Treatment of wastewater from textile factories using modified bentonite

Abstract

The modern textile industry uses large quantities of water and produces significant volumes of wastewater at various stages of production. This especially applies to the dyeing stages and fabrics processing. In the wastewater of the OJSC “S.M. Kirov Spinning and Thread Combine” significant excesses were revealed in almost all studied indicators, except for calcium and nitrites. The excess of Cu2+ copper ions reaches 800 times. Laboratory studies of the effectiveness of sorption materials with respect to Cu2+ ions were carried out using model solutions of CuSO4∙5H2O. Research has made it possible to establish bentonite, granulated, calcined at a temperature of 550 °C and hydrophobized, as the most effective adsorbent. A comparative analysis of models of adsorption of Cu2+ ions on hydrophobized bentonite showed compliance of the adsorption process by to the Freundlich model (R2 = 0.978). A technological scheme of a local water purification station for a textile enterprise has been proposed, including a two-component adsorption filter loaded with bentonite, granulated, calcined at a temperature of 550 °C and hydrophobized.