Harmless treatment method for phosphate tailings

The invention discloses a phosphorus tailing harmless treatment method, and relates to the technical field of phosphorus tailing treatment. The method comprises the steps that flotation tailings are subjected to size mixing and then pumped into a cyclone to be concentrated, fine fraction is removed, overflow of the cyclone enters a tailings pond, sand settled by the cyclone enters a stirring tank, and an efficient phosphorus fixing agent and lime are added to cooperate for primary phosphorus fixing; after primary phosphorus fixation, ore pulp is pumped into a filter for dehydration, a filter cake and lime are fully and evenly mixed for secondary phosphorus fixation, phosphorus tailings obtained after harmless treatment are obtained, and stockpiling or stope backfilling treatment is conducted. The treatment process of cyclone concentration grading, efficient phosphorus fixing agent/lime synergistic primary phosphorus fixing, filter pressing dehydration and lime powder secondary phosphorus fixing is adopted, th