Liquid level fluctuation problem at the bottom of the pressure reduction tower
Thread Content
Recently, the liquid level at the bottom of the pressure reducing tower in our installation has always fluctuated. The differential pressure level gauge and float level gauge have fluctuated with different amplitudes. Even by adjusting the PID parameters of the liquid level control valve, the operation cannot be stable. We believe that the material inside the tower has irregular turbulence. However, adjusting the amount of the three-line reduction line has no effect on the control of the liquid level at the bottom of the tower. What do you think?
This problem really involves the core technology. Poor pulse disturbance will cause accidents. This pulse disturbance will appear in various parts of normal and vacuum pressure, and is caused by the imbalance of local balance. To find the reason, we need to expand the scope to find. For example, whether there is a pulse change in the temperature of the heat exchange terminal. The result will affect the smoothness of the residual oil. Is the steam injection in the furnace tube stable? Is the temperature too low? Is the tower inlet stable? Is the temperature of the middle section reflux back to the tower stable? Vacuum degree, etc.
I think the main influencing factors are: Vacuum degree, feed temperature, temperature gradient imbalance in the tower, and sudden increase in yield reduction (change in raw material properties). Affected by the above factors, the bottom-reducing residual oil cannot reach deep extraction, resulting in unstable pump volume. If you are originally very normal, there will be no bottom-reducing elevation. The elevation should not be less than 13.5m.
Sometimes the preheating valve of your backup pump for bottom reduction pump is opened too wide, and the volume of the bottom reduction pump may fluctuate, causing the bottom reduction liquid level to be unstable.