Abstract: Red mud consists of fine particles (d₅₀ =13.02 μm) and exhibits a high concentration high viscosity paste solid-liquid two-phase flow in piping transport. The testing of its rheological property indicates that testing methods such as rotational viscometer can not reflect its real flow state in piping, with the measured rheological parameters larger than real ones. Based on the tube flow measurement principles, self-developed tube type pressure rheological testing facility was used to measure the rheological properties of red mud at different concentrations (60.2%, 63.6% and 66.8%) and the constitutional equation was obtained. It is concluded that the red mud, when flowing in piping, exhibits the properties of non-Newtonian pseudoplastic fluid and its consistency coefficient and flow index will vary greatly with the concentration.

Key words: High concentration, Non-Newtonian pseudoplastic fluid, Tube flow method, Tube type pressure rheological test facility