Abstract
Phenol removal capability of channel flow process was studied. It was shown experimentally that channel flow process could remove phenol perfectly under volqmetric phenol loading rate below 17mg/l·day. The reaeration coefficients at joint part of water channel were determined experimentally. By taking the oxygen balance, which incorporates surface reaeration, reaeration at joint part and influent DO concentration, the oxygen supplyed by algae (biogenic oxygen) was revealed to play an important role in phenol removal. The amount of attached sludge on string type contactor decreased under conditions in which phenol remained in water channel, but the amount of attached sludge on channel wall increase steadily during experiments. Observed sludge yield (Yob) was determined to be 0.270g-MLSS/g-TOC based on the estimated amounts of attached sludge at the end of experiments. The specific microorganisms for phenolic wastewater treatment by channel flow process were Beggiatoa and Oscillatoria. The accumulation of agar-like substances was recognized in first water channel in which Beggiatoa dominated. The protozoa diversity in water channel was decreased with increase of volumetric phenol loading rate.
