Soap and detergent manufacturing consists of many unit operations such as mixing, heat transfer, drying, and separation. For example, powdered detergent manufacturing includes two main processes: mixing in a continuous feed mixer (called a crutcher) and then spray drying of the resulting slurry to produce granules. CFD can play an effective role in the optimization of parameters for these processes, such as the initial droplet diameter, the location and orientation of sprays, and the mass flow rate of the sprayed material, as well as the final particle size and moisture content.
In liquid detergent manufacturing, dry and liquid ingredients are blended to a uniform mixture using static mixers .
Detailed model of a crutcher (Fig a) along with mass fraction of surfactant species (cleansing agents) showing the mixing that takes place (Fig b), and temperature differential due to steam jacket and incoming liquid streams (Fig c).
Particle tracks (colored by particle size) in a spray dryer as a function of injection velocity. By reducing the injection velocity from higher velocity (Fig d) to a lower velocity (Fig e) in the simulation, the evaporation process is optimized. The model also predicts moisture that has evaporated from the particles inside this spray dryer (Fig f).
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