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Spray drying is a conventional technique for producing dried particles from an aqueous feed.It varies,in scale,from a few grams per hour to tens of tons of dried product per hour.The yield of the technique is very high compared with some of the wet production routines for making functional particles.One drawback of the technology is that the atomization systems (pressurized nozzles or rotational discs) produce a wide range of the particles sizes.The large and small particles do not follow the same sort of trajectories inside the drying chamber.The thermal and water content histories and the chemical reaction history are quite different among the particles.The morphologies also vary greatly among the particles produced.Even for the small laboratory spray dryer,which has been used widely in scientific and product development laboratories has similar problems as that in the large industrial dryers.In scientific laboratory,it is highly desirable to produce uniform sized droplets and uniform morphology (and function) of the dried particles,and simple quantifiable trajectories of the particles.This will allow much more definitive scientific conclusions to be drawn to understand the particle formation fundamentals.Here,a unique and robust system is described where a single stream of mono-disperse droplets is generated and then made in contact with hot air to make rapid transformation of liquid droplets to solid particles.This system is very effective,either as a primary or a preforming stage in particle engineering that has helped produce very uniform particles for scientific exploratory purposes and more definitive product developments.It is also becoming a critical part of a process optimization toolbox for large-scale operations.In this talk,the mechanisms of droplet generation and the operational rules of thumb will be presented.A wide range of examples of the particles made so far will be showcased.Finally,a scope for scale-up production of the uniform particles using similar techniques will be presented for greater interest in the technology community.