Corrosion Reasons of Cooling Water Pipeline in Power Plant and Corresponding Measures

Corrosion protection measures are generally not taken for the inner wall of carbon steel pipelines in cooling water systems of power plants, and severe corrosion or even leakage may occur during operation. Corrosion leakage points are distributed in large and small tubes of cooling water systems, which makes maintenance difficult and affects the normal operation of the system. According to the corrosion cases of carbon steel pipelines in cooling water systems of three power plants, the corrosion causes were analyzed by X-ray fluorescence spectrometry, X-ray diffraction, energy dispersive spectroscopy, combined with the results of water quality test and corrosion morphology characteristics. The results show that the corrosion of inner wall of carbon steel pipeline was aggravated because of microbial corrosion. The deposition of a large number of corrosion products induced local autocatalytic corrosion under deposits. And finally the pipeline leaked. It is suggested to choose appropriate countermeasures and measures from two aspects of system operation control and pipeline material, combining with the actual situation, to avoid corrosion and leakage of carbon steel pipeline inner wall.