Remi NAKAMURA

Anaerobic Treatment of a Shochu Distillery Wastewater by a Multi-Staged Thermophilic UASB Reactor

Hideki HARADA, Akiyoshi OHASHI


In the Kyushu, 480,000t/year of Shochu distillery wastewater discharged of 30% is dumping into the ocean which strictly prohibition according to London Convention. We selected the thermophilic Multi-Staged UASB reactor for this study. It is necessary to add the alkali chemicals too much because pH was decrease in the waste water inlet port of a UASB reactor. Effluent water contains the alkalinity generated within the reactor. Therefore, we selected effluent recycling and try the alkali agent addition cost cut.

As a result, without effluent recycling adds alkalinity 0.3 gNaHCO3/gCOD, the reactor allowed 30 kg COD/m3/d with keeping COD removal of above 80% and VFA concentration in effluent of 200�`500 mgCOD/L. In a period effluent recycling add alkalinity 0.15gNaHCO3/gCOD and 0.05gNaHCO3/gCOD, the reactor performed satisfactory keeping COD removal of above 88% and VFA concentration in effluent of around 200 mgCOD/L. In a period of effluent recycling eventually exhibited stable reactor performance with add alkalinity only 0.05 from 0.3 gNaHCO3/gCOD. Accordingly, alkali agent addition cost was also reducible to 1/6.