1 000 MW超超临界机组长周期给水加氧实践效果分析与评价

对华能海门电厂2号机组（1 000 MW超超临界机组）给水加氧处理效果进行总结和分析。结果表明：给水采用加氧处理后,省煤器入口给水、高压加热器（高加）疏水的铁质量浓度平均值降至1 μg/L以下,较之前的弱氧化性全挥发处理降低了80%以上,有效抑制了炉前给水和高加疏水系统的流动加速腐蚀,减少了腐蚀产物向锅炉水冷壁、省煤器的转移量,进而降低了锅炉水冷壁和省煤器结垢速率,减缓了锅炉压差上升速率,避免了高加疏水调节阀堵塞,凝结水精处理系统混床周期制水量也由之前的8万t提高至40万t,节能降耗效益非常可观。由此证明给水加氧处理对提高机组运行的安全性、可靠性、经济性具有重要意义。

Analysis and Assessment on Effect of Long-Term Oxygenated Treatment for 1 000-MW Ultra Supercritical Units

In this paper the effect of oxygenated treatment(OT) for boiler feedwater of Unit 2(a 1 000-MW ultra supercritical unit) at Huaneng Haimen Power Plant is summaried and analyzed. Since OT is used for the unit, the iron concentration atthe economizer inlet and in the high-pressure heater has been reduced to less than 1 μg/L, and decreased by more than 80% of that of all volatile treatment (oxidation) (AVT(O)), which effectively inhibits flow-accelerated corrosion in the feedwater and high-pressure heater drainage systems, reduces the iron transport and lowers the scaling rate in the economizer and on the water walls. The long-term operating experience shows that OT can not only slow down the boiler pressure dropping rate and avoid blocking of the drainage water control valve for the high-pressure heater, but also increasethe periodic water output of mixed bed in the condensate polishing system from 80 000 tons to 400 000 ton S, indicating a very considerable result of energy saving and consumption reducing, which is significant in improving the safety, reliability and economy of the unit.