Treatment of wastewater from the textile factory Galeb d. d. with sequence batch reactor and pretreatment with Fenton oxidation

Glavni cilj naloge je bil obdelati surovo odpadno vodo hrvaškega tekstilnega podjetja Galeb d. d. s šaržnim biološkim reaktorjem (ang. Sequence Batch Reactor (SBR)) do te mere, da bodo zadoščeni kriteriji zapisani v obratovalnem dovoljenju podjetja. Proces čiščenja s šaržnim biološkim reaktorjem smo izbrali zaradi cenovne ugodnosti, nezahtevnosti procesa in neuporabe kemikalij v procesu čiščenja. Proces čiščenja odpadne vode v šaržnem bioreaktorju je identičen procesu samočiščenja, ki poteka v naravi, s to razliko, da poteka hitreje zaradi velike koncentracije mikroorganizmov v aktivnem blatu. Analize vzorcev surove in prečiščene odpadne vode smo opravljali na Fakulteti za kemijo in kemijsko tehnologijo Univerze v Mariboru in v Nacionalnem laboratoriju za zdravje, okolje in hrano (NZLOH) v Mariboru. Od podjetja Galeb d. d. smo pridobili šest vzorcev surove odpadne vode, ki smo jih v petih procesih čistili le v šaržnem bioreaktorju, v šestem procesu pa smo testno izvedli še predobdelavo s Fentonovo oksidacijo, ki ji je sledil standardni postopek čiščenja v SBR. Za predobdelavo odpadne vode smo se odločili predvsem zaradi želje po zmanjšanju obarvanosti prečiščene odpadne vode. Od enajstih parametrov, ki so presegali maksimalno dovoljeno koncentracijo (MKD), določeno z obratovalnim dovoljenjem podjetja, smo jih s procesom čiščenja v SBR uspeli zmanjšati šest. V šestem procesu, kjer smo odpadno vodo pred vstopom v SBR obdelali s Fentonovo oksidacijo, nam je v povprečju uspelo zmanjšati vrednost spektralnega absorpcijskega koeficienta (SAK) na zadanih valovnih dolžinah kar za 96,89 %. Prav tako se je predobdelava s Fentonovo oksidacijo izkazala kot učinkovito pri zmanjševanju kemijske potrebe po kisiku (KPK), ki je bila v vseh iztokih iz SBR pod MDK.The main objective of the project was to process the raw wastewater of the Croatian textile company Galeb d. d. with the Sequence Batch Reactor (SBR), the criteria was recorded in the company\u27s operating license. The purification process with the SBR was chosen because of the convenient price, the smoothness of the process and the non-use of chemicals in the cleaning process. The process of purification of wastewater in a sequence batch bioreactor is identical to the process of self-cleaning in nature, with the difference that it is faster because of the high concentration of microorganisms in the active mud. We analyzed the samples of raw and purified wastewater, which we carried out at the Faculty of Chemistry and Chemical Technology, University of Maribor, and in the National Laboratory for Health, Environment in Food, Maribor (NZLOH). From Galeb d. d. we obtained six samples of raw wastewater, which were purified in five processes in the sequence batch bioreactor. In the sixth process, we also tested Fenton oxidation pre-treatment followed by a standard cleaning process in SBR. For pre-treatment of wastewater, we decided mainly because of the desire to reduce the coloring of purified wastewater. We managed to significally lower six out of eleven parameters that exceeded the maximum allowable concentration to the extend of acceptable concentration in textille wastewater. In the sixth process, where wastewater was treated with Fenton oxidation before entering the SBR, we managed to reduce the value of the spectral absorption coefficient at the given wavelengths by 96.89% on average. Fenton oxidation treatment also proved to be effective in reducing chemical oxygen demand (COD), which was in all outflows from SBR under maximal allowable concentration