| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a device by which nitrogen and phosphorus are removed simultaneously in high percentages of removal, and the phosphorus can be recovered as a value-added phosphorus resource. SOLUTION: The method and the device for treatment of nitrogen and phosphorus-containing wastewater include (A) adsorption of ammoniacal nitrogen onto zeolite, by passing the nitrogen and phosphorus-containing wastewater, whereto phosphorus-adsorbing fine particles having been added, through a zeolite-filled layer, followed by removing of the particles by washing the zeolite- filled layer with water, when resistance to filtration is increased, (B) desorption of phosphorus from the particles by the addition of an alkali to the emulsion discharged from the filled layer and containing the fine particles, and crystallizing-out of insoluble phosphorus compounds by the addition of Ca or Mg to the water containing phosphorus thus desorbed, and (C) biological nitrification of ammonia on the zeolite by the addition of the alkaline effluent obtained by the process (B) to the filled layer while aerating with oxygen-containing gas, when ammonia concentration in the effluent from the filled layer is increased. |
