During filtration, the release of deposited inclusions back to the main flow under certain conditions is called re-entrainment. In this study, re-entrainment was investigated experimentally in a pilot scale filter under continuous flow as well as interrupted flow conditions. Also, one-dimensional mathematical model simulating the global behaviour of filter bed was developed and validated by comparing its predictions with the experimental results. This model solves the mass conservation equations for the inclusions. A deposition/re-entrainment sub-model was incorporated into the filter model. The model predictions were in good agreement with the experimental data.