Orthogonal Experimental Research the Gangue in Gallium Extraction Conditions
Tian Aijie,
Tian Aimin,
Kong Lingliang,
Liu Zhenxue
Issue:
Volume 5, Issue 3, September 2020
Pages:
37-41
Received:
6 August 2020
Accepted:
21 August 2020
Published:
27 August 2020
Abstract: After mining for many years, the coal gangue piles up, not only occupies a large amount of land, but also causes serious pollution. Therefore, the treatment and utilization of coal gangue has become an important topic for coal mining and environmental protection departments. The inorganic components of coal gangue are mainly SiO2 and Al2O3, followed by Fe2O3, generally accounting for 75%~80% of all components. Organic components are mainly composed of Carbon, Hydrogen, Oxygen, Nitrogen and organic Sulfur, accounting for 20%~25% of all components of oal gangue. In addition, the gangue also contains a small amount of Gallium, Alum, Germanium and other rare earth elements. In recent years, the research of extracting Gallium from other raw materials has developed rapidly. In order to make full use of the waste of resources, turning waste into treasure, improve the economic and social benefits, the paper adopted orthogonal experiment to explore the the gangue gallium extraction conditions. The experiments take the high-temperature acid leaching method of orthogonal experimental design experimental conditions. Acid concentration, ignition temperature, ignition time, the acid leaching temperature, leaching time and other factors on the extraction rate of gallium. After a large number of scientific comparison of the experimental conditions, to get the better conditions of the extraction of gallium that acid concentration 6mol / L, the ignition temperature of 600°C, the ignition time 0.5h, acid leaching temperature of 100°C, leaching time for 6 h. The extraction rate of 95%, provide a viable experimental conditions for the gangue gallium extraction.
Abstract: After mining for many years, the coal gangue piles up, not only occupies a large amount of land, but also causes serious pollution. Therefore, the treatment and utilization of coal gangue has become an important topic for coal mining and environmental protection departments. The inorganic components of coal gangue are mainly SiO2 and Al2O3, followe...
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Enhancing Performance of Silty Clayey Sandy and of Pavement Using Cement and Geogrid in South Republic of Benin (West Africa)
Alaye Quirin Engelbert Ayeditan,
Agbadogbe Senan Jeannot,
Toure Youssouf,
Chango Valere Loic,
Assogba Ogoubi Cyriaque
Issue:
Volume 5, Issue 3, September 2020
Pages:
42-53
Received:
15 September 2020
Accepted:
15 October 2020
Published:
26 October 2020
Abstract: Pavement infrastructure built on expansive soil can experience multiple forms of degradation, mainly cracks when there are no adequate arrangements made to avoid or to limit the impact of the changes on the volume of the supporting soil. In this research, three objectives have been adopted in-depth on the performance characteristics of West Africans soil and aim to (i) accessing characteristics of soil types in the region; (ii) assessing the performance of these soils with 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5% and 5.5% of cement and (iii) using geogrid to evaluate the performance of pavement on clayey soil. Design of flexible pavement is largely based on empirical methods using layered elastic and twodimensional finite element (FE) analysis. Currently a shift underway towards more mechanistic design techniques to minimize the limitations in determining stress, strain and displacement in pavement analysis. For this reason, computational analysis of pavement methods have been investigated on the structural model pavement and the effectiveness of geogrids as a reinforcement of layer in a flexible pavement system. In this study, flexible pavement modeling is done using Abaqus software in which model dimensions, element types and meshing strategies are taken by successive trial and error to achieve desired accuracy and convergence of the research. Flexible pavements (with and without geogrids) were built and subjected to 127.49 kN load applications and the Finite Element Method (FEM) as computer analysis under static load. The results reveal that the proportion of percentage cement leading to the best performances varying from 3% to 5.5%. And, the pavement made with geogrid in subgrade is the best. As a conclusion, in an unstable area, this research suggests the use of silty clayey sandy treated with a minimum percentage of 3% cement in subbase layer and geogrid in subgrade because, the inclusion of geogrid in subgrade reduces the deformation.
Abstract: Pavement infrastructure built on expansive soil can experience multiple forms of degradation, mainly cracks when there are no adequate arrangements made to avoid or to limit the impact of the changes on the volume of the supporting soil. In this research, three objectives have been adopted in-depth on the performance characteristics of West African...
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