核电站蒸汽发生器的化学清洗与传热性能

Chemical cleaning and heat transfer performance of steam generator in nuclear power station

核电站经过多年运行,蒸汽发生器传热管会被大量的微粒和溶解化学物质沉积所沾污。蒸汽发生器的化学清洗可以维持核电站的正常运行、恢复蒸汽压力和增强管道的耐腐蚀能力。有的电站进行化学清洗是为了有效清除支撑板拉制孔上的污垢,稳定水位波动,使电站恢复到全功率下稳定运行。一般,清除管道上的污垢后,能恢复蒸汽发生器的蒸汽压力,并使支撑板、管道间隙和管道直段上无沉积物,从而可以增强管道的耐腐蚀能力。另外,化学清洗改变了管道的微观表面、沸腾传热和传热性能。本文介绍了对蒸汽发生器采用EDTA的化学清洗,以及清洗后的污垢热阻、沸腾传热和传热性能。

After many years of nuclear power station operation, steam generator tubes became fouled with significant deposit of particulate and dissolved chemical. Chemical cleaning of steam generator is to maintain plant normal operation, recovering steam pressure and increasing tube corrosion resistance. Some plant implemented chemical cleaning for removing scale from tube support plate broached hole for restoring stable water level oscillations and returned a plant to a stable operation at the full power level. General, removal of the tube scale recoveres steam pressure and increases the corrosion resistance margin for the cleaned tube being free of chemical concentration sites, such as tube support plate and tube crevices, open span tube deposit pores. In addition, chemical cleaning can change the tube microsurface, boiling heat transfer and heal transfer performance. This paper describes using the ethylenediaminetetraacetic acid（EDTA） chemical cleaning, post -cleaning fouling heat resistance, boiling heat transfer and heat transfer performance.