Centrifugal pumps for low shear application
Centrifugal pumps for low shear application
(OP)
I have a question to people who are working with pump selection for low shear applications. My area of interest is oilfield produced water treatment. This water usually contain small droplets of dispersed oil which is separated by hydrocyclones. But to use hydrocyclones effectively inlet feed has to have certain pressure. For this purpose a pump need to be utlized. The important aspect is not to shear dispersed oil even more.
I am aware that mainly two types are used for this purpose: positive displacement or centrifugal pumps. I am asking what are the parameters are used for the pump selection?
I am aware that mainly two types are used for this purpose: positive displacement or centrifugal pumps. I am asking what are the parameters are used for the pump selection?





RE: Centrifugal pumps for low shear application
I was checking that the better types of pumps would be a twin screw, a diaphragm pump (AODD would be typical) or a progressive cavity pump for such applications.
Your parameters would be the normal ones of flow and head / pressure requirement but also you're looking at low shear.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Centrifugal pumps for low shear application
The screw / centrifugal impeller with its open channel impeller design combines the gentle action of a screw pump and the high flow rates and cost efficiencies of a centrifugal pump.
https://www.environmental-expert.com/products/trit...
http://www.pumpengineers.co.nz/index.php/Pumping-P...
http://www.eng-tips.com/viewthread.cfm?qid=333207
RE: Centrifugal pumps for low shear application
RE: Centrifugal pumps for low shear application
From the link to the article you posted, it looks like not exactly area of my interest. Article talks mainly about non-newtonian fluids, where shear is damaging and irreversible. Applications also imply relatively low flow rates to reduce the impact. My interest is produced water treatment. I dont need to eliminate shear at all, but to keep it minimal, plus dealing with high flow rates.
Also regarding twin screw pumps, I have surveyd some reports form the operating companies, and some have challenges with them regaridng maintencance. In certain cases they have to do maintenance on them every second month.
I look for API 610/676 compliant pumps as a requirement in the petroleum industry. Couldnt find if this screw centrifugal type has such approval. Also it looks like these pumps can develop rather low pressure, not more 6-7 barg.
RE: Centrifugal pumps for low shear application
You provided NO DATA on your desired flow rate or pressure and only now say you want a "high flow" with no numbers. Your high might be my low. Same with pressure.
You appear to want to clean up produced water. This is usually done at low pressures and hydrocyclones don't like high pressures - it makes the exit nozzle very small and liable to clog.
API 610/676 is your choice, it is not mandatory. Smaller pumps and "special" pumps often do not follow the requirements of 610, but are still valid choices. If you want to restrict yourself to a smaller choice of pumps then that is your choice.
As the article says and George says - if you want to use a standard centrifugal then do so but at as low a speed as you can get (< 1000rpm).
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Centrifugal pumps for low shear application
I found interesting article where pumps comparison is given with regards to shearing:
https://www.spe.org/en/ogf/ogf-article-detail/?art...
Conclusion is also that at right conditions the centrifugal pumps can do well in water treatment aplications.
RE: Centrifugal pumps for low shear application
Depending on your flow rate - not given- have you looked at perastaltic(hose pumps)
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Centrifugal pumps for low shear application
No, I didnt look at this type of pump. My general input data is flow: 60 m3/h with differential pressure of 15 bar.
RE: Centrifugal pumps for low shear application
RE: Centrifugal pumps for low shear application
RE: Centrifugal pumps for low shear application
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Centrifugal pumps for low shear application
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)