The biological degradation of phenol and 2-chlorophenol was studied at room temperature in a microprocesser controlled fill-and-draw reactor using activated sludge from the Passaic Valley Sewerage Commissioners wastewater treatment plant (Newark, New Jersey). The reactor was cycled through four unit processes: fill, react, settle, and draw. Different cycle times were tested, and the system response was characterized by dissolved oxygen measurements and substrate analysis (by gas chromatography).
With inhibitory substrates, such as those tested, this reactor had much more flexibility, and was therefore much easier to operate, than a standard continuous flow reactor
