作业工况及喷射方式对气举输出的影响

基于流体力学理论,从静力学角度,进行了气举管内压力分析,研究了不同作业工况及喷射方式对气举输出的影响,分析了气举输出特性随吸口下降深度的变化规律。结果表明,气举垂直作业存在固相与液相流量变化趋势相反的平衡段,吸口底部漏斗状坑径变大、局部流体加速、紊流增多,有利于固体颗粒的提升; 对称喷射方式固相空隙率更高,提升固体颗粒性能更好,而非对称喷射方式明显增强了气举吸口附近的局部扰动,更有利于采矿作业过程中液体提升。

Influence of Working Condition and Injection Mode on Air Lifting

Based on the theory of fluid mechanics, the pressure in air lifting pipe was analyzed from a statics point of view. The influence of different working conditions and injection modes on air lifting was investigated, and the variation pattern of the air lifting characteristics against the submerged depth of suction port was analyzed. The results show that in the vertical air lifting operation, there is an equilibrium section, in which the variation of the flow rate of solid phase and liquid phase follows a completely opposite trend. When the diameter of funnel-shaped openning at the bottom of the suction part increases, the fluid accelerates and the turbulence increases in local region, which is beneficial to lifting of solid particles. Symmetrical injection mode can lead to a higher solid void ratio and improve the lifting performance of solid particles, while asymmetrical injection mode obviously enhances the local disturbance near the airlift suction port, which is more conducive to lifting of liquid during mining operations.