过热器管道化学清洗试验研究  

Experimental study on chemical cleaning of superheater tubes

作　　者：陈超 庄文军 张祥金[2] 胡家元[3] 

机构地区：[1]神华广东国华粤电台山发电有限公司,广东台山529228 [2]西安热工研究院有限公司,陕西西安710032 [3]武汉大学动力与机械学院,湖北武汉430072

出　　处：《热力发电》2013年第1期67-72,共6页Thermal Power Generation

摘　　要：为避免过热器氧化皮脱落影响机组的安全运行,研究开发了2段清洗工艺对台山电厂600MW机组锅炉过热器管道氧化皮进行化学清洗试验。结果表明,该技术能够完全清除过热器管内壁的氧化皮,清洗过程不会出现大量氧化皮剥落而造成大量不溶性残渣沉积在过热器U型弯管内的现象,且对管材金属的腐蚀率均小于1.0g/(m2.h);清洗介质A可完全溶解低含铬量材质的氧化皮和90%左右含铬量较高材质的氧化皮,清洗介质B可完全清除含铬量较高材质底层难溶的富铬层;过热器中的奥氏体不锈钢未发生晶间腐蚀和应力腐蚀。In order to avoid the exfoliation of oxide layer on superheater that may affect the safe operation of the unit,a two-stage cleaning process was developed to conduct the chemical cleaning tests for the oxide layer on superheater of the 600 MW level boiler in Taishan power plant.The results showed that,this technology can completely clean the oxide layer.Large amount of insoluble residue depositing inside the U-shape pipes of the heater caused by exfoliation of a great deal of oxide layers did not occur.The metal corrosion rate for pipes of different materials were all below 1.0 g/(m2·h).The cleaning medium A can totally dissolve the oxide layer containing low content of Cr or dissolve 90% of the oxide layer containing high content of Cr.While for the bottom Cr-rich layer in material with high Cr content,the cleaning medium B can totally dissolve it.Additionally,the intergranular corrosion and stress corrosion didn't occur on the austenitic stainless steel of the superheater,which satisfied the cleaning requirements.

关 键 词：600 MW机组 锅炉 过热器 氧化皮 剥落 化学清洗 防腐 

分 类 号：TK224.9[动力工程及工程热物理—动力机械及工程]