Abstract: Water-sparged aerocyclone(WSA)is a new type of air stripping equipment with high efficiency for ammonia removal.In order to improve its mass transfer performance and establish design principles,spray hole distribution of WSA was optimized by means of theoretical analysis and experimental method.A new concept,critical distance of spray holes,l_c,and its calculation formula were put forward.The results show that the WSA with square arrangement of spray holes exhibits higher mass transfer efficiency than that with triangle arrangement of spray holes in air stripping of ammonia.The distance between adjacent spray holes of the WSA has obvious effect on volumetric mass transfer coefficient.The optimal distance is about 1.28l_c and the perforation area is about 78% of the central tube height in the WSA.These results could be used as a guide for the design of WSA with good mass transfer performance.

Key words: water-sparged aerocyclone, jet, spray hole distribution, gas-liquid mass transfer, air stripping of ammonia

摘要： 为了进一步提高水力喷射空气旋流器(WSA)的传质性能,采用理论分析与实验相结合的方法,对其喷孔分布进行了优化研究。提出了基于同层相邻喷孔液相射流边界层相交于中心排气管表面的临界孔间距l_c的概念及其计算方法,实验考察了喷孔排列方式和喷孔间距对WSA脱氨传质效果的影响。研究表明,在传质性能上,WSA的射流喷孔按正方形排列优于三角形排列;喷孔间距对脱氨传质效率有明显影响,存在一个较优取值,其值约等于1.28l_c;从上往下到中心排气管出口处计算,侧壁开孔区长度应该占中心排气管长度的78%。研究结果为设计具有良好传质性能的WSA提供了依据。

关键词: 水力喷射空气旋流器, 射流, 喷孔分布, 气液传质, 废水脱氨