Characterization of Red Mud treated under high temperature fluidization

• Red Mud is subjected to different temperatures in a FBR.
• Characterization of fluidized samples by XRD, TG–DTA, FESEM, FT-IR, and BET apparatus
• Analysis on temperature effects for particle size/surface area/composition of samples

Red Mud (RM) is fluidized at different temperatures in a fluidized bed reactor (FBR). The phase composition and structural transition of RM fluidized at different temperatures are investigated. RM is treated in the FBR at different temperatures and above minimum fluidization velocity. The characteristic properties of RM treated in FBR at different temperatures are analyzed using XRD, TGA–DTA, PSA, FESEM, FT-IR and BET apparatus. It is observed that the different components of RM decompose on treatment of high temperature. The results thus obtained from RM treated at room and at higher temperatures are found to be much more promising where the temperature required for the decomposition of certain components is much less than the conventional heating methods. It is observed that gibbsite (Al(OH)3) decomposes into Al2O3 & H2O and calcite decomposes into CaO and CO2 at higher temperatures. The particle size of treated RM is also analyzed where the particle size is found to increase initially and then decrease with the increase in temperature. The results obtained will thus provide an important base for the comprehensive utilization of RM for different applications.

Red Mud obtained from Aluminum Industry is used as a bed material inside a stainless steel fluidized bed reactor which can be operated up to a maximum temperature of 500 °C. The bed is made to fluidize using an air blower whose flow rate can be controlled by a globe valve connected below the fluidized bed. Two heaters (a coil heater and a ceramic heater) are connected to the reactor, the temperature of which is controlled using a PID controller.Figure optionsDownload as PowerPoint slide