Model-based scenario analysis to support the operation of solar photo-Fenton plants

Model-based tools applied to wastewater management have been identified as an emerging solution to address the associated challenges related to the optimization of the technologies, meeting more restricted water quality standards. Thus, for the first time, the demonstration of the solar photo-Fenton process for microcontaminant removal in the operating environment of a model-based tool is reported. This tool aids in determining the right cost-effective seasonal strategy for a 37-m² demonstration-scale photoreactor operating in a rural wastewater treatment plant. It was developed using a model tuned adequately with experimental data obtained at lab scale and then validated in the solar photo-Fenton demonstration plant, proving its reliability, and enveloping a robust operation. Imidacloprid removal was the treatment target, and reagent concentrations were 0.1 mM for ferric nitrilotriacetate and 0.73 mM for hydrogen peroxide. According to the model-based tool, to attain the maximum treatment capacity, the best operating conditions were a liquid depth of 20-cm, and hydraulic residence time of 45 and 60-min in summer and winter, respectively, augmenting the treatment cost by 25% (0.49 €∙m^-3 vs. 0.65 €∙m^-3). This model-based tool allows the control and optimization of the technology to be improved, while promoting its attractiveness in the market.