Standard reporting of Electrical Energy per Order (E _EO) for UV/H₂O₂ reactors (IUPAC Technical Report)

Abstract

The concept of Electrical Energy per Order (EEO) was introduced in 2001 as a figure of merit for evaluating the energy requirements of ultraviolet-based advanced oxidation processes (UV AOPs) used for the degradation of various organic contaminants. The EEO parameter represents the energy input into the reactor that can achieve an order of magnitude decrease in the concentration of a target contaminant in a unit volume. Since the introduction of this parameter, it has become increasingly popular among UV AOP researchers and practitioners. However, the EEO is often reported without important details that affect the parameter, making its interpretation difficult. The EEO depends on a variety of factors (e.g. the concentration and identity of the target contaminant and the amount of hydrogen peroxide added). Therefore, the EEO parameter needs to be reported in the literature with several other experimental details affecting the reactor performance and in a way that proper comparisons can be made between reactors across studies or manufacturers. This paper discusses the proper application of the EEO parameter for bench-, pilot-, and full-scale studies. Sucralose (artificial sweetener, C12H19Cl3O8) is proposed as a standard substance for reactor comparison.

Kinetics of Microcystin-LR Removal in a Real Lake Water by UV/H2O2 Treatment and Analysis of Specific Energy Consumption

“…When the concentration of the contaminant is very low, the amount of electric energy required to reduce the contaminant concentration by one order of magnitude can be considered independent of the initial concentration [ 46 , 53 ]. The water depth and the distance between the lamp and the water surface could affect the order of magnitude of the removal [ 46 ].…”

“…When the concentration of the contaminant is very low, the amount of electric energy required to reduce the contaminant concentration by one order of magnitude can be considered independent of the initial concentration [ 46 , 53 ]. The water depth and the distance between the lamp and the water surface could affect the order of magnitude of the removal [ 46 ]. Although the lamp was not submerged into the reactor, in this work these two effects were neglected considering: (i) the low level of water inside the reactor and (ii) the presence of the black lampshade that avoided the dispersion of UV rays conveying them onto the reactor.…”

“…Although the lamp was not submerged into the reactor, in this work these two effects were neglected considering: (i) the low level of water inside the reactor and (ii) the presence of the black lampshade that avoided the dispersion of UV rays conveying them onto the reactor. Therefore, the energy consumption of the UV system was evaluated following the kinetic model of the electrical energy per order (E EO ) according to Equation (4) [ 46 , 54 , 55 ]: E EO,UV = (P × t × 10 3 ) × (V × log 10 (C 0 C −1 )) −1 where P is the nominal power (kW) of the system, t (h) is the processing time and V (L) is the volume of water. The nominal power (P) was assumed equal to the energy input to the system, considering a fluence rate of 0.2 mW cm −2 and assuming a UV-C production yield of the lamp equal to 35%.…”

Towards Scaling-up Photocatalytic Process for Multiphase Environmental Applications: A Review

“…The economic sustainability of photocatalytic wastewater treatment on large scale is generally discussed in terms of electrical energy per order (EÉO) values [76,77]. While several advance oxidation processes, including ozonation, UV/H2O2, UV/persulfate, and UV/chlorine present median EEO values < 1 kWh/m 3 , hence are considered competitive for drinking water applications, the EEO for photocatalysis with UV activation are generally > 10-100 kWh/m 3 [78,79].…”

Enhanced UV Direct Photolysis And UV/H2O2 For Oxidation of Triclosan And Ibuprofen In Synthetic Effluent: An Experimental Study

“…The EEO is a parameter used to evaluate the amount of energy required for the decay of the target contaminant concentration by order of magnitude a 90% reduction in 1 m³ of water (Keen et al 2018). The figure of merit was calculated according to Bolton et al (2001) and is represented using Eq.…”