**5. Conclusions**

The hydrodynamics of the SAS process has been revised. Nozzle device, liquid flow rate and pressure effects on hydrodynamics have been taken into account. Flow regimes observable in the SAS related literature have been described. Dripping mode is simply due to the use of liquid flow rates that are too low to produce a continuous liquid flow and do not produce atomization. Rayleigh breakup, sinusoidal wave break up, and atomization regimes and, particularly their competition at some process conditions require a detailed analysis. The ability to identify and characterize these regimes drives future system improvements, including lighting enhancements laser-induced fluorescence, and higher spatial resolution cameras.

Morphology of the precipitated particles can be related to flow or mixing regimes. In the ampicillin case, two differentiated types of morphology can be identified in the precipitated experiments: spherical nanoparticles of ampicillin that are obtained from a fine precipitate with foamy texture, and particles of ampicillin with irregular forms and larger size, which are characteristic of the precipitate formed by aggregates, compact films, and rods. It has been correlated the morphologies of the particles obtained in the ampicillin precipitation assays and the estimated regimes as a function of the physicochemical properties and of the velocity of the jet, for a specific range of operating conditions.

However, the results from the application of these correlations cannot explain the morphologies of the precipitates obtained in some experiments. This fact can be due to important stabilization mechanisms as dynamic interfacial tension

Due to the great complexity of the SAS process, factors such as the ternary phase equilibrium, matter transfer between the phases, and the kinetics of nucleation and growth need to be considered, in addition to the limiting hydrodynamic conditions.
