Applied Mechanics and Materials Vols. 448-453

Abstract: The artificial neural network has been widely used in various field of science and engineering. The artificial neural network has marvelous ability to gain knowledge. In this paper, according to principle of artificial neural network , Model of artificial neural network of rock bolt support of roadway of coal mine has been constructed,Learning system of BP artificial neural network has been trained,it is shown by engineering application that artificial neural network can handle imperfect or incomplete data and it can capture nonlinear and complex relationships among variables of a system. the artificial neural network is emerging as a powerful tool for modeling with the complex system. Method and parameters of rock bolt support of roadway of coal mine can be predicated accurately using artificial neural network, that is of significance and valuable to those subjects of investigation and design of mining engineering

Abstract: Feed angle have a great effect on the flotation efficiency of self-priming centrifugal flotation cell.In order to improve the efficiency of flotation,the effect of feed angle on the flow field in a self-priming centrifugal flotation cell was investigated using STAR CCM+.The distribution law of velocity,pressure,turbulent kinetic energy under different angles was gotten.The turbulent kinetic energy and the pressure difference increased with the feed angle. Result shows that the feed angle acting on the interior flow field is significant and the feed angle of 20º is more conducive to flotation than others.Conclusion can provide a theoretical foundation for improving flotation efficiency and optimizing flotation structure.

Abstract: The surface subsidence resulting from coal mining can lead to terrible land damage, thus studying the distribution of surface subsidence under thick alluvium is of crucial significance.Focusing on the example of Henghe coalmine in Jining, Shandong province, this paperestablished the prediction model for main section and arbitrary points in mining areas based on the probability integration method, by which the size of subsidence, tilt, curvature, horizontal movement and deformation were predicted after the exploitation of coalbeds 2# and 3#. And the result, which is basically consistent with the actual situation, shows that subsidence areais 78 hm2 and the settlement reaches 9987mm. The thick alluvium covered the mining area accountsfor the greater surface subsidence coefficient, subsidence value, horizontal movement coefficient,horizontal movement, subsidence area and smaller deviation of inflection point.

Abstract: Aiming at actual situation of coal mine safety in China, the main problems in coal mine including geological conditions, scientific support and safety investment, shortage of technicians, safety training and education, and supervision laws were respectively analyzed, and the preventive countermeasures such as strengthening research of mechanism and prevention method of coal mine accidents, increasing safety investment, improving safety training and education, closing or integrating unqualified small coal mines, strengthening safety production supervision and perfecting legal system should be adopted to improve safety status of China coal industry.

Abstract: A new method to determine the crushing size for Desulfurization and deashing is introduced. By this method, the proper crushing size of 3mm for the high sulfur coal in this research is obtained. Three cone hydrocyclone is used as the separation equipment for -3mm size fraction. E_p (Probable error) values from three cone hydrocyclone’s performance on different size fractions are discussed and an E_p value of 0.073 was achieved from three cone hydrocyclone’s treatment of 3mm-0.2mm size fraction. A desulfurization and deashing process is designed which leads to a satisfactory desulfurization and deashing result.

Abstract: Based on the analysis and research on the improvement of water inrush coefficient in deep coal mining under safe water pressure, the author pointed out that water inrush coefficient exits some major theoretical defects in calculation and application at present. The paper stated the choice of equations, choosing parameters and some issues in water inrush coefficient. It was pointed out that critical values are the key for the new equation of water inrush coefficient to be popularized and applied.

Abstract: For traditional mineral development issues such as excessive consumption of resources, deterioration of the ecological environment, proposed develops the vein mining industry on the basis of the artery mining industry, forms the positive cycle system, realizes the integrated development of vein mining industry and artery mining industry. The integrated development of artery mining industry and vein mining industry is an open complex system, the traditional scientific methods cannot solve complex system problems, and complexity science method must be used to resolve it. Through complexity analysis of dissipative structure, coordination effect , overall emergence and complex adaptive system (CAS) of artery mining industry and vein mining industry integrated development, proposed the methodology of research artery mining industry and vein mining industry integrated development is the meta-synthesis, has provided a path of sustainable development for the region mining industry.

Abstract: This paper introduced an approach of using diphenylthiocarbazone-chloroform benzene mixed solvent to determine silver content in the ore by extraction colorimetric method. Ammonium chloride-sodium chloride was used for sample melting, and hydrochloric acidic water was adopted to digestion. Then, some parts of the interference elements were separated from it. Silver was dissolved quantitatively out of the ore, and formed complex negative ion of [AgCl-in the liquor. Chloroform-benzene mixed solvent as extraction solvent of diphenylthiocarbazone could improve the stability of diphenylthiocarbazone and silver complex, thus it could raise the accuracy and precision, simplify the operate procedure, and also avoid that phosgene pollute to the environment.

Abstract: Mining is a large-scale and highly complex misalignment system. The progressive damage and disorder development of the rock mass distort as well as the development that the rock mass evolution curve changes from the linear constant speed stage to the distortion stage which is accelerated by misalignment threaten the safety production in mines seriously. Therefore, the research on the rock mass distortion destroys plays an important part in guaranteeing the safety production in mines. This article elaborates the non-linear dynamics branch theory in detail, analyzes the branch phenomenon in slow change and stress-strain of rock mass according to its characteristics and advances the research procedure of the non-linear dynamics branch theory in mining. Moreover, it establishes the dynamic model according to the physical property of system and determines the stability of system using the branch theory.

Abstract: Despite the widespread use of hydrocyclone in the process of potash ore desliming, its accurate design is often difficult because the feed composition is complicated and the viscosity is high in the brine system. In this study, a numerical approach based on computational fluid dynamics (CFD) was performed to describe the flow field. The numerical simulation of flow pattern in hydrocyclones for potash ore desliming was presented. Some basic information concerning the velocity and pressure distribution is given, and the results can be used as the fundamental basis for its design.