Ion exchange system for the final purification of olive mill wastewater: Performance of model vs. real effluent treatment

• Published in: Process safety and environmental protection Vol. 103; pp. 308 - 314
• Main Authors: Víctor-Ortega, M.D., Ochando-Pulido, J.M., Martínez-Ferez, A.
• Format: Journal Article
• Language: English
• Published: Rugby Elsevier B.V 01.09.2016; Elsevier Science Ltd
• Subjects: Amberlite (trademark); Computer simulation; Conductivity; Effluent treatment; Effluents; Environmental law; Evolution; Food industries wastewaters; Food processing industry wastes; Ion exchange; Irrigation efficiency; Irrigation water; Olive mill effluent; Oxidation; Oxidation process; Pollutants; Polymers; Process parameters; Purification; Resin dosage; Resins; Secondary treatment; Simulating media; Sodium; Wastewater pollution; Wastewater reclamation; Wastewater treatment; Water purification; Wastewater reclamation; Resin dosage; Olive mill effluent; Purification; Ion exchange; Simulating media
• ISSN: 0957-5820; 1744-3598
• DOI: 10.1016/j.psep.2016.02.004

•Ion exchange process was previously optimized with lab-made model OMW-2ST.•Equilibrium was reached in 10 and 20min for model and real OMW-2ST, respectively.•Breakthrough time was lower for real versus model OMW-2ST (120 vs. 147.5min).•Final treated olive mill wastewater fulfils irrigation legal requirements.•Model OMW-2ST is confirmed as good simulating media to reproduce IE processes. Olive mill wastewater (OMW) is a highly pollutant effluent which can be pretreated through an advanced oxidation process. OMW after this secondary treatment (OMW-2ST) presented high sodium and chloride concentrations, responsible for its high conductivity. In this context, two ion exchange (IE) resins were examined (Dowex Marathon C and Amberlite IRA-67) for final OMW-2ST purification. As this effluent is extremely seasonal and deteriorates within few days, the main parameters affecting IE process were previously optimized with lab-made model OMW-2ST. Then the optimum operating conditions were tested with real OMW-2ST. Evolution of conductivity was evaluated as a function of recirculation time to study the effect of resins disposition and resins dosages and compared with both OMW-2ST. Equilibrium was reached in 10 and 20min for model and real OMW-2ST, respectively. Furthermore, continuous mode experiments were carried out in to investigate the evolution of conductivity as a function of operating time. Breakthrough time was lower for real versus model OMW-2ST (120 vs. 147.5min). Minimum 10gL−1 resin dosage ensured 74% and 78% removal efficiencies, thus fulfilling irrigation water legal requirements and rending the production system cost-effective and environmentally respectful. Finally, model OMW-2ST is confirmed as good simulating media to reproduce IE processes.