Solution techniques for population balance equation: A case study for asphaltene aggregation

Population balance equation is widely used in modeling of particulate processes. In this work, the enlargement of asphaltene particles in a synthetic heptane-toluene mixture (Heptol) was experimentally investigated in a static mode and then modeled by using PBE. Aggregation is considered as sole responsible mechanism for size evolution. Three solution methods including two discretization methods, modified Hounslow (MH) method and Kumar cell average technique (KCAT), and one moment method, quadrature method of moments (QMOM), are considered. The simulation results were compared with experimental data to evaluate each method. The results of simulations indicate that moment method offers higher accuracy and less computational expense respect to discretized methods in prediction of asphaltenes aggregation. In the case of considering fractal structure, both methods inaccurately predicted the number and average diameter of asphaltene aggregates.