Conical Fv's and yeast removal help.

[Taps]

I am new to using conical fv's and all is great with temp control, fermentation.

But I am having a problem with the yeast (so4) as follows.

Fermentation hits FG, Dump yeast, Add finings then crashing the fermenters to 32 F over 24 hours, and settle for up to 5 days.

I slowly open bottom valve to dump yeast (a few times over days) until its bright. Hook up plate and frame to racking port, and start to filter.
(10bbls) Filtration runs well for about 7bbls then starts getting clogged with yeast.

It almost fells like the yeast cake is floating on the top or something???
Not really sure whats going on in there.
I have even tried running lots of bright from the bottom valve (but dont like watching the nectar go down the drain.

Until now we have been using dish bottom tanks with stand pipes and that worked great.

Any idea's?or advice would be fantastic.
Cheers

[kai]

S-04 is supposed to be a fairly flocculent yeast, so perhaps there are clumps holding onto the cone of your conical FV's? If you are yeasting off slowly and then trying to filter at a faster speed than you yeast off, that might be pulling these clumps of yeast off the cone and into your filter.

How does the beer upstream of your filter look as you are filtering? If you're seeing chunks of yeast flit by in your sight glass, then it likely is yeast being pulled from the cone.

If this is the case, what I would do is alter the yeast-off method. I'd do a couple of long slow yeast offs when beer is on-chill and fined, then when it looks more like yeasty beer than it does beery yeast, give it a few 'shocks' ie open and close the tank valve to let a few short high-velocity bursts of yeasty beer out. This is a good way to dislodge clumpy bits of yeast from the cone..., if this is your problem...

[JollyRodger]

Couple questions first. How are you adding the finings? How many sheets are in the filter? What micron are the sheets? somethings to try, use looser filter sheets, i use high micron and get bright beer. You should try to drop yeast again while filtering. The yeast maybe slipping down the cone as you filter beer out, see if you can drop more at about 5bbl before she sticks. Are you adding kettle finings? Also your mash and kettle ph play a big roll in yeast flocc, proteins, yeast health and ect.

[Poc]

Time and temperature are your friends when trying to drop out yeast. Though I would've thought 5-6 days at 32°F should be sufficient. We've a similar set-up for fermenting and filtering and generally the S-O4 is the best for getting beer through the filter without problems.

Have you tried letting it settle for more than 5 days? What happens when you backwash the filter? Are you able to get the rest of the batch through?

I'd second the suggestion of kettle finings. Maybe the addition of an extra few sheets if possible.

[gitchegumee]

JollyRodger has it, I think. I always use a sight glass pre and post filter. Seems that on some tanks, the yeast sticks a bit to the cone. When the beer level gets to the cone, the yeast dislodges and slides down to plug things up. Don't know how to solve this with P&F. I keep my DE filter pressure quite low during the run with loose perlite. When yeast chunks dislodge and come to the filter, I use all remaining body feed and slow down the beer flow rate to allow pressure to build slowly. Always manage to get the batch filtered in a reasonable time and with reasonable perlite doses. Except with Oatmeal Stout. Beta glucans bind up even loose perlite in that. Good luck!

[chaser]

Its probably just yeast sliding off the sides as you drain the fermenter. If your racking arm is movable then turn it upwards until the last possible moment, then start moving it downwards slowly as you start to reach the bottom of the tank. Avoid spending too much time with the racking arm pointing towards the sides of the tank though or you'll catch the yeast on the sides.

[Taps]

Thanks guys,
Yes makes sense that the yeast is sticking to the side of the cone, and when the beer level reaches the cone the clumps are dislodging and pumping straight to the filter.
I am now using 20 sheets Pall k700, but its just the sludge that cakes the filter, I manage to push the rest of the beer through, but at a real struggle.

The cones are polished but do have some small scratches, Yeast should be sliding down the cone, but I guess it is sticking to the cone.

Using kettle finings, also finings in the fv's, Method is connecting pump to bottom port and put finings into hose, then connect to racking port, bleed air and recirc pump for 15mins.....This method should work?

I will try dumping yeast with quick pulses over the week @32 and see how that works.
And post my results on the next filter run.

If all else fails I might install vibrating foot pads to the tanks