Abgeschlossene Arbeiten seit 2004
Nutzen Sie die Recherchemöglichkieten im Forschungsinformationssystem (FIS) zur weiteren Einschränkung der aufgelisteten Abschlussarbeiten.
Test and evaluation of a pilot plant for photocatalytic oxidation of wastewater organic compounds
Art der Abschlussarbeit
Master
Autoren
- Bruel Müller, Geórgia Aimée
Betreuer
- Prof. Dr. André Lerch
- M.Sc. Sibel Tas-Köhler
Weitere Betreuer
Dipl.-Ing. André Wufka (Fraunhofer Institute for Ceramic Technologies and Systems IKTS)
Abstract
Pharmaceutical, agrochemical, antibiotic and UV-filter compounds belong to the category of micropollutants of Contaminants of Emerging Concern. This topic is growing in importance within the scientific community mostly because of the unknown effects of the presence of these compounds in the environment. These compounds are present in concentrations up to μg/L, such as carbamazepine (CBZ), that is used as a model persistent substance for degradation tests. Water treatment technologies are improving to attend these environmental challenges and photocatalysis is a promising method to be applied in this field. Involving the use of semiconductor materials and UV light, photocatalysis produces oxidative species that can degrade persistent micropollutants. In this study, two equipment, a single photocatalytic cell and a pilot plant consisting of three cells, were tested and evaluated regarding their photocatalytic performance and the factors affecting the degradations rates. Both were capable of degrading carbamazepine to >99% of its initial concentration in both synthetic wastewater and wastewater treatment plant effluent. Flow rate presented a major influence in kinetic coefficients. Operation in closed loop leads to higher degradation rates, although one-way flow can be employed depending on final water quality requirements. UV-C lamp presented less efficiency than VUV lamp, but VUV can produce toxic compounds out of initially present compounds in water and may not be suitable for drinking water. Treating WWTP effluent with photocatalysis, COD decayed up to 70% in the single cell after 380 minutes and in 80% after 240 minutes in the pilot plant. The process was also able to reduce TOC, colour, SAC parameters and other relevant micropollutants, such as Diclofenac, Ibuprofen, Naproxen, Sulfamethoxazol, Triclosan, DEET, Bisphenol A, and some UV-Filters (BP, BP-1, BP-3, BP-4) to > 99% in most of the cases. Presence of NaCl influenced negatively the degradation, while no advantage in using hydrogen peroxide was observed. Initial compound (main pollutant) concentration did not affect the efficacy of photocatalytic degradation. The foam without active binder and that was in the original state (not refurbished) presented the best degradation results. Energy use was more efficient when higher flow rates were applied. The degradation capacity for the single cell was 100.00 mg CBZ/kWh in synthetic wastewater and 176.99 mg COD/kWh in WWTP effluent, while for the pilot plant these values were 115.91 mg CBZ/kWh and 237.90 mg COD/kWh respectively. The energy consumption by pilot plant to treat CBZ or COD was more efficient than with the single cell.
Schlagwörter
photocatalysis, carbamazepine, WWTP effluent, micropollutants
Berichtsjahr
2020