Digester foaming 1

[JohnWeal]

Good Afternoon,

The client specifications require the biogas offtake to be a minimum of 1.5m above the sludge liquor level.

Has anyone on this forum experienced foam entering the offtake pipeline and if so, what are the consequences and remedial actions required?

The offtake pipework is DN200 with a maximum gas yield of 370 m3/h

Regards
John

 

[bimr]

On the last digester project, the gas outlet was in the center well of the gas holder, as high as possible. If the foam gets into the gas outlet, you may have a mess to clean up as the foam will be caught in the Condensate and Sediment Trap with drip trap. Foam out of the digester may clog gas handling equipment. A separate foam separator is also available to remove the foam.

We also installed a radar level instrument to measure the foam, a liquid level instrument to measure liquid level, a 3rd gauge to measure the level of the digester cover, gas flow meters, and viewing ports.

The following article describes the problems:

Foaming

Link 2

Link 3