发电机内冷却水系统高含量单质铜垢的化学清洗

Chemical Cleaning for Inner Cooling System in Generator with High Content Copper Deposition

发电机内冷却水(内冷水)系统腐蚀及腐蚀产物沉积所引起的绝缘性能与通流冷却能力下降,是发电机运行的重要安全隐患。某发电厂发电机内冷水系统出现堵塞、超温异常,其腐蚀产物中单质铜含量高。为消除隐患,首次采用以氨基磺酸为主的复合酸并添加双氧水作为清洗介质,辅以分步去除氧化铜和单质铜的工艺,对该发电机内冷水系统实施了化学清洗。结果表明,所采用的清洗工艺技术有效去除了线棒内的腐蚀产物,且对线棒本体损伤较小;与清洗前相比,清洗后定子线棒最高温度下降了9.9℃,线棒间最大温差下降了10℃,不同线棒间出水最大温差下降了11℃,确保了发电机安全经济运行。

Insulation deterioration and cooling capacity decrease due to corrosion and deposition of corrosion products in innercooling water system are potential threats to generator operation. At a power plant of Hunan Province, abnormal temperature andblockage are observed in the generator inner cooling water system with high content copper in the corrosion products. To address thepotential issues, chemical cleaning is carried out for the first time by using amino sulfonic acid based composite acid with theaddition of hydrogen peroxide in combination with multi-step rinse process to eliminate copper oxides and copper. The resultsindicate that, by taking advantage of this technology the inner corrosion products are effectively cleared with very few damages to thestator bar. The before and after comparison shows that the temperature of stator winding during operation was reduced up to 9.9 ℃.The maximum temperature difference between stator coil bars is reduced by 10 ℃, while the maximum temperature differencebetween the water outlets from stator coil bars dropped by 11 ℃, respectively. In this way the secure and economical operation ofgenerator can be ensured.