A study of the effects of the pulp nature on desulphurization and de-ashing during high-sulfur coal flotation is described in this paper. Highlighted are the use of a solution oxygen gauge, a pH value gauge and a surf...A study of the effects of the pulp nature on desulphurization and de-ashing during high-sulfur coal flotation is described in this paper. Highlighted are the use of a solution oxygen gauge, a pH value gauge and a surface tension gauge to investigate changes in the pulp nature related to changes in the oxygen content, the pH value and the interfacial tension. The temperature be- fore and after ultrasonic conditioning was also investigated. The results showed that ultrasonic conditioning resulted in a decrease in the oxygen content and the interracial tension and an increase in the pH value and the temperature of the pulp. The perfect index of flotation and the perfect index of desulphurization of fine coal increased by 25.19% and 18.03%, respectively, after the pulp was ultrasonically conditioned. This study shows that ultrasonic conditioning can change the pulp nature and enhance the degree of desulphurization during high-sulfur coal flotation.展开更多
A novel vacuum ice slurry producing system with jet-pumps was proposed to deal with the problems of high energy consumption and ice blockage.In this novel system,one steam driven by a jet-pump was used to create vacuu...A novel vacuum ice slurry producing system with jet-pumps was proposed to deal with the problems of high energy consumption and ice blockage.In this novel system,one steam driven by a jet-pump was used to create vacuum in a hermetic vessel where water was sprayed through a nozzle to produce ice slurry,while the other steam was used to provide enough cold energy to make the left vapor in the hermetic vessel condense.Mathematical models of this novel system were established and theoretical simulation on the performance characteristics was also implemented based on the MATLAB program.Results show that the novel system is feasible and practicable,and the system performance is affected by many factors,such as the temperature of the generators,condensing temperature,evaporation temperature,and the cooling load of the refrigerator sub-system.The findings are helpful to improve the performance of ice slurry producing system.展开更多
In recent years, the need for low energy materials has become increasingly important. With government targets aiming to reduce carbon emissions by 80% by 2050, and the construction industry being responsible for 50% o...In recent years, the need for low energy materials has become increasingly important. With government targets aiming to reduce carbon emissions by 80% by 2050, and the construction industry being responsible for 50% of the UK's carbon emissions, it is of vital importance that positive changes are made. One of these changes is to reduce the carbon footprint of the materials used in construction. Lime mortar has been used for centuries, but since the arrival of cement, its use in modern construction has diminished, in part due to having lower compressive strengths than cement mortar. Air lime mortar, in particular, can be categorised as low energy due to the reabsorption of a significant amount of COE during the setting process: carbonation. The current study focuses on the impact of different types of aggregate (limestone and silicate) on air lime mortar strength. Previous research has found that higher strengths can be achieved with the use of limestone aggregate, but little is known about the reasons why. The research presented here looks at a microstructural analysis through use of SEM (scanning electron microscopy) in order to determine reasons behind the strength differences. At early stages of curing, there are clear differences at the interface of binder and aggregate.展开更多
基金Projects 50274036 supported by the National Natural Science Foundation of China11531Z02 by the Educational Committee of Heilongjiang Province2009RFXXG030 by the Special Foundation of Harbin Bureau of Science and Technology
文摘A study of the effects of the pulp nature on desulphurization and de-ashing during high-sulfur coal flotation is described in this paper. Highlighted are the use of a solution oxygen gauge, a pH value gauge and a surface tension gauge to investigate changes in the pulp nature related to changes in the oxygen content, the pH value and the interfacial tension. The temperature be- fore and after ultrasonic conditioning was also investigated. The results showed that ultrasonic conditioning resulted in a decrease in the oxygen content and the interracial tension and an increase in the pH value and the temperature of the pulp. The perfect index of flotation and the perfect index of desulphurization of fine coal increased by 25.19% and 18.03%, respectively, after the pulp was ultrasonically conditioned. This study shows that ultrasonic conditioning can change the pulp nature and enhance the degree of desulphurization during high-sulfur coal flotation.
基金Project(51376198)supported by the National Natural Science Foundation of ChinaProject(11JJ22029)supported by the Hunan Provincial Natural Science Foundation of China
文摘A novel vacuum ice slurry producing system with jet-pumps was proposed to deal with the problems of high energy consumption and ice blockage.In this novel system,one steam driven by a jet-pump was used to create vacuum in a hermetic vessel where water was sprayed through a nozzle to produce ice slurry,while the other steam was used to provide enough cold energy to make the left vapor in the hermetic vessel condense.Mathematical models of this novel system were established and theoretical simulation on the performance characteristics was also implemented based on the MATLAB program.Results show that the novel system is feasible and practicable,and the system performance is affected by many factors,such as the temperature of the generators,condensing temperature,evaporation temperature,and the cooling load of the refrigerator sub-system.The findings are helpful to improve the performance of ice slurry producing system.
文摘In recent years, the need for low energy materials has become increasingly important. With government targets aiming to reduce carbon emissions by 80% by 2050, and the construction industry being responsible for 50% of the UK's carbon emissions, it is of vital importance that positive changes are made. One of these changes is to reduce the carbon footprint of the materials used in construction. Lime mortar has been used for centuries, but since the arrival of cement, its use in modern construction has diminished, in part due to having lower compressive strengths than cement mortar. Air lime mortar, in particular, can be categorised as low energy due to the reabsorption of a significant amount of COE during the setting process: carbonation. The current study focuses on the impact of different types of aggregate (limestone and silicate) on air lime mortar strength. Previous research has found that higher strengths can be achieved with the use of limestone aggregate, but little is known about the reasons why. The research presented here looks at a microstructural analysis through use of SEM (scanning electron microscopy) in order to determine reasons behind the strength differences. At early stages of curing, there are clear differences at the interface of binder and aggregate.