尿素装置精馏塔循环加热器换热效率差原因分析及处理

摘要

介绍了二氧化碳汽提法尿素装置低压分解系统的工艺流程和精馏塔/循环加热器的结构特点；从工艺操作和设备等方面分析了精馏塔/循环加热器换热效率差的原因。结果表明：循环加热器列管结垢是造成精馏塔/循环加热器换热效率差的主要原因。通过采取相应的在线处理措施以及化学清洗和机械清理的方法，有效解决了循环加热器列管结垢的问题，满足了装置的运行要求。%Author has introduced the process flow of low pressure decomposition system in urea plant by carbon dioxide stripping and the structural features of rectifying tower /circular heater; has analyzed the reason of the poor heat transfer rate for rectifying tower and circular heater from aspects of process operation and equipment etc.Result indicates that the fouling for tubes of circular heater is the main reason causing poor heat transfer rate for rec -tifying tower /circular heater, the fouling problem is solved effectively for the tubes of circular heater by means of adopting appropriate online disposal measures as well as the chemically washing method and mechanically cleanimg method, it can meet the running requirement of the plant.