磁化焙烧是处理菱-赤混合型铁矿石最有效的手段,焙烧过程的动力学研究可为实现该类铁矿石磁化焙烧关键技术提供理论支撑。采用X射线衍射、自制热重分析炉、扫描电镜等途径对矿石磁化焙烧过程的动力学及焙烧产品的微观形貌进行了研究,结...磁化焙烧是处理菱-赤混合型铁矿石最有效的手段,焙烧过程的动力学研究可为实现该类铁矿石磁化焙烧关键技术提供理论支撑。采用X射线衍射、自制热重分析炉、扫描电镜等途径对矿石磁化焙烧过程的动力学及焙烧产品的微观形貌进行了研究,结果表明:矿石在焙烧过程中可不添加任何还原剂使菱铁矿和赤铁矿全部转变为磁铁矿,菱铁矿分解反应的发生是整个反应过程的限制性环节;在一定范围内增加焙烧温度,可使矿石的焙烧反应更加完全,同时有利于矿物在较短的时间内达到较高的反应速度,缩短反应完成所需要的时间。矿石磁化焙烧过程的机理函数符合随机成核与随后生长模型,表观活化能E和指前因子A分别为74.48 k J/mol、27.39 min-1。焙烧后产品表面有大量微裂纹产生,铁矿物与脉石矿物共生关系紧密,在后续选别作业前还需对其进行细磨,焙烧产品中Mg、Ca、Mn元素与Fe元素以类质同象形式共生,将影响最终铁精矿品位。展开更多
Iron and steel industry is an important sector of Iran's economy.Choghart iron ore mine is an important iron ore producer of Iran steel industry.Phosphorous contained in the iron ore concentrates of Choghart mine ...Iron and steel industry is an important sector of Iran's economy.Choghart iron ore mine is an important iron ore producer of Iran steel industry.Phosphorous contained in the iron ore concentrates of Choghart mine has a detrimental effect on the steel making process,whereby this causes cracks to form in the refractory lining of blast furnaces.In the past,about 1.43 Mt of low-grade and 4.53 Mt of high-phosphorous materials had been transported to low grade and high phosphorous stockpiles,respectively,for future beneficiation.As a result of the progressive depletion of high-grade ore and establishment of beneficiation plant in Choghart,exploitation of these two stockpiles in this mine became an important issue.In this work,a linear goal programming(GP) model was developed in order to determine the optimum iron ore blend in terms of quality from low grade and high phosphorous stockpiles of Choghart mine.The model was solved by the SOLVER V.9 program.Results show that feeding with acceptable quality(w(Fe)≥50% and w(P)≤1.2%,mass fraction) materials can be blended from stockpiles that satisfy the needs of the Choghart processing line.展开更多
Bacterial leaching of single sulfide minerals and polymetallic sulfide ores was operated in shake flasks and small-scaled columns.The results show that bioleaching of jamesonite is not accessible,the iron extraction r...Bacterial leaching of single sulfide minerals and polymetallic sulfide ores was operated in shake flasks and small-scaled columns.The results show that bioleaching of jamesonite is not accessible,the iron extraction rate of pyrrhotite bioleaching reaches 98.2% after 26 d,and the zinc extraction rate of marmatite bioleaching reaches 92.3%,while the corresponding iron extraction reaches only 13.6% after 29 d.Pulp density has a significant effect on metal extraction of pyrrhotite and marmatite bioleaching.The corresponding metal extraction rate decreases with the increase of pulp density.For the polymetallic sulfide ores,zinc extraction of 97.1% is achieved after bioleaching in shake flasks for 10 d,while only 7.8% is obtained after bioleaching in small-scaled column.Analytical results of scanning electron microscopy(SEM) and energy dispersive X-ray analysis(EDX) reveal that large amount of calcium sulfate is formed on the mineral surface.展开更多
文摘磁化焙烧是处理菱-赤混合型铁矿石最有效的手段,焙烧过程的动力学研究可为实现该类铁矿石磁化焙烧关键技术提供理论支撑。采用X射线衍射、自制热重分析炉、扫描电镜等途径对矿石磁化焙烧过程的动力学及焙烧产品的微观形貌进行了研究,结果表明:矿石在焙烧过程中可不添加任何还原剂使菱铁矿和赤铁矿全部转变为磁铁矿,菱铁矿分解反应的发生是整个反应过程的限制性环节;在一定范围内增加焙烧温度,可使矿石的焙烧反应更加完全,同时有利于矿物在较短的时间内达到较高的反应速度,缩短反应完成所需要的时间。矿石磁化焙烧过程的机理函数符合随机成核与随后生长模型,表观活化能E和指前因子A分别为74.48 k J/mol、27.39 min-1。焙烧后产品表面有大量微裂纹产生,铁矿物与脉石矿物共生关系紧密,在后续选别作业前还需对其进行细磨,焙烧产品中Mg、Ca、Mn元素与Fe元素以类质同象形式共生,将影响最终铁精矿品位。
文摘Iron and steel industry is an important sector of Iran's economy.Choghart iron ore mine is an important iron ore producer of Iran steel industry.Phosphorous contained in the iron ore concentrates of Choghart mine has a detrimental effect on the steel making process,whereby this causes cracks to form in the refractory lining of blast furnaces.In the past,about 1.43 Mt of low-grade and 4.53 Mt of high-phosphorous materials had been transported to low grade and high phosphorous stockpiles,respectively,for future beneficiation.As a result of the progressive depletion of high-grade ore and establishment of beneficiation plant in Choghart,exploitation of these two stockpiles in this mine became an important issue.In this work,a linear goal programming(GP) model was developed in order to determine the optimum iron ore blend in terms of quality from low grade and high phosphorous stockpiles of Choghart mine.The model was solved by the SOLVER V.9 program.Results show that feeding with acceptable quality(w(Fe)≥50% and w(P)≤1.2%,mass fraction) materials can be blended from stockpiles that satisfy the needs of the Choghart processing line.
基金Project(51374248) supported by the National Natural Science Foundation of ChinaProject(NCET-13-0595) supported by Program for New Century Excellent Talents in University,China+1 种基金Project(2012AA061501) supported by the National High Technology Research and Development Program of ChinaProject(20120162120010) supported by the Research Fund for the Doctoral Program of Higher Education of China
文摘Bacterial leaching of single sulfide minerals and polymetallic sulfide ores was operated in shake flasks and small-scaled columns.The results show that bioleaching of jamesonite is not accessible,the iron extraction rate of pyrrhotite bioleaching reaches 98.2% after 26 d,and the zinc extraction rate of marmatite bioleaching reaches 92.3%,while the corresponding iron extraction reaches only 13.6% after 29 d.Pulp density has a significant effect on metal extraction of pyrrhotite and marmatite bioleaching.The corresponding metal extraction rate decreases with the increase of pulp density.For the polymetallic sulfide ores,zinc extraction of 97.1% is achieved after bioleaching in shake flasks for 10 d,while only 7.8% is obtained after bioleaching in small-scaled column.Analytical results of scanning electron microscopy(SEM) and energy dispersive X-ray analysis(EDX) reveal that large amount of calcium sulfate is formed on the mineral surface.
