喷孔直径对水力喷射空气旋流器传质性能的影响

Optimization of Jet Hole Diameter of a Water-Sparged Aerocyclone Reactor

水力喷射空气旋流器(WSA)是一种高效的超重力气液传质设备,为了进一步提高其传质效率,通过理论分析和吹脱氨实验研究,对其喷孔直径进行了优化研究。采用因次分析法对实验数据进行了归纳,得到了脱氨传质系数KLa的经验公式为:KLa=2.77×10-9uLI0-1Reg0.37ReL1.18Wel-1.05,运用该式可较好地预测喷孔直径对WSA脱氨传质性能的影响。研究发现,当废水射流流速恒定时,KLa随喷孔直径增大而增大,但当超过某一直径时,其增幅减小。综合考虑过程的能耗与传质效果之间的关系,喷孔直径的最佳取值应按dh=l06.39设计计算,l0为WSA的环隙宽度。

Water-sparged aerocyclone （WSA） is a new type of air stripping equipment with high efficiency in ammonia removal. In order to enhance the mass transfer efficiency between gas and liquid phases in the WSA, the optimization of jet hole diameter was carried out through theoretical analysis and air stripping experiments of aqueous ammonia. Results show that the mass transfer efficiency of the WSA increases with increasing jet hole diameter under a certain liquid jet velocity in air stripping of aqueous ammonia. However, excessive jet hole diameter will consume more energy for the recirculation of wastewater. The optimum jet hole diameter can be calculated as dh=10/6.39, here 10 is the annular width of the WSA. To predict the effects of jet holes diameter on mass transfer characteristics in WSA, empirical formula correlating the volumetric mass transfer coefficient and the structural and operational parameters was developed as KLa = 2.77 × l0-9 t/L/0-I Reg0.37ReLIlsWeL1.05.