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51.
Flotation has been used in industry for more than a half century as the primary technique for upgrading phosphate. While the flotation of phosphate was inefficient when oleic acid was used alone as a collector, therefore a mixed collector of oleic acid (HOl), linoleic acid (LA) and linolenic acid (LNA) was employed to improve the recovery of phosphate flotation. The batch flotation results showed that the optimal composition of the mixed collector was 54 wt.% HOl, 36 wt.% LA and 10 wt.% LNA. Additionally, the effect of pH on the mixed collector application was studied while considering the surface tension, contact angle and micro-flotation. The results showed that the mixed collector should be used at a pH of 9.5. Above a pH of 9.5, the adsorption of fatty acids dimers on the apatite surface hindered phosphate flotation. The influence of the mixed collector assembly on apatite flotation was also investigated. It was demonstrated that due to its low critical micelle concentration, a sufficiently hydrophobic apatite surface could be generated at a collector concentration of 60 mg/L. In addition, zeta potential experiments suggested that collector adsorption was governed by chemisorption. FTIR and XPS spectra studies further indicated that the chemical reaction involved the carboxyl groups of fatty acids and Ca species at the apatite surface for each fatty acid in the mixed collector. 相似文献
52.
王小生 《有色金属(选矿部分)》2019,(1):35-38
柿竹园野鸡尾铜锡多金属矿含Cu 0. 18%,含Sn 0. 36%,其它有价元素均较低。由于铜锡有价元素嵌布粒度较细,磨矿粒度较细,采用重选回收率较低,因此采用浮选的方法来回收锡石。本研究采用碳酸钠作为pH值调整剂,硝酸铅作为活化剂,GYB作为捕收剂,松醇油作为起泡剂,采用一次粗选两次扫选三次精选的工艺流程,最终闭路试验结果表明,锡石精矿中锡含量为5. 27%、回收率62. 42%。 相似文献
53.
Guangda Li Kaili Zhang Zhengjun Pei Nan Zhang Yaozhi Yu Santuan Zhao Gaofeng Liang Jing Zhou Yuying Xing 《Ceramics International》2019,45(4):4945-4956
In this study, a novel method was proposed to enhance the magnetic property of magnetic bioactive glass-ceramic (MBGC) using graphite-modified magnetite. The crystalline composition, chemical structure, in vitro bioactivity, magnetic property, heat generating ability, cytotoxicity and the hyperthermia treatment effectiveness of the synthesized material were investigated thoroughly. The results revealed that the addition of graphite could prevent the magnetite from being oxidized. The main phases of the as-prepared material were found to be Fe3O4, Ca2.87Fe0.13(SiO3)3 and Ca2SiO4 in the CaO-SiO2-MgO-CaF2-P2O5-Fe3O4 system. Moreover, the material was bioactive and hydroxyapatite was observed on the surface after soaking in simulated body fluid (SBF) for 10 d. Under a magnetic field of 1.6?×?106 A?m?1, the saturation magnetization of MGBC was about 10.6?A?m2 Kg?1, while that of the contrast sample was only 2.9?A?m2 kg?1. When exposed to an alternating magnetic field (252?kHz, 1.9?×?103 A?m?1) for about 20?s, a temperature rise of 20?°C could be observed on the sample surface. MTT assay results showed that the material had no cytotoxicity for VX2 cells. Moreover, the hyperthermia treatment experiments were carried out by exposing the block samples (Φ8?×?2?mm) and VX2 cells simultaneously to the alternating magnetic field for 20?min. Only about 30% cells survived after the treatment, and dead cells were observed around the material. Therefore, this novel material could have potential applications for clinical hyperthermia treatment. 相似文献
54.
C. R. Copeland S. K. Kawatra 《Mineral Processing and Extractive Metallurgy Review》2019,40(3):218-223
Both straight-grate and grate-kiln furnaces have been accepted in the iron ore industry. Both are considered to be roughly equal when comparing overall costs and expenses versus the final product production rate. However, the product quality of these two systems is not equal. This is shown by critically examining the dust generation of pellets from several facilities. The dustiness of pellets is associated with overall pellet strength, and is an important quality measure of fired pellets on its own. A clear distinction between the dustiness of grate-kiln and straight-grate fired pellets is established. We conclude that grate-kiln-cooler systems provide superior pellet quality, but at the cost of some pellet production rate. 相似文献
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57.
通过河南省渑池地区含锂铝土矿(岩)层工艺矿物学分析,查明铝土矿的物质组成、嵌布特征、伴生锂分布特征和赋存状态,为矿产综合利用提供理论依据。结果显示:该铝土矿Al2O3含量为54.8%,铝硅比值(A/S)为2.6,铝土矿层和粘土岩层中Li2O含量均高于伴生锂边界品位,粘土岩中锂更为富集;矿物组成除一水硬铝石之外,主要是以集合体形态产出的粘土矿物。采用稀酸解析、选矿测试和电子探针分析锂的赋存状态,查明矿石中锂主要是以类质同象置换形式赋存在伊利石和高岭石等粘土矿物中;选矿富锂尾矿中Li2O可富集到0.57%左右,是锂综合回收利用的重点研究对象。 相似文献
58.
某铜矿重介质产品铁品位56.24%,硫含量高达9.34%,95.72%的硫以磁黄铁矿的形式存在。为获得硫含量<2%的铁精矿,按磨矿—弱磁选—浮选原则流程对该矿石进行了选矿试验。试验结果表明,在最佳试验参数下,重介质产品经一段磨矿(-0.043 mm 85%)—1粗1精弱磁选—1粗2扫脱硫浮选流程处理,可获得产率45.23%、硫含量为1.52%、全铁品位66.50%的铁精矿,可作为后续钢铁冶炼原料的配矿使用,为此类重介质产品的利用提供技术参考。 相似文献
59.
针对某铜镍矿铜镍品位低,铜镍矿物嵌布粒度微细,共生关系复杂,蛇纹石含量高等特征,开展了选矿工艺试验研究。试验结果表明,采用预先脱除脉石-铜镍混合浮选流程,通过对含Ni 0.51%、含Cu 0.20%、含Co 0.02%的原矿进行选择性磨矿,利用MIBC预先脱除部分易浮脉石,碳酸钠作矿浆pH调整剂,CMC作MgO脉石的抑制剂,硫酸铜和丁基黄药分别作铜镍矿物的活化剂和捕收剂,全流程浮选闭路试验获得了含Ni 7.78%、Cu 2.91%、Co 0.24%,回收率分别为Ni 72.98%、Cu 66.57%、Co 51.29%的铜镍混合精矿。该工艺流程获得了较好的选别效果,实现了铜、镍、钴的有效回收。 相似文献
60.
针对国内某选矿厂铜浮选工艺泡沫速率不稳定,精矿品位波动大,回收率不理想等特点,设计了一套浮选专家控制系统,该系统结合泡沫影像分析技术,在线品位分析技术,PID控制与模糊逻辑控制技术。系统架构简明合理,逻辑层次清晰有效,投入运行一段时间后,在不同原矿品位前提下,都能实现稳定泡沫速率,减少精矿品位波动,提高回收率等指标优化,同时药剂添加量也有明显减少。这表明该系统运行效果良好,值得应用推广。 相似文献