The utility model relates to the technical field of biological
nitrogen and
phosphorus removal equipment, in particular to a biological
nitrogen and
phosphorus removal device. The utility model provides a biological
nitrogen and
phosphorus removal device convenient for cleaning
sludge. The biological nitrogen and phosphorus removal device comprises a mounting seat, an
anaerobic chamber, an anoxic chamber, an aerobic chamber, a
sedimentation tank, a shunt
pipe, a screw rod, a limiting rod, a first scraper blade and the like, four chambers are arranged in the mounting seat and sequentially comprise an
anaerobic chamber, an anoxic chamber, an aerobic chamber and a
sedimentation tank from front to back, the rear part of the mounting seat is rotatably connected with a screw rod, the rear part of the mounting seat is provided with a limiting rod, the limiting rod is located behind the screw rod, the limiting rod and the screw rod are both located in the
sedimentation tank, and first scraping plates are symmetrically connected between the limiting rod and the screw rod in a sliding manner; the first scraper contacts with the bottom of the mounting seat. By rotating the screw rod, the two first scrapers move towards the middle along the limiting rod, and
sludge attached to the bottom of the sedimentation tank is scraped, so that the effect of cleaning the
sludge is achieved.