Study of the water cleaning process by using CFD-DEM method: A case study of coarse filter material

Abstract

In this paper, the CFD-DEM coupling method was utilized to study the water cleaning and regeneration process of fibrous filter material. The effects of cleaning flow rate, time and adhesion force on the particle removal process were simulated. The results showed that the particle removal rate had a diminishing marginal effect with the increasing of cleaning flow rate. More than 80% of the particles were removed in the initial period, and then tended to stabilize. The higher the flow rate, the shorter the time needed to achieve stability. For G4 filter material, the function between the particle removal rate and the cleaning flow rate and time was given, and the best cleaning flow rate was 1.2 m/s while the cleaning time was 30 s. The surface energy of the fibers plays a dominant role in the cleaning process, and the reduction to 1/4 of the surface energy of the particles can effectively improve the cleaning and regeneration performance.