Regarding the issue of the pump often running dry
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My unit is equipped with a residual oil stripping tower, which uses low-pressure steam to strip the light components from the residual oil; operations are carried out under negative pressure. Although we regularly drain water from the bottom of the tower, the pump at the bottom of the tower still often gets emptied. Do anyone have any suggestions?
1. The inhalation height is low. 2. The pump seal is not good. 3. The amount of stripping steam is too high.
It’s probably because the amount of stripping steam is too high; this has happened in our unit as well
The temperature at the bottom of the tower is too high; either the suction height of the pump is too low, or the pump wasn’t designed properly by the design team. Cooling water can be added to the pump!
Thank you all; the temperature at the bottom of the tower is controlled at 98 degrees. Can excessive stripping steam also cause evacuation? It doesn’t seem that big. At present, we all believe that the reason for the interruption is mainly the excessive amount of water in the tower bottom; therefore, the measures taken are 1. to enhance drainage. 2. The temperature at the bottom of the tower should be no lower than 98 degrees, but evaporation still cannot be avoided
What is the boiling point of the residual oil at a constant negative pressure? Is a temperature of 98 degrees higher than the boiling point of the light components in the residue at the operating pressure (is the residue supposed to be a mixture?) ）? If this limit is exceeded, it may cause the light components to vaporize, leading to pump cavitation. In such cases, the vacuum level can be reduced within the limits permitted by the process, and the tower pressure can be increased slightly to see if that helps. Another possibility is that the stripping effect is insufficient, resulting in the light oil not being fully stripped; this issue can be resolved by increasing the amount of stripping steam or raising its pressure. It’s also important to check whether the distance between the bottom extraction point and the pump inlet meets the requirements for pump installation, and whether the height difference is greater than the vaporization pressure of the medium. Finally, check for any leaks in the pump’s seals, as well as any other equipment-related issues such as leaks in the pump’s cleaning systems. I hope this helps you resolve the issue soon!
Thank you, I’ll figure it out through practice
Personally, I think what was said on the 6th floor makes sense.
The poster might want to check the pump’s inlet pipeline; in many cases, pumping failure is caused by leaks in the inlet pipeline
Drain from the tower bottom? What does it mean?
The question isn’t clear, so it’s difficult to answer. Simply reduce the flow at the pump’s inlet; that should do it