Agglomeration (also known as lumping) is the bonding together of particles of similar composition into larger, aggregate particles (lumps). Agglomeration is frequently observed when one or more of the ingredients in a blend are cohesive (sticky), hydrophilic (attracted to water), or have a tendency to acquire electrostatic charge.
Mixing Mechanics: Practical powder blending: Ingredient agglomeration
Except for studies focusing on granulation, ingredient agglomeration hasn’t been researched in much detail and has been the focus of very few academic or industrial articles. In fact, drug agglomeration in pharmaceutical manufacturing has only recently been recognized as a common problem.