Numerical simulation and optimization of red mud separation thickener with self-dilute feed

In order to acquire the flow pattern and investigate the settling behavior of the red mud in the separation thickener, computational fluid dynamics （CFD）, custom subroutines and agglomerates settling theory were employed to simulate the three-dimensional flow field in an industrial scale thickener with the introduction of a self-dilute feed system. The simulation results show good agreement with the measurement onsite and the flow patterns of the thickener are presented and discussed on both velocity and concentration field. Optimization experiments on feed well and self-dilute system were also carried out, and indicate that the optimal thickener system can dilute the solid concentration in feed well from 110 g/L to 86 g/L which would help the agglomerates＇ formation and improve the red mud settling speed. Furthermore, the additional power of recirculation pump can be saved and flocculants dosage was reduced from 105g/t to 85g/t in the operation.