The utility model belongs to the field of
sewage treatment, and particularly relates to a circulation type biological contact oxidation reactor which comprises a growth reaction area, a transition cone area is fixedly installed at the bottom of the growth reaction area, a U-shaped connecting area is fixedly installed at the bottom of the transition cone area, and a
backflow area is fixedly installed at the end, away from the transition cone area, of the U-shaped connecting area. A straight channel area is fixedly mounted on the outer wall of the
backflow area, a lifting
assembly is arranged on the outer wall of the growth reaction area, a mounting
sieve plate is arranged on the lifting
assembly, and a
bed frame
assembly is arranged on the mounting
sieve plate. According to the circulation type biological contact oxidation reactor, by arranging the lifting assembly and the
special bed frame
assembly structure, when the
bed body needs to be replaced, the
bed frame assembly can leave the growth reaction area only by starting the electric cylinder base, then limiting on the mounting disc is relieved through simple operation, and the mounting disc can be conveniently taken down to replace the bed body; the replacement time is obviously shortened, and the maintenance efficiency is improved.