Advanced Materials Research Vols. 634-638

Abstract: Two flotation columns replacing traditional flotation machine and vertical agitate mill were successfully used on copper production in Yangla mine. With introducing of these advanced machines, chalcopyrite with fine dissemination size could be absolutely liberated. In addition, the technological process was further optimized. And Cu grade was improved by 3%, the recovery of Cu, Au and Ag were improved by 3% respectively.

Abstract: In general, dry spraying method is using in mine roadway, but the dry spraying method has many disadvantages. The compactness of concrete is not high. Concrete has low strength. Rebound is very big. And there are much dust. So the wet spraying method is necessary. This method can well solve the disadvantages of dry spraying method, and can greatly improve the working environment.

Abstract: This paper discussed the roles of magnetic roasting and the main factors that affect magnetic roasting. Mechanism research of magnetic roasting shows that feed size, roasting temperature, reducing atmosphere and roasting time are the main four factors. Comparison tests of magnetic roasting in a fluidized bed or in a fixed bed have been done. The results show that the appropriate feed size and reducing atmosphere play an important role in roasting. The roasting temperature in a fluidized bed is lower than that in a fixed bed and the roasting time in a fluidized bed is much less than that in a fixed bed. As a result, roasting in a fluidized bed has a higher efficiency of heat and mass transfer than that in a fixed bed.

Abstract: Centrifugal High Gradient Magnetic Separation (CHGMS) was creatively developed, and in the present investigation was used for the concentration of fine ilmenite from tailings through a cyclic pilot-scale CHGMS separator, to study the effect of two key parameters, i.e., magnetic induction and rotation speed of matrix, on the separation performance of the separator. The results of investigation indicates that the CHGMS is effective in concentrating the ilmenite; an increase in the rotation speed increases concentrate grade but reduces recovery of TiO2, and this is reverse for the induction. While the two parameters were optimized, a concentrate assaying 19.42% TiO2 with 80.72% recovery of TiO2 is achievable from the tailings assaying 8.18% TiO2. It was concluded that the CHGMS provides a prospective technology for the concentration of fine ilmenite.

Abstract: A high Mg phosphate tailings comprehensive utilization research is essentially leaching to remove the magnesium and phosphorus in it and eventually made containing magnesium and phosphorus or other nutrients compound fertilizer. Phosphate tailings utilization in China were introduced, focused on a high Mg phosphate tailings chemistry, phase composition and reaction characteristics and kinetics of the dissolution results. High Mg phosphate tailings comprehensive utilization to achieve industrialization needs more extensive and deeper researches.

Abstract: When cutting rocks using mechanical excavators, the depth of cut (DOC) of cutting picks is a major factor that affects the forces on the picks and the drum on which the picks are installed. To optimize the design of the picks and the drum, as well as the operation of the continuous mining machine, it is necessary to analyze the DOC of individual picks accurately. In a cutting cycle, different picks can be in various positions and consequently have diverse DOCs which are termed the instant DOCs at the corresponding positions. In this study, it is aimed to investigate both accurate solution and approximate formula for the calculation of instant DOC. Based on theoretical analysis, the equations for the calculation of instant DOC have been developed, and the quantitative comparisons between the different DOC calculation methods have been made. The influence of the advance speed per revolution of the drum on the instant DOC, the cut interactions between picks and the cutting sections of individual picks have also been investigated. The results can assist in the selection of an appropriate DOC calculation method and improvement of drum design and operation.

Abstract: Fly ash, which is nominally solid wastes generated during the combustion of coal, contains plenty of valuable minerals. Thus, comprehensive recovery of these valuable minerals not only solves environmental pollution problems but also realizes secondary utilization and added values increase of fly ash resources. The Joint process flow of flotation and magnetic separation was adopted in the experiments to recover carbon and iron from fly ash comprehensively, and good technical indexes had been obtained. Flotation separation was conducted on a sort of fly ash whose ignition loss was about 17%. And the ignition loss of concentrates and tailings obtained are above 55% and below 5%, respectively, which can be for further use. Based on the relatively high contents of iron in flotation tailings, magnetic separation for iron enrichment was carried on subsequently. After concentration, the content of Fe₂O₃ in iron concentrate is above 60%.

Abstract: We used the iron tailings with different concentrations of raw slurry and the classifier overflow after desliming for natural sedimentation and adding flocculants flocculating sedimentation test research. The results show that: the settling velocity is slower during the natural sedimentation, The effect that concentration on the settling velocity of material is larger, with the increase of concentration, particle settling velocity drop, When the concentration reached 20%, material group is in a state of suspension, particle is essentially not settlement; Adding polyacrylamide flocculant for the pulp material pretreatment, the settling velocity is obviously improved than natural sedimentation, Supernatant turbidity also decreased significantly, but the pulp concentration still has a great influence on the sedimentation rate, the higher the concentration of the settlement, the slower settling velocity. The test result is according to the theoretical formula of settlement.

Abstract: A representative Pb-Zn-CaF2 ore sample subjected to this experimental study was taken from Niujie lead-zinc complex, Honghe municipality, Yunnan province, China. The ore sample assays 2.49% Pb, 1.05% Zn, 43.20% CaF2 and 136g/t Ag. In this paper, process mineralogy, Pb-Zn minerals separation and fluorite flotation were investigated, and the optimum reagent dosages for the differential flotation were determined. Three concentrates can be obtained, i.e., the lead and zinc concentrates containing 71.10% Pb (3389.65g/t Ag) and 50.06% Zn (301.23g/t Ag) at the recoveries of 89.02% and 84.20%, respectively; and a fluorite concentrate assaying 97.22% CaF2 with 93.76% recovery. Total Ag recovery in lead and zinc concentrates is as high as 91.55%.

Abstract: This paper researched the effect of six surfactant including aodium dodecyl benzene sulfonate(SDBS)、cetyltrimethyl ammonium bromide(CTAB)、po1yoxyethylene octylphenol ether (OP-10)、Triton X-100(TX-100)、FSO and their mixture on surface tension of the leaching solution and on leaching rate of uranium in sandstone uranium ores. Results showed that all kinds of surfactant could observably reduce the surface tension of the leaching solution at low concentration. The surface tension of leaching solution containing 1g/L FSO and 0.01g/L mixture surfactant(mOP-10 /mFSO; 7:3) was 20.7mN/m and 17.9 mN/m respectively. Results of agitation leach experiments showed that FSO and the system of OP-10 and FSO could improve the leaching rate, and the leaching rate of uranium could be increased by 14.16% and 16.08% to 92.54% and 94.09% respectively. These results indicated that the way of reducing the surface tension of the leaching solution could improve the leaching rate of uranium.