Contact-Adsorption-Regeneration-Stabilization Process for the Treatment of Municipal Wastewater

Abstract

In this work, the application of the contact-adsorption-regeneration-stabilization activated sludge process for the municipal wastewater treatment was investigated by using continuous experiments coupled with adsorption batch experiments. The process optimization for performance evaluation was studied. The obtained appropriate operational parameters of recycle ratio, hydraulic retention time (HRT) of the regeneration tank, HRT of the adsorption tank and solids retention time (SRT) of the system were 40%, 2 h, 30 min, and 6 d, respectively. Adsorptive kinetics and equilibrium were investigated with batch experiments of adsorption. The results showed that the activated sludge concentration was in a positive proportion to its adsorptive capability, but that temperature was in an inverse proportion to the adsorptive capability. Adsorptive equilibrium was reached within 15 min. In addition, the equilibrium data fitted well to both the Freundlich and Langmuir adsorption models.