor natural floatability, and is usually associated with many metals and doped with many gangue minerals, which makes the separation process complicated. Exploring the mechanism of flotation collector and developing high efficiency collectors have become the focus of rutile flotation research. [Method] This article introduces the principle of rutile flotation and the types of collectors, summarizes the adsorption mechanism of rutile flotation collector on mineral surface and the synergistic effect of composite collectors, [Result&Conclusion] summarizes and compares the advantages and disadvantages of different flotation agents, and analyzes the development direction of rutile collector theory research.
[Objective] Strong acid leaching is the main measure taken in spodumene smelting, which has an important impact on the physicochemical properties of its smelting slags (lithium slags). To clarify the impact of acid leaching process on the cementitious activity of lithium slags and achieve large-scale consumption of lithium slags in the field of building materials, [Method] physicochemical properties of the two types of lithium slags and their effects on the mechanical properties and working properties of cement mortar were studied, and the influence mechanism of acid leaching process on the gelling activity of lithium slag was analyzed by combining XRD, TG-DTG, FT-ID and MIP test methods. [Result] The most suitable lithium slag content in the cementitious system is 20%, and the mechanical properties of the NLS group mortar are generally higher than those of SLS. At 7～14 d, NLS quickly participated in the volcanic ash reaction, inducing hydration products such as calcium aluminosilicate (C-A-S-H) gel and calcium silicate hydrate (C-S-H), thereby densifying the pore structure and promoting the development of mechanical properties of the sample. [Conclusion] The amorphous phase material with relatively low content in SLS also participated in the volcanic ash reaction in the later stage, but due to the high content of SO3, more AFt and other products were formed, which had a certain negative impact on the sample.
[Objective] Vanadium and chromium resources play a critical role in various industries such as energy, chemicals, aerospace, and alloys. Securing a reliable supply of these resources is extremely crucial for the advancement of the national economy, as well as for national defense and military strength. As the availability of high-quality mineral resources decrease and the necessity for environmentally- friendly resource development increases, the extraction and separation of vanadium and chromium from complex vanadium and chromium resources has become an increasingly pressing issue. [Method] Currently, there has been a significant research conducted on the separation technology for complex vanadium and chromium resources. [Result&Conclusion] This article provides a systematic overview of vanadium and chromium mineral resources and secondary resources, as well as vanadium and chromium extraction technology in complex vanadium and chromium resources, and summarizes the principles, methods, advantages and disadvantages of vanadium and chromium separation technology in solution. The current status of the development of several separation techniques such as chemical precipitation, crystallization, extraction, electrochemical methods and ion precipitation flotation and their application prospects are analyzed. Addtionally, suggestions were put forward for the future development direction of vanadium-chromium extraction and separation processes.
[Objective] To address the issues of complex properties, uneven oxidation rates, and the difficulty in comprehensive recovery of coexisting and associated valuable elements in the Jiangla Angzong copper-gold polymetallic deposit, [Method] a comprehensive study on the raw ore properties from the Jiangla'angzong mining area was conducted, including multi-element chemical analysis, copper chemical phase analysis, ore structure and texture, identification and quantification of valuable and gangue minerals, and contents of associated valuable and deleterious elements. Based on these findings, laboratory beneficiation process testing for this copper ore was carried out. [Result] At the condition that the grinding fineness of -0.074 mm 85.00%, a beneficiation flowsheet comprising one roughing, one scavenging, and two cleaning flotation for sulfide copper recovery, followed by acid leaching of the tailings to recover oxide copper, yielded a sulfide copper concentrate. This concentrate had a yield of 2.79%, grading 16.74% Cu, 3.57 g/t Au, and 131.00 g/t Ag, with metal recoveries of 47.32% for Cu, 49.86% for Au, and 52.28% for Ag. The leaching rate of copper was 35.40%. the combination of the flotation recovery rate and the leaching rate of copper was 82.72%. [Conclusion] Due to the mine's location in the high-altitude hinterland, characterized by low ambient temperatures and low atmospheric oxygen levels, on-site implementation should consider moderate oxygenation and slurry heating to ensure effective flotation performance.
[Objective] In order to improve the utilization efficiency of tailings and reduce the environmental problems caused by tailings storage, this article focuses on molybdenum tailings as the main research object, and couples molybdenum tailings with slag powder to prepare cement-based materials. [Method] Based on the study of the basic physicochemical properties of molybdenum tailings, the effects of different proportions of molybdenum tailings and slag powder on the mechanical properties of colloidal sand test block were investigated. The hydration products and microstructure of the hardened slurry were analyzed by XRD, TG, IR and SEM. [Result] Molybdenum tailings are mainly composed of silicon and aluminum, and the mineral components are mainly plagioclase, pyroxene and hornblende. The 28 d activity index of molybdenum tailings is 67%. When the mass ratio of slag powder and tailings is 2∶1, the 28 d compressive strength of the mortar test block is 55.2 MPa, and the contribution rate of activity is 45.3%. [Conclusion] The hydration products of hardened paste are mainly C-(A)-S-H gel and Ca(OH)2. With the increase of age, the hydration products increase, the structure of hardened paste gradually becomes dense, and the strength increases.
[Objective]In order to conduct comprehensive utilization research on the weathering crust type vanadium-titanium magnetite in the Panxi Area,and ensure the sustainable development of vanadium-titanium iron resources in China,[Method]this study is based on the analysis methods of process mineralogy,investigating the chemical composition and mineral composition of the weathered crust vanadium-titanium magnetite ore in Panxi Region.In addition,a series of iron separation process experiments were conducted on the pyroxenite-type and gabbro-type weathered run-of-mine ores,including'dry throwing preselection-staged-grinding and staged-dressing-fine-grinding and deep-processing'.[Result&Conclusion]Ultimately,high-quality vanadium-titanium iron concentrates were obtained,with a TFe grade of 58.35％and a TFe recovery of 72.27％for the pyroxenite-type iron concentrate Ⅱ,as well as a TFe grade of 58.13％and a TFe recovery of 33.70％for the gabbro-type iron concentrate Ⅱ,achieving comprehensive recovery of high-quality vanadium-titanium iron concentrates.
[Objective] In view of the distribution differences of gold and silver in different concentrates of a certain mixed ore in Shandong, the aim is to study and achieve the effective separation and recovery of gold and silver in different concentrates. [Method] The trend and the distribution of Au and Ag in each separation concentrate was found. The Au and Ag recovery tests were carried out for sulfur concentrate, magnet concentrate and high magnetic products, and the reasonable recovery process was put forward to. [Result]The Au content of sulfur concentrate and magnet concentrate is 2.03 g/t and 1.11 g/t, respectively, and the Ag content of sulfur concentrate is 30.54 g/t, which has a high recovery value. The strong magnetic product contains Au 0.46 g/t, which needs to be further enriched before recovery. Ag in magnetite concentrate and strong magnetic product is low, and the recovery value is not great. The technological processes of "roasting-cyanide leaching", "direct cyanide leaching" and "flotation enrichment" were determined respectively for sulfur concentrate, magnet concentrate and strong magnetic product. The recovery of Au and Ag was 20.37% and 15.25% respectively by the roasting cyanide leaching process. The recovery of Au and Ag was 10.63% and 1.86% respectively by the direct cyanide leaching process. [Conclusion] The flotation concentrate with recovery of Au and Ag of 3.31% and 2.00%, respectively was obtained by the flotation process. The total recovery of Au and Ag was 87.94% and 74.09%, respectively.
