# Rationale for the Combined Use of Biological Processes and AOPs in Wastewater Treatment Tasks
## 3 Results and Discussion
### Modeling the Effects of Antibiotics and Surfactants on the Activity of Bioprocesses
\begin{table}
\begin{tabular}{l l} \hline \hline \multicolumn{3}{c}{**Disadvantages of Physical (Mechanical) Methods**} \\ \hline - & Possibility of creation, as a result of partial clogging of filtering elements, of bacterial colonies on operating water treatment facilities (filters); - & Accumulation of filtered masses harmful to both people and the environment (filters, centrifuges, settling tanks, hydrocyclones); - & Exclusively continuous flow-through operation (filters, centrifuges, hydrocyclones); - & Destruction only of viruses, microbes, and bacteria themselves, and not of their more harmful products (ultrasound, irradiation, ozonation); - & Destruction of useful (necessary for humans) microflora (ultrasound, ozonation, irradiation); - & Limited afterefect and penetration at high concentrations of pollutant (ozonation, irradiation, ultrasound). \\ \hline \hline \multicolumn{3}{c}{**Disadvantages of Chemical Methods**} \\ \hline - & The possible formation of new compounds as a result of chemical reactions that are more harmful to humans and the environment than the original pollutants (all methods); - & Accumulation of a large volume of harmful “used reagent + pollutant” complexes (coagulation, flocculation); - & Destruction of useful microflora (chlorination); - & Presence of a reagent farm, which is itself a pollutant (all methods). \\ \hline \multicolumn{3}{c}{**Disadvantages of Biological Methods**} \\ \hline - & High requirements for compliance with technological and regime parameters of & bioprocesses (temperature, pressure, ORP, incoming water composition, frequency of & additional nutrients, hydraulic retention time of activated sludge); significant energy costs & or possible deterioration of treatment efficiency (all methods); - & Low level of adaptation to the existing “salvo” releases of chemically active harmful & \\ - & Greater complexity and cost of intensification (acceleration) of purification processes & (vermiculture, biological ponds). \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Types of technological disadvantages according to different methods of wastewater treatment. disadvantages, so the introduction of advanced oxidative processes in the practice of water treatment together with other methods also seems very relevant. The basic advantage of biological treatment methods is their environmental friendliness and safety for the natural components of the environment. Difficulties manifest themselves in the stabilization and formation of an equilibrium system between the processes of decomposition of complex organic impurities and preservation of the constancy of the biomass of the necessary ecological and trophic groups of microorganisms. It is important to stimulate the development of the desired dominant species composition of activated sludge, increasing their metabolic activity, which is possible with the use of physical and chemical methods of activation of biological processes [36]. Inhibitors of biological processes used in wastewater treatment plants, which can be eliminated by using AOPs, can include the entry of surfactants and antibiotics with effluents. Thus, surfactants impair the sedimentation of wastewater and inhibit oxygen transport to the cells of activated sludge microorganisms in aeration tanks. Increasing concentrations of antibiotics in wastewater submitted for treatment inhibits the growth of activated sludge microorganisms; under anaerobic conditions, the productivity of the biosystem falls, biogas yield decreases, and incomplete denitrification with an increase in residual pollution occurs. This also affects the composition of the sewage sludge from the wastewater treatment plant, which is further stockpiled on sludge cards, and is not utilized due to increased pollutant contamination [36; 38].