An improved hybrid strategy for online dosage of hydrogen peroxide in photo-Fenton processes

Regulation of Hydrogen Peroxide Dosage in a Heterogeneous Photo-Fenton Process

“…Nevertheless, among operational photo-Fenton process conditions, the H 2 O 2 concentration present at each time is perhaps the most important parameter in the HPP affecting both the reaction outcome and the cost of the process [23]. If an equivalent amount of H 2 O 2 is added at the beginning of the reaction, the process could not reach total contaminant degradation.…”

“…In the online DO measurement mode, the second one is to use this measurement as an output variable in applying an automatic closed-loop control law. This last task carries out the dosing of input H 2 O 2 to optimize its consumption, as well as other reagents into the reactor, which allows reaching better degradation results [23,24].…”

“…Several researchers have reported a continuous dosage of H 2 O 2 using DO as control variable [23,24]. To the best of our knowledge, no works upon (i) the treatment of more complex wastewater, (ii) modeling and control heterogeneous photo-Fenton processes without pH adjustment at the same time has been reported.…”

Towards an Efficient Generalization of the Online Dosage of Hydrogen Peroxide in Photo-Fenton Process to Treat Industrial Wastewater

“…In this context, the sequential addition of H 2 O 2 along the reaction span has been reported to enhance mineralization [ 10 , 11 ], furthermore, continuous automatic dosage has also been studied, with positive results [ 12 ]. However, the determination of an adequate dosage cannot be limited to a pre-fixed recipe (open-loop control), but it should ideally consider some process feed-back (closed-loop control) to adapt to process disturbances and or model mismatch in a robust way [ 13 ]. It is important to stress that the H 2 O 2 dosage strategy is extremely significant for photo-Fenton process competitiveness because the H 2 O 2 is the most expensive reagent; consequently, reducing its consumption is key to reducing its operation cost [ 14 ].…”

“…Different variables, such as Redox potential [ 15 ], have been explored; nevertheless, dissolved oxygen (DO) has demonstrated to be efficient and useful, as well as conceptually consistent with the kinetic model (Reaction 6) [ 16 ]. Recently, it was reported that the use of the derivative of the online DO measurement allows providing a significant improvement in process performance [ 13 ]. The proposed H 2 O 2 dosage methodology consists of a hybrid strategy including an initial single H 2 O 2 addition (open-loop) followed by a continuous addition until an appropriate DO level is attained.…”