This research investigates the breakup modes of a liquid column and
the formation of droplets in the process of micro-encapsulation. An
assembly micro-atomizer is used under single-fluid and twin-fluid
operational conditions using glycerin and alginate solution. Images of liquid
column were taken by a high speed camera to investigate the breakup
mechanism and formation processes of droplets. Results show that the
formation of the droplets depends on the instability mode of the liquid
column, including asymmetry mode, helical mode, sinusoidal mode and
spray developing mode as Reynolds number was increased from 221 to
2210. The increased tendency of intact-length with Re reversed in the
transition region, which is the desired condition for the formation of
mono-size droplets. Moreover, the production of micro-capsulate is
successfully by single-fluid extrusion method as well as twin-fluid
atomization process, in which SMD equal to 20μm can be achieved in low
gas-to-liquid ratio (GLR). It is not easy to achieve by commercial apparatus.