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Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effects of dodecylamine (DDA) and 2-octanol on the characteristics and dispersion of bubbles in a flotation column was investigated in this study. Bubble size distribution was measured using the McGill bubble size analyzer, surface tension was measured using the surface tensionmeter, and aeration rate was researched using the measuring cylinder technique. Furthermore, bubble adsorption density and surface area flux were analyzed. With the increase in reagent concentration, the bubble size decreased until the critical coalescence concentration (CCC) to 0.630 3 and 0.602 0 mm of DDA and 2-octanol, respectively, and the concentrations (CCC99), at which bubble size is reduced by 99% from that with water only, were analyzed to be 0.081 1 and 0.070 3 mmol/L for DDA and 2-octanol, respectively. The bubble size in DDA solution was found to be larger than that in 2-octanol solution with an equal solution concentration. Surface tension was found to linearly decrease with the increase in reagent concentration, and the surface tension of DDA was lower than that of 2-octanol under the same concentration. Aeration rate increased as the reagent concentration increased, and the aeration rate of DDA was larger than that of 2-octanol. The adsorption density of DDA and 2-octanol at CCC was calculated to be 0.966 2 and 0. 282 7 μmol/m2, and the bubble surface area flux of DDA was smaller than that of 2-octanol while the concentration was above CCC. With the increase of DDA addition in 2-octanol solution, the CCC, constant D32, surface tension and adsorption density decreased, but aeration rate and bubble surface area flux increased. With a DDA addition of 0.032 4 mmol/L, the minimum CCC, constant D32 and adsorption density were obtained at 0.021 6 mmol/L, 0.583 3 mm and 0. 154 0 μmol/m2, respectively, while the maximum bubble surface area flux was calculated to be 7.734 s-1. [ABSTRACT FROM AUTHOR]

A double cosine self-suction nozzle was designed based on the spraying inspiration. The influence of operating parameters on the bubble size distribution in a double cosine self-suction nozzle was analyzed using methyl isobutyl carbinol(MIBC) as the frother. Bubble Sauter mean diameter of nozzle was investigated at different concentrations of frother, inflow pressure, sampling height, nozzle distance, and the suction capacity of the nozzle was researched under different inflow pressures using the image analysis technique. The results show that with the increase of frother concentration, the Sauter mean diameter(d32) decreases until the critical coalescence concentration(CCC) was determined as 0.112 mmol/L above which the d32 is constant. With a higher inflow pressure, the constant is lower and the scope of bubble size distribution becomes narrow with the increases of the smaller bubble content. For example, the Sauter mean diameter was 0.32 mm and the content of bubble middle size distribution was 40.73% when the inflow pressure P is 0.14 MPa. The d32 decreases with the increase of inflow pressure, nozzle distance and sampling height. The decrease(increase) tread changes slower when the frother concentration reaches the CCC. With the inflow pressure the inspiratory capacity increases linearly, and the inspiratory capacity is larger when the nozzle distance increases. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the characteristics of spraying inspiration and stirring inspiration,a novel jet-stirring coupling flotation device was designed.In order to study its inspiration method,its air-suction mechanism was analyzed theoretically,and also the experimental investigation of the device on the relationship between coupling inspiratory capacity and jet flow and the relationship between stirring inspiratory capacity and impeller rotational speed was conducted by controlling the input frequency of circulating pump motor to adjust jet flow and control liquid level.The results show that the stirring inspiratory capacity increases in a quadratic function with the increase of impeller rotational speed,and the coupling inspiratory capacity increases in an approximate linear with the increase of jet flow;influenced by impeller rotation and liquid level,the coupling inspiratory region and stirring inspiratory region inhale air together under a shallow level (hy≤140 mm),and the coupling inspiratory region inhales air while the stirring inspiratory capacity is low or even zero under deep level (hy>140 mm);and the coupling inspiratory capacity increases first and then decreases with liquid level goes up at low jet flow (motor frequency is less than 35 Hz),and increases with the increase of liquid level at high jet flow (motor frequency is more than 30 Hz);however,the stirring inspiration capacity is sharply reduced with liquid level rising.The maximum total inspiratory capacity is about 4.03 L/min in the deepest liquid level 230 mm and the maximum frequency 50 Hz,and basically satisfies the requirement of air-suction for flotation.The study of air-suction mechanism provides a fundamental basis for a further separation study of the device. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

According to repeated coal cleaning and low flotation efficiency due to no-classified slurry separation，a novel slurry classification pond was proposed. Based on the hydraulic separation principle and the viscous fluid resistance principle，the slurry classification pond，square shape and regular hexagon shape pipes were designed. The flow field of the slurry classification pond with different shape pipes was numerically simulated，and distribution characteristics the velocity，reynolds number，route energy loss and other hydrodynamic parameters were analyzed. The results show that both square and regular hexagon shape pipes can control the flow state well. When the regular hexagon shape pipes are used，the velocity difference is great，but the mean route energy loss is small. When the square shape pipes are used，the velocity gradient is smaller，the mean route energy loss is larger，and the flow field is smoother. So the square shape pipes are better for the accurate classification of particles. Based on the analysis，the continuous classification of slurry by the slurry classification pond developed is feasible，and it suggests that an actual test should be conducted. [ABSTRACT FROM AUTHOR]

The influence of operating parameters on bubble distribution in a mechanical flotation device was investigated using 2-Octanol as the frother. Bubble size distribution was analyzed using the image analysis technique , and surface tension was measured using the surface tension meter. While the reagent concentration increases from 0.011to 0. 154 mmol/L, the surface tension decreases from 73. 577 to 72. 544 mN/m. Meanwhile, the Sauter mean diameter ( d32) decreases up to the critical coalescence concentration (CCC) of 0. 103 mmol/L above which the d32 is constant at 0. 593 mm. The adsorption density is calculated at 0. 255 p .m o l/n r . With the increase in impeller rotate speed from 1 494 to 2 494 r /m in ,the d32 linearly decreases and more slowly with higher concentration. The d v increases with air intake from 0. 1 to 0 .9 l /m in and more with lower concentration. The d32 is also found positively and linearly related with the sampling height from 0 to 20 cm ,b u t it increases more slowly with higher reagent concentration. In the studied range of all the operating parameters, the sampling height reflects the most significant effect on the d32 when the reagent concentration is lower than CCC, but that of the reagent concentration higher than CCC is inspiration capacity. The rotate speed of the impeller is found as the least significant operating parameter influencing the d32. [ABSTRACT FROM AUTHOR]