XANTHAN GUM AS A NOVEL FLOCCULANT AID EMPLOYED IN DRINKING WATER TREATMENT

Resumo

Aluminum salts used for drinking water treatment are strongly related to environmental implications and health hazards. In order to reduce aluminum concentration in water and enhance the quality of the flocs formed, flocculant additives are employed. This paper evaluated polyaluminum chloride as coagulant in combination with xanthan gum as a novel flocculant to improve drinking water quality. Optimum results for color removal of 97.4 %, were observed with 5.0 ppm of polyaluminum chloride combined with 0.6 ppm of xanthan gum, prepared at 65 ºC. Turbidity removal was complete with 5.0 ppm of polyaluminum chloride combined with xanthan gum solution, prepared at 65 ºC in all evaluated concentrations. Moreover, PACl combined with xanthan gum at 0.6 ppm, prepared at 65 ºC, enhanced the removal of other contaminants, which could improve posterior stages of water treatment, as filtration and disinfection, resulting in greater control of organic load and DBPs formation.