Abstract: The ammonia nitrogen(NH₄⁺-N) concentration in effluent of a chemical industrial wastewater treatment plant had significant annual variations. The pH, concentrations of NH₄⁺-N, anions, metals in influent were not the reasons for inhibiting nitrification and causing the NH₄⁺-N concentration over the standard value in winter and spring. The continuous flow experiments in laboratory showed that dissolved oxygen and mixed liquor suspended solids did not inhibit the nitrification, and were not the reasons for NH₄⁺-N concentration over the standard value in winter and spring. Further analysis showed that the air temperatures had significantly effect on the NH₄⁺-N concentration in effluent and there were two different critical lowest air temperatures. In summer, NH₄⁺-N concentration did not decrease as air temperature rise until it reach to critical lowest air temperature 19-21℃ and then it kept stable in effluent. In winter, NH₄⁺-N concentration in effluent also kept stable as air temperature gradually decreases until the air temperature reach to another critical lowest air temperature 3-5℃ and then steady beyond the standard value. Addition of glucose can improve the removal rate of ammonia nitrogen when the air temperature was too low.

Key words: chemical industrial park, effluent, ammonia nitrogen, influence factor, temperature

摘要： 化工园区工业污水处理厂生化出水氨氮呈现出显著的周年变化。对进水水质进行分析，发现进水pH、氨氮浓度、阴离子浓度、重金属离子浓度均不是影响冬春季该工业污水厂生化出水氨氮不达标的原因。实验室连续流小试试验表明，好氧池污泥浓度、溶解氧也不是显著影响冬春季工业污水厂生化出水氨氮不达标的原因。进一步分析表明，温度显著影响该工业污水厂生化出水氨氮浓度，且存在不同的阈值。在夏季温度逐渐升高时，出水氨氮并没有逐渐下降，而是在当地最低气温达19~21℃时，出水氨氮才迅速下降并保持稳定；在冬季温度逐渐降低时，出水氨氮并没有逐渐升高，而是在当地最低气温达3~5℃时，出水氨氮迅速上升并保持稳定，且超出排放标准。温度较低时可以投加葡萄糖，提高对氨氮的去除能力。

关键词: 化学工业园区, 生化出水, 氨氮, 影响因子, 温度