Method of Removing Nitrogen and Phosphorus in Industrial and Domestic Wastewater

摘要

PURPOSE: To provide a method for solving food waste problems and reducing treatment cost at the same time, maximally inducing discharge of phosphorus without inhibition of nitrate and effectively removing nitrogen and phosphorus without installation of inner circulation device by maximally using organic matter contained in raw sewage in case that food waste is not obtained. CONSTITUTION: The method comprises a step of removing organic matter and nitrate in sewage by supplying raw sewage into first anoxic tank; a step of discharging phosphorus by flowing treated water of the first anoxic tank in an anaerobic tank; a step of removing organic matter in sewage and inducing nitrification of ammonia nitrogen at the same time by sending treated water of the anaerobic tank to first aerobic tank; a step of removing nitrate contained in the treated water treated in the first aerobic tank by supplying treated water treated in the first aerobic tank and an acid fermentation liquid in which food waste and raw sludge are fermented into second anoxic tank; a step of sending treated water of the second anoxic tank to second aerobic tank so that nitrogen gas is degassed, and residual organic matter is finally oxidized; a step of separating sludge from treated water of the second aerobic tank in a final settling chamber so that sludge separated treated water is discharged; and a step of returning the sludge of the final settling chamber to the first anoxic tank, wherein the method further comprises a step of injecting the acid fermentation liquid into the anaerobic tank.