Extensive feedwater quality control and monitoring concept for preventing chemistry-related failures of boiler tubes in a subcritical thermal power plant

• Published in: Applied thermal engineering 2013-09, Vol.59 (1-2), p.683-694
• Main Authors: Vidojkovic, Sonja, Onjia, Antonije, Matovic, Branko, Grahovac, Nebojsa, Maksimovic, Vesna, Nastasovic, Aleksandra
• Format: Article
• Language: English
• Subjects: Applied sciences; Boiler tubes; BOILERS; CORROSION; Corrosion prevention; CORROSION PROTECTION; Energy; Energy. Thermal use of fuels; Exact sciences and technology; FAILURE; Feedwater; Feedwater quality; Heat transfer; Installations for energy generation and conversion: thermal and electrical energy; MAINTENANCE; Power plants; QUALITY CONTROL; Theoretical studies. Data and constants. Metering; Thermal power plant; Thermal power plants; Thermoelectricity; TUBE
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2013.06.028

Prevention and minimizing corrosion processes on steam generating equipment is highly important in the thermal power industry. The maintenance of feedwater quality at a level corresponding to the standards of technological designing, followed by timely respond to the fluctuation of measured parameters, has a decisive role in corrosion prevention. In this study, the comprehensive chemical control of feedwater quality in 210 MW Thermal Power Plant (TPP) was carried out in order to evaluate its potentiality to assure reliable function of the boiler and discover possible irregularity that might be responsible for frequent boiler tube failures. Sensitive on-line and off-line analytical instruments were used for measuring key and diagnostic parameters considered to be crucial for boiler safety and performances. Obtained results provided evidences for exceeded levels of oxygen, silica, sodium, chloride, sulfate, copper, and conductivity what distinctly demonstrated necessity of feedwater control improvement. Consequently, more effective feedwater quality monitoring concept was recommended. In this paper, the explanation of presumable root causes of corrosive contaminants was given including basic directions for their maintenance in proscribed limits. •Feedwater quality monitoring practice in a thermal power plant has been evaluated.•The more efficient feedwater quality control have been applied.•Analysis of feedwater quality parameters has been performed.•Exceeded levels of corrosive contaminants were found.•Recommendations for their maintenance at proscribed values were given.