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21.
为了探明动态氧化条件下含钛高炉熔渣中金属铁的聚集、长大及沉降行为,通过高温氧化实验研究氧化时间、空气搅拌强度和纯氧氧化对金属铁沉降的影响.此外,还研究动态氧化过程中熔渣的温度与黏度变化情况,计算金属铁在熔渣中的沉降速度.实验室与1200 kg中试实验结果表明,向熔渣鼓入氧化性气体,低价钛化合物减少,熔渣温度升高,黏度减低,促进金属铁聚集、长大和沉降分离.氧化时间过长,熔渣中(FeO)与低价钛化合物基本消失,金属铁回收率下降.氧化终点的判断应以保留一定含量(FeO)与低价钛为依据. 相似文献
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简要描绘了粘性泥沙浑液面沉降的物理图景,概括和分析了国内外学者在粘性泥沙浑液面沉速公式方面的研究成果,并指出了所存在的问题,在此基础上展望今后的研究工作。 相似文献
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Negative effects of dissolved organic compounds on settling performance of goethite in Bayer red mud
Goethite, a typical iron-containing monomineral in red mud, was synthesized under the simulated Bayer digestion condition during the alumina production. The effects of dissolved organic compounds including sodium formate, sodium acetate, sodium oxalate, sodium salicylate and disodium phthalate on the settling performance of goethite slurries were studied. The settling performance of the slurries was also investigated with the addition of self-made hydroxamated polyacrylamide flocculant (HCPAM). The adsorption mechanism of dissolved organic compounds on the goethite surfaces was studied by FT-IR and XPS, respectively. The results show that the addition of organic compounds lowers the settling performance of the slurries and a deterioration in settling performance is observed in the order of sodium oxalate > sodium salicylate (~ disodium phthalate) > sodium formate > sodium acetate. Moreover, HCPAM can efficiently eliminate the negative effects of sodium formate, sodium acetate and sodium oxalate on the settling performance of the goethite slurries, but it can only partially improve the settling performance of the goethite slurries containing sodium salicylate or disodium phthalate. FT-IR and XPS results show that these organic compounds are chemically adsorbed on the goethite surface. 相似文献
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《International Journal of Circuit Theory and Applications》2017,45(10):1329-1348
In this paper, we propose a new approach for the robust design of complementary metal‐oxide‐semiconductor amplifiers based on settling‐time specifications. The approach is based on the definition of the separation factors and on the analysis of their role in the settling time. We define a design strategy for being certain that an OTA satisfies the settling‐time constraint under any statistical variation of process or design parameters. The proposed strategy is applied to the transistor level design of a two‐stage amplifier and a three‐stage one. Simulation results, in good agreement with theory, confirm the validity of the proposed approach. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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The effects of magnetic field intensity, roasting temperature and roasting time on digestion rate and settling performance of bauxite with different iron contents were investigated systematically. The results indicate that such magnetic treatment can profoundly change the microstructure and digestion performance of bauxite. For the two samples carrying different iron contents, phase transformation of the aluminum oxide phase proceeds faster in the high iron bauxite than the low one. The optimal pretreatment conditions of low iron bauxite are roasting temperature 550 ℃ and magnetic field intensity 6 T, while for high iron bauxite are 500 ℃ and 9 T. The digestion rate of alumina can reach 95% and 92% at digestion temperature of 190 ℃ and 250 ℃. The settling performances of roasted ore by intense magnetic field after digestion are enhanced through pretreatment. 相似文献
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Abhinesh Kumar Prajapati Neha Sharma Rakesh Kumar Jena Preena Shrimal Parth Bagtharia Rajesh Kumar Kaushal 《分离科学与技术》2016,51(13):2276-2283
The electrochemical treatment (ECT) of textile wastewater was carried out in a 1.5 dm3 electrolyte batch reactor using iron electrodes. With the four plate configurations, a current density (CD) of 89.2 A/m2 and a pH value of 8.5 were found to be optimal, at which maximum reduction in chemical oxygen demand (COD) and colour achieved were 86% and 79%, respectively. Loss of 0.0666 kg/m3 iron electrode and 18.44 kWh/m3 power consumption was observed during ECT with a maximum COD reduction of 79%. The settling characteristics of electrochemically treated effluents as well as the characteristics of foam and residue were also analysed. 相似文献
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该矿自磨生产线产量低、超细粉含量高、成品率低,急需进行改造。分析可知,经缩短斜管长度、增大沉降箱体尺寸、更换除尘器和主风机等改造后,磨机产量能达14t/h以上(经验值,下同),超细粉含量可降至20%以下,产品产率可由65%提高到80%以上。 相似文献