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91.
湖北省宜昌硅钙质沉积磷块岩,是难选的中低品位沉积磷块岩,主要磷酸盐矿物为泥晶磷灰石,主要脉石矿物为白云石、石英、玉髓.从获得高品位精矿、高回收率选矿工艺指标的角度,对含泥量较高的中低品位硅钙质沉积磷块岩,进行选矿工艺研究。确定分级-反浮选（常温）最佳选矿工艺路线为：选矿技术指标为磨矿细度-0．074mm（-200目）,含量占67．7％,原矿品位P2O5 25．89％,精矿产率58．61％、品位P2O5 35．22％,回收率80．00％.通过工艺流程试验研究的论述,旨在向年轻的选矿工作者传达一种工作思路,同时对于选别同类型磷矿的矿山企业也有一定的参考价值、 相似文献
92.
93.
There have been a couple of contaminant retardation factors reported for the three-phase (aqueous, solid, and colloid) groundwater system. However, the retardation factor has often been presented by itself and not incorporated into the relevant transport equation, particularly when derived from the mass fraction approach. This may cause a misunderstanding of the retardation factor especially for the systems where multi-phases exist due to the presence of colloids and/or nonlinear sorption processes are involved. It is, therefore, necessary to clarify the form of the nonlinear retardation factor along with the relevant transport equation in the multi-phase system. Alternative forms of the retardation factor and relevant transport equation for specific conditions are presented in various combinations of the nonlinearity of involved sorption mechanisms. The retardation factors for specific conditions are compared with the ones available in the literature. The results indicate that more caution should be given in applying the retardation factor in order to explore contaminant transport in the multi-phase system where any nonlinear sorption is involved. Finally, presentation of the retardation factor along with the relevant transport equation in this study would help prevent possible misuse of the retardation factor in investigating contaminant transport in the multi-phase system. 相似文献
94.
95.
T.N. Khmeleva J.K. ChapeletW.M. Skinner D.A. Beattie 《International Journal of Mineral Processing》2006
The effect of sodium bisulphite on the xanthate-induced flotation of copper-activated sphalerite has been studied using batch flotation testing, surface analysis techniques (XPS and ToF-SIMS), and FTIR. The various techniques have been used to identify the mechanisms of interaction of sulphite ions with both collector and the sphalerite surface. The results indicate that sodium bisulphite depressed the flotation of sphalerite particles pre-treated with copper and xanthate at pH 9 with nitrogen and air purging. It was found that sodium bisulphite interacts with the sphalerite surface, as well as with xanthate in its adsorbed state. Based on the evidence obtained in the present study, and in conjunction with previous work, the mechanisms involved in the depression of the xanthate-induced flotation of copper-activated sphalerite by sulphite are proposed. It is suggested that copper xanthate decomposition on the surface of the activated sphalerite and the decomposition of the hydrophobic copper-sulphide-like species on the sphalerite surface are the active mechanisms for sphalerite depression by sodium bisulphite. 相似文献
96.
A series of N-arylhydroxamic acids (31) were synthesized and tested as collectors to float sphalerite from a Canadian copper–zinc ore. The compounds were classified into four types namely, N-aryl-C-alkyl, N-aryl-C-aryl, N-aryl-C-aralkyl, and dihydroxamic acids based on the type of substitution. Dihydroxamic acids were found to be poor mineral collectors while the efficiency of sphalerite flotation increased in the order N-aryl-C-aryl < N-aryl-C-alkyl < N-aryl-C-aralkyl. Sphalerite was floated without activation by copper sulfate, and the best sphalerite recovery of about 80% (grade 32%) was achieved with N-hydrocinnamoyl-N-phenylhydroxylamine (HCNPHA) 67 g/t collector dosage. However, pyrite also floated along with sphalerite and this appeared as a major disadvantage to be addressed. 相似文献
97.
Luis A. Cisternas David A. Méndez Edelmira D. Gálvez Rodrigo E. Jorquera 《International Journal of Mineral Processing》2006
A method for the design of flotation circuits is presented. The design problem is represented by several superstructures. The first superstructure represents separation tasks (STS), which include: feed processing superstructure (FPS), concentrate processing superstructure (CPS), and tail processing superstructure (TPS). The FPS commonly uses a single stage, i.e., rougher. The CPS represents the circuit needed to carry out the cleaner task, and the TPS represents the circuit needed to carry out the scavenger task. These superstructures are flow networks between several separation stages. In each separation stage two kinds of cells are allowed, bank and column. In several streams in the CPS and TPS, the incorporation of regrind mills is also included. 相似文献
98.
Spherical calcium dioleate particles (∼ 10 μm in diameter) were used as AFM (atomic force microscope) probes to measure interaction forces of the collector colloid with calcite and fluorite surfaces. The attractive AFM force between the calcium dioleate sphere and the fluorite surface is strong and has a longer range than the DLVO (Derjaguin–Landau–Verwey–Overbeek) prediction. The repulsive AFM force between the calcium dioleate sphere and the fluorite surface does not agree with the DLVO prediction. Consideration of non-DLVO forces, including the attractive hydrophobic force, was necessary to explain the experimental results. The non-DLVO interactions considered were justified by the different interfacial water structures at fluorite– and calcite–water interfaces as revealed by the numerical computation experiments using molecular dynamics simulation. The density of interfacial water at the fluorite surface is low and the fluorite surface is not strongly wetted by water molecules. In contrast to the water at the fluorite surface, water molecules at the calcite surface form tightly packed monolayer structures and the calcite surface is extensively hydrated by water molecules. The interfacial water structure agrees with the AFM force measurements and the flotation recovery data. The strong attraction between the calcium dioleate colloid and the fluorite surface, and the moderately wetted fluorite surface by water molecules explain the better flotation response of fluorite with the oleate collector colloid. 相似文献
99.
100.