锅炉EDTA清洗工艺条件探讨

Discussing of Boiler EDTA Cleaning Technics Conditions

本文介绍了EDTA化学清洗的原理、工艺，EDTA4~盐和铵盐清洗工艺条件（包括EDTA浓度、温度、pH值、流速、清洗时间）的选择、控制，清洗、钝化终点的判断，清洗过程中的技术监督；也介绍了某电厂≠}5新建锅炉采用EDTA铵盐清洗的清洗范围、清洗回路、清洗工艺参数、清洗效果。认为EDTA清洗具有工艺简便，清洗范围大，腐蚀速率小，清洗时间较短和对人身、设备安全可靠等特点；实际清洗中，应科学而严格地控制好影响EDTA清洗质量的因素，包括清洗液温度、浓度、pH、流速等参数，并在清洗过程中切实做好化学监督，控制最佳的清洗工艺，保证化学清洗达到最优效果。该电厂#5新建锅炉采用EDTA铵盐清洗取得了良好效果。

The priciple and technics of the chemical cleaning with EDTA, the choice and control of technological conditions （including the concentration of EDTA, the temperature, the pH value, the velocity of flow and the cleanin-g time）, the judgement on the ultimate cleaning and passivation, and the technological supervision of the chemical cleaning with the EDTA ammonium and sodium salt were illustrated. Chemical cleaning were characterized with simplicity, wide range, safety and shorter time spent in cleaning. In practice, the factors affecting EDTA cleaning performance, including the parameters such as, cleaner temperature, concentration, pH, flow rate; as well as the process of cleaning and the optimal cleaning to achieve the best cleaning performance. The #5 new-built boiler adopting EDTA ammonium salt as cleaner in the power plant is a good example of this case.