Experimental and modeling investigation of moisture-induced interparticle forces in the fluidization and de-aeration of irregular, rough particles

Handling wet, irregular, and rough particles in processes like pneumatic conveying and hopper discharge is challenging due to clogging, reduced flowability, and liquid bridge forces. Air injectors assist by fluidizing materials, but their effectiveness depends on understanding moisture’s impact on fluidization and de-aeration. This study investigates moisture-induced interparticle forces on fluidization and de-aeration of irregular, rough particles, using drill cuttings. Ten moisture levels spanning pendular, funicular, and capillary states were analyzed for their effects on packed bed, fluidization, and de-aeration characteristics. Results identified three moisture categories: dry (1.3–7.7%), cohesive (7.7–27.6%), and slurry (27.6–44.0%). Moisture minimally affected the dry state but hindered fluidization and air retention in the cohesive state. In the slurry state, fluidization caused high-pressure drops, and air retention increased via bubble formation. Modeling showed that accounting for liquid bridges between particles and asperities accurately predicted interparticle forces. These findings improve the handling and modeling of wet, rough particles.