Effectiveness of Xanthan Gum and Guar Gum in Mitigating Dust Emission from Bauxite Residue Tailings Facility

Fugitive dust and particulate emissions from tailing storage facilities prompt several environmental and public safety concerns. The various traditional techniques being employed are only applicable to impoundments of already closed, effective for a limited period and require expensive chemicals. In the recent past, biopolymers have emerged as an environmentally benign alternative to alleviate particulate emissions from soils and wastes. This study investigates the effectiveness of two biopolymers, namely: Xanthan gum and Guar gum, in mitigating the particulate emissions from a bauxite residue storage facility. To understand their effectiveness, two types of experiments, one to study the moisture retention ability and the other to examine the resistance to wind lifting of biopolymer-treated bauxite residue particles, are conducted. Biopolymer concentrations of 0.01, 0.05, and 0.1%, a rate of application of 1.5 L/m², a wind speed of 4.5 m/s, and a temperature of 45 °C are considered for the study purpose. It is found that an increase in biopolymer concentration increases the resistance of particles against dust emission. Interpretation of results portrays that 0.1% is the optimal content and 10 to 15 days is the optimal reapplication interval corresponding to both biopolymers. Microstructure analyses reveal that particle encapsulation is the chief mechanism behind the bonding of biopolymers with bauxite residue particles and thereby controlling the lifting of dust over the tailings facility.