Abstract:Ammonia-nitrogen-bearing wastewater from rare earth industry was treated by chemical precipitation and break point chlorination. Chemical precipitation tests results indicate that removal rate of NH4 -N is 90.64% under the conditions of pH=7 and precipitation time of 15 minutes. Break point chlorination tests results indicate that NH4 -N in rare earth wastewater can be reduced to 8.35 mg/L under the conditions of pH=7, 1.4 times of theoretical dosage of sodium hypochlorite solution and reaction time of 15 minutes. The treated wastewater meets the standard of RE industrial wastewater ammonia emissions, and the treating processes are economically feasible.