Advanced Materials Research Vols. 634-638

Abstract: The characteristics of process mineralogy of the some lead-zinc mine were studied with scanning electron microscope, optics microscopes，and x-ray diffraction. The species of lead minerals and zinc minerals and the chemical composition of the minerals were analyzed. The liberations at different grinding finenesses and the particle sizes of the minerals had been also determined. The phase shape of lead and zinc in the ore was also analyzed. The behaviors of various minerals and mineralogical factors affecting the flotation had been explained clearly. The investigation results were favorable to reasonable selection of flotation parameters and would provide theoretical guidance to lead-zinc separation.

Abstract: Mine ventilation system is a repairable system, with the characters of time-varied and randomness. It made us encounter some difficulties when we discussed the system failure evolution process and its operational reliability, as well as when we sought the system reliability parameters developing trends following with ventilation system operation time variation and air adjustment. Firstly, according to the reliability theory, the failure process characteristic values, which affect the ventilation system, were defined. And then, by mean of the analysis of the failure process deterioration of mine ventilation system, the deterioration and its amelioration discriminants are given basing on two parameters’ Weibull process. Finally, on the basis of adaptive neural network technology, the ventilation system failure processes were simulated, the failure process characteristic parameters were determined, and the failure curves were drawn accordingly. The results show that the failure process of the experiment mine ventilation system is a Non-homogeneous Poisson Process; the mean time between failures of the ventilation system is between 160h and 170h; the failure ratio curves present the trends of concave or convex variation when the system failure process deterioration or amelioration.

Abstract: Huize oxidized lead-zinc ore contains 1.53% Pb, 16.67% Zn, and the oxidation rate of lead reaches up to 95.07%, zinc is 85.27%, belongs to high-zinc but low-lead oxidized lead-zinc ore. According to the characters of ore, the technology that lead prior to zinc and desliming in oxidized zinc flotation has been adopted, as well as combined modifiers, ideal performance that grade and recovery of lead concentrate reaching to 51.61% and 62.54% respectively, and zinc concentrate reaching to 38.90% and 70.22% respectively has been obtained.

Abstract: The surface element distribution, valence and relative density of marine sedimentary phosphate ores from Guizhou province were analyzed by X-ray photoelectron spectrometric(XPS). The effect and mechanism of flotation reagents on collophane flotation was discussed. The raise of C content indicates that the collector can be adsorbed on collophane surface. After treatment with Ca2+, the new compound formed on collophane surface is similar to that before the treatment. No Fe and Mg have been observed after treatment with Fe3+ and Mg2+. The reason might be Ferric and magnesium hydroxide and hydroxo complex absorption occurs on the surface. Then, Fe and Mg2+ could consume collector because of the formation of precipitate resulting from chemical reaction. In other words, Fe3+ and Mg2+ are covered with collectors, thus, they can’t be observed by XPS.

Abstract: Uranium is an important fuel for nuclear power, so the mining and milling of uranium is the base for development of nuclear power. Our experiments study is about the supercritical CO2 fluid extraction of uranium in low grade uranium ore, and the influence of aqueous medium, oxidants, chelating agents and other factors on the uranium leaching. In aqueous media, Fe2 (SO4)3 as the oxidants, supercritical CO2 fluid extraction of uranium has the best effect, the uranium leaching rate reaches 90.44%, significantly higher than that of the conventional acid and alkaline leaching. In the process of extraction of uranium in supercritical CO2 fluid, the uranium in uranium ore is first oxidized to hexavalent uranium, and then forms high solubility of uranyl carbonate complexes. Supercritical CO2 fluid is expected to be used in in-situ leaching of uranium mining of the low grade sandstone uranium deposits.

Abstract: In this study, the influences of important factors on zinc oxide flotation are investigated. Dosages of sulphidizing reagent, the pH regulator, the activator and the collector, use of sodium sulfide as the sulphidizing reagent, sodium carbonate as the pH regulator, copper sulfate as the activator and dodecylamine as the collector are essential to the effective recovery of zinc oxide. In the closed circuit experiment, these agents showed promising effect, a zinc concentrate with 15.39% Zn was produced with 76.92% recovery as a result of flotation experiment, and in the tailings with 18.56% Zn content.

Abstract: The primary object of this fundamental research is to reveal new study of Late Jurassic Manketou Obo Formation and Early Cretaceous Manitu Formation, Baiyingaolao Formation, in Huiyin Obo area, East Ujimqin County, Inner Mongolia. Several sets of experiments were carried out to test the validity of three formations’ age, and these forms can be contrasted with Chagannuoer Formation and Bulagehada Formation from “1/250000 Regional Geology Survey in Hesigewula Farm.” As a result of our study, we concluded that further research into the Mesozoic volcanic rocks on the Huiyin Obo is necessary.

Abstract: Duanwang Coal Mine is located at north of Qinshui coalfield in Shanxi province, China, which gently inclined and thick seams have been mined. Authorized production capacity of the coal mine is 1.8Mt/a. With the increase of mining depth, the mine gas emission quantity increased. Karst collapse columns are very developed in the minefield, and the phenomenon of abnormal gas emission always occurred at the coal face and driving gateway around the collapse columns, then the mine became high gassy one from low gassy mine. Using field measurement and theoretical analysis methods, the following conclusion can be drawn. Karst collapse columns have significant influences on gas emission of the coal face and driving gateway. Here are large amount of free form gas into and around the collapse columns, the collapse columns were disclosure while driving gateway, a large amount of the free gas into collapse column would be instantly released, which caused abnormal gas emission at driving gateway, even leading to gas density exceeding limitation by Coal Mine Safety Regulation of China. However, during mining area of the collapse columns, gas emission quantity at coal face was relatively smaller.

Abstract: A craft of concentrated acid-heating reinforced leaching process is investigated for the treatment of a high arsenic pyrite cinder, a common by-product in vitriol industry. The pyrite cinder, containing 57.37% Fe, and 2.78% As, was conducted for the acid leaching process. The results demonstrated that iron concentrate with 60.57% Fe, 0.28% As and 96.23% of iron recovery was obtained under the optimal acid leaching conditions(Sulphuric acid concentration is a mass ratio of 20%, a leaching temperature of 60°C, a liquid-solid ratio of 2:1 and a leaching time of 120 min).This craft can be used to utilize pyrite cinder and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of sulfuric acid residue and extend raw material sourcing for Chinese steel industry.

Abstract: The properties of a lead-zinc ore are investigated by XRD and SEM analysis methods. Results show that the ore assays 1.27 per cent Pb and 1.62 per cent Zn, mainly occurring in the form of sulfide minerals. Through lead and zinc phase analysis, it is known that the distribution of galena reaches 63.78 per cent, and that of sphalerite is up to 77.16 per cent. And the oxidation rates of lead and zinc will become much more serious as the depth of exploitation increases, which is a great trouble that the mine faces with. So how to improve the recovery of mineral beneficiation is an important means to enhance the economical benefits in the mine. Many tests work have been done to develop a new bulk flotation process to enhance the Pb and Zn recovery. Flotation results of the closed circuit test indicate that the Pb and Zn recovery from the new bulk flotation process can be increase by 10 per cent and 2 per cent, respectively, which makes very considerable benefit for the mine.