NOVELTY - Treatment of ammonia-nitrogen wastewater involves introducing high-temperature acidic wastes from nitric acid production process to fine distilled tower, separating nitrate, discharging concentrated nitric acid solution, and returning into nitric acid production system; mixing discharged nitrate and ammonium nitrate solution, purifying through ion exchange column, carrying out anion exchange, removing nitrogen oxide, and discharging industrial wastewater or using as make-up water for recycling; and absorption filtering and returning to ammonium nitrate production process.    USE - Method for treating ammonia-nitrogen wastewater used for producing nitric acid/ammonium nitrate (claimed) as fertilizer.    ADVANTAGE - The method optimizes conventional sewage treatment process, controls pollution, and has sewage zero discharge.    DETAILED DESCRIPTION - Treatment of ammonia-nitrogen wastewater comprises: (A) introducing high-temperature acidic wastes from nitric acid production process to fine distilled tower, separating nitrate through acidic waste volatilization temperature difference of nitric acid vapor and water vapor, discharging concentrated nitric acid solution, and returning into nitric acid production systems; (B) mixing discharged nitrate and ammonium nitrate solution, purifying through ion exchange column, feeding into ion exchange column, exchanging hydrogen-type resin groups with water-ammonium ion cation, absorbing hydrogen ions in dilute nitric acid and first level processing solution, using dilute nitric acid in first ion exchange column, using first level processing solution in second ion exchange column by hydroxyl group resin with water-nitrogen oxide, carrying out anion exchange, absorbing water in nitrogen oxide, removing nitrogen oxide to get ammonium nitrate solution and GB-26131 nitric acid industry emission standards wastewater, and discharging industrial wastewater or using as make-up water for recycling; and (C) absorption filtering to remove metal ions and organic compounds and returning to ammonium nitrate production process.