| Title |
Transformation of Solids in the Intermittent Aerobic Sludae Diaestion |
| Authors |
김성홍(Seong Hong Kim), 정태학(Tai Hak Chung) |
| Abstract |
Batch digestion of biological sludge by the intermittent aeration was carried out in this study. Reduction of pH and alkalinity in the intermittent aeration was smaller than the continuous aeration because of alkalinity production by denitrification in the intermittent aeration. Both VSS and FSS were reduced as digestion continued because FSS was released along with VSS destruction. Correlation between SS reduction and TCOD removal was high, and SS rather than VSS could be used as a useful index for aerobic and intermittent aerobic digestion of biological sludge. It was also found that the decay constant increased and the nonbiodegradable fraction decreased along with increasing aeration ratio. An empirical equation describing the SS removal efficiency as a function of the aeration ratio and digestion time was proposed. Soluble fraction of TCOD was negligibly small. Rapid increase of SCOD was observed in the initial period, however, SCOD gradually decreased as digestion continued because of decreased organic leaching and increased utilization of not easily degradable organics. |