What is the purpose of these vacuum drums at pump suction 2

[Iomcube]

Can anyone explain the purpose of these small drums at pump suction. What doesn't the vendor simply use submerged pump suction directly.

https://files.engineering.com/getfi...e=Screenshot_20221230_104300_DWG_FastView.jpg

https://files.engineering.com/getfi...e=Screenshot_20221230_104329_DWG_FastView.jpg

 

[LittleInch]

I think they are there to ensure that the pumps always have flooded suction. They look like centrifugal pumps which don't normally self prime.

With that extra line it might also be to start the stem on a more dilute mixture.

Slurry is quite odd stuff so there could be another reason.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[pierreick]

Hi,
Google "priming pot"

https://www.munsch.de/en/products/priming-pot

Pierre

 

[georgeverghese]

The agitator in the source tank entrains gas in the bulk liquid so this gas has to be separated. The priming pot seems small - the suction line to the pumps should be continuously sloping down to the pumps, so that residual gas in the exit from the priming pot gets to escape back into the priming pot. Else you will still lose prime at pump suction. Agreed, a free venting arrangement of the inlet and exit nozzles on the pumps will also be necessary to keep the pump casing primed. Presume the vent line on the priming pot returns somewhere where the pressure is lower than that in the priming pot?
Submerged pump alternate may have been rejected on the grounds that solid salt granules could get into pump suction, eroding the impellers ?

 

[LittleInch]

I don't think it's a normal vent as it needs to lift the slurry so would normally operate less than atmospheric pressure.

You need to find the operating philosophy but could easily be just there to fill the drum with water to prime the inlet system or flush out the piping if it gets clogged.

Or maybe fill the inlet pipe during shutdown to stop it clogging up.

Looks very manual though.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Iomcube]

Exremely thank you all for the comments. Will the vent valve will be closed during operation? I am new here so I just am learning peoples language & observing stuff. Its a chloralkali industry soon I will get more details.

 

[pierreick]

Hi Iomcube,
Yes of course the vent valve is closed during operation otherwise you will lose the priming.
You should notice the absence of foot valve to prevent the clogging with solid.
Good luck
Pierre

 

[ProSafPlant1]

I think the schematic is misleading. The brine stream likely over-flows as effluent from the top of the settler / clarifier to the pump suction tank, not from the bottom where the solids are settling out.

 

[Iomcube]

Thanks for the answers.
ProSafPlant1, nowadays clarifier / settlers are substituted by ceramic filters. Yhe waste moves to some sort of press filter which produces sludge cake finally.