To research a novel technology for dry coarse coal slime beneficiation and extend its application, active pulsing air separation technology was investigated by DEM-CFD coupling simulation approach. The results show th...To research a novel technology for dry coarse coal slime beneficiation and extend its application, active pulsing air separation technology was investigated by DEM-CFD coupling simulation approach. The results show that the ash content of feed is reduced by 10% 15% and the organic efficiency is up to 91.78% by using the active pulsing air separation technology. The gas solid flow in the active pulsing air classifier was simulated. Meanwhile, the characteristics of particle motion and the separation process of different particles were analyzed, and the mechanical structure of the classifier was also modified to achieve high separation efficiency. Therefore, a novel high-efficiency dry beneficiation technique was advanced for coarse coal slime.展开更多
Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1...Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1.00 mm coarse coal slime and the two different distributors. The experimental results show that the heterogeneity of axial particle velocity in the radial direction of the bed can be reduced by a distributor that has a central discharge. The beneficiation performance for this dis- tributor is improved relative to the distributor with the peripheral discharge. This indicates that it is necessary to eliminate or suppress the core-annulus structure within a hindered fluidized bed. Increasing superficial water velocity causes the clean coal ash content, the railings ash content, and the combustible recovery to increase. Additionally, increasing the bed height decreases all of these three indexes. The optimum superficial water velocity and bed height for a 0.25-1.00 mm coal feed were deter- mined to be 3 mm/s and 800 mm, respectively. This work provides a foundation for the scale-up of the bed.展开更多
基金Projects(51221462,51134022,51074156)supported by the National Natural Science Foundation of ChinaProject(2012CB214904)supported by the National Basic Research Program of ChinaProject(20120095130001)supported by Specialized Research Fund for the Doctoral Program of Higher Education,China
文摘To research a novel technology for dry coarse coal slime beneficiation and extend its application, active pulsing air separation technology was investigated by DEM-CFD coupling simulation approach. The results show that the ash content of feed is reduced by 10% 15% and the organic efficiency is up to 91.78% by using the active pulsing air separation technology. The gas solid flow in the active pulsing air classifier was simulated. Meanwhile, the characteristics of particle motion and the separation process of different particles were analyzed, and the mechanical structure of the classifier was also modified to achieve high separation efficiency. Therefore, a novel high-efficiency dry beneficiation technique was advanced for coarse coal slime.
文摘Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1.00 mm coarse coal slime and the two different distributors. The experimental results show that the heterogeneity of axial particle velocity in the radial direction of the bed can be reduced by a distributor that has a central discharge. The beneficiation performance for this dis- tributor is improved relative to the distributor with the peripheral discharge. This indicates that it is necessary to eliminate or suppress the core-annulus structure within a hindered fluidized bed. Increasing superficial water velocity causes the clean coal ash content, the railings ash content, and the combustible recovery to increase. Additionally, increasing the bed height decreases all of these three indexes. The optimum superficial water velocity and bed height for a 0.25-1.00 mm coal feed were deter- mined to be 3 mm/s and 800 mm, respectively. This work provides a foundation for the scale-up of the bed.