The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with t...The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with the advantage of being environmental-friendly.As one of the organic acids produced by biological metabolism,citric acid was used to leach REEs and explore the performance and process.The results demonstrate that citric acid exhibits higher leaching efficiency(96.00%)for REEs at a relatively low concentration of 0.01 mol/L compared with(NH_(4))_(2)SO_(4)(84.29%,0.1 mol/L)and MgSO_(4)(83.99%,0.1 mol/L).Citric acid shows a preference for leaching heavy rare earth elements,with 99%leaching efficiency in IAREO,which shows higher capacity than(NH_(4))_(2)SO_(4)and MgSO_(4)(as inorganic leaching agents).Kinetic analysis indicates that the leaching process of REEs with citric acid is controlled by both the internal diffusion kinetics and chemical reaction kinetics,which is different from inorganic leaching agents.Visual Minteq calculations confirm that RE-Citrate is the main constituent of the extract solution in the leaching process of the IAREO,thereby enhancing the leaching efficiency of REEs from the IAREO.It suggests that citric acid may be used as a promising organic leaching agent for the environmentalfriendly extraction of REEs from IAREO.展开更多
Weathered crust elution-deposited rare earth ores(WREOs)are rich in medium and heavy rare earth.In order to improve the in-situ leaching process,which is prone to landslides and poor permeability,cationic hydroxyethyl...Weathered crust elution-deposited rare earth ores(WREOs)are rich in medium and heavy rare earth.In order to improve the in-situ leaching process,which is prone to landslides and poor permeability,cationic hydroxyethyl cellulose(PQ-10)was used as a novel green swelling inhibitor and percolation promoter and was mixed with conventional leaching agent ammonium sulfate((NH_(4))_(2)SO_(4))to form a composite leaching agent to study the performance and mechanism of swelling inhibition and percolation promotion.Adding PQ-10 can inhibit the hydration swelling of WREOs,promote the percolation effect of the leaching agent,improve the rare earth(RE)leaching efficiency,and reduce the im purity aluminum(Al)leaching efficiency.Compared with the conventional leaching agent 2 wt%(NH_(4))_(2)SO_(4),the percolation time is reduced by 50%by using the composite leaching agent(0.02 wt%PQ-10+2 wt%(NH_(4))_(2)SO_(4)).PQ-10 has positively charged quaternary ammonium groups and hydrophilic group hydroxyl groups,which makes it easy to adsorb on WREOs multiple sites through electrostatic interaction and hydrogen bonding,weakening the electrostatic repulsion between mineral particles,reducing the WREOs interlayer spacing,compressing the double electric layer thickness at the solid-liquid interface,weakening the mineral hydration swelling and increasing the percolation rate.The long carbon chains of the polymer entangle and link the fine mineral particles to agglomerate them,increasing their particle size and reduc ing their hydration dispersion,and preventing blockage of the pe rcolation pores caused by migration of the fine particles through the ore body with the solution.PQ-10 molecules also insert the mine ral interlayer and expulsion of the internal water,further inhibiting the swelling of WREOs.Adding PQ-10 reduces the surface tension of(NH_(4))_(2)SO_(4)solution,improving the spreading and spreading ability of the solution,reducing the adhesion work between molecules in the solid-liquid phase and the adhesion work reduction factor.It proves that PQ-10 promotes the percolation effect of the leaching process of WREOs.In addition,PQ-10 expands the leaching pore size and seepage channels,further improving the percolation rate.展开更多
Stainless steel,known for its exceptional properties and diverse applications,conventionally requires a multistage process that generates considerable CO_(2) emissions by using fossil-based carbon reductants.This stud...Stainless steel,known for its exceptional properties and diverse applications,conventionally requires a multistage process that generates considerable CO_(2) emissions by using fossil-based carbon reductants.This study investigated hydrogen plasma smelting reduction as a novel,sustainable,and efficient method for producing stainless steel directly from lateritic nickel and chromite ores.The research aimed to examine the effect of ore proportion on AISI 300 series stainless steel production and assess the reduction process over time through thermochemical calculations and experimental studies.Results showed that increasing the proportion of chromite ore in the feed raises Cr content and reduces Ni content in metals while increasing Cr_(2)O_(3) and Al_(2)O_(3) content in oxides.A briquette comprising 30wt%chromite ore and 70wt%calcined nickel ore yields better results for AISI 300 stainless steel,with Fe,Cr,Ni,and Si content of 62.95wt%,19.37wt%,11.83wt%,and 0.72wt%,respectively,after 180 s of hydrogen plasma exposure.Nearly all NiO compounds are converted into Ni after 60 s of smelting reduction,whereas FeO compounds are almost fully converted into Fe after 120 s of smelting reduction.AISI 300 series stainless steel is successfully produced after 120 s of reduction,achieving Fe,Cr,Ni,and Si content of 64.36wt%,21.92wt%,10.08wt%,and 0.61wt%,respectively.Process optimization remains promising because the Cr_(2)O_(3) content in the slag is still relatively high at 15.52wt%.This ultrafast and direct production method holds considerable potential to transform stainless steel production by reducing environmental impact and enhancing process efficiency.Specifically,the method eliminates the use of an argon oxygen decarburization converter and vacuum oxygen decarburization in stainless steelmaking.展开更多
The semi-molten smelting process of a mixture of saprolitic and limonitic laterite ores was systematically investigated and the effect of slag basicity was deeply analyzed.The results indicate that the slag system can...The semi-molten smelting process of a mixture of saprolitic and limonitic laterite ores was systematically investigated and the effect of slag basicity was deeply analyzed.The results indicate that the slag system can be located in the liquidus region of low melting-point diopside(CaMgSi_(2)O_(6))when slag basicity is kept at 0.3 and limonitic laterite mass fraction is not less than 10%.When the reduction temperature,C/O mass ratio,limonitic laterite mass fraction and slag basicity are kept at the optimum values of 1300℃,0.86,20%and 0.3,respectively,ferronickel products with grades 6.42%Ni and 86.99%Fe are prepared.The recovery rates of Ni and Fe reach 88.60%and 72.25%,respectively.展开更多
Detection of ore waste is crucial for achieving automation in mineral metallurgy production.However,deep learning-based target detection algorithms still face several challenges in iron waste screening,including poor ...Detection of ore waste is crucial for achieving automation in mineral metallurgy production.However,deep learning-based target detection algorithms still face several challenges in iron waste screening,including poor lighting conditions in underground mining environments,dust disturbances,platform vibrations during operation,and limited resources for large-scale computing equipment.These factors contribute to extended computation times and unsatisfactory detection accuracy.To address these challenges,this paper proposes an ore waste detection algorithm based on an improved version of YOLOv5.To enhance feature extraction capabilities,the RepLKNet module is incorporated into the YOLOv5 backbone and neck networks.This module enhances the deformation information of feature extraction with the maximum effective Receptive Field to increase the model's accuracy.The Normalizationbased Attention Module(NAM)was introduced to enhance the attention mechanism by focusing on the most relevant features.This improves accuracy in detecting objects against noisy or unclear backgrounds,thereby further enhancing detection performance while reducing model parameters.Additionally,the loss function is optimized to constrain angular deviation using the SIOU loss function,which prevents the training frame from drifting during training and enhances convergence speed.To validate the performance of the proposed method,we tested it using a self-constructed dataset comprising 1,328 images obtained from the crushing station at Jinchuan Group's No.2 mine.The results indicate that,compared to YOLOv5s on the self-constructed dataset,the proposed algorithm achieves an 18.3%improvement in mAP(0.5),a 54%reduction in FLOPs,and a 52.53%decrease in model parameters.The effectiveness and superiority of the proposed algorithm are demonstrated through case studies and comparative analyses.展开更多
As a refractory iron ore,the clean and efficient beneficiation of limonite is crucial for ensuring a sustainable long-term supply of iron metal.In this study,the microwave fluidization magnetization roasting of limoni...As a refractory iron ore,the clean and efficient beneficiation of limonite is crucial for ensuring a sustainable long-term supply of iron metal.In this study,the microwave fluidization magnetization roasting of limonite was explored.The micromorphology,microstructure,and mineral phase transformation of the roasted products were analyzed using a scanning electron microscope,an automatic surface area and porosity analyzer,an X-ray diffractometer,and a vibrating sample magnetometer.Kinetic analysis was also conducted to identify the factors limiting the roasting reaction rate.Microwave fluidization roasting significantly increased the specific surface area of limonite,increased the opportunity of contact between CO and limonite,and accelerated the transformation from FeO(OH)toα-Fe_(2)O_(3)and then to Fe_(3)O_(4).In addition,the water in the limonite ore and the newly formed magnetite exhibited a strong microwave absorption capacity,which has a certain activation effect on the reduction roasting of limonite.The saturation magnetization and maximum specific magnetization coefficient increased to 23.08 A·m^(2)·kg^(-1)and 2.50×10^(-4)m^(3)·kg^(-1),respectively.The subsequent magnetic separation of the reconstructed limonite yielded an iron concentrate with an Fe grade of 59.26wt%and a recovery of 90.07wt%.Kinetic analysis revealed that the reaction mechanism function model was consistent with the diffusion model(G(α)=α^(2)),with the mechanism function described as k=0.08208exp[-20.3441/(R_(g)T)].Therefore,microwave fluidization roasting shows significant potential in the beneficiation of limonite,offering a promising approach for the exploitation of refractory iron ores.展开更多
Weathered crust elution-deposited rare earth ores(WREOs)in China are the main source of medium and heavy rare earths in the world.In order to improve the seepage and the mass transfer of traditional ammonium salt leac...Weathered crust elution-deposited rare earth ores(WREOs)in China are the main source of medium and heavy rare earths in the world.In order to improve the seepage and the mass transfer of traditional ammonium salt leaching process of WREOs,surfactants were added in the ammonium sulfate leaching solution and the ammonium chloride leaching solution.The leaching kinetics,the mass transfer process,and the adhesion work reduction factor calculated from the interfacial properties were studied to reveal the strengthening mechanism of surfactant.In the presence of the tested five surfactants,cetyl trimethyl ammonium bromide(CTAB),dodecyl trimethyl ammonium bromide(DTAB),sodium dodecyl sulfate(SDS),sodium oleate and oleic acid,the permeability of WREOs is improved,the rare earth(RE)leaching efficiency increase and the impurity aluminum(Al)leaching efficiency decrease,indicating its promotional effect on the leaching process of WREOs.Furthermore,CTAB shows a better leaching enhancement,and the optimal addition dosage is 0.4 g/L for the two ammonium salt leaching agent systems.The kinetics analysis shows the internal diffusion controls model of RE and Al leaching process,and the leaching kinetics equations of RE and Al related to CTAB concentration were obtained for the two ammonium salt leaching systems.According to the chromatographic plate theory,the mass transfer efficiency of RE increases with the CTAB concentration increasing until 0.4 g/L,which confirms that the optimal CTAB addition is 0.4 g/L.Smaller adhesion work and adhesion work reduction factor indicate more favorable permeation as well as the leaching process.展开更多
Super-high bed sintering process is an important development direction of iron ore sintering for its lower emission and higher yield.However,there is a lack of deep understanding of the uneven quality of super-high be...Super-high bed sintering process is an important development direction of iron ore sintering for its lower emission and higher yield.However,there is a lack of deep understanding of the uneven quality of super-high bed sintering products,and the deterioration of reduction disintegration performance,the thickening of hearth layer and the reduction in energy-saving effect are perplexing enterprises and researchers.To ascertain the problems of super-high bed sintering,ten sintering machines with the areas of 265,280,360,550 and 660 m^(2)and bed depth above 900 mm were sampled and analyzed.The results showed that problems were mainly shown in the unevenness of chemical composition,macrostructure,mechanical strength and metallurgical performance.The chemical composition exhibits severe segregation in both horizontal and vertical directions,with basicity segregation reaching as high as 0.81.The uneven macrostructure of sinter is reflected in a 10%difference in porosity and mechanical strength increase in 16%–19%along the vertical direction.The reducibility and reduction disintegration performance gradually deteriorate along the bed depth,with a difference of 10.5%in reducibility and 7.3%in RDI−0.5 mm(reduction disintegration index of sinter with size smaller than 0.5 mm).展开更多
The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous research.To inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material ...The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous research.To inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were executed.The results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,respectively.From the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 mm.Fluxes and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm ones.The heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel distribution.The inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid phase.The inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing results.Homogeneous mineralizing condition is the key for homogeneous super-high bed sintering.展开更多
Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were studied.Received data on the composition of...Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were studied.Received data on the composition of REE exhibit both the distinct negative(Ce/Ce*_(PAAS)<1)and positive(Ce/Ce*_(PAAS)>1)cerium anomalies and the positive Eu-anomaly(Eu/Eu*_(PAAS)>1).Negative Eu-anomalies are not observed.The contents of Mn,Fe,REE,and Ce-anomalies show a positive correlation with each other.Ce-anomalies and the amount of manganese and REE in relation to the carbon isotope composition(δ^(13)C)show a negative relationship and indicate that oxidized carbon of organic matter played an important role in the concentration of manganese and REE in manganese ores.The chemical and isotope composition of examined rocks indicates on secondary formation of Mnores.Two major phases and sources are distinguished in the ore-forming process characterized by diff erent chemical(REE and ore elements)and isotope composition:(i)highgrade manganese ores(with high contents of REE and light carbon isotope composition)and(ii)low-grade manganese ores(with low contents of REE and heavy carbon isotope composition).展开更多
Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanid...Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward.展开更多
The method of infrared thermography to predict the temperature of the sulfide ores has a large error. To solve this problem, the temperature of the sulfide ores is measured by thermal infrared imager and recording the...The method of infrared thermography to predict the temperature of the sulfide ores has a large error. To solve this problem, the temperature of the sulfide ores is measured by thermal infrared imager and recording thermometric instrument contrastively. The main factors, including emissivity, distance, angle and dust concentration that affect the temperature measurement precision, are analyzed. The regression equations about the individual factors and comprehensive factors are obtained by analyzing test data. The application of the regression equations improves the precision of the thermal infrared imager. The geometric information lost in traditional infrared thermometry is determined by visualization grid method and interpolation method, the relationship between the infrared imager and geometry information is established. The geometry location can be measured exactly.展开更多
In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials ...In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials and their self-heating characteristics were measured in laboratory. Furthermore, the measured temperature was studied by integrating wavelet transform, nonlinear characteristic parameters extraction and fuzzy comprehensive evaluation. The results indicate that only the ore samples 1, 2, 6 and 9 have obvious self-heating phenomenon, and their self-heating initiative temperatures are 220 ℃, 239 ℃, 220 ℃ and 220 ℃, respectively, which means that they are difficult to produce self-heating under normal mining conditions. The correlation dimension of self-heating process is fraction and the maximum Lyapunov exponent is positive, which means that it is feasible to study the self-heating process based on chaotic dynamics theory. The nonlinearities of self-heating process of these four samples （ore samples 1, 2, 6 and 9） are 0.8227, 0.7521, 0.9401 and 0.8827 respectively and the order of the samples according to these results is： sample 6, sample 9, sample 1, sample 2, which is consistent with the measured results of self-heating characteristics. Therefore, the nonlinearity method can be used to evaluate the self-heating tendency of sulfide ores, and it is an effective verification of the reliability of measured results.展开更多
Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching t...Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching temperature and reaction time on leaching process were explored. The leaching efficiency of Gabonese manganese oxide ore reached almost 100% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 2.5 molFL, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching efficiency of Xiangxi manganese oxide ore reached 99.8% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 1.7 mol/L, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching process followed the internal diffusion controlled kinetic model, and the apparent activation energies of Gabonese manganese oxide ore and Xiangxi manganese oxide ore were calculated to be 38.2 kJ/mol and 20.4 kJ/mol, respectively. The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of XRD analysis and SEM analysis.展开更多
Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leachi...Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5：1.展开更多
The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to ...The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to solid ratio（L/S ratio）, stirring speed, leaching temperature, leaching time and H2SO4 concentration on the leaching rates of Mn and Fe during the reduction–acid leaching process were discussed. The leaching rates of 96.47% for Mn and 19.24% for Fe were obtained under the optimized conditions of mass ratio of Ca S to manganese oxide ore 1：6.7, L/S ratio 5：1, stirring speed 300 r/min, reduction temperature of 95 °C for 2.0 h in the reduction process and leaching stirring speed of 200 r/min, H2SO4 concentration of 1.5 mol/L, leaching temperature of 80 °C for 5 min in the leaching process. In addition, this process can be employed in the recovery of manganese from various manganese oxide ores, and Mn leaching rate above 95% is obtained.展开更多
A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore ma...A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore mass ratio, and roasting temperature on Cr and Al extraction were studied. Experimental results indicate that the extraction rates of Cr and Al are up to 99%and 82%, respectively, under the optimal particle size of 44–74μm, Na2CO3-to-ore mass ratio of 0.6：1, and temperature of 1000 ℃. Dechromization within the range of 600–800 oC is controlled by the diffusion through the product layer with an apparent activation energy of 3.9 kJ/mol, and that it is controlled by the chemical reaction at the surface within the range of 900–1100 ℃ with an apparent activation energy of 54.3 kJ/mol. Besides, the Avrami diffusion controlled model with on apparent activation energy of 16.4 kJ/mol is most applicable for dealumination. Furthermore, 96.8%Ni and 95.6%Co could be extracted from the alkali-roasting residues in the subsequent pressure acid leaching process.展开更多
A logic fault tree of mine spontaneous combustion of sulphide ores was built by the fault tree analysis (FTA) based on a lot of mechanism investigation of sulphide ore spontaneous combustion in more than ten mines an...A logic fault tree of mine spontaneous combustion of sulphide ores was built by the fault tree analysis (FTA) based on a lot of mechanism investigation of sulphide ore spontaneous combustion in more than ten mines and review of a great amount of relevant展开更多
An ore-blending optimization model for the sintering process is an intelligent system that includes iron ore characteristics, expert knowledge and material balance. In the present work, 14 indices are proposed to repr...An ore-blending optimization model for the sintering process is an intelligent system that includes iron ore characteristics, expert knowledge and material balance. In the present work, 14 indices are proposed to represent chemical composition, granulating properties and high temperature properties of iron ores. After the relationships between iron ore characteristics and sintering performance are established, the ＂two-step＂ method and the simplex method are introduced to build the model by distinguishing the calculation of optimized blending proportion of iron ores from that of other sintering materials in order to improve calculation efficiency. The ore-blending optimization model, programmed by Access and Visual Basic, is applied to practical production in steel mills and the results prove that the present model can take advantage of the available iron ore resource with stable sinter yield and quality performance but at a lower cost.展开更多
Ion adsorption type rare earth ores(IATREOs)are a valuable strategic mineral resource in China,which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth(RE)element...Ion adsorption type rare earth ores(IATREOs)are a valuable strategic mineral resource in China,which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth(RE)elements.In the leaching process for recovering rare earth elements from IATREOs,many impurities will be leached together with rare earth elements and enter the leaching liquor.An impurity removal-precipitation enrichment technique is currently applied to selectively recovery rare earth elements from the leaching liquor with the high content of impurities and low concentration of rare earth elements by using ammonium bicarbonate in the industry.However,a high loss of rare earth elements and severe ammonia nitrogen pollution are caused by this process.Therefore,more beneficial impurities removal technologies,mainly for aluminum,and green enrichment technologies with lower pollution are now urgently needed.For this purpose,this paper analyzed two aspects of research progress in recent decades:the green separation of rare earth elements and aluminum from leaching liquor and the green and efficient enrichment of rare earth elements.Finally,an approach for the high-efficiency and green enrichment of rare earth elements from leaching liquor of the IATREOs is proposed in several aspects,including impurity inhibition leaching,neutralization and impurity removal,alkaline calcium and magnesium salt precipitation enrichment,and centrifugal extraction enrichment.展开更多
基金Project supported by the Thousand Talents Program of Jiangxi Province,China(JXSQ2023201003)National Natural Science Foundation of China(42107254)+4 种基金Science and Technology Major Program of Ordos City(2022EEDSKJZDZX014-2)Technological Innovation Guidance Program of Jiangxi Province(20212BDH81029)Rare Earth Industry Fund(IAGM2020DB06)Selfdeployed Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E055A01)the Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-3-3)。
文摘The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with the advantage of being environmental-friendly.As one of the organic acids produced by biological metabolism,citric acid was used to leach REEs and explore the performance and process.The results demonstrate that citric acid exhibits higher leaching efficiency(96.00%)for REEs at a relatively low concentration of 0.01 mol/L compared with(NH_(4))_(2)SO_(4)(84.29%,0.1 mol/L)and MgSO_(4)(83.99%,0.1 mol/L).Citric acid shows a preference for leaching heavy rare earth elements,with 99%leaching efficiency in IAREO,which shows higher capacity than(NH_(4))_(2)SO_(4)and MgSO_(4)(as inorganic leaching agents).Kinetic analysis indicates that the leaching process of REEs with citric acid is controlled by both the internal diffusion kinetics and chemical reaction kinetics,which is different from inorganic leaching agents.Visual Minteq calculations confirm that RE-Citrate is the main constituent of the extract solution in the leaching process of the IAREO,thereby enhancing the leaching efficiency of REEs from the IAREO.It suggests that citric acid may be used as a promising organic leaching agent for the environmentalfriendly extraction of REEs from IAREO.
基金Project supported by the National Natural Science Foundation of China(U2002215)。
文摘Weathered crust elution-deposited rare earth ores(WREOs)are rich in medium and heavy rare earth.In order to improve the in-situ leaching process,which is prone to landslides and poor permeability,cationic hydroxyethyl cellulose(PQ-10)was used as a novel green swelling inhibitor and percolation promoter and was mixed with conventional leaching agent ammonium sulfate((NH_(4))_(2)SO_(4))to form a composite leaching agent to study the performance and mechanism of swelling inhibition and percolation promotion.Adding PQ-10 can inhibit the hydration swelling of WREOs,promote the percolation effect of the leaching agent,improve the rare earth(RE)leaching efficiency,and reduce the im purity aluminum(Al)leaching efficiency.Compared with the conventional leaching agent 2 wt%(NH_(4))_(2)SO_(4),the percolation time is reduced by 50%by using the composite leaching agent(0.02 wt%PQ-10+2 wt%(NH_(4))_(2)SO_(4)).PQ-10 has positively charged quaternary ammonium groups and hydrophilic group hydroxyl groups,which makes it easy to adsorb on WREOs multiple sites through electrostatic interaction and hydrogen bonding,weakening the electrostatic repulsion between mineral particles,reducing the WREOs interlayer spacing,compressing the double electric layer thickness at the solid-liquid interface,weakening the mineral hydration swelling and increasing the percolation rate.The long carbon chains of the polymer entangle and link the fine mineral particles to agglomerate them,increasing their particle size and reduc ing their hydration dispersion,and preventing blockage of the pe rcolation pores caused by migration of the fine particles through the ore body with the solution.PQ-10 molecules also insert the mine ral interlayer and expulsion of the internal water,further inhibiting the swelling of WREOs.Adding PQ-10 reduces the surface tension of(NH_(4))_(2)SO_(4)solution,improving the spreading and spreading ability of the solution,reducing the adhesion work between molecules in the solid-liquid phase and the adhesion work reduction factor.It proves that PQ-10 promotes the percolation effect of the leaching process of WREOs.In addition,PQ-10 expands the leaching pore size and seepage channels,further improving the percolation rate.
文摘Stainless steel,known for its exceptional properties and diverse applications,conventionally requires a multistage process that generates considerable CO_(2) emissions by using fossil-based carbon reductants.This study investigated hydrogen plasma smelting reduction as a novel,sustainable,and efficient method for producing stainless steel directly from lateritic nickel and chromite ores.The research aimed to examine the effect of ore proportion on AISI 300 series stainless steel production and assess the reduction process over time through thermochemical calculations and experimental studies.Results showed that increasing the proportion of chromite ore in the feed raises Cr content and reduces Ni content in metals while increasing Cr_(2)O_(3) and Al_(2)O_(3) content in oxides.A briquette comprising 30wt%chromite ore and 70wt%calcined nickel ore yields better results for AISI 300 stainless steel,with Fe,Cr,Ni,and Si content of 62.95wt%,19.37wt%,11.83wt%,and 0.72wt%,respectively,after 180 s of hydrogen plasma exposure.Nearly all NiO compounds are converted into Ni after 60 s of smelting reduction,whereas FeO compounds are almost fully converted into Fe after 120 s of smelting reduction.AISI 300 series stainless steel is successfully produced after 120 s of reduction,achieving Fe,Cr,Ni,and Si content of 64.36wt%,21.92wt%,10.08wt%,and 0.61wt%,respectively.Process optimization remains promising because the Cr_(2)O_(3) content in the slag is still relatively high at 15.52wt%.This ultrafast and direct production method holds considerable potential to transform stainless steel production by reducing environmental impact and enhancing process efficiency.Specifically,the method eliminates the use of an argon oxygen decarburization converter and vacuum oxygen decarburization in stainless steelmaking.
基金supports from the National Key R&D Program of China(No.2022YFC3901404)the Natural Science Foundation of Chongqing,China(No.CSTB2023NSCQ-BHX0166)the Fundamental Research Funds for the Central Universities,China(No.2023CDJXY-016)are sincerely acknowledged.
文摘The semi-molten smelting process of a mixture of saprolitic and limonitic laterite ores was systematically investigated and the effect of slag basicity was deeply analyzed.The results indicate that the slag system can be located in the liquidus region of low melting-point diopside(CaMgSi_(2)O_(6))when slag basicity is kept at 0.3 and limonitic laterite mass fraction is not less than 10%.When the reduction temperature,C/O mass ratio,limonitic laterite mass fraction and slag basicity are kept at the optimum values of 1300℃,0.86,20%and 0.3,respectively,ferronickel products with grades 6.42%Ni and 86.99%Fe are prepared.The recovery rates of Ni and Fe reach 88.60%and 72.25%,respectively.
基金supported by the Department of science and technology of Shaanxi Province(NO.2023-ZDLGY-24).
文摘Detection of ore waste is crucial for achieving automation in mineral metallurgy production.However,deep learning-based target detection algorithms still face several challenges in iron waste screening,including poor lighting conditions in underground mining environments,dust disturbances,platform vibrations during operation,and limited resources for large-scale computing equipment.These factors contribute to extended computation times and unsatisfactory detection accuracy.To address these challenges,this paper proposes an ore waste detection algorithm based on an improved version of YOLOv5.To enhance feature extraction capabilities,the RepLKNet module is incorporated into the YOLOv5 backbone and neck networks.This module enhances the deformation information of feature extraction with the maximum effective Receptive Field to increase the model's accuracy.The Normalizationbased Attention Module(NAM)was introduced to enhance the attention mechanism by focusing on the most relevant features.This improves accuracy in detecting objects against noisy or unclear backgrounds,thereby further enhancing detection performance while reducing model parameters.Additionally,the loss function is optimized to constrain angular deviation using the SIOU loss function,which prevents the training frame from drifting during training and enhances convergence speed.To validate the performance of the proposed method,we tested it using a self-constructed dataset comprising 1,328 images obtained from the crushing station at Jinchuan Group's No.2 mine.The results indicate that,compared to YOLOv5s on the self-constructed dataset,the proposed algorithm achieves an 18.3%improvement in mAP(0.5),a 54%reduction in FLOPs,and a 52.53%decrease in model parameters.The effectiveness and superiority of the proposed algorithm are demonstrated through case studies and comparative analyses.
基金financially supported by the National Key Research and Development Program of China(No.2021YFC2901000)the National Natural Science Foundation of China(No.52104249)+1 种基金the Liaoning Joint Fund General Support Program Project(No.2023-MSBA-126)the Fundamental Research Funds for the Central Universities(No.N2401019)。
文摘As a refractory iron ore,the clean and efficient beneficiation of limonite is crucial for ensuring a sustainable long-term supply of iron metal.In this study,the microwave fluidization magnetization roasting of limonite was explored.The micromorphology,microstructure,and mineral phase transformation of the roasted products were analyzed using a scanning electron microscope,an automatic surface area and porosity analyzer,an X-ray diffractometer,and a vibrating sample magnetometer.Kinetic analysis was also conducted to identify the factors limiting the roasting reaction rate.Microwave fluidization roasting significantly increased the specific surface area of limonite,increased the opportunity of contact between CO and limonite,and accelerated the transformation from FeO(OH)toα-Fe_(2)O_(3)and then to Fe_(3)O_(4).In addition,the water in the limonite ore and the newly formed magnetite exhibited a strong microwave absorption capacity,which has a certain activation effect on the reduction roasting of limonite.The saturation magnetization and maximum specific magnetization coefficient increased to 23.08 A·m^(2)·kg^(-1)and 2.50×10^(-4)m^(3)·kg^(-1),respectively.The subsequent magnetic separation of the reconstructed limonite yielded an iron concentrate with an Fe grade of 59.26wt%and a recovery of 90.07wt%.Kinetic analysis revealed that the reaction mechanism function model was consistent with the diffusion model(G(α)=α^(2)),with the mechanism function described as k=0.08208exp[-20.3441/(R_(g)T)].Therefore,microwave fluidization roasting shows significant potential in the beneficiation of limonite,offering a promising approach for the exploitation of refractory iron ores.
基金Project supported by the National Natural Science Foundation of China(22078252,51874212,52274266)。
文摘Weathered crust elution-deposited rare earth ores(WREOs)in China are the main source of medium and heavy rare earths in the world.In order to improve the seepage and the mass transfer of traditional ammonium salt leaching process of WREOs,surfactants were added in the ammonium sulfate leaching solution and the ammonium chloride leaching solution.The leaching kinetics,the mass transfer process,and the adhesion work reduction factor calculated from the interfacial properties were studied to reveal the strengthening mechanism of surfactant.In the presence of the tested five surfactants,cetyl trimethyl ammonium bromide(CTAB),dodecyl trimethyl ammonium bromide(DTAB),sodium dodecyl sulfate(SDS),sodium oleate and oleic acid,the permeability of WREOs is improved,the rare earth(RE)leaching efficiency increase and the impurity aluminum(Al)leaching efficiency decrease,indicating its promotional effect on the leaching process of WREOs.Furthermore,CTAB shows a better leaching enhancement,and the optimal addition dosage is 0.4 g/L for the two ammonium salt leaching agent systems.The kinetics analysis shows the internal diffusion controls model of RE and Al leaching process,and the leaching kinetics equations of RE and Al related to CTAB concentration were obtained for the two ammonium salt leaching systems.According to the chromatographic plate theory,the mass transfer efficiency of RE increases with the CTAB concentration increasing until 0.4 g/L,which confirms that the optimal CTAB addition is 0.4 g/L.Smaller adhesion work and adhesion work reduction factor indicate more favorable permeation as well as the leaching process.
基金supported by the National Natural Science Foundation of China(Grant No.52274290)the Basic Science Center Project for the National Natural Science Foundation of China(No.72088101).
文摘Super-high bed sintering process is an important development direction of iron ore sintering for its lower emission and higher yield.However,there is a lack of deep understanding of the uneven quality of super-high bed sintering products,and the deterioration of reduction disintegration performance,the thickening of hearth layer and the reduction in energy-saving effect are perplexing enterprises and researchers.To ascertain the problems of super-high bed sintering,ten sintering machines with the areas of 265,280,360,550 and 660 m^(2)and bed depth above 900 mm were sampled and analyzed.The results showed that problems were mainly shown in the unevenness of chemical composition,macrostructure,mechanical strength and metallurgical performance.The chemical composition exhibits severe segregation in both horizontal and vertical directions,with basicity segregation reaching as high as 0.81.The uneven macrostructure of sinter is reflected in a 10%difference in porosity and mechanical strength increase in 16%–19%along the vertical direction.The reducibility and reduction disintegration performance gradually deteriorate along the bed depth,with a difference of 10.5%in reducibility and 7.3%in RDI−0.5 mm(reduction disintegration index of sinter with size smaller than 0.5 mm).
基金This work was supported by the National Natural Science Foundation of China(Grant No.52274290).
文摘The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous research.To inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were executed.The results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,respectively.From the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 mm.Fluxes and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm ones.The heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel distribution.The inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid phase.The inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing results.Homogeneous mineralizing condition is the key for homogeneous super-high bed sintering.
基金accomplished in accordance with the Research Program of the Geological Institute of the Russian Academy of Sciences。
文摘Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were studied.Received data on the composition of REE exhibit both the distinct negative(Ce/Ce*_(PAAS)<1)and positive(Ce/Ce*_(PAAS)>1)cerium anomalies and the positive Eu-anomaly(Eu/Eu*_(PAAS)>1).Negative Eu-anomalies are not observed.The contents of Mn,Fe,REE,and Ce-anomalies show a positive correlation with each other.Ce-anomalies and the amount of manganese and REE in relation to the carbon isotope composition(δ^(13)C)show a negative relationship and indicate that oxidized carbon of organic matter played an important role in the concentration of manganese and REE in manganese ores.The chemical and isotope composition of examined rocks indicates on secondary formation of Mnores.Two major phases and sources are distinguished in the ore-forming process characterized by diff erent chemical(REE and ore elements)and isotope composition:(i)highgrade manganese ores(with high contents of REE and light carbon isotope composition)and(ii)low-grade manganese ores(with low contents of REE and heavy carbon isotope composition).
基金Projects(51174062,51104036)supported by the National Natural Science Foundation of ChinaProject(2012BAE06B05)supported by the National Science and Technology Support Program of China during the 12th Five-Year Plan Period+1 种基金Projects(2012AA061502,2012AA061501)supported by the National High-Tech Research and Development Program of ChinaProjects(N120602006,N110302002,N110602005)supported by Fundamental Research Funds for the Central Universities of China
文摘Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward.
基金Project (51074181) supported by the National Natural Science Foundation of ChinaProject (2010ssxt241) supported by Precious Dissertation Innovation Foundation of Central South University, China
文摘The method of infrared thermography to predict the temperature of the sulfide ores has a large error. To solve this problem, the temperature of the sulfide ores is measured by thermal infrared imager and recording thermometric instrument contrastively. The main factors, including emissivity, distance, angle and dust concentration that affect the temperature measurement precision, are analyzed. The regression equations about the individual factors and comprehensive factors are obtained by analyzing test data. The application of the regression equations improves the precision of the thermal infrared imager. The geometric information lost in traditional infrared thermometry is determined by visualization grid method and interpolation method, the relationship between the infrared imager and geometry information is established. The geometry location can be measured exactly.
基金Project(51304238)supported by the National Natural Science Foundation of ChinaProject(JSK200206)supported by the Foundation of Key Laboratory of Mine Thermo-motive Disaster and Prevention,Ministry of Education,China
文摘In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials and their self-heating characteristics were measured in laboratory. Furthermore, the measured temperature was studied by integrating wavelet transform, nonlinear characteristic parameters extraction and fuzzy comprehensive evaluation. The results indicate that only the ore samples 1, 2, 6 and 9 have obvious self-heating phenomenon, and their self-heating initiative temperatures are 220 ℃, 239 ℃, 220 ℃ and 220 ℃, respectively, which means that they are difficult to produce self-heating under normal mining conditions. The correlation dimension of self-heating process is fraction and the maximum Lyapunov exponent is positive, which means that it is feasible to study the self-heating process based on chaotic dynamics theory. The nonlinearities of self-heating process of these four samples （ore samples 1, 2, 6 and 9） are 0.8227, 0.7521, 0.9401 and 0.8827 respectively and the order of the samples according to these results is： sample 6, sample 9, sample 1, sample 2, which is consistent with the measured results of self-heating characteristics. Therefore, the nonlinearity method can be used to evaluate the self-heating tendency of sulfide ores, and it is an effective verification of the reliability of measured results.
基金Project(2010FJ1011)supported by the Major Project of Hunan Science and Technology,ChinaProject(cstc2012ggB90002)supported by the Chongqing Key Science and Technology Program,China
文摘Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching temperature and reaction time on leaching process were explored. The leaching efficiency of Gabonese manganese oxide ore reached almost 100% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 2.5 molFL, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching efficiency of Xiangxi manganese oxide ore reached 99.8% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 1.7 mol/L, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching process followed the internal diffusion controlled kinetic model, and the apparent activation energies of Gabonese manganese oxide ore and Xiangxi manganese oxide ore were calculated to be 38.2 kJ/mol and 20.4 kJ/mol, respectively. The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of XRD analysis and SEM analysis.
基金Project (2007CB613604) supported by the National Basic Research Program of China
文摘Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5：1.
基金Project(21376273)supported by the National Natural Science Foundation of ChinaProject(2010FJ1011)supported by the Key Program of Science and Technology of Hunan Province,China
文摘The extraction of manganese from low-grade manganese oxide ores using Ca S derived from Ca SO4 as reductant was investigated. The effects of mass ratio of Ca S to ore, reduction temperature, reduction time, liquid to solid ratio（L/S ratio）, stirring speed, leaching temperature, leaching time and H2SO4 concentration on the leaching rates of Mn and Fe during the reduction–acid leaching process were discussed. The leaching rates of 96.47% for Mn and 19.24% for Fe were obtained under the optimized conditions of mass ratio of Ca S to manganese oxide ore 1：6.7, L/S ratio 5：1, stirring speed 300 r/min, reduction temperature of 95 °C for 2.0 h in the reduction process and leaching stirring speed of 200 r/min, H2SO4 concentration of 1.5 mol/L, leaching temperature of 80 °C for 5 min in the leaching process. In addition, this process can be employed in the recovery of manganese from various manganese oxide ores, and Mn leaching rate above 95% is obtained.
基金Project(51125018)supported by the National Natural Science Foundation for Distinguished Young Scholars of ChinaProject(51204153)supported by the National Natural Science Foundation of ChinaProject(2011BAC06B07)supported by the National High Technology Research and Development Program,China
文摘A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore mass ratio, and roasting temperature on Cr and Al extraction were studied. Experimental results indicate that the extraction rates of Cr and Al are up to 99%and 82%, respectively, under the optimal particle size of 44–74μm, Na2CO3-to-ore mass ratio of 0.6：1, and temperature of 1000 ℃. Dechromization within the range of 600–800 oC is controlled by the diffusion through the product layer with an apparent activation energy of 3.9 kJ/mol, and that it is controlled by the chemical reaction at the surface within the range of 900–1100 ℃ with an apparent activation energy of 54.3 kJ/mol. Besides, the Avrami diffusion controlled model with on apparent activation energy of 16.4 kJ/mol is most applicable for dealumination. Furthermore, 96.8%Ni and 95.6%Co could be extracted from the alkali-roasting residues in the subsequent pressure acid leaching process.
文摘A logic fault tree of mine spontaneous combustion of sulphide ores was built by the fault tree analysis (FTA) based on a lot of mechanism investigation of sulphide ore spontaneous combustion in more than ten mines and review of a great amount of relevant
文摘An ore-blending optimization model for the sintering process is an intelligent system that includes iron ore characteristics, expert knowledge and material balance. In the present work, 14 indices are proposed to represent chemical composition, granulating properties and high temperature properties of iron ores. After the relationships between iron ore characteristics and sintering performance are established, the ＂two-step＂ method and the simplex method are introduced to build the model by distinguishing the calculation of optimized blending proportion of iron ores from that of other sintering materials in order to improve calculation efficiency. The ore-blending optimization model, programmed by Access and Visual Basic, is applied to practical production in steel mills and the results prove that the present model can take advantage of the available iron ore resource with stable sinter yield and quality performance but at a lower cost.
基金Project supported by the National Key Research and Development Project of China(2020YFC1909002,2019YFC0605002)National Natural Science Foundation of China(51604128)+1 种基金The Youth Jinggang Scholars Program in Jiangxi Province(QNJG2019056)the Cultivation Project of the State Key Laboratory of Green Development and High-value Utilization of Ionic Rare Earth Resources in Jiangxi Province(20194AFD44003)。
文摘Ion adsorption type rare earth ores(IATREOs)are a valuable strategic mineral resource in China,which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth(RE)elements.In the leaching process for recovering rare earth elements from IATREOs,many impurities will be leached together with rare earth elements and enter the leaching liquor.An impurity removal-precipitation enrichment technique is currently applied to selectively recovery rare earth elements from the leaching liquor with the high content of impurities and low concentration of rare earth elements by using ammonium bicarbonate in the industry.However,a high loss of rare earth elements and severe ammonia nitrogen pollution are caused by this process.Therefore,more beneficial impurities removal technologies,mainly for aluminum,and green enrichment technologies with lower pollution are now urgently needed.For this purpose,this paper analyzed two aspects of research progress in recent decades:the green separation of rare earth elements and aluminum from leaching liquor and the green and efficient enrichment of rare earth elements.Finally,an approach for the high-efficiency and green enrichment of rare earth elements from leaching liquor of the IATREOs is proposed in several aspects,including impurity inhibition leaching,neutralization and impurity removal,alkaline calcium and magnesium salt precipitation enrichment,and centrifugal extraction enrichment.
