过热器氧化皮催化柠檬酸清洗研究及应用

随着大容量、高参数火力发电机组的投产运行，因氧化皮脱落而引起的过热器管爆管已成为影响机组安全运行的主要原因之一。为此，研究开发了催化柠檬酸清洗介质对过热器管氧化皮进行化学清洗的技术，并成功应用于600 MW机组锅炉过热器的清洗。工程应用结果表明，该技术能够有效清除过热器管内壁的氧化皮，且不会出现大量氧化皮剥落所形成的堵管现象；化学清洗过程中各种材质的平均腐蚀速率均达到了《火力发电厂锅炉化学清洗导则》（DL/T 794—2012）的规定值；化学清洗后机组启动及正常运行中，系统水汽指标良好，过热器管壁温度偏差正常，达到了清洗目的。

Study and Application of Catalytic Citric Acid Cleaning of Superheater Tubes

With the commissioning of large-capacity and high-parameter power generating units, the superheater tube failure due to the iron oxide deposits falling off has become one of the main causes affecting the safe operation of the power generating unit. Therefore, the study on the technology of chemical cleaning using catalytic citric acid cleaning medium for superheater tube scale is conducted and the study results are successfully applied to the superheater of a 600-MW unit. The application shows that this technology can effectively remove the oxide layer on the superheater tubes without causing significant exfoliation of the oxide layer. All the average corrosion rates of different materials in the cleaning process meet the specified values in the chemical cleaning guide for thermal power plant boilers (DL/T 794-2012). During the unit startup and regular operation after the chemical cleaning, the quality of water and steam is good and the superheater wall temperature excursion is normal, realizing the goal of chemical cleaning.