摘要
用显热加热重沸器已被广泛应用于石油化工装置,但如果设计不当,也会造成重沸器温度控制的失败。某催化汽油加氢脱硫装置,其稳定塔重沸器采用高温工艺流体作为加热介质,塔釜温度由设在加热介质主管线上的主调节阀和旁路线上的压差调节阀共同控制。但开工初期塔釜温度难以控制,其原因主要有两个:一是重沸器加热介质流量小,且在不稳定的过渡沸腾区操作;二是旁路调节阀两侧的管路压差过大。改进措施主要有:适当降低稳定塔的操作压力,并增加主管线上加热介质的流量,减少旁通线流量,使重沸器完全在稳定的泡核沸腾区操作;将稳定塔温度控制改为三通调节阀控制,以避免旁路调节阀两侧的压差测量值不能准确反应主调节阀的压差变化,从而导致控制的紊乱。上述措施实施后,稳定塔釜温控得到明显改善,且产品质量合格。
The method of using sensible heat to heat re-boilers has been widely used in petrochemical units.If designed improperly,however,the method may also lead to a failure of temperature control for the re-boiler.The stabilizer re-boiler of an FCC gasoline hydrodesulfurization unit uses fluids from high-temperature processes as the heating media and the temperature in the stabilizer kettle is jointly controlled by the primary regulating valve on the primary heating medium line and the pressure difference valve on the bypass line.In the early stage since production start,the temperature of the kettle was difficult to control due to two factors: firstly,the flow rate of the heating medium for the re-boiler was too low and the operation was in the unstable transition boiling range;secondly,the pressure difference between the piping on the two sides of the bypass regulating valve was too large.Countermeasures taken included:properly reducing the operating pressure for the stabilizer,increasing the flow rate of the heating media for the primary piping and reducing that for the bypass line to enable the re-boiler to work within the stable nucleate boiling range;introducing three-way regulating valves in temperature control for the stabilizer to prevent control disorders due to the inability of the pressure difference measurements from the two sides of the bypass regulating valve to accurately reflect the changes in the pressure difference on the primary regulating valve.As a result of the above measures,the temperature control for the stabilizer kettle improved considerably and products produced met required quality specifications.
出处
《中外能源》
CAS
2012年第1期88-91,共4页
Sino-Global Energy
关键词
重沸器塔釜温度控制
泡核沸腾
过渡沸腾
三通调节阀
Re-boiler temperature control for stabilizer kettle
nucleate boiling
transition boiling
three-way regulating valve