尿素漏入引起机组水汽品质劣化的事故分析及处理  

Analysis and treatment of water-steam quality deterioration of generating unitscaused by urea leakage

作　　者：徐兴宪 XU Xingxian(Zhangjiagang Shazhou Elecrtic Power Company,Zhangjiagang,Jiangsu 215600,China)

机构地区：[1]张家港沙洲电力有限公司,江苏张家港215600

出　　处：《浙江电力》2023年第10期114-118,共5页Zhejiang Electric Power

摘　　要：燃煤电厂实施液氨改尿素工程后,若尿素漏入机组水汽系统会产生水汽品质劣化现象。以一起因尿素漏入水汽系统导致1000 MW机组非计划停运的事故为例,从事故现象、处理过程、排查分析过程、制定防范措施、诊断手段等方面展开论述。给水氢导电率异常升高是主要事故现象;通过分析给水氢导电率、铵离子与除盐水及凝结水TOCi含量关联变化的规律,找出事故原因是尿素漏入水汽系统;通过系统排查,找出源头是尿素站废水污染了发电厂原水。同时提出了预防尿素漏入的措施以及诊断尿素漏入的手段。After the implementation of the liquid ammonia to urea conversion project in a coal-fired power plant,urea leakage into the steam-water system of unit may lead to deteriorated steam-water quality.With an unscheduled shutdown of a 1,000 MW unit due to urea leakage into water-steam system as an example,the accident phenom⁃enon,treatment process,investigation and analysis process,formulation of precautionary measures,and diagnostic means are discussed.Abnormal increase of feedwater hydrogen conductivity is the main accident phenomenon.Through analysis the laws of correlation between feedwater hydrogen conductivity,ammonium ions and TOCi con⁃tents of demineralized water and condensate,it is determined that the accident is caused by leakage of urea into the water-steam system.The systematic investigation shows that the accident results fundamentally from the contamina⁃tion of raw water in the power plant by wastewater from the urea station.Meanwhile,measures to prevent urea leak⁃age into the water-steam system and means to diagnose urea leakage into the system are proposed.

关 键 词：尿素制氨 水汽品质 氢电导率 事故分析 

分 类 号：TM621[电气工程—电力系统及自动化]