Fate and Transportation of Viruses from Reclaimed Water into a Floatation System

Abstract

The fate and transport of viruses in floatation systems is considerably important for accurate determination of the safety of reusing reclaimed water in the flotation process. Herein, simulation experiments on the floatation, adsorption and desorption were performed to examine the effect of initial virus concentration, pH and floatation reagents on the adsorption of viruses ΦΧ174 and MS2 onto copper–molybdenum ores. The transport of viruses in the flotation systems was also investigated. The viruses in the reclaimed water were rapidly adsorbed onto the ore particles, suggesting that tailing wastewater can be safely reused for floatation. However, the adsorbed viruses in the concentrates, middlings and tailings may pose health risks at certain exposure levels. The transport of viruses was dominated by their attachment to ore particles, with most being inactivated or irreversibly adsorbed. The removal and adsorption rates decreased as the initial virus concentration increased, and the removal rate decreased as pH was increased from 7.5 to 9.5. In comparison with MS2, ΦΧ174 was removed more effectively. This suggested that electrostatic repulsion is an important mechanism because MS2 has a greater negative charge. The attachment of both ΦΧ174 and MS2 onto the mineral particles increased significantly in the presence of PJ053 and CaO.