底部挡板与进气位置对水力喷射空气旋流器传质性能的影响

Effect of bottom baffles and air inlet position on mass transfer performance of a water-sparged aerocyclone

水力喷射空气旋流器(water-sparged aerocyclone,WSA)是一种利用液体射流在气体旋流场中雾化强化气液传质的新型传质设备,可广泛用于废水、废气处理等环境工程中。为了改进水力喷射空气旋流器结构,提高其气液传质性能,本文通过废水氨氮吹脱实验研究了进气口轴向位置以及底部挡板的设置对气液传质性能的影响。实验结果表明,进气位置与底部挡板对水力喷射空气旋流器的气液传质性能存在影响。在相同工作条件下,气相进口沿轴向下移对WSA内气液传质性能作用较小,但能够使其气相压降降低约为10%。在WSA主筒体底部液封区域设置挡板,能够强化WSA底部气液两相的混合,进而提高低液相循环流量下WSA内的气液传质性能,且随进气速度的增加,其效果越显著,研究结果可为设计传质性能良好的WSA提供设计依据。

Water-sparged aerocyclone（WSA） is a new type of gas-liquid mass transfer equipment with a coupling field of liquid jet with gas cyclone,which can be widely used in wastewater treatment process. To further optimize the structure design of WSA,the effect of bottom baffles and air inlet position on mass transfer performance of WSA was comparatively studied by air stripping of ammonia from wastewater. The results indicated that the separation space configuration of a WSA affects its mass transfer performances. Under the same conditions,the axial air inlet position has no effect on mass transfer performance,but moving air inlet position downward could reduce the gas pressure drop in WSA by about 10%,which was probably caused by abating the friction loss between the gas cyclone and the wall. In case of high air inlet velocity and low liquid flow rate,the bottom baffles in the WSA could intensify the mixing effect between gas and liquid phases,thereby improving the mass transfer performance,and the effect is more pronounced with the increase of air inlet velocity. The results could be used as a guide for the design of WSA with good mass transfer performance.