Papers by Keyword: Fluorite

Abstract: Chemical co-precipitation method was used to prepare Gd₂Zr₂O₇ powders. The powders were then heated in air at 1500°C, 1510°C, 1525°C, 1530°C, 1550°C, 1575°C, 1600°C for 5 h, and 1575°C, 1600°C for 10 h, respectively. The samples after heat treatment were characterized by X-ray diffraction and Raman spectroscopy. X-ray diffraction patterns reveal that order-disorder transition of Gd₂Zr₂O₇ occurs between 1550°C and 1575°C. Prior to the transition, the relative intensity of peaks corresponding to the super-lattice of pyrochlores increases with the increasing temperature. On the other hand, Raman spectra give an inconsistent result from the X-ray diffraction data. No appreciable difference can be observed for all the samples though with peaks broadening as temperature increases. The spectra of the samples indicated as fluorite structure in X-ray diffraction patterns appear with six resolvable peaks which is quite different from the spectrum of ideal fluorite structure.

Abstract: Based on the analysis of the ingredient of fluorite from Shandong, a series tests on flotation were carried out. Grinding fineness, modifier picking and collector dosage were researched. Grinding fineness as 70%, forint as modifier and collector dosage as 800g/t, at this condition, a good indicator beneficiation process was made, a fine quality fluorite concentrate was obtained with the grade of 97% and comprehensive recovery of 82.35%.

Abstract: The ore using in this paper was obtained from Hunan Province, China, which contains fluorite (15.65%), barite (48.42%), quartz (30.56%), sphalerite (0.57%), galena (0.54%) and other minerals. After fluorite-barite mixed flotation, fluorite-barite separation flotation, and anti-flotation of lead and zinc minerals, the fluorite concentrate with 97.35% CaF₂ and barite concentrate with 95.49% BaSO₄ was gotten. The recovery of the fluorite concentrate was 81.85% and the recovery, specific gravity, whiteness of the barite concentrate was 95.00%, 4.34g/cm³, 90.65%, respectively. This symbiotic ore can be comprehensive utilized by this beneficiation procedure.

Abstract: Separating fluorite from quartz and calcite by forth flotation can be both in weak-acidized (pH 6.0) condition and weak alkali (pH 9.0) condition. The experiment results have shown that ZnSO₄ can decrease the depression that water glass works on the fluorite, and acidized water glass has a selective inhibition on the silicate minerals. The close flowsheet protocolled in the experiment can obtain the content of CaF₂, SiO₂ in the final concentrate are 97.89%, 0.91% respectively, and the recovery rate of CaF₂ is 84.18%, which is reach the requirement of the plant.

Abstract: Recently, the natural mineral resources became short. In the process of fluorite floatation and tailing recycling, the key point is to find out collectors which have good selectivity to fluorite and effective inhibitor of gangue. Most reagents primarily come from agricultural byproduct and some chemical byproduct. However, the tailing mineral is complex and difficult to collect, which brought out accumulation of tailing mineral and water polluted. We try to modify the fluorite collector by use of computer-aided design drawing software and molecular mechanics curve between reagents and useful components in mineral and screen the best reagent. Interaction energy between drugs and fluorite surface is simulated and calculated by molecular mechanics at the atomic level. To determine that the interaction energy between collector and mineral simulated and calculated by molecular mechanics is helpful for demonstrating interaction mechanism. Finally, the better use of tailing mineral is good for environment pollution.

Abstract: Beneficiation of a Pb-Zn tailings containing 44.98% CaF2 was conducted by flotation using sodium hexametaphosphate and new reagents S180. Details of reagent consumption, adding reagents at different stages and concentration of flotation pulp were investigated. Through all the investigation, an optimum reagent system and flowsheet were established. Finally, a marketable fluorite concentrate assaying 98.32% CaF2 with the recovery of 95.00% was obtained by one rougher,6 cleaners and 2 scavengers.

Abstract: The grade of the low quality fluorite ore was assayed around 30.95％CaF₂. When the grain size achieved by 65% of -200 mesh at the first stage grindings and the grain size achieved by 100% of -400 mesh at the second stage grindings, the circuit of one rough floatation and six cleaning floatation are used in the recovery of fluorspar, the result is obtained that the fluorite concentrate grade of CaF₂ is 98.50%,with the recovery of 54.10%.

Abstract: The run-of-mine ore samples which have been used in the study were taken from a fluorite ore. The grade of fluorite was 28.65%. From the condition test, the optimal grinding fineness was-0.074mm accounted for 79.5%. The final optimal reagent system was A₁B₃C₃D₃E₃ with comprehensive consideration. That is, sodium carbonate was 2000 g/t, sodium silicate was 1000 g/t, aluminum sulfate was 200 g/t, sodium hexametaphosphate usage was 1000 g/t, oleic acid dosage for 2000 g/t. Through the closed-circuit test of flotation, the final index was the fluorite grade of the concentrate was 97.69% and the recovery was 48.07%.

Abstract: The present authors have utilized, for the first time, H₃BO₃ as an additive in pilot scale experiments of Mg production using Pidgeon process. The results from the experiments revealed positive effects of H₃BO₃ on both quantity and quality of the Mg metal crowns. Besides acting as a catalyzer for MgO reduction, H₃BO₃ stabilized also β-Ca₂SiO₄ in the Mg slag. Based on these results, H₃BO₃ may be adopted as an innovative additive replacing fluorite in the Mg production, to enhance sustainability and environmental soundness for the Pidgeon process in China.

Abstract: Grade of fluorite in this test is 30.95%,containing CaCO3 0.86%. On the base of much experiment research, such as grinding fineness test, pH test, agent dosage test and so on, the optimum conditions were: grinding fineness for first stage is -0.074mm 65%,pH=9, sodium silicate 0.8 kg/t and oleic acid 0.7 kg/t . The result of tests showed that the grade of CaF2 concentrate, recovery and productivity are 95.38%, 63.42% and31.20% by adopting a circuit of one rough flotation and seven concentrating with grinding fineness -0.043mm90.3%.