| Simulated wastewater samples containing antifreeze were treated biologically using a packed column as an aerator. The objective of this project is to determine the rate of biological degradation of ethylene glycol at different air flow rates, liquid flow rates, and varied seeding rates at different time intervals, to achieve the highest removal rate of the BOD. The biological oxygen demand (BOD) of the wastewater was measured. Under a liquid flowrate of 5.5 kgm -2s-1 the BOD removal increased when the air flowrate was increased from 0.0069 to 0.0414 kgm-2s-1. However, further increases of the air flowrate beyond 0.0138 kgm-2 s-1 did not affect the BOD removal rate significantly. On the other hand, with a constant air flowrate when the liquid flowrate was increased from 5.5 to 11, 16.5, and 27.5 kgm-2s-1, the percent BOD removal appeared to decrease slightly. It was also found that the increase in amount of seeding has no significant effect on BOD removal. The averaged BOD removal of about 90% was obtained after 72 hours of the wastewater treatment. |
