Results 1 to 15 of 15

Thread: "Leaking" Plate and frame filter

  1. #1
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088

    "Leaking" Plate and frame filter

    Howdy all,
    Ready for this?
    I'm filtering a kolsch 10bbl through a 40x40 plate and frame (24 plates) using Seitz K700 pads. The SV beer is clouded. Upon doing cell counts from the FV and the SV, I found almost identical values. Somehow the yeast is bypassing the pads, a.k.a. "leaking". I have several hundred successful filters using this exact setup producing beer I can read a newspaper through.
    Anyone else have experience with a "leaking filter"?

    Dave

  2. #2
    Join Date
    Apr 2006
    Location
    Ottawa Ontario
    Posts
    25
    Hi,

    Did this filter take any longer than usual? What was the differential pressures on the filter? Is this new yeast/ filter pads?

    Patrick

  3. #3
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088
    Filtration time is same as others, give or take. Diff pressure was approx 1-2 psi. New yeast (second generation), brand new pads.

  4. #4
    Join Date
    Mar 2007
    Posts
    27

    "Leaking" Plate and frame filter

    K700 pads are pretty loose. I think around 5-7 microns nominal. Our kolsch yeast is very powdery and required the use of K200 pads to produce clear beer. I think your pads were just not up to the job.

  5. #5
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088
    I have filtered over 350 individual batches of beer using K700, resulting in a beer I can "read a newspaper through". This cloudiness issue has just popped up. All other factors; process, equipment, pressures, recipe, temps, have stayed the same.
    Does anyone have any experience with their plate and frame filter (hardware) "leaking" beer from the sludge side to the filtrate side, seemingly by-passing the filter pads without using the fourth dimension?

  6. #6
    Join Date
    Apr 2005
    Posts
    44
    It couldn't be pad went in backwards was it?

  7. #7
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088
    Nope, two filters, three sets of pads. Insane attention to detail at that point. Pads went in correctly. I'm stumped.

  8. #8
    Join Date
    Mar 2003
    Location
    Pittston, PA.
    Posts
    155
    Are you sure the plates went in correctly? They didn't get shuffled around or flipped 180 degrees?

    After one of these filter runs, did the pads look clean/white or is there some yeast sediment on them?

    ---Guy

  9. #9
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088
    Okay, PADS WENT IN CORRECTLY! They were not flipped. I've eliminated the pads as a suspect.

  10. #10
    Join Date
    Mar 2003
    Location
    Pittston, PA.
    Posts
    155
    I didn't ask about the pads, I asked about the plates. Any chance they got shuffled around somehow?

    Also, after a filter run, do the sheets (pads) look like they had beer run thru them or are they clean/new looking? If they're still white there's your indication that somehow the beer was by-passing them.

    ---Guy

  11. #11
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088
    Sorry Guy,
    I'm more than a little frustrated by this. Nope, the plates were not flipped.
    The pads looked like they were just hydrated with no product through them.
    I do think the beer is bypassing them, BUT HOW is that possible? It seems to me that for the beer to get from the sludge side to the filtered side, it HAS TO go through the pads and yet, these filters I've done recently seem to have found a way around it! Slice away, Occam's razor!

  12. #12
    Join Date
    Mar 2003
    Location
    Pittston, PA.
    Posts
    155
    Well, if the filter is assembled correctly, with all gaskets/O-rings intact, in theory the beer can't bypass the pads.

    But that's just stating the obvious...

    If it were me and I were frustrated enough, I'd remove all but a couple of plates so the unit is down to 1 or 2 filter sheets. Then I'd pump some DE slurry or water/yeast slurry (no point wasting beer) through the filter. If it comes out clear, and visual inspection of the sheet confirms that the yeast or DE deposited on the sheet, then I'd start adding plates and sheets until the problem re-appears.

    If the problem occurs with only a couple of plates and only 1 or 2 sheets, at least you have fewer components to examine for problems.

    ---Guy

  13. #13
    Join Date
    Sep 2004
    Location
    Selah, WA
    Posts
    5

    Interesting...

    you may have a leaky plate/plates via loose screen to outlet or broken or split gasket/plate (I have no idea of your setup (DE to pad or pad only?) whether you are working with noryl or stainless plates, however some plates have screw fitted screen at the outlet that can loosen or crack in the case of noryl plates). I'm assuming all is good on your end, but just to put it out there for conversation...your final pressure differential seems to be a bit low (especially if pad filter only) which may indicate some yeast slippage (though this is more than slippage) and if you don't see a rise in your delta p over the run, then the pads are not filtering. I assume you have sightglasses on the inlet and outlet of your filter...a good flashlight will help you in determining if filtration is happening from the getgo. Sorry for your frustration, but it sounds as if blowby via low pressure differential or physical problem with plates, pads, or gaskets may be an issue. If these are all 'ok' then my last idea would be defective pads which I have come across on occasion. If you have already found the source, please let everyone know of the outcome. Final questions...did the pads get a good hydration (CO2 bubbles out of product stream?), see a pressure spike at anytime, and do you backflush the pads (assuming new pads there wouldn't really be a reason to backflush though it would depend on your beliefs in sanitizing a pad setup) prior to a run?

  14. #14
    Join Date
    Nov 2002
    Location
    Polson, Montana, USA
    Posts
    1,088
    This is a pad only set-up. I hydrate the pads externally and let sit for five minutes, then tighten down the press to approx 60-70% then front-flush with cold liquor and outlet valve governed back to generate ~2psi in the pad stack. Then I turn off cold liquor, tighten stack, begin product flow. I start pushing with about 10-15 psi on FV, SV is pressurized to about 8-10psi. I get normal product precipitation underneath the stack. These last filters started (first 50 gallons or so) clear, then the clouds rolled in and stayed for the remainder. Pressures never jumped, just a gradual climb in the filter to about 1.0 bar, product flow remained fairly constant.

  15. #15
    Join Date
    Sep 2004
    Location
    Selah, WA
    Posts
    5

    It all

    sounds good. From past experience, I've tried to keep the delta p at no less than 5 pounds for slippage reasons which would mean, if possible, feeding your plate with a variable freq. pump and umbilical your tanks CO2 (head pressure) to keep those pressures equal. Not that it matters, but what type of pad filter are you using (maker&number of plates)? Reading your reply it sounds as if you have a vertical plate setup which probably isn't the case. Noryl or stainless plates? It really sounds as if you have a perforated plate/gasket somewhere in your setup. Maybe try filling your pad filter with water (can add iodine for foaming). Get as much air out of the filter as possible (backpressure filter until all air has been removed) and then pressurize the filter to 1.5-2 bar using air/CO2 while keeping the outlet closed...you may be able to then isolate suspect plate(s) if the 'leak' is big enough. Just an idea.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •