摘要
针对采用柠檬酸进行热力设备化学清洗时易产生沉淀的问题,通过试验模拟实际清洗条件,研究了沉淀的类型、产生的条件、沉淀产生的机理,并提出了控制措施。研究表明:柠檬酸清洗产生沉淀是因为清洗液中高浓度的Fe2+与未电离的柠檬酸结合形成柠檬酸亚铁,超过了其溶度积常数而产生沉淀。在一定的清洗条件下(初始柠檬酸浓度、pH值、温度),影响沉淀的主要因素为Fe2+浓度,因此,建议:在采用柠檬酸化学清洗前,根据实际清洗系统条件,通过试验确定极限Fe2+浓度;也可加入专用防沉淀剂抑制沉淀的产生。
The citric acid is easy to cause precipitation during chemical cleaning for thermal power equipments.Thus,a series of experiments simulating the practical chemical cleaning conditions were conducted to figue out the mechanism of precipitation,including the classification of precipitates and the factors affecting the precipitation.Based on the achieved mechanism,the controlling measures were proposed.The results show that,for the high concentration of Fe^2＋reacting with the unionized citric acid available in solution,ferrous citrate,who has a low solubility,is formed,resulted in precipitation.Under the confirmed cleaning conditions（initial citric acid concentration,pH,temperature）,Fe^2＋concentration is the dominating factor affecting the precipitation.It is suggested that specific erperiments should be performed to define Fe^2＋concentration in citric acid cleaning liquid prior to chemical cleaning.A specified anti-sedimentation agent can also be utilized to prevent precipitation.
出处
《热力发电》
CAS
北大核心
2015年第1期96-99,共4页
Thermal Power Generation
基金
华能集团重点科技项目(HNKJ10-H08)
关键词
柠檬酸
化学清洗
沉淀
机理
PH值
亚铁离子
citric acid
chemical cleaning
precipitation
mechanism
pH value
ferrous ion
