A conceptual sediment transport simulator based on the particle size distribution

Sediment transport is a very important process affecting the transport and retention of pollutants that easily adsorb to suspended sediment. The fine sediment plays a dominant role and needs to be properly represented. However, the conventional conceptual sediment transport models do not account for distributions of particle sizes and the differences in behaviour of the different fractions. Our paper presents an analytic solution for this problem using the log-normal probability density function to represent the particle size distribution of the sediment. Sedimentation and resuspension processes are calculated for the particle size distributions by using Hijulstrom diagram for incipient motion and deposition and integrating with Velikanov’s energy of sediment carrying capacity. An application on the Zenne River (Belgium) shows that our conceptual model provides a better representation of the high concentrations and the range of concentrations, as compared to a conventional conceptual sediment transport modelling.