Gas-liquid microdispersion and countercurrent flow in a miniaturized annular rotating device

The major challenge for the existing gas-liquid microdispersion devices is that they cannot achieve efficient dispersion performance at high volume ratio of gas to liquid. In this context, a miniaturized annular rotating device (m-ARD) with a high handling capacity, large specific surface area, relatively narrow bubble size distri-bution, and operating in a countercurrent flow mode had been proposed to achieve efficient gas-liquid micro-dispersion performance at the high phase ratio of gas to liquid. Variables were investigated to determine the gas hold-up, bubble size and its distribution, and specific surface area. The gas-liquid microdispersion mechanism in the m-ARD was also discussed. Two typical bubble generation routes, namely, churn and dripping flow were observed and a transition map was constructed. Furthermore, the handling capacity, average bubble size, and specific surface area could be up to 30 mL/min, 0.59 mm, and 1000 m2/m3, respectively. More gas inlets could be beneficial for much higher handling capacity. In addition, for predicting the gas hold-up and average bubble size, two dimensionless equations were proposed.