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Zuo W.,Hebei United University | Xu Y.,Hebei United University | Wang Y.,Hebei United University | Li M.,Hebei United University | Li M.,Hebei Iron and Steel Group Mining Co.
Lizi Jiaohuan Yu Xifu/Ion Exchange and Adsorption | Year: 2013

A series of hyperflltration experiments were conducted to investigate clay membrane behavior and filter salt effect about natural cohesive soil. Soil samples were collected from 30m deep aquitard of Luanhe River alluvial fan, and particle composition, pore characteristics and clay mineral content of the undisturbed soil sample were tested. Soil columns were backfilled according to the natural porosity ratio of the undisturbed soil samples. After saturation, the constant head penetration experiments were conducted with brine. Monitoring results showed that infiltration solution continuously enriched seepage discharge constantly decreased. At the end of the experiments, the ratio of the Cl- concentration of the outflow liquid and of the inflow solution was 1.1, and in addition concentration growth of Na+ was significantly lower than that of Cl-. The Cl- concentration of infiltration solution by theoretically calculated was close to the measured concentration at the state of the steady flow. The experimental results of the infiltration solution concentration and the concentration polarization phenomenon of the clay layer surface indicated that the clay had certain membrane properties. The efficiency coefficient σ of clay membrane was negatively correlated with concentration of ions and degree of soil consolidation, and was positively with degree of soil consolidation degree and the ion exchange adsorption ability of the soil. Although the natural cohesive soil had membrane properties and could concentrate the solution at the side of high pressure, it couldn't play a role of restricting completely salt as reverse osmosis membrane.

Li X.,University of Science and Technology Beijing | Gao Q.,University of Science and Technology Beijing | Liu Z.H.,University of Science and Technology Beijing | Nan S.Q.,Hebei Iron and Steel Group Mining Co.
Rock Mechanics: Achievements and Ambitions - Proceedings of the 2nd ISRM International Young Scholars' Symposium on Rock Mechanics | Year: 2012

According to the force characteristics of cemented backfill, the cemented backfill stability mechanical model under tailings was established. According to the cemented backfill stress boundary conditions of south section -450 m of Sijiaying iron mining, the maximum lateral stress of cement backfill from tailings is 0.37 Mpa, the maximum shear stress reaches to 1.1 Mpa in the middle of backfill by the side of the tailings; the overturning safety coefficient of cemented backfill under tailings backfill is 1.13; the safety coefficient of the backfill compressive strength is 1.05; the upright safety coefficient of cemented backfill is 3.07. At the same time, the results of physical simulation experiment showed that the overturning of backfill, compressive strength and upright strength under the ratio 1:10 of cemented backfill can basically satisfy the requirements, but pieces of backfills were observed to be failed down on the top surface, which produced a security risk. So, it is necessary to improve the backfill strength. © 2012 Taylor & Francis Group.

Li X.,University of Science and Technology Beijing | Gao Q.,University of Science and Technology Beijing | Zhai S.H.,University of Science and Technology Beijing | Nan S.Q.,Hebei Iron and Steel Group Mining Co.
Rock Mechanics: Achievements and Ambitions - Proceedings of the 2nd ISRM International Young Scholars' Symposium on Rock Mechanics | Year: 2012

According to the phases-subsequent filling method in large iron ore of southern district Sijiaying, the current conditions of ore body and requirement of mining are analyzed in detail. By taking into account of factors such as protection of water resources and environmental, control of rock movement, efficient and large-scale mining, deceasing of losses and dilution, the stope structure optimization is carried out. After analysis on the main factors of economy and security, the value range and constraint conditions are defined, and a series of three-dimensional numerical analysis are performed. By regression analysis, the functional relationship between mining safety-rock movement parameters and the design parameters are achieved. By solving the optimization model, the optimization structural parameters of the stope are obtained. © 2012 Taylor & Francis Group.

Wenli J.,Wuhan University of Technology | Wenli J.,Hebei Iron and Steel Group Mining Co. | Yimin Z.,Wuhan University of Technology
IMPC 2014 - 27th International Mineral Processing Congress | Year: 2014

In order to enhance the quality of iron concentrate from magnetic separation, reverse-flotation technology is often applied in an iron ore dressing plant. However, this technology has disadvantages in terms of operating cost, energy consumption and environmental protection (Zhao, Wu & Wang, 2005). Developing innovative equipment to process magnetite ore more-effectively is a way to get rid of these disadvantages of reverse flotation and improve the quality of iron concentrate. This paper describes the development of Complex Flashing-Field Magnetic Cleaner, a new kind of equipment based on the principle of combination of separation in magnetic field and separation in gravity field (Hao & Jiang, 2002). This innovative equipment possesses a tailor-made magnetic system and has the characteristics of a magnetic field which can strengthen the formation of magnetic agglomerations and the dispersion of gangue minerals to improve the quality of separation. The automatic control system developed specifically for this equipment can further increase the accuracy of separation and stabilize the process.

Li M.-Y.,Northeastern University China | Wei D.-Z.,Northeastern University China | Shen Y.-B.,Northeastern University China | Liu W.-G.,Northeastern University China | And 3 more authors.
Transactions of Nonferrous Metals Society of China (English Edition) | Year: 2015

2,3-disulfanylbutanedioic acid (DMSA) was found to be a selective depressant in the flotation separation of copper- molybdenum sulfides. The flotation results suggest that a low dosage of DMSA has a strong depression effect on chalcopyrite in the pH range between 4 and 12. At pH 6, the recoveries of molybdenum are up to 85%, 75%, and 80% while those of chalcopyrite are 15%, 5%, and 20% respectively when flotation tests are carried out with single minerals, mixed minerals and molybdenum-bearing copper concentrates. Adsorption isotherms measurement indicates that DMSA adsorbs more strongly on chalcopyrite than on molybdenite. The frontier orbital calculation reveals that the two S atoms of DMSA molecule are active centers for the adsorption of the DMSA molecule on chalcopyrite surface. Fermi level calculation shows that chalcopyrite can obtain electrons from the DMSA molecule while molybdenite cannot. © 2015 The Nonferrous Metals Society of China.

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