Advanced wastewater treatment stage for textile industry

Abstract

Dissolved air flotation represents an important stage for wastewater treatment and was used during the last sixty years for different pollutants such as: suspended solids, greases, oils etc. Nowadays, the dissolved air systems are generally applied in industrial wastewater treatment plants, where the amount of pollutants is above the average (textile and leather industry). The research team members developed an innovative DAF unit and realized a laboratory demonstrator (figure 1). The laboratory installation was tested and the efficiency of wastewater treatment was demonstrated. The latest researches proved that flotation reagents have an essential role in the removal of different pollutants. The scientific literature demonstrates that these reagents can be used to remove the pollutants as sludge or foam, Reagents are divided into modifiers, flocculants, depressants, collectors and frothers, depending on their role the flotation process. Nanomaterial utilization in wastewater treatment has become an intensely studied topic. Collectors reagents, based on hydrophobic nanoparticles, can adsorb a larger quantity of pollutants due to the hydrophilic particle surfaces that facilitate the attachment of pollutants to air bubbles generated by the DAF unit. In the present paper, the researchers present that the role of nanoparticles is to facilitate particle-bubble attachment and/or to minimize detachment. The goal of the study is to consider the influence of nanoparticle parameters on the various stages of particle flotation to demonstrate the key role of nanoparticles in removal of pollutants from textile wastewaters.