Treatment of wastewater from bottling fruit juices with membrane processes

Otpadna voda punionice voćnih sokova pročišćavana je membranskim bioreaktorom s uronjenom membranom (MBR), nanofiltracijom i ozoniranjem. Praćen je rad MBR-a kroz 19 radnih dana. Membranskim bioreaktorom učinkovito je obrađena otpadna voda (90%) pri niskim koncentracijama KPK, ali pri visokim koncentracijama organske tvari u ulaznoj vodi učinak uklanjanja je bio 58% što možemo objasniti preniskom koncentracijom biomase (MLSS≈4g/L ), premalim vremenom zadržavanja, preniskom koncentracijom kisika, čestim povišenim vrijednostima pH ulazne vode, niskom temperaturom, te relativno visokom provodljivosti. Pri mnogo dužem vremenu zadržavanja učinkovitost uklanjanja opterećene otpadne vode (KPK=3560mgO2/L) bila je 85%, što ukazuje da je razgradnja moguća samo je upitna brzina razgradnje. Nanofiltracijom vode prethodno pročišćene membranskim bioreaktorom postignuta je vrlo visoka učinkovitost uklanjanja organske tvari (KPK=97,8%, TOC=99,2%). Ozoniranje je provođeno kroz 72 sata uz uklanjanje organske tvari izražene kao KPK od samo 3%. Budući da doza ozona nije bila poznata trebalo bi pokus ponoviti s većim dozama.Wastewater from bottling fruit juices was purified with membrane bioreactor with immersed membrane (MBR), nanofiltration and ozonation. Work of MBR was studied for 19 days, from the presented results efficiency of removing organic compounds is established (90%) at low concentration COD, but at high concentration of organic compounds efficiency of removing was 58%. We can explain that with too low concentration of biomass (MLSS=4g/L), short time of retaining, too small concentration of oxygen, pH was often too high, low temperature and relatively high electrical conductivity. At much longer time of retaining, efficiency of removing bad wastewater was 85%, it can be concluded that wastewater is extractable; it is only mater of time. With nanofiltration of water treated with MBR, high efficiency of removing organic compounds is established (COD=97,8%, TOC=99,2%). Ozonation was studied for 72 hours, efficiency of removing organic compounds was very low, COD=3%. This process should be repeated with higher doses, because the dose of ozone wasn’t familiar