Boiler corrosion and monitoring

Abstract

Results of a collaborative effort to investigate and develop solutions for key material issues affecting the performance of large-scale coal-fired boilers operating at advanced conditions is presented. Advanced conditions include advanced steam temperatures, oxyfuel firing, and co-firing biomass materials. A series of laboratory experimental results are presented on fireside corrosion in environments representing air-, and oxy-fired conditions, and with coal and/or biomass as the fuel. The effects of fluctuating reducing atmospheres and heat flux effects were examined. A variety of boiler corrosion probes and sensors were developed and tested. The probes measured corrosion by section loss and the sensors by electrochemical techniques including electrochemical noise. The probes were tested in coal and waste-to-energy boilers. Correlations between section loss probes and electrochemical noise sensors allow for real-time corrosion rate measurements to be made that allow for changes in boiler operations to be tracked in terms of corrosion effects.     

富氧燃烧气氛石灰石溶解特性研究

在实验室小型试验台上研究富氧燃烧气氛下湿法脱硫用石灰石溶解特性,研究结果表明：较高的CO₂浓度对石灰石的溶解有促进作用,CO₂体积分数在80%时,石灰石的溶解速率明显增大;在相同的pH值情况下,CO₂浓度越高,石灰石的溶解速率越快。在pH=4.5时,低浓度CO₂气氛比高浓度CO₂气氛下溶解时间增加70 min,CO₂浓度对溶解速率的影响比较明显。