关键词:

液液循环流化床, 液液雾化, 液滴, 粒径分布

Abstract:

Drop formation in liquid-liquid atomization processes is one of the key techniques of liquid-liquid circulating fluid bed (CFB).A high resolution digital camera and image processing were used to investigate the process of drop formation in a normal CFB experimental system. The photos and sizes of drops in the whole flux range were obtained from experiments, and the distribution function was used to analyze the drop-size distribution (DSD).Experimental results indicated that DSD from a specific flux was in good agreement with Rosin-Rammler distribution function, and the areas of drop formation were divided into single drop formation section, transition section, and multiple drop formation section. It was found that with increasing flux, the uniformity of drops decreased at first and then increased and the median diameter of drops always decreased in both single drop formation section and multiple drop formation section. The uniformity and median diameter of drops in the multiple drop formation section changed insignificantly, whereas they remained unchanged in the transition section. And the diameters of drops formed were mostly between 0.7 mm and 1.0 mm while the flux of water was 50 ml·min-1.The research results provide a reasonable flux range of drop formation for practical operation of CFB based on the design demand of particle-size.

Key words:

液液循环流化床, 液液雾化, 液滴, 粒径分布