Parametric study of the oleophilic skimming process: CFD simulation using VOF model

Oleophilic skimming is a primary alternative when addressing oil spill accidents. However, the existing literature does not define accurately the optimum design and operating conditions of the oleophilic skimmer. In this research, an extensive CFD investigation was conducted on the performance of the drum skimmer. Seven parameters were tested, namely drum diameter, drum centre height, oil slick thickness, rotational speed, oil density, oil viscosity and oil surface tension. The simulations were performed by applying the volume of fluid technique using the OpenFOAM package. The two-dimensional numerical setup was tested for grid size, domain extension and time-step convergence, and the results were validated with experimental data from the literature. The skimmer performance was evaluated through the oil recovery rate and water ingestion rate. The study illustrated that the oleophilic drum skimmer best functions at rotational speed within 30-60 rpm, drum diameter within 200-300 mm, drum centre-height-to-diameter ratio within 0.3-0.4, oil slick thickness = 15 mm and oil viscosity within 10-100 cSt.