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(caffeine, sulfamethoxazole, benzotriazole, Among the processes developed for the re-
roxithromycin and erythromycin). In contrast, moval of micropollutants, we can now find
a further increase to 8 gTSS-L resulted in only several under full-scele evidences. According
-1
a slight improvement in removal, indicating to our knowledge so far, the treatment of bio-
that the rate was not proportional to the logically treated wastewater with ozonation and
biomass concentration. The flake size varies subsequent filtration (in a sand filter, possibly
between 10 and 100 µm in the membrane using a membrane) can be considered effective.
bioreactor system (MBR) and between 100 Ozonation has been used in drinking water
and 500 µm in the classical activated sludge purification for a long time in water technology,
system. Substrate delivery to the bacteria due to which sufficient amount of experien-
is by diffusion due to the small size of the ce has been accumulated in the operation of
microorganisms and the large surface area ozone treatment, which can be classified as
of the flake, which provides a short distance one of the advantages of this oxidation process.
for nutrient penetration, so the advantage of Ozonation, which provides high-efficiency
the MBR system is clear. oxidation, can be supplemented with the use
• By evaluating the effect of pH, it can be of UV or H O , which undoubtedly increases
2 2
concluded that drugs exist in different proton the investment and operating costs of a more
uptake states in the aquatic environment complex treatment system.
depending on the pH. The pH affects the
removal of micropollutants. Nitrification Activated carbon adsorption - similarly to drin-
shifts the pH significantly in the acidic di- king water purification systems - can also be
rection, so that for ibuprofen, for example, a suitable method for removing micropollutants
removal can be as high as 90% at pH less from wastewater. Activated carbon in pow-
than 6. In sludge treatment, the pH can rise der or granulated form is capable of removing
above 9, in which case desorption of mic- pollutants through surface binding. Powdered
ropollutants takes place. The compounds activated carbon into the activated sludge basin
are removed from the solid phase into the or, after that, into a separate contact reactor
aqueous phase. (dosed together with a coagulant, and remo-
ving the solid state materials by sedimentation
Generally, the organic micropollutants are or filtration) is a proven effective process. Of
only removed with a low efficiency with the course, the activated carbon process can also
help of conventional biological wastewater be combined with ozonation. After ozonation,
treatment systems. The sludge age, the sludge instead of sand filtration, it can even be used as
concentration, the hydraulic residence time of an activated carbon GAC adsorbent to increase
the wastewater, or the pH and temperature of the pollutant removal efficiency, which, howe-
the wastewater all affect the removal efficiency. ver, already results in a substantial increase in
By controlling pH, MLSS, SRT or HRT, we can operating costs. The disadvantages of activated
achieve a small increase in the efficiency of carbon include its high cost, the necessary
a working plant, but the possibility of modifíing regeneration, and the difficulties associated
these parameters is limited. with the disposal of the sludge.

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