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81.
论述了预处理难选金矿细菌的种类、来源,浸出机理,浸出工艺及工业应用实践.归纳介绍了强化难选金矿细菌浸出的措施.  相似文献   
82.
马钢球团配用巴西PF精矿的工业试验及生产   总被引:3,自引:0,他引:3  
介绍了马钢一烧竖炉配用巴西PF精矿生产球团的效果。工业试验及生产实践表明,配用20%~30%PF精矿后,不但可以降低球团矿原料成本,解决球团原料紧张的难题,而且球团矿冶金性能完全满足高炉冶炼需要。  相似文献   
83.
The effect of addition of small amounts of aluminium on mechano‐chemical reduction of hematite by graphite was studied. Various amounts of aluminium (0 to 10%) were added to a hematite‐graphite mixture, in which C/O ratio was 1:1. The hematite‐graphite‐aluminium mixtures were then subjected to ball milling followed by heating up reduction. The heating up reduction was carried out in Ar atmosphere, using TG‐DTA device. In TG‐DTA experiments, samples were heated by a constant heating rate of 10 °C/min from room temperature up to 1100 °C and maintained for 30 minutes at this temperature. To clarify the reactions which took place during milling and heating up reduction, the samples were subjected to XRD examinations. It was found that the heat generated during exothermic reaction of aluminothermic reduction of hematite promoted the endothermic reaction of carbothermic reduction. In the course of heating up reduction, the carbothermic reaction occurred just after aluminothermic reaction. Increasing of aluminum content from 0 to 10% in 2 hours ball milled samples decreased the temperature of carbothermic reaction from 1020 °C to about 860 °C. The further ball milling of the samples up to 5 and 10 hours, for the samples containing 10 and 5% aluminium respectively, caused the decrease of the temperature of aluminothermic and carbothermic reactions to around the melting point of aluminium.  相似文献   
84.
A visible light active and stable photoelectrode has been developed by depositing a passivating layer of ZnS QDs on CdS QDs sensitized hematite photoelectrode (Hematite‐CdS/ZnS) for PEC generation of hydrogen. Photoelectrochemical properties, in terms of stability and efficiency, have been investigated on the various hematite photoelectrodes sensitized with CdS QDs and CdS/ZnS QDs by varying number of SILAR cycles. I–V characteristics show that two layers of ZnS QDs deposited over three layers of CdS could enhance PEC response of hematite and efficiency by a factor of 3 and 11 respectively. Chronoamperometry measurement ensures that after adding a layer of ZnS QDs, CdS sensitized hematite film turns out to be a stable photoelectrode in the electrolyte. Prepared photoelectrodes have been characterized by XRD, SEM, HRTEM and UV–Vis spectrophotometer for various structural, morphological and optical properties to analyze PEC results. Mott–Schottky analysis and incident photon to current conversion efficiency (IPCE) measurements of sensitized hematite photoelectrode supported the improved PEC response of CdS/ZnS QDs sensitized hematite thin films. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
85.
张树林  侯金刚  金世斌 《黄金》2013,34(2):47-49
热压氧化难浸金矿或金精矿的安全生产十分重要,反应釜是热压氧化的重要工艺环节。阐述分析了反应釜应用操作的安全危害因素,提出了防止反应釜发生事故的预防措施,供业内同行参考。  相似文献   
86.
鲕状赤铁矿微波碳热还原-磁选提铁脱磷实验研究   总被引:5,自引:4,他引:1  
何文浩  陈雯  王鑫  雷鹰  李雨 《矿冶工程》2019,39(5):92-94
采用微波碳热还原-磁选工艺对鲕状赤铁矿提铁脱磷进行了研究,考察了还原温度、碱度、添加剂用量和原矿粒度等因素对提铁脱磷效果的影响。结果表明,最佳还原条件为:还原温度1 150 ℃、碱度0.8、配碳量1.0、钠盐添加剂用量15%、原矿粒度0.15 mm;将还原所得球团磨至-0.15 mm,在65 mT磁场强度下磁选,可得到全铁含量87.98%、铁回收率95.48%、脱磷率69.42%的指标。  相似文献   
87.
Recent increase in energy demand and associated environmental degradation concern has triggered more research towards alternative green energy sources. Eco‐friendly energy in facile way has been generated from abundantly available iron oxides using only few microliters of water without any external energy source. Hydroelectric cell (HEC) compatible to environment benign, low cost oxygen‐deficient mesoporous hematite nanoparticles has been used for splitting water molecules spontaneously to generate green electricity. Hematite nanoparticles have been synthesized by coprecipitation method. Chemidissociated hydroxyl group presence on hematite surface has been confirmed by infrared spectroscopy (IR) and X‐ray photoelectron spectroscopy (XPS). Surface oxygen vacancies in nanostructured hematite have been identified by transmission electron microscopy (TEM), XPS, and photoluminescence (PL) measurement. Hematite‐based HEC delivers 30 mA current with 0.92 V emf using approximately 500 μL water. Maximum off‐load output power 27.6 mW delivered by 4.84 cm2 area hematite‐based HEC is 3.52 times higher than reported 7.84 mW power generated by Li‐magnesium ferrite HEC. Electrochemistry of HEC in different irreversible polarization loss regions has been estimated by applying empirical modeling on V‐I polarization curve revealing the reaction and charge transport mechanism of cell. Tafel slope 22.7 mV has been calculated by modeling of activation polarization overvoltage region of 0.11 V. Low activation polarization indicated easy charge/ion diffusion and faster reaction kinetics of Ag/Zn electrode owing to lesser energy barrier at interface. Dissociated H3O+ ions diffuse through surface via proton hopping, while OH? ions migrate through interconnected defective crystallite boundaries resulting into high output cell current.  相似文献   
88.
段桂山 《工业炉》2012,34(3):50-51
高温耐火纤维整体拼装作为一种先进的材料和技术,在轧钢加热炉炉顶上运用比传统的耐火材料炉顶有着显著的优点,能大幅度延长炉顶的使用寿命,减少加热炉的热损失,缩短加热炉炉顶的检修时间,提高炉子生产率。  相似文献   
89.
Hematite pellet is required to be indurated at very high temperature to achieve its good strength as there is no exothermic heat of oxidation unlike magnetite. As mill scale contains mainly FeO and Fe3O4, any minor amount of its addition in pellet can provide in situ heat and enhance diffusion bonding and sintering. In this study, the mill scale generated in steel plant is added as magnetite input in hematite pellet both in acidic and in basic condition. It has been found that in fluxed pellet, mill scale can improve the properties of pellet. In acidic pellet, the induration temperature has been reduced to a great extent (1250–1275°C) and all properties have been found to be improved due to the addition of 15% mill scale. Mill scale shows enough potential to eliminate the flux addition in producing blast furnace quality pellet from hematite ore. Thus, the flux free acidic pellet has been developed even at very low temperature (1275°C) of induration.  相似文献   
90.
针对湿法气流床气化炉耐火材料损耗严重的问题,从块状剥落、烧蚀损伤、冲蚀损伤、化学侵蚀4方面进行了原因分析,提出可以通过合理选煤、改善工艺、合理选材及精心筑炉等手段延长耐火砖寿命。  相似文献   
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