Treatment method of wastewater containing ammonium nitrate

The invention discloses a treatment method of wastewater containing ammonium nitrate. The treatment method comprises the steps as follows: magnesium oxide is added to the wastewater containing ammonium nitrate for slurry making, the slurry is heated to be boiled, heated continuously and continuously supplemented with tap water for ammonia vitalization, and ammonia water and condensate water are recovered; calcium oxide is added to ammonia evaporation raffinate after evaporation ends, and impurity-removed filtrate is obtained after liquid-solid separation; the impurity-removed filtrate is slowly stirred and subjected to cooling crystallization, filtration is performed, and magnesium nitrate crystals are obtained; the magnesium nitrate crystals are dried at the temperature of 40-100 DEG C for 1-3 h, then, the magnesium nitrate crystals are calcined at 300-600 DEG C for 1-3 h after drying to be decomposed into magnesium oxide and nitrogen oxide, the magnesium oxide returns to the ammonia evaporation process to b