3 replies to this topic

[NOEC]

Hi everyone,

I've been asked to help resolve a solids build-up issue in a sump that collects a slurry stream from the plant's river water clarifiers. The sump pump has been experiencing reoccuring problems because the solids have been collecting around the suction eventually covering the suction bell. In order to prevent the solids from settling, I'm conisdering installing an agitator or a liquid/liquid sparger system at the bottom of the sump to suspend the the solids in the water. Does anyone have any recommendations for one over the other? I'm concerned that the sparger system could become plugged from the solids in the sump. Does anyone have any sparger design literature? Instead of a gas, I plan on using a nearby cooling water stream as the sparger agitation medium. Any information would be greatly appreciated.

Thanks,

Eric

[tarafdar]

Hi,
you can divert a stream from the discharge line of the pump to pump suction.This will prevents the solids from settling there.

[kkala]

A sketch indicating sump dimensions and location of pump (vertical, or horizontal at sump site) would be useful. In a past ferilizer industry there were a lot of sumps with suspended solids (usually gypsum) and horizontal pumps, activated by on/off level control. Agitators were an effective way to homogenize that slurry, see http://www.cheresour...h__1#entry49693. Mentioned reference of Chemical Engineering supplies design method for homogenizing suspended solids to the extend nedded. Alternatively you can address to agitator suppliers.
In case that the pump is vertical and the sump rather small, there may not be enough space for an agitator. We had lateral agitators too (smaller size), but these had problems of leakage. Probably it is practical to direct some of the flow from pump discharge to the sparger. Vertical pump is assumed to be in intermittent operation, so that extension of operating time due to some recycling does not create any real problem. I would try to direct a flow rate to sparger equal to pump minimum flow, so that I can operate the sparger even when there is no need of liquid transfer.
I do not have experience on spurger design and how to "avoid" scales and plugging.

[NOEC]

Attached is a sketch of the sump dimensions with the pump location. The suction basin for the pump is approximately 4' below the sump floor. The pump is a Hazleton Vertical Slurry Pump. Currently, there is a separate line diverted from the pump discharge to the pump suction area, but it doesn't seem to have prevented the solids from settling. Does anyone have literature that approximates the amount of sparger liquid needed to agitate X amount of cubic feet? I ask this because given the sump volume (25 x 25 x 15), I don't think directing some of the pump discharge to a sparger system will provide the necessary amount of fluid to provide adequate agitation. Thanks for all the help.

Eric

Attached Files

•  2011082410253999.pdf   89.04KB   39 downloads