Effects of Rollers Speed Regime on the Roller Screen Efficiency
Meysam Javaheri, Akbar Jafari, Gholam Hossein Baradaran, A. Saidi
Abstract
Roller screen is a key device in pelletizing plants employed to size classification of green pellets. Realistic observations showed that some pellets with size slightly larger than the gap were trapped between the rollers and caused blockage and decreasing the device efficiency consequently. Here, a speed regime for the rollers is proposed and its effects on the device efficiency were studied numerically. To perform the simulations, discrete element method was used and to ensure the results accuracy, surface meshing and the time step sensitivity analysis were performed. Using the numerical results, impact of each of the variables independently and also their cross effects were studied and discussed. The results proved that the proposed gradient speed regime improves the efficiency considerably. However, both the speed regime and the deck angle should be adjusted in optimum values to achieve maximum efficiency.