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The pollution caused to the environment by nitrogen-containing wastewater discharged during industrial production, nitrogen fertilizers used in agriculture that are washed into rivers and lakes via rainwater, and domestic sewage discharged into water bodies is becoming increasingly severe, and has drawn widespread concern. This is because NO3- is harmful to human health. After entering the human body, NO3- is reduced to NO2-, which is carcinogenic. Furthermore, NO3- inhaled by infants and young children enters the bloodstream and reacts with hemoglobin, oxidizing Fe(II) to Fe(III), thereby forming methemoglobin. Methemoglobin binds irreversibly to oxygen, causing methemoglobinemia. The drinking water quality standards issued by the World Health Organization (WHO) stipulate that the maximum permissible concentration of NO3--N is 10 mg/L. However, in some provinces and cities in China, the NO3--N content in groundwater reaches as high as 20–50 mg/L. Nitrates have high solubility in water and good stability, and it is difficult for them to form coprecipitates or undergo adsorption. Therefore, traditional simple water treatment techniques, such as lime softening and filtration, are difficult to remove nitrates from water. The principle of the ion exchange method is that NO3- in the solution is removed by exchanging it with Cl- or HCO3- on the ion exchange resin. After resin exchange saturation, it is regenerated using NaCl or NaHCO3 solutions. Generally, the order of selectivity of anion exchange resins for several anions is: HCO3- < Cl- < NO3- < SO42-. Therefore, it is difficult to remove nitrate from water containing sulfates using conventional methods. Because the resin exchanges almost all of the sulfates in the water before exchanging them for the nitrates in the water. In other words, the presence of sulfates reduces the resin’s ability to remove nitrates. Current ion exchange methods: they lack selectivity, require frequent regeneration, and produce unstable water quality. Ordinary anion exchange resins exchange anions in the order of SO42- > NO3- > HCO3-; they show no selectivity for nitrates, preferring to exchange sulfate ions first. This leads to frequent resin regeneration, an increased concentration of chloride ions in the produced water, poor stability of the water quality, low exchange capacity of the resins, and even an \"avalanche\" phenomenon during use (a sudden spike in the nitrate content of the water produced by the resin, exceeding the level in the input water). Using a resin with preferential selectivity for nitrates can effectively solve this problem. This resin preferentially exchanges nitrates, and its exchange capacity for nitrates is not affected by sulfates in water. The A-62MP is a nitrate-specific resin; this resin, whose functional groups have been modified, exhibits preferential adsorption of nitrates. Its exchange capacity for nitrates is not affected by the sulfate content in water, offering high precision and a large exchange capacity. Key parameters: Type: Macroporous strong-base anion exchange resin (for food use); Functional group: Type I quaternary ammonium functional group; Treatment precision: 0.1 mg/L; Regenerating agent: Sodium chloride (at a concentration of around 10%); Amount of regenerating agent required: 1 BV–2 BV; Regeneration flow rate: 2 BV/hour; Regeneration time: 30–60 minutes; Backwash water: Pure water/softened water/tap water; Backwash flow rate: 5–10 BV/hour; Backwash time: 30 minutes. Differentiating advantages: 1. High treatment precision – nitrate nitrogen (including nitrite and nitrate) can be reduced to below 1 ppm, meeting Class III surface water standards. It is an excellent choice for projects aimed at upgrading water treatment standards ； 2. It has a high adsorption capacity; the saturated adsorption capacity for nitrates (expressed in terms of N) can exceed 10 g/l ； 3. Resins preferentially exchange nitrates, and their exchange capacity for nitrates is not affected by the sulfate content in the water ； 4. Food-grade materials that can be used for the advanced removal of nitrate nitrogen from drinking water, groundwater, mineral water, mine water, wastewater, etc ； 5. It features a modular component design, offering a high degree of automation and simple operation.