SEWAGE TREATMENT APPARATUS CAPABLE OF ENSURING DESIGN HYDRAULIC RETENTION TIME OF EXISTING OXIDATION DITCH REACTOR

摘要

The present invention relates to a sewage treatment device capable of securing design hydraulic retention time of an existing oxidation ditch reactor. The sewage treatment device comprises: a first settling tank which removes light suspended solids among the sewage which has passed through a grit chamber by depositing the same; a biological reactor which treats the sewage which has passed through the first settling tank; and a final settling tank which removes a sludge generated while passing through the biological reactor by depositing the same, and returns a returning water including a part of the sludge to the biological reactor. The biological reactor includes an inflow tank, and a first and a second biological reactor. The inflow tank blends the inflow water flowed in by passing through the first settling tank, and the returning water returned from the final settling tank. The first reactor includes: an anoxic tank which is formed to limit the upper space by having a horizontal partition as a boundary, and treats the sewage blended in the inflow tank in the anoxic condition after receiving the same; an anaerobic tank which is formed to limit the lower space by having a horizontal partition as a boundary, treats the sewage passed through the anoxic tank in the anaerobic condition after receiving the sewage through first outlet holes in the horizontal partition. The second reactor is connected to the first reactor by having a vertical partition in between, and treats the sewage passed through the anaerobic tank in the aerobic condition after receiving the sewage through second outlet holes in the vertical partition.