某220MW超高压机组修后炉水pH突降原因分析  

The reason analysis of pH sudden drop in boiler water of a 220 MW ultra-high-pressure unit after repair

作　　者：李元浩 姜波 王鹏星 Li Yuanhao;Jiang Bo;Wang Pengxing(Northwest Electric Power Test&Research Institute,China Datang Corporation Science and Technology Research Institute Co.,Ltd.,Xi’an 710021,China)

机构地区：[1]中国大唐集团科学技术研究院有限公司西北电力试验研究院,陕西西安710021

出　　处：《工业水处理》2021年第2期123-126,共4页Industrial Water Treatment

摘　　要：某火电厂220 MW超高压机组修后出现水汽品质异常情况,炉水pH降到7以下,并达到水汽质量劣化三级处理要求,使机组面临极大地安全运行隐患。通过对化学在线仪表故障、固体碱化剂加入量、补给水水质、凝汽器泄漏等可能原因进行分析排查,发现凝结水精处理系统高速混床出现跑漏树脂的情况。凝胶型苯乙烯系强酸阳离子交换树脂,其在炉水中分解产生硫酸是造成炉水pH突降的根本原因。结合该案例针对树脂跑漏状况进行了可能原因分析并提出了相关对策。After repair 220 MW ultra-high-pressure unit in a thermal power plant,an abnormal water vapor quality problem occurred.The pH of the boiler water dropped below 7 and reached the three-level treatment requirement for water vapor quality degradation,which caused the unit to face great hidden dangers during safe operation.By analyzing and investigating possible reasons such as failure of the chemical online instrument,dosage of solid alkalizing agent,quality of supply water,and leakage of the condenser etc.,it was found that the resin leakage occurred in the high-speed mixed bed of the condensate fine processing system.The decomposition of gel-type styrene strong acid cation exchange resin in boiler water to produce sulfuric acid was the root cause of the sudden drop in the pH of the boiler water.Based on this case,the possible reason of resin leakage was analyzed and the related countermeasures were proposed.

关 键 词：凝结水精处理 炉水pH突降 树脂跑漏 树脂捕捉器 水帽 

分 类 号：TK223.5[动力工程及工程热物理—动力机械及工程]