延迟焦化装置分馏塔结盐原因分析及预防措施

Analysis of causes of salt deposition in fractionation column of delayed coking unit and prevention

延迟焦化装置原料复杂,氮、氯含量高,造成分馏塔顶部结盐现象频发,严重影响装置的平稳运行。为解决分馏塔结盐问题,分析了分馏塔结盐的原因,并提出了结盐后在线汽油洗塔盘及水洗塔盘的解决方法。针对运行过程中防止分馏塔结盐现象发生,采取了分馏塔顶降温除盐、分馏塔顶提温除盐、加注结盐控制剂、在线洗涤除盐等预防措施,有效地缓解了分馏塔结盐的现象,延长了装置的运行周期。

The feedstock of delayed coking is very complex and contains the high contents of nitrogen and chlorine, leading to the salt deposition at the overhead of fractionation column frequently, which seriously affects the smooth operation of unit. To solve the problem of salt deposition in the fractionation column, the causes of salt deposition are analyzed, and online gasoline washing and water solution washing of trays after salt deposition are recommended. To prevent the salt deposition in the fractionation column during the running operation, preventive measures have been taken such as lowering and raising the temperature of the overhead of fractionation column, adding salt control agent and applying new desalination technologies to remove the salts. All these have effectively mitigated the salt deposition in the fractionation column and extended the unit＇ s operation cycle.