Author/Authors :
Onodera، T نويسنده Center for Regional Environmental Research , , Sase، S نويسنده Center for Regional Environmental Research , , Choeisai، P نويسنده Department of Environmental Engineering , , Yoochatchaval، W نويسنده Department of Environmental Engineering , , Sumino، H نويسنده Department of Civil Engineering , , Yamaguchi، T نويسنده Department of Civil and Environmental Engineering , , Ebie، Y نويسنده Center for Material Cycles and Waste Management Research , , Xu، K نويسنده Center for Material Cycles and Waste Management Research , , Tomioka، N نويسنده Center for Regional Environmental Research , , Mizuochi، M نويسنده Center for Regional Environmental Research , , Syutsubo، K نويسنده Center for Regional Environmental Research ,
Abstract :
A combination of an acidification reactor and an up-flow staged sludge bed (USSB) reactor was
applied to treatment of molasses wastewater. The USSB, equipped with three gas solid separators, was
selected because of superior organic removal by means of good retention of granular sludge. The combined
system was continuously operated at mesophilic (35°C) conditions for 600 days. The USSB achieved a high
organic removal rate of 37 kgCOD/m3 day (organic loading rate of 43 kgCOD/m3 day with 86.2% COD
removal). The USSB retained high sludge concentration of approximately 58 gVSS/L based on the reactor
volume. The retained granular sludge had good settle-ability with a sludge volume index (SVI) of 4 to 20 ml/
gSS. The retained sludge possessed a sufficient level of methanogenic activities for acetate (1.2 gCOD/gVSS
day) and for hydrogen (1.7 gCOD/gVSS day). Analysis of microbial community revealed that genus
Methanobacterium as hydrogen utilizing methanogen and order Methanosarcinales as acetate utilizing
methanogen were detected in the retained sludge of the USSB reactor. The superior performance of the USSB
was attributed to good retention of a large amount of granular sludge with high methanogenic activity
