SCR脱硝系统中尿素热解装置防结晶对策探讨

The discussion of countermeasures for urea crystal issue in SCR urea pyrolysis system

尿素热解制氨由于其在安全方面的优势,已经越来越多的应用到燃煤电厂脱硝系统中。但结晶问题却始终困扰着所有的尿素热解制氨装置。结合多家电厂处理实际运行中的尿素热解装置出现结晶的经验,着重分析了结晶产生的不同原因,并对部分样品进行了检测,分析了结晶样品的成分。探讨了预防结晶的对策,对尿素热解装置的设计和运行都提出了建议,以期能提高目前尿素热解制氨装置的运行可靠性。

Ammonia generated by urea pyrolysis is more and more widely used in SCR in coal - fired power plants because of its security advantages. However,the crystal issue becomes a real trouble for all the urea py- rolysis facilities. On the basic of experience from many urea pyrolysis facilities in running,the reasons how urea crystal is generated are analyzed, the crystal contents are analyzed after the samples tested. The countermeas- ures of how to reduce urea crystal are discussed and a series of advices is proposed in both designing and op- erating of the urea facilities. The target of the resarch is to boost the reliability of the urea pyrolysis system.