Abstract:

In view of the fact that the concentration of ammonia nitrogen and sulfide in purified water of a refinery stripping unit has not reached the design index, a comprehensive analysis, process optimization and experimental research were carried out. The results showed that the poor water quality of non-hydrogenated acid water was the main reason that affected the stripping efficiency. By reducing the total oil and volatile phenol content of stripping feed water and improving the steam quality of stripping tower, the purified water quality had been obviously improved, but the mass concentration of sulfide was still more than the design index of 20 mg/L. It was found that volatile phenol and alkalinity tended to make the measurement result larger when determining sulfide by iodometry, while the real value of this purified water was lower than the design index. In order to reduce the interference of volatile phenol and measurement error, it was suggested to adopt the pretreatment methods of fixation, separation and acidification air blowing when determining sulfide by iodometry.

Key words: stripping purified water, ammonia nitrogen, sulfide, volatile phenol, iodometric method

摘要：

某炼油厂汽提装置净化水中氨氮和硫化物浓度一直没有达到设计指标，为此进行了全面分析、工艺优化和试验研究。结果表明，非加氢型酸性水较差的水质是影响汽提效率的主要原因，减少汽提原料水总油和挥发酚含量，并提高汽提塔蒸汽品质，净化水水质得到明显改善，但硫化物质量浓度仍然大于20 mg/L的设计指标。研究发现，用碘量法测定硫化物时挥发酚和碱度易使测量结果偏大，而该净化水的实际值已低于设计指标，为减少挥发酚的干扰和测量误差，建议碘量法测定硫化物时采用固定、分离及酸化吹气预处理方式。

关键词: 汽提净化水, 氨氮, 硫化物, 挥发酚, 碘量法