某东南沿海电厂钢结构腐蚀影响因素分析

目的 对比腐蚀环境因子分布和钢结构腐蚀事件分布，分析影响火力发电厂钢结构腐蚀的主要环境因素，探讨火力发电厂钢结构腐蚀的机理。方法 以东南沿海某火力发电厂为例，对电厂厂区进行网格化，利用便携式温湿度计进行逐网格温、湿度监测，逐网格收集结构物表面灰尘，并分析其中氯离子、可溶盐、酸碱含量等，开展腐蚀环境监测。统计从2012年至2022年10年间该电厂每一网格内的腐蚀防护工程，如腐蚀防护器件、装备、材料购置等项目的施工或应用次数。结果 温度、湿度及钢结构表面灰尘中氯离子含量、可溶盐含量、灰尘浸渍水p H等因子受海洋环境、厂区结构分布、生产活动多重原因的影响，随距海距离增加呈带状分布，或围绕生产设施点呈辐射分布。结论 环境因子对钢铁结构腐蚀的影响大小顺序为结构物灰尘含盐量>结构物灰尘浸渍水p H>相对湿度>结构物灰尘氯离子含量>温度。电厂钢结构腐蚀机理为雨水或大气凝结水溶出结构物表面灰尘的可溶性盐，含盐水经涂层缺陷输运至金属表面，成为钢铁腐蚀原电池的离子导路，导致钢结构发生电化学腐蚀。

Analysis of Corrosion Factors of Steel Structure in a Southeast Coastal Power Plant

The work aims to compare the distribution of corrosion environmental factors and the distribution of steel structure corrosion events, analyze the main environmental factors affecting the corrosion of steel structure in thermal power plants, and explore the corrosion mechanism of steel structure in thermal power plants. Taking a southeast coastal power plant as an example, the plant area was gridded. The portable temperature and humidity meter was used to monitor the temperature and humidity grid by grid, and the dust on the surface of the structure was collected grid by grid, and the contents of chloride ions, soluble salts, acid and alkali were analyzed, so as to monitor the corrosion environment. The corrosion protection projects in each grid of the power plant during the decade from 2012 to 2022 were counted, such as the number of construction or application of corrosion protection devices, equipment and materials. The factors such as temperature, humidity, chloride ion content, soluble salt content and dust-soaking liquid pH on the surface of steel structures were affected by multiple factors such as marine environment, factory structure distribution and production activities, and they were distributed in strips with the increase of distance from the sea or radiated around production facilities. The order of effect of environmental factors on corrosion of steel structure:soluble salt of SSSD>soluble salt of SSSD>dust-soaking liquid pH of SSSD>humidity>chloride content of SSSD>temperature. The corrosion mechanism of the steel structure in the power plant is the salt of SSSD dissolved in the rain or atmospheric condensate water, and the saline water is admitted to the surface of steel structure through the coating faults and becomes the ion conduction path of primary cells for steel corrosion and then the electrochemistry corrosion of steel is triggered or exacerbated.