## 3 Results
### Energetic Considerations
As indicated by data, NTP was generally more efficient than the other tested processes for each compound, comparable to UV/H\({}_{2}\)O\({}_{2}\) at peroxide dose of 10 mg/L. It is however significant that NTP does not use UV lamps (subject to maintenance and replacement) or expensive peroxide addition to generate oxidative species, therefore it could be considered a viable alternative to more common processes. Table 7 reports EEO values determined for different AOPs [37]. These figures are only indicative, as it should be remembered that these numbers measure the energy output of the process devices, and do not take into account their energy conversion efficiency, which may vary from 30 to 80%, nor the \"stored energy\" contained in added chemicals and catalysts. Table 8 summarizes reported total cost-of-treatment (CoT) estimates for AOP technologies applied to (municipal) wastewater disinfection (to below detection limits of pathogens). While specific cost of chlorination remains constant (the cost is essentially based on chemical cost), that of other technologies diminishes with increasing treated flow (due to initial fixed costs). Among the technologies examined (EB, O\({}_{3}\) and UV), EB is the one with the steepest cost decline with treated flow [44]. \begin{table}
\begin{tabular}{l c c c c} \hline \hline \multirow{2}{*}{**Contaminant**} & \multicolumn{2}{c}{**NTP a**} & \multirow{2}{*}{**UV b**} & \multirow{2}{*}{**UV/H\({}_{2}\)O\({}_{2}\) b,c**} & \multirow{2}{*}{**UV/TiO\({}_{2}\) b,d**} \\  & **Range (mean)** & & & \\ \hline Meprobamate & 2.1–5.3 (3.5) & 6.6 & 1.0 & 6.8 \\ Dilantin & 1.1–3.1 (2.0) & 2.1 & 1.0 & 3.1 \\ Primidone & 1.1–3.3 (2.2) & 3.7 & 0.3 & 3.9 \\ Carbamazepine & 0.3–1.2 (0.7) & 2.3 & 0.4 & 2.1 \\ Atenol & 0.4–1.7 (1.0) & 1.4 & 0.5 & 2.0 \\ Trimethoprim & 0.3–1.2 (0.7) & 0.8 & 0.4 & 1.5 \\ Atrazine & 2.2–6.3 (3.7) & 3.3 & 1.2 & 4.7 \\ \hline \hline \end{tabular}  
* For nine different scenarios with generators ranging from 0.6 to 2.6 kWh/m3 and frequency 500–800 Hz;
* 32 amalgam UV lamps, each rated at 12 mW/cm2, 38% conversion efficiency; c peroxide concentration 10 mg/L;
* TiO\({}_{2}\) concentration 500 mg/L.  
\end{table} 
Table 6: Specific EEO values for different AOPs applied to some contaminants of interest on the same water matrix (spiked Lake Mead surface water, kWh m\({}^{\text{-3}}\)order\({}^{\text{-1}}\)) (data from [34]). \begin{table}
\begin{tabular}{l c c} \hline \hline \multirow{2}{*}{**AOP Type**} & \multicolumn{2}{c}{**EEO Range**} & \multirow{2}{*}{**EEO Median Value**} \\  & [kWh m\({}^{\text{-3}}\) Order\({}^{\text{-1}}\)] & [kWh m\({}^{\text{-3}}\) Order\({}^{\text{-1}}\)] \\ \hline Ozonation & 0.07–0.3 & 0.15 \\ O\({}_{3}\)/H\({}_{2}\)O\({}_{2}\) & 0.1–1.5 & 0.2 \\ EB & 0.2–1 & 0.3 \\ UV/Cl & 0.2–0.7 & 0.4 \\ UV/persulfate & 0.2–1.1 & 0.67 \\ O\({}_{3}\)/UV & 0.25–1 & 0.7 \\ UV/H\({}_{2}\)O\({}_{2}\) & 0.3–1.2 & 0.75 \\ Photo-Fenton & 1.1–10 & 2.6 \\ Plasma (any) & 1.1–12 & 3.3 \\ e-AOPs & 10–70 & 38 \\ UV/catalyst & 150–450 & 335 \\ Microwave & 500–700 & 540 \\ Ultrasound & 800–8000 & 2600 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Summary of published EEO-values of different AOPs (range and median values). It should be noted that the EB process showed, at the same time, substantial improvements in effluent water due to efficient further degradation of organic load (on irradiation, residual organic matter in the effluent is subject to exposure to radicals' action in greater amounts than with other technologies). This may imply an advantage in case of effluent reuse for irrigation, as water will contain simpler molecular organic forms that could be more easily metabolized by native soil microflora during land distribution.