Advanced Materials Research Vols. 807-809

Abstract: The isotope age distribution and frequency distribution histogram of Jiangnan orogeny were analyzed in this paper. Through measuring U-Pb, Sm-Nd, Rb, Sr, K-Ar, ⁴⁰Ar/³⁹Ar isotope and fission track in sealing temperature, the evolution history in Jiangnan orogeny was divided into four stages. New archean-paleoproterozoic tectonic thermal event, Proterozoic tectonic magmatic event, tectonomagmatic events during Jinning period, and early Paleozoic to Cenozoic tectonic thermal event were happened in 2958~2421 Ma, 2137~1625 Ma, 1379~726 Ma, and 445~45 Ma, respectively. Each construction phase could be divided into the different period of time. There were three long time tectonic thermal halcyon period between the four stages, which suggested that the tectonic movement was intermittent, not persistent in Jiangnan orogeny.

Abstract: The copper oxide ore in Dali, which contains 0.69% of copper and 11.24g/t of silver, was beneficiated by sulphidizing - xanthate flotation method. The flotation tests were carried out systematically with sodium sulfide as sulphidizing agent and butyl xanthate + ammonium dibutyl dithiophosphate as the combined collectors. Through closed-circuit test, a copper concentrate with 18.34% of Cu grade and a recovery of 70.13% were obtained. In addition, silver also was enriched in copper concentration with a grade of 329.37g/t and a recovery of 78.79%, which is convenience for utilization in metallurgical processes.

Abstract: By turning to the elastic thin slab theory, the present authors have established a model for the mechanical assessment of the roof failure for the severely inclined seam under long wall working in swith formulae deduced for the calculation of the stress distribution. When the roof stress distribution is characterized, a model for the roof breakage of the long wall coal seam under working, with failure assessment parameters deduced.

Abstract: Based upon the engineering background of IV315 coal mining face of Mengzhuang Coal Mine, the numerical simulation software UDEC is used to analyze rational packing width under the conditions of different filling widths on the driving roadway. The rational coal pillar size is initially decided as 2.0 meters through simulating and analyzing. On this basis, the influence of second mining on the retaining roadway was analyzed by numerical simulation. Combined with the field measurement, the support parameters and the 2.0 meters packing width are proven to be rational, which provides a reference for the coal mining faces with similar conditions.

Abstract: The water disaster of floor in coal mine is a difficult problem of production and scientific research. Coal mine workers and scientific-technological workers are very concerned about this problem.The pressure-bearing karst water of 5^# limestone poses a threat to production of 8^# coal seam. Combining with the method of water inrush coefficient and Kriging interpolation method analyze the possibility of water inrush. The water inrush coefficient contour map has good convexity, verisimilitude and smoothness. Results accord with actual situation and intuitively reflect the 8^# coal seam floor water inrush risk .The water inrush coefficient in the actual mining area is not more than 0.1 MPa/m, but in the future and in mining regional the water inrush coefficient could be very big, so we need to take the necessary precautions.

Abstract: Base on the fully mechanized coal face of 8113 (1) in LaoYingSan mine, numerical analysis method was applied to analyze the ground pressure feature, FLAC software is carried out to set up numerical model, and offer numerical procedure. The mining abutment pressure distribute form and its partition in front of fully mechanized working face. All four different mining height (2.6m2.8m3.0m3.2m) was respectively calculated. In addition, the influence of mining speed to mining abutment pressure and intervals is analyzed, four different mining distance (20m30m40m50m) selected separately. Afterwards, the different solution analyzed respectively, these results show that the mining abutment pressure distribution form in front of fully mechanized working face essentially identical, they including the stress increasing zones, the stress decreasing zones and the initial rock stress stable field. The influence of mining pace to wall rock looseness range greater than mining height.

Abstract: Taking 24 mining area of Zhouyuanshan mine as the research object, analysis on law of ground subsidence and strata movement caused by backfill mining of "under three" coal is carried on by using numerical simulation method. A three-dimensional numerical model is established by using FLAC 3D software. To analyze the computational scheme of remain wide coal pillar and gradually to finish backfill mining, results showed that the maximal subsidence displacement value is 30.8mm along the coal strike and the subsidence displacement value is 32.1mm along the coal seam inclination; In addition, computational scheme of backfill mining with narrow coal pillar is analyzed, results showed that the filling body plays a stronger supporting role for the roof strata, to fully mobilize the bearing capacity of filling body, forming a relatively coordinated bearing system of " backfill body + coal pillar + overlying strata ".

Abstract: It is difficult to handle platinum-palladium ores in Jinbaoshan due to low grade ores, kinds of mineral resources, complex mineral structure, fine-grained dissemination, which is a typical refractory complex ores. Based on the research of lots of correlative literature, this article analyses refractory reasons of platinum-palladium ores in Jinbaoshan, and provides an overview of comprehensive utilization status of low grade and refractory platinum-palladium ores on behalf of single flotation process, stage grinding-stage sorting and the combined process of flotation and magnetic separation, microwave pretreatment-leaching-replacement process, and the activation of acid leaching-extracting magnesium and iron-leaching residue to flotation process and so on.

Abstract: With regard to a deep-extend oxidized refractory lead-zinc ore from Yunnan province, containing 4.55% Pb and 17.09% Zn, a test study was carried out. By adopting single-stage roughing, single-stage scavenging, two-stage cleaning in the flotation of lead oxide ores, and single-stage cleaning, single-stage cleaning in the reverse flotation of zinc oxide ores, bulk concentrate of lead and zinc containing 36.60% Pb, 19.63% Zn with the Pb recovery of 82.45%, zinc concentrate containing 36.52% Zn, 0.44%Pb with the Zn recovery of 73.18% were obtained in the closed circuit experiment.

Abstract: the paper determines and calculates the parameter of coal temperature distribution rule and oxidation thermal intensity in the stage of low temperature oxidation of radiating heating, builds the mathematic model with 5 key parameters which affect the coal spontaneous combustion, newly defines a probability function to descript the coal spontaneous combustion dangerous degree, then puts forward a quantitative evaluating parameters: the different value of the indicator represents different dangerous area, a fully extinguished zone, a base extinguished zone, a heat dissipation zone and a oxidation of radiating heating zone. The results have a good accordance with the actual observations value.