Thermo-Mechanical Analysis of Sulfuric Acid Corrosion in Preheaters: Fars Combined Cycle Power Plant Case Study

This study examines the impact of preheater tubes within the Heat Recovery Steam Generator (HRSG) on the operational performance of the Fars combined cycle power plant located in Shiraz, Iran. Since combined cycle power plants utilize various fuels, high sulfur fuels, (typically distillated oil as the liquid fuel) would require bypassing the preheater entirely. It means that the water is allowed to be flowed directly into the low-pressure drum. As a result, the preheater section of the HRSG is activated only when natural gas is used as the fuel source. Nevertheless, operational observations at Fars power plant indicate that combustion products still contain traces of sulfur, which gradually forms corrosive acids on the surface of preheater tubes. To address this issue, this paper explores the effects of the preheater on power generation as well as other cycle parameters. It aims to develop an effective strategy to mitigate corrosion while maintaining efficiency in a mathematical study as well as outcome validation against manufacturer specifications and performance data from Fars power plant operations. In this case study, findings reveal that controlling the preheater bypass based on metal temperature would effectively manage the corrosion leasing to the maintenance costs reduction.

کلیدواژه ها:

Corrosion ، HRSG ، Modeling ، Power Plant ، Preheater