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Positive Displacement Pumping System

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I_B

Chemical
Jan 30, 2018
1
Good morning

We are exploring the possibility of replacing centrifugal pumps with positive displacement pumps for a slurry pumping operation (SG > 1.5 @ static head of 60m). One of key operational issues experienced with the centrifugal pumps arise after power dips/loss, resulting in production loss due to line desanding. How does a positive displacement pumping system react after a power dip/loss (desanding time, pressure build-up risk, etc.)?

Kind regards
 
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I'm wondering why you would expect the slurry line's behavior to change.



Mike Halloran
Pembroke Pines, FL, USA
 
Not easy to judge based on yr description but there probably won't be much difference on loss of power as this is a slurry fluid transport issue, not determined by the pump type.

The potential for a high pressure developing for a PD pump is larger and flow control is different. If a brief burst of more pressure over the normal operating pressure would result in a faster re-start isn't clear, but then the pump and motor would need to be sized for that condition.

The two types are fundamentally different so you need to understand why one works or doesn't work and also what type of PD pump. Piston or reciprocating can introduce pulsation and vibration where you don't have it now.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
There may be a good reason for the centrifugal pumps you've got now - these have wider flow paths within the pump while pd pumps (gear or screw)have much narrower flow channels. So if the solids in this slurry are abrasive (it sounds like you've got sand, which is very erosive), you may suffer high erosion / metal loss, perhaps even resulting in seizure on startup. Fix this transient power dip problem instead.
 
Why are you losing power? Is it a source problem or is the motor tripping the breaker?

-Blake

"If it rotates, it vibrates."
 
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