Numerical simulation of pellet shrinkage within random packed beds

Catalytic pellets may experience volume contraction during reductive activation. Although known and easily accessible as the reduced bed height within industrial fixed-bed reactors, the effects on the bed structure are lacking discussion. A simulation routine is presented to predict the effects of pellet shrinkage within random packings on the pellet arrangement and flow hydrodynamics, using Blender for pellet deposition and shrinkage and OpenFOAM for flow simulation. After pellet shrinkage, packings show a high mean voidage and values for pressure drop below expectation. The feasibility of simulating pellet shrinkage within random packings is demonstrated, indicating its potential for reactor simulation.