Investigating the destructive effects of improper control of CWT chemical regime in the operation of combined cycle power plant; a case study
Subject Areas : journal of New Materials
Abbas Yousefpour
1
*
,
Ali Bakhshi
2
,
Hossein Ghaseminejad
3
,
Mohsen Esmaeilpour
4
,
Danak Kohzadi
5
,
Seyedeh Yas Farzaneh
6
1 - Chemistry and Process Research Department, Niroo Research Institute (NRI), Tehran, Iran
2 - Power Plant Monitoring and Control Research Department, Niroo Research Institute (NRI), Tehran, Irann
3 - Chemistry Department, Niroo Research Institute
4 - Assistant Professor, Chemistry and Process Research Department, Niroo Research Institute, Tehran, Iran
5 - Faculty of Petroleum and Chemical Engineering at Islamic Azad University – Tehran Science and Research Branch, Tehran, Iran
6 - Faculty of Petroleum and Chemical Engineering at Islamic Azad University – Tehran Science and Research Branch, Tehran, Iran
Keywords: Combined Cycle Power Plant, Chemical Water Treatment (CWT) Regime, Dissolved Oxygen (DO), Electrical Conductivity,
Abstract :
The implementation of an effective chemical regime in combined cycle power plants is crucial for ensuring optimal performance. It plays a key role in preventing issues such as tube perforation, forced shutdowns, frequent maintenance, and reduced boiler performance and efficiency, all of which can negatively impact power generation. In this study a comprehensive instruction was proposed for high performance chemical control. This study investigated the challenges faced in managing the Chemical Water Treatment (CWT) regime at the Fars Combined Cycle Power Plant. Through a series of water and steam cycle tests and sampling from the boiler drum outlet, it was found that certain parameters exceeded the allowable limits and did not comply with the plant's operational guidelines or EPRI standards. The analysis of water samples, compared with international quality control standards, revealed that high pH levels in certain sections of the cycle and dissolved oxygen (DO) concentrations exceeding the permissible limit by more than four times were directly correlated with increased rates of corrosion.
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