On-line sensor monitoring for chemical contaminant attenuation during UV/H2O2 advanced oxidation process

• Published in: Water research (Oxford) 2015-09, Vol.81, p.250-260
• Main Authors: Yu, Hye-Weon, Anumol, Tarun, Park, Minkyu, Pepper, Ian, Scheideler, Jens, Snyder, Shane A.
• Format: Article
• Language: English
• Subjects: Attenuation; Degradation; Endocrine Disruptors - analysis; Endocrine Disruptors - chemistry; Environmental Monitoring - methods; Hydrogen Peroxide - chemistry; Indicator; Indicators; Monitoring; On-line sensor; On-line systems; Organic Chemicals - analysis; Organic Chemicals - chemistry; Oxidation; Oxidation-Reduction; Pesticides - analysis; Pharmaceutical Preparations - analysis; Pharmaceutical Preparations - chemistry; Photolysis; Sensors; Surrogate; Trace organic compound (TOrC); Ultraviolet Rays; UV/H2O2; Waste Disposal, Fluid - methods; Waste Water - chemistry; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - chemistry; Water Purification - methods; Water reuse
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2015.05.064

A combination of surrogate parameters and indicator compounds were measured to predict the removal efficiency of trace organic compounds (TOrCs) using low pressure (LP)-UV/H2O2 advanced oxidation process (AOP), engaged with online sensor-based monitoring system. Thirty-nine TOrCs were evaluated in two distinct secondary wastewater effluents in terms of estimated photochemical reactivity, as a function of the rate constants of UV direct photolysis (kUV) and hydroxyl radical (OH) oxidation (kOH). The selected eighteen TOrCs were classified into three groups that served as indicator compounds: Group 1 for photo-susceptible TOrCs but with minor degradation by OH oxidation (diclofenac, fluoxetine, iohexol, iopamidol, iopromide, simazine and sulfamethoxazole); Group 2 for TOrCs susceptible to both direct photolysis and OH oxidation (benzotriazole, diphenhydramine, ibuprofen, naproxen and sucralose); and Group 3 for photo-resistant TOrCs showing dominant degradation by OH oxidation (atenolol, carbamazepine, DEET, gemfibrozil, primidone and trimethoprim). The results indicate that TOC (optical-based measurement), UVA254 or UVT254 (UV absorbance or transmittance at 254 nm), and total fluorescence can all be used as suitable on-line organic surrogate parameters to predict the attenuation of TOrCs. Furthermore, the automated real-time monitoring via on-line surrogate sensors and equipped with the developed degradation profiles between sensor response and a group of TOrCs removal can provide a diagnostic tool for process control during advanced treatment of reclaimed waters. [Display omitted] •We study TOrCs attenuation and changes in surrogates during UV-AOP for water reuse.•TOrCs attenuation was categorized into 3 groups according to photochemical reactivity.•TOCoptical, UV absorbance, and fluorescence are good surrogates for TOrCs attenuation.•On-line real-time sensor monitoring can provide UV-AOP efficacy for TOrCs attenuation.