Single drop breakup experiments in stirred liquid-liquid tank

The breakup process has been investigated by single drop experiments in a stirred liquid-liquid tank. The time taken to deform, stretch and produce two or more fragments was measured. For each of the observed breakup events, the number of drops in the resulting population was registered. The occurrence of equal and unequal breakup events was also noticed. Four oil-in-water systems were studied: toluene, petroleum, n-dodecane, and octanol. The mean energy dissipation rate of the tank was 1.14 m2/s3 and the diameter of the observed mother drops that breakup were mainly in the range of 1-4 mm. Multiple breakup events were the most frequent outcome in the experiments. It was observed that the number of daughter drops produced in a breakup was dependent on the mother drop size. The breakup time increased with the mother drop size and was in the approximate range of 10-100 ms. A large uncertainty in the measurements is associated with the determination of the final breakup time, particularly in the cases of high order breakup events. Most breakup events took place in the large velocity field close to the radial impeller. It is not evident whether the breakup events were due to the time average shear or pressure and velocity fluctuations.