## 3 Applications and Limits of ATPs in Water and Wastewater Treatment
### Energy Demand and Cost-Effectiveness of ATPs
As an example, Table 10 reports the calculated EE/O values for the decomposition of antibiotics (sulfamethazole and chlorotetracycline) and other contaminants by different ATPs [105; 104]. Lower values indicate higher treatment efficiency. A study examining different wastewaters, two textile and one municipal effluent, evaluated different treatment options (primary and activated sludge, low-dose EB, and chlorination) to establish the reliability and optimum conditions for different treatment processes. EB was used for disinfection (municipal effluent) and treatment (textile effluent). The evidence of the study indicated that as far as cost estimates, EB at doses between 1 and 3 kGy compared to conventional methods was less expensive than activated sludge for treatment (but more expensive than chlorination for disinfection, as also shown in Figure 4) [97]. As noted earlier, the appropriate combination of different conventional (e.g., biological) and advanced processes (e.g., EB and O\({}_{3}\)) may result in more efficient and economic treatment of specific pollutants. [PERSON] et al. conducted a pilot study on the treatment of landfill leachate containing significant concentrations of recalcitrant organic substances with a scheme consisting of an activated sludge pre-treatment combined with the Fenton process and biological post-oxidation. The results indicated that the combined treatment according to the suggested scheme proved more efficient, both in efficacy and cost, than individual biological or chemical processes [106]. [PERSON] et al. compared pilot plant results obtained by combined EB and ozone treatment and conventional (biological plus disinfection) treatment of municipal wastewater from the town of Raduzhnyi (Russia). The combined EB+O\({}_{3}\) treatment cost was estimated at 17-30% of the cost of conventional treatment, depending on the influent COD concentration, to achieve comparable effluent quality [107]. Other authors compared the cost of using EB and \(\gamma\) radiation under different conditions. In general, the cost of running an EB unit was estimated at approximately half of that of a \(\gamma\) unit, and up to 60% lower than that of conventional technology [108]. A comparative treatment study of low (COD = 11,940 mg/L) and high (COD = 52,856 mg/L) real pharmaceutical wastewater indicated a treatment cost of EB \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Contaminant** & **EB** & **Ozonation** & **UV (210 nm) + H\({}_{2}\)O\({}_{2}\)** & **UV + TiO\({}_{2}\)** \\ \hline Chlortetracycline & 0.19 & 7.15 & 15.5 & \\ Methylene Blue & 0.6 & & 0.63 & 16.4 \\ Phenol & 1.5 & & 3.6 & 336 \\ Sulfamethazole & 0.46 & 27.53 & 1.5 & \\ Other pollutants (typical values) & \textless{}3 & & \textless{}3 & \textgreater{}50 \\ \hline \hline \end{tabular}
\end{table} 
Table 10: EE/O values for the decomposition of solute contaminants by different ATPs. radiolysis at 0.50 US$/m\({}^{3}\), activated sludge treatment at 2.35 US$/m, and EB/biological combination at 2.85 US$/m\({}^{3}\) for low-strength wastewater, whereas for the high-strength effluent, costs were 0.67, 0.7, and 1.37 US$/m\({}^{3}\), respectively. Activated sludge HRT was 2 days, and the EB treatment contact time was 3 and 4 min, respectively, for low- and high-strength wastewater but decreased to 2 and 1 min, respectively, with the addition of H\({}_{2}\)O\({}_{2}\) to the process. Peroxide addition, however, increased the combined treatment cost to 7.87 and 11.48 US$/m\({}^{3}\), respectively, in the low- and high-strength cases [80].  
[PERSON] et al. compared the cost of effluent disinfection in a 1.5 MeV EB facility to that of a UV peroxidation process. The reported total operating cost of the latter was US$ 0.68/m\({}^{3}\), and the calculated costs for EB treatment (including capital amortization and running costs) ranged between US$ 0.66 and 0.066 depending on the applied treated flow (36-480 m\({}^{3}\)/h) [109]. It should be noted that the previous estimate was based on an EB installation cost of US$ 2.35 million (in 1998).