Hydrodynamic cavitaion venturi tube technique is used for pico and nano bubble generations in coal column flotation. In order to determine the optimal design of hydrodynamic cavitation venture tube for pico and nano b...Hydrodynamic cavitaion venturi tube technique is used for pico and nano bubble generations in coal column flotation. In order to determine the optimal design of hydrodynamic cavitation venture tube for pico and nano bubble generation, a four-factor three-level Central Composite Design of Experimental was conducted for investigating four important design parameters of cavitation venturi tube governing the median size and the volume of pico and nano bubbles. The test results showed that maximum volume of pico and nano bubbles, 65–75%, and minimum mean pico and nano bubble size,150–240 nm, were achieved at the medium ratio of the diameter of outlet of the venturi-tube and diameter of throat(3–4), medium outlet angle(11–13°), high inlet angle(26–27°) and high ratio of the length of the throat and the diameter of throat(2.3–3). Study the effects of the producing pico and nano bubbles on fine coal flotation was performed in a 5 cm diameter 260 cm height flotation column. The optimal percentage of pico and nano bubbles was about 70%, which produced maximum combustible material recovery of 86% with clean coal ash content of 11.7%.展开更多
A low grade graphite ore from eastern India was beneficiated by flotation to improve its quality. The ore was composed of 87.80%ash and 8.59%fixed carbon. Primary coarse wet grinding （d80：186 μm） followed by rough...A low grade graphite ore from eastern India was beneficiated by flotation to improve its quality. The ore was composed of 87.80%ash and 8.59%fixed carbon. Primary coarse wet grinding （d80：186 μm） followed by rougher flotation in Denver flotation cell using diesel as collector and pine oil as frother yielded a rougher concentrate. Regrinding （d80：144 μm） of this rougher concentrate was opted for further libera-tion of graphite. It was followed by cleaning in laboratory flotation column. This combined process of relatively coarse primary grinding followed by regrinding and cleaning in flotation column resulted in final concentrate of 7.44% yield with 89.65% fixed carbon and 6.00% ash. This approach of two-stage grinding to recover the flake graphite at the coarsest possible grind can help to minimize grinding energy costs. A conceptual flow sheet which is cost effective was developed based on this methodology.展开更多
基金West Virginia State Coal and Energy Research Bureau(WVCERB)the Department of Mining Engineering,West Virginia University
文摘Hydrodynamic cavitaion venturi tube technique is used for pico and nano bubble generations in coal column flotation. In order to determine the optimal design of hydrodynamic cavitation venture tube for pico and nano bubble generation, a four-factor three-level Central Composite Design of Experimental was conducted for investigating four important design parameters of cavitation venturi tube governing the median size and the volume of pico and nano bubbles. The test results showed that maximum volume of pico and nano bubbles, 65–75%, and minimum mean pico and nano bubble size,150–240 nm, were achieved at the medium ratio of the diameter of outlet of the venturi-tube and diameter of throat(3–4), medium outlet angle(11–13°), high inlet angle(26–27°) and high ratio of the length of the throat and the diameter of throat(2.3–3). Study the effects of the producing pico and nano bubbles on fine coal flotation was performed in a 5 cm diameter 260 cm height flotation column. The optimal percentage of pico and nano bubbles was about 70%, which produced maximum combustible material recovery of 86% with clean coal ash content of 11.7%.
文摘A low grade graphite ore from eastern India was beneficiated by flotation to improve its quality. The ore was composed of 87.80%ash and 8.59%fixed carbon. Primary coarse wet grinding （d80：186 μm） followed by rougher flotation in Denver flotation cell using diesel as collector and pine oil as frother yielded a rougher concentrate. Regrinding （d80：144 μm） of this rougher concentrate was opted for further libera-tion of graphite. It was followed by cleaning in laboratory flotation column. This combined process of relatively coarse primary grinding followed by regrinding and cleaning in flotation column resulted in final concentrate of 7.44% yield with 89.65% fixed carbon and 6.00% ash. This approach of two-stage grinding to recover the flake graphite at the coarsest possible grind can help to minimize grinding energy costs. A conceptual flow sheet which is cost effective was developed based on this methodology.
