为了了解地下水中各种类铵氮临界絮凝铵氮浓度的差别,本文采用批试验，对天然黏土胶体、膨润土胶体、高岭土胶体和不同粒径的天然黏土胶体的临界絮凝铵氮浓度进行了测定。结果表明：不同种类胶体的临界絮凝铵氮浓度有差别，天然黏土胶体、膨润土胶体、高岭土胶体的临界絮凝铵氮浓度分别为1600 mg/L，24 000 mg/L和8 000 mg/L。试验结果表明膨润土的稳定性最强，最不易受到铵氮的影响。不同粒径天然黏土胶体的临界絮凝铵氮浓度也不同，但是随粒径的变化呈现出一定的规律性,随着粒径的增大临界絮凝铵氮浓度减小，说明粒径较大的胶体的稳定性越差，越易受到铵氮的影响。总体而言,胶体的临界絮凝铵氮浓度和胶体种类和胶体粒径都有一定的相关关系。

In order to study the critical flocculation concentrations of ammonia nitrogen in various kinds of colloids in the groundwater, we measured the critical flocculation concentrations of ammonia nitrogen in natural clay colloid, bentonite colloid, kaolin colloid, and natural clay colloids of different particle sizes in a batch test. Results showed that the critical flocculation concentration of ammonia nitrogen varies in different kinds of colloids. The critical flocculation concentrations of ammonia nitrogen in natural clay colloid, bentonite colloid, and kaolin colloid were 1600 mg/L, 24000 mg/L, and 8000 mg/L, respectively. Test results showed that the stability of the bentonite colloid was the strongest and was the least susceptible to ammonia nitrogen. The critical flocculation concentration of ammonia nitrogen also varies in natural clay colloids of different particle sizes. It tended to decrease with the increase of the particle size, indicating that the colloid with bigger particle size has worse stability and thus is more susceptible to ammonia nitrogen. In general, the critical flocculation concentrations of colloids are certainly associated with the type of colloid and the particle size of the colloid.

国家自然科学基金（41372231）；天津市应用基础与前沿技术研究计划重点项目（15JCZDJC41300)