Pump Transfer solutions for residual bulk removal in transfer line

[pradeepbarola]

QUERY/PROBLEM(refer to the attached file)

Bulk is transferred from location A to B using a centrifugal pump. At the end of operation(when there is no bulk at the pump suction), bulk remaining in the discharge line(marked by Red) causes problem for the next batch(As next batch is of different product).

I need your suggestions on how to remove this remaining bulk to some satisfactory level ?
P.S.: There is no facility for cleaning the line after batch operation.

 

[Graniar]

My suggestion is to pump compressed air into tank A instead of using centrifugal pump in between.

 

[pradeepbarola]

Thanks for the reply.
I did calculations for the line losses & pump head required.

for
1" line, 5 m3/hr, head required is 41m
1" line, 3 m3/hr, head required is 21m
2" line, 5 m3/hr, head required is 10m

I think air would not be able to provide that high pressure for transport.

 

[Graniar]

Anyway, current installation has only one pump, and has to produce the same pressure difference.
For 41m pipe, Reynolds number 75000, turbulent case, by quick calculations I got about 50 bar.

It may be usefull to use two different compressors. On finishing, depending on surface tension, some substance will remain on the pipe walls, and will be moved forward by the air flow. It will require less pressure, but higher flow rate.

 

[chemisttree]

.. and this little piggie went "whee, whee, whee, whee, whee," all the way home.