In this study, ultrasound was employed to remove color and chemical oxygen demand (COD) from baker's yeast effluent. An ultrasonic homogenizator with 20kHz frequency was used for this purpose. The effect of operational parameters such as ultrasonic power, pulsed cycle, volume of wastewater and dilution ratio (wastewater volume/distilled water volume) was investigated. It was observed that decolorization increased with increasing ultrasonic power and with decreasing wastewater volume. The results show that there was no significant effect of pulsed cycle and an optimum dilution ratio was ¼ on decolorization of baker's yeast effluent. There was no change on COD value at the studied conditions. Keywords: baker's yeast effluent, chemical oxygen demand, decolorization, ultrasoundMaya endüstrisi atıksuyunun ultrasonik arıtılmasında işletme parametrelerinin etkisi ÖZ Bu çalışmada, maya endüstrisi atıksuyunun renk ve kimyasal oksijen ihtiyacı (KOİ) giderimi için ultrases kullanılmıştır. Bu amaçla 20kHz frekansta ultrasonik homojenizatör kullanılmıştır. Ultrasonik güç, vuruş döngüsü, atıksu hacmi, seyreltme oranı (atıksu hacmi/distile su hacmi) gibi parametreler incelenmiştir. Renk gideriminin ultrasonik güç artarken ve atıksu hacmi azalırken arttığı gözlenmiştir. Sonuçlar maya endüstrisi atıksuyunun renk gideriminde vuruş döngüsünün önemli etkisinin olmadığını göstermiştir. Renk gideriminde optimum seyreltme oranı ¼'dür. Çalışılan koşullarda KOİ değerlerinde değişiklik olmamıştır.

In this study, ultrasonic treatment of baker’s yeast effluent was investigated in an ultrasonic homogenizer emitting waves at 20 kHz. The SnO2/TiO2 composites were used as a sonocatalyst to assist the sonication process. Decolorization and chemical oxygen demand (COD) removal of baker’s yeast effluent with ultrasonic irradiation was examined. The effect of the composite preparation method, the molar ratio of SnO2/TiO2, mixing time while the composite was prepared, the calcination temperature and time, the catalyst amount were investigated. The decolorization was higher at a 4:1 molar ratio of the SnO2/TiO2 composite prepared by using an ultrasonic probe and 6 min ultrasonic irradiation time. The decolorization increased, with an increase in the calcination temperature. The optimum calcination time was 60 min and catalyst amount was 0.2 g/l. According to the results, decolorization rate was 26.63% using this composite. There was no COD removal at the studied conditions.