Clogging of microchannels by nano-particles due to hetero-coagulation in elongational flow

► Clogging of microchannels during processing of concentrated dispersions. ► Hetero-coagulation of primary particles and small fractions of micron-sized impurities in the converging flow field at the channel entrance. ► Aggregation can be avoided by ► Reducing the amount of micron-sized particles. ► Improving colloidal stability of primary particles. ► Applying high flow rates and steep entrance angles.