Population balance modeling of homogeneous viral aggregation

Viral aggregation is a natural process which helps viruses to survive in the environment and to resist to disinfection. Aggregation is a complex phenomenon controlled by the isoelectric point of the viral suspension. Previous models describe the energies of interaction between viruses using the extended DLVO theory. However, they do not allow us to predict the evolution of the viral aggregates size, which is critical for viral survival and transport. In this paper, we present a model for homogeneous viral aggregation based on the population balance equation (PBE) to describe the evolution of aggregate size. The PBE was coupled with the extended-DLVO theory to account for the energy of interaction between viral particles affected by virus type and physicochemical conditions. The model was verified with literature data and no parameter fitting was required as all the model parameters are based on the physicochemical properties of the system. Overall, this model can be an useful tool to simulate viral aggregate evolution in water and in sediments. It can be extended to describe heterogeneous viral aggregation and coupled with transport models for the prediction of virus migration and persistence in groundwater.