Two laboratory scale biological processes, a combined hydrodynamic cavitation–hydrogen peroxide process and UV treatment were tested for removal of ibuprofen, naproxen, ketoprofen, carbamazepine, diclofenac, and clofibric acid. Biological treatment was performed using suspended activated sludge and moving bed biofilm flow-through reactors, operating under identical conditions. The suspended activated sludge process showed poor and inconsistent removal of clofibric acid, carbamazepine and diclofenac, while ibuprofen, naproxen and ketoprofen yielded over 74% removal. Moving bed biofilm reactors resulted in higher removal of ibuprofen and diclofenac. For combination of hydrodynamic cavitation and hydrogen peroxide optimal parameters were established and removal efficiencies between 3–70% were achieved. Coupling the attached-growth biomass biological treatment, hydrodynamic cavitation/hydrogen peroxide process and UV treatment resulted in removal efficiencies of )90% for clofibric acid and )98% for carbamazepine and diclofenac. Remaining compounds were reduced to levels below the LOD. For ibuprofen, naproxen, ketoprofen and diclofenac the highest contribution to overall removal was attributed to biological treatment, for clofibric acid UV treatment was the most efficient, while for carbamazepine hydrodynamic cavitation/hydrogen peroxide process and UV treatment were equally efficient.
COBISS.SI-ID: 26582055
Nowadays, due to lack of freshwater resources a sufficient wastewater management is an environmental concern. This global issue is resulting in the rapid growth of technologies for wastewater treatment. In this study a novel rotation generator of hydrodynamic cavitation is presented, which is used as a tool for pharmaceuticals removal in water. On presented machine analysis of hydrodynamics is made, where the extent and aggressiveness of cavitation is evaluated. The study has shown, that for a sufficient treatment, hydrodynamic cavitation with combination of hydrogen peroxide is needed. The removal of four pharmaceuticals (ibuprofen, ketoprofen, carbamazepine and diclofenac) was considered, where the over 80% effect was achieved. Various operating parameters such as the rotors geometry of the cavitation generator, pressure in the treatment chamber, temperature of the liquid, amount of hydrogen peroxide and time of exposure to the cavitation was investigated. The experimental results show that hydrodynamic cavitation has a good potential for efficient removal of pharmaceuticals what suggests to continue with research in this field and to consider an appropriate design for a commercial use.
COBISS.SI-ID: 13049115
Treatment performance and fish production were evaluated in a small-scale cyprinid fish farm with a closed-loop system consisting of a 0.2 m³ experimental fish tank (Tank A) with initial carp load of 1 kg/m³ and of a treatment train (TT) with a vertical constructed wetland (CW) and an ultrasonic unit (US). Tank A with average water circulation of 60 L/h was compared with a control tank (Tank B) of the same dimensions and fish load but with no TT. The experiment was divided into three sequential trials using different combinations of CW media and US. A preliminary trial was performed for evaluation of US efficiency in algae control. The results showed that the system with CW filled with sand performed better for chemical oxygen demand, ammonium nitrogen, total phosphorous and orto-phosphate, while the system with CW filled with expanded clay performed better for biochemical oxygen demand, nitrate-nitrogen and nitrite-nitrogen. There were no differences in total suspended solids between both systems. Specific growth rates and the fish body weight increase in Tank A were higher than in Tank B. In the third trial, the values of the above-listed parameters in Tank A were higher than in the first two trials due to an accumulation of nutrients in Tank A. US reduced algae biomass in free water by 63%.
COBISS.SI-ID: 4625003