Ahmad Azari

Wastewater pollution has become a global concern. Among the various methods of wastewater treatment, adsorption has been highly regarded by researchers. In this research, one-stage and multi-stage fixed-bed adsorption columns have been modeled and simulated. For this purpose, experimental data of oil adsorption isotherms on natural zeolite and calcined bentonite were estimated. Then, by assuming a linear driving force for the adsorption kinetics, the governing equations were discretized by the incremental differential quadrature method. The results showed that natural zeolite has a better performance for oil effluent treatment. Also, in the fixed bed adsorption column, better separation was performed by decreasing the flow rate, inlet concentration and increasing the bed height. The performance of the multi-stage adsorption column in the different connection and the number of bed was investigated, which showed the best performance of the series connection. Also, in series and series-parallel connection, with increasing the number of beds, the output concentration decreases significantly. Finally, the adsorbent mass were optimized in different flow rates, the number of beds and inlet concentrations, which showed that in systems with more than two beds, the required adsorbent mass decreases with increasing the number of beds and decreasing the flow rate and inlet concentration.