In order to offer high grade concentrate to produce alumina by Bayer, the reverse-flotation technology of bauxite was investigated. The results show that sodium hexmetaphosphate has different depression on the flotati...In order to offer high grade concentrate to produce alumina by Bayer, the reverse-flotation technology of bauxite was investigated. The results show that sodium hexmetaphosphate has different depression on the flotation of diaspore and kaolinite. The recoveries of diaspore decrease markedly with the increase of the concentration of sodium hexmetaphosphate with dodecyl-amine as collector. Fourier transform infrared spectra indicate that the absorbance band 875cm -1 of the asymmetric stretching vibration of bridge oxygen P—O—P shifts to 880cm -1 , and the 1264cm -1 of the asymmetric stretching vibration of the bridge PO2 shifts to 1267cm -1 in the diaspore’s spectra. This demonstrates that sodium hexmetaphosphate interacts through bridging PO2 groups with the Al atoms exposed on the diaspore and kaolinite surfaces to form P—O—Al bond. Adsorption measurements also testify that sodium hexmetaphosphate adsorbs easily on the surface of diaspore. The adsorption density of PO-3 on the surface of diaspore is about 4.7×10 -6 mol/m2, while that on the kaolinite is only about 3.5×10 -7 mol/m2 when pH value is 6.展开更多
In this work,the reflux classifier with closely spaced inclined channels is used as the pre-concentration facility to improve the separation efficiency before the shaking table separation.Three operating parameters of...In this work,the reflux classifier with closely spaced inclined channels is used as the pre-concentration facility to improve the separation efficiency before the shaking table separation.Three operating parameters of reflux classifier(RC)to pre-concentrate fine(0.023−0.15 mm)tailings of antimony oxide were optimized by response surface methodology(RSM)using a three-level Box-Behnken design(BBD).The parameters studied for the optimization were feeding speed,underflow,and ascending water speed.Second-order response functions were produced for the Sb grade and recovery rate of the concentrate.Taking advantage of the quadratic programming,when the factors of feeding,underflow and ascending water are respectively 225,30 and 133 cm^3/min,a better result can be achieved for the concentrate grade of 2.31% and recovery rate of 83.17%.At the same time,70.48% of the tailings with the grade of 0.20% were discarded out of the feeding.The results indicated that the reflux classifier has a good performance in dealing with fine tailings of antimony oxide.Moreover,second-order polynomial equations,ANOVA,and three-dimensional surface plots were developed to evaluate the effects of each parameter on Sb grade and recovery rate of the concentrate.展开更多
Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studi...Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studied. The numerical simulation results show that 0.15–0.06 mm fine magnetite powder can decrease the disturbances caused by the bubbles. This is beneficial to the uniformity of the gas-solid interactions and thus to the uniformity and stability of the bed density and height. The experimental results show that, with an increase in the fine coal content in medium solids, both the fluidization quality and the beneficiation performance of the bed decreased gradually. When the fine coal content was no more than 13%, a relatively high superficial gas velocity increased the beneficiation efficiency. When the content was more than 13%, part of the fine coal was separated, leading to product layers. The separation efficiency was therefore gradually decreased. The models for predicting the bed density standard deviation and the probable error, E, value were both proposed. The E value can reach to 0.04–0.07 g/cm^3 under the optimized experimental parameters. This work provides a foundation for the adjustment of the bed density and the separation performance of the modularized 40–60 ton per hour dry coalbeneficiation industrial system.展开更多
Based on engineering reliability of large complex system and distinct characteristic of soft system, some new conception and theory on the medium elements and the associated system are created. At the same time, the r...Based on engineering reliability of large complex system and distinct characteristic of soft system, some new conception and theory on the medium elements and the associated system are created. At the same time, the reliability logic model of associated system is provided. In this paper, through the field investigation of the trial operation, the engineering reliability of the paste fill system in No 2 mine of Jinchuan Non ferrous Metallic Corporation is analyzed by using the theory of associated system.展开更多
The relationship between viscosity/yield stress and flotation rate in different chalcopyrite and lizardite concentrations was investigated by zeta potential measurements,rheological tests,flotation experiments,and Der...The relationship between viscosity/yield stress and flotation rate in different chalcopyrite and lizardite concentrations was investigated by zeta potential measurements,rheological tests,flotation experiments,and DerjguinLandau-Verwey-Overbeek theoretical calculation.Results indicated that the concentration of minerals would affect the viscosity and yield stress of the slurry.That is,the viscosity/yield stress in the slurry rises accordingly when the concentration of minerals increases.The increase in viscosity/yield stress in slurry is also unfavorable to the enrichment of chalcopyrite but is conducive to the entrainment of lizardite in either single or binary system.Specifically,the flotation rate of chalcopyrite decreases while that of lizardite increases with the rise in viscosity/yield stress.展开更多
On the basis of the mineralizing mechanism of froth cyclone, this paper expounds that the froth cyclone flotation process is accomplished in a limited centrifugal field. The main feature of air bubble mineralizing in ...On the basis of the mineralizing mechanism of froth cyclone, this paper expounds that the froth cyclone flotation process is accomplished in a limited centrifugal field. The main feature of air bubble mineralizing in the froth cyclone is a synthetic mineralizing process, of which the non collision mineralization of minute air bubble separated out dominates, supplemented with the collision mineralization. Moreover, this paper points out that the hydrophobic separated out and centrifugal force strengthen the selectivity of fine coal particle, accelerate the flotation speed and improve the slime recovery.展开更多
In this paper on the basis of studying the distribution of fine Coal in the dense medAn fluidised bed. the optimai size range of fine coal, which constitutes a fluidized bed together with the dense medium, has been fo...In this paper on the basis of studying the distribution of fine Coal in the dense medAn fluidised bed. the optimai size range of fine coal, which constitutes a fluidized bed together with the dense medium, has been found. In the separating process the fine coal will continuously aeeumulate in fluidized bed, thus inevitably reducing the density of the bed.In order to keep bed density stable, the authors adopted such measures as split-now of used medium and complement of fresb dense medium.The experiment results in both lab and pilot systems of the air-dense medium fluidized bed show that these measures are effective and satisfactory. Then authors also have estabinbed some relative dynamic mathematical models for it.展开更多
A 40-60 t/h modularized dry coal beneficiation process with a novel method to control the bed was designed around a gas-solid fluidized bed separator. Furthermore, the hydrodynamics of medium-solids consisting of wide...A 40-60 t/h modularized dry coal beneficiation process with a novel method to control the bed was designed around a gas-solid fluidized bed separator. Furthermore, the hydrodynamics of medium-solids consisting of wide-size-range magnetite powder （0.3-0.06 ram） and 〈1 mm fine coal were numerically studied. The simulation results show that the fluidization performance of the wide-size-range medium-solid bed is good. The separation performance of the modularized system was then investigated in detail using a mixture of 〈0.3 mm magnetite powder （mass fraction of 0.3-0.06 mm particles is 91.38 %） and 〈1 mm fine coal as solid media. The experimental results show that at separation densities of 1.33 g/cm^3 or 1.61 g/cm^3, 50-6 mm coal can be separated effectively with probable error, E, values of 0.05 g/cm^3 and 0.06 g/cm^3, respectively. This technique is beneficial for saving water resources and for the clean utilization of coal.展开更多
文摘In order to offer high grade concentrate to produce alumina by Bayer, the reverse-flotation technology of bauxite was investigated. The results show that sodium hexmetaphosphate has different depression on the flotation of diaspore and kaolinite. The recoveries of diaspore decrease markedly with the increase of the concentration of sodium hexmetaphosphate with dodecyl-amine as collector. Fourier transform infrared spectra indicate that the absorbance band 875cm -1 of the asymmetric stretching vibration of bridge oxygen P—O—P shifts to 880cm -1 , and the 1264cm -1 of the asymmetric stretching vibration of the bridge PO2 shifts to 1267cm -1 in the diaspore’s spectra. This demonstrates that sodium hexmetaphosphate interacts through bridging PO2 groups with the Al atoms exposed on the diaspore and kaolinite surfaces to form P—O—Al bond. Adsorption measurements also testify that sodium hexmetaphosphate adsorbs easily on the surface of diaspore. The adsorption density of PO-3 on the surface of diaspore is about 4.7×10 -6 mol/m2, while that on the kaolinite is only about 3.5×10 -7 mol/m2 when pH value is 6.
基金Project(2015SK20792)supported by Key Province Key Technology Research and Development Program of the Ministry of Science and Technology of Hunan,ChinaProjects(2019zzts703,2020zzts740,2020zzts202)supported by the Fundamental Research Funds for the Central Universities of ChinaProject(2020P4FZG03A)supported by State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization,China。
文摘In this work,the reflux classifier with closely spaced inclined channels is used as the pre-concentration facility to improve the separation efficiency before the shaking table separation.Three operating parameters of reflux classifier(RC)to pre-concentrate fine(0.023−0.15 mm)tailings of antimony oxide were optimized by response surface methodology(RSM)using a three-level Box-Behnken design(BBD).The parameters studied for the optimization were feeding speed,underflow,and ascending water speed.Second-order response functions were produced for the Sb grade and recovery rate of the concentrate.Taking advantage of the quadratic programming,when the factors of feeding,underflow and ascending water are respectively 225,30 and 133 cm^3/min,a better result can be achieved for the concentrate grade of 2.31% and recovery rate of 83.17%.At the same time,70.48% of the tailings with the grade of 0.20% were discarded out of the feeding.The results indicated that the reflux classifier has a good performance in dealing with fine tailings of antimony oxide.Moreover,second-order polynomial equations,ANOVA,and three-dimensional surface plots were developed to evaluate the effects of each parameter on Sb grade and recovery rate of the concentrate.
基金financially supported by the National Program on Key Basic Research Project of China (No.2012CB214904)the National Natural Science Foundation of China (Nos.51221462,51134022 and 51174203)
文摘Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studied. The numerical simulation results show that 0.15–0.06 mm fine magnetite powder can decrease the disturbances caused by the bubbles. This is beneficial to the uniformity of the gas-solid interactions and thus to the uniformity and stability of the bed density and height. The experimental results show that, with an increase in the fine coal content in medium solids, both the fluidization quality and the beneficiation performance of the bed decreased gradually. When the fine coal content was no more than 13%, a relatively high superficial gas velocity increased the beneficiation efficiency. When the content was more than 13%, part of the fine coal was separated, leading to product layers. The separation efficiency was therefore gradually decreased. The models for predicting the bed density standard deviation and the probable error, E, value were both proposed. The E value can reach to 0.04–0.07 g/cm^3 under the optimized experimental parameters. This work provides a foundation for the adjustment of the bed density and the separation performance of the modularized 40–60 ton per hour dry coalbeneficiation industrial system.
文摘Based on engineering reliability of large complex system and distinct characteristic of soft system, some new conception and theory on the medium elements and the associated system are created. At the same time, the reliability logic model of associated system is provided. In this paper, through the field investigation of the trial operation, the engineering reliability of the paste fill system in No 2 mine of Jinchuan Non ferrous Metallic Corporation is analyzed by using the theory of associated system.
基金Project(2018TP1002)supported by the Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources,ChinaProject(2019zzts994)supported by the Central South University Graduate Research and Innovation Project,China。
文摘The relationship between viscosity/yield stress and flotation rate in different chalcopyrite and lizardite concentrations was investigated by zeta potential measurements,rheological tests,flotation experiments,and DerjguinLandau-Verwey-Overbeek theoretical calculation.Results indicated that the concentration of minerals would affect the viscosity and yield stress of the slurry.That is,the viscosity/yield stress in the slurry rises accordingly when the concentration of minerals increases.The increase in viscosity/yield stress in slurry is also unfavorable to the enrichment of chalcopyrite but is conducive to the entrainment of lizardite in either single or binary system.Specifically,the flotation rate of chalcopyrite decreases while that of lizardite increases with the rise in viscosity/yield stress.
文摘On the basis of the mineralizing mechanism of froth cyclone, this paper expounds that the froth cyclone flotation process is accomplished in a limited centrifugal field. The main feature of air bubble mineralizing in the froth cyclone is a synthetic mineralizing process, of which the non collision mineralization of minute air bubble separated out dominates, supplemented with the collision mineralization. Moreover, this paper points out that the hydrophobic separated out and centrifugal force strengthen the selectivity of fine coal particle, accelerate the flotation speed and improve the slime recovery.
文摘In this paper on the basis of studying the distribution of fine Coal in the dense medAn fluidised bed. the optimai size range of fine coal, which constitutes a fluidized bed together with the dense medium, has been found. In the separating process the fine coal will continuously aeeumulate in fluidized bed, thus inevitably reducing the density of the bed.In order to keep bed density stable, the authors adopted such measures as split-now of used medium and complement of fresb dense medium.The experiment results in both lab and pilot systems of the air-dense medium fluidized bed show that these measures are effective and satisfactory. Then authors also have estabinbed some relative dynamic mathematical models for it.
基金Projects(50921002, 50774084) supported by the National Natural Science Foundation of ChinaProject(2007AA05Z318) supported by the National High-tech Research and Development Program of China+1 种基金Project(BK2010002) supported by the Natural Science Foundation of Jiangsu Province of ChinaProject(20100480473) supported by the China Postdoctoral Science Foundation
文摘A 40-60 t/h modularized dry coal beneficiation process with a novel method to control the bed was designed around a gas-solid fluidized bed separator. Furthermore, the hydrodynamics of medium-solids consisting of wide-size-range magnetite powder （0.3-0.06 ram） and 〈1 mm fine coal were numerically studied. The simulation results show that the fluidization performance of the wide-size-range medium-solid bed is good. The separation performance of the modularized system was then investigated in detail using a mixture of 〈0.3 mm magnetite powder （mass fraction of 0.3-0.06 mm particles is 91.38 %） and 〈1 mm fine coal as solid media. The experimental results show that at separation densities of 1.33 g/cm^3 or 1.61 g/cm^3, 50-6 mm coal can be separated effectively with probable error, E, values of 0.05 g/cm^3 and 0.06 g/cm^3, respectively. This technique is beneficial for saving water resources and for the clean utilization of coal.
