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Staining/Deposits after caustic CIP

  • 1.  Staining/Deposits after caustic CIP

    Posted 07-26-2022 17:54
    Hello,

    I keep getting these stains/deposists after running a caustic cycle and then rinsing. The only way to remove them is to physically scrub them with acid on a sponge. I have tried many things to resolve this issue but can't figure it out. Please let me know if you have seen this before or if you are able to point me in the right direction.

    Thank you,
    Zach


    ------------------------------
    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
    ------------------------------


  • 2.  RE: Staining/Deposits after caustic CIP

    Posted 07-26-2022 21:34
    Hi Zachary,

    That looks like classic silica deposits to me.  Acid CIP will not remove it.  It takes a lot of hot caustic to remove them.  I wrote an article on how to remove Biofine Clear or Nalco 1072 deposits and it can be seen here:

    https://www.birkocorp.com/wp-content/uploads/2018/12/TechnicalQuarterly.pdf

    Hope this helps!

    Dana

    ------------------------------
    Dana Johnson
    Technical Director, Craft Brewing
    Birko - A Diversey Company
    Henderson CO
    (303) 289-1090, ext. 117
    ------------------------------



  • 3.  RE: Staining/Deposits after caustic CIP

    Posted 07-27-2022 10:15
    Hi Dana,

    We don't use Biofine or anything like that....

    ------------------------------
    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
    ------------------------------



  • 4.  RE: Staining/Deposits after caustic CIP

    Posted 07-27-2022 13:36
    I have seen something similar when the interior lining of brewers or vintner hose break down. We found a citric degreaser with a soft brush was the best at removing the deposits. You may be able to tell if the hoses are compromised by visual inspection of the hoses, or by rubbing a finger inside the hose while damp and see if any particulates come off.

    ------------------------------
    Ryan McVeigh
    Brewery Operation Manager and Brewmaster
    Kona Brewing Co
    Kailua-Kona HI
    (808) 443-1800
    ------------------------------



  • 5.  RE: Staining/Deposits after caustic CIP

    Posted 07-27-2022 19:11
    Ours hoses are pretty new, probably a year max.

    They all look and feel fine from what I can see.


    ------------------------------
    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
    ------------------------------



  • 6.  RE: Staining/Deposits after caustic CIP

    Posted 07-27-2022 13:37
    Hey Zachary,

    Can you tell us a bit more about the components of the caustic you are using? Regimen for acid washing and re-passivation of tanks? Also curious about the characteristics of the water you use.

    Beers,

    Aaron

    ------------------------------
    Aaron Brodniak
    Consultant
    Edmonds WA
    ------------------------------



  • 7.  RE: Staining/Deposits after caustic CIP

    Posted 07-27-2022 19:11
    It's standard caustic from Chemstation. I don't have the actual data on what its made up of. It's product 50177.

    We passivated the tanks using the Birko method originally, acid cip every quarter or so.

    I can post our water report but it's fairly neutral.

    ------------------------------
    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
    ------------------------------



  • 8.  RE: Staining/Deposits after caustic CIP

    Posted 07-28-2022 18:51
    Hi Zack
    I can't look up the Chemstation product online, is it a chlorinated caustic?   I'm wondering if you are warm rinsing the tank after cleaning then the chlorine or even the caustic salts are drying onto the side of the tank as the rinse water evaporates?    I could see chlorine or some other additive in your chemical "burning" the stainless if its drying on the surface and then it would be very difficult to remove.     The discoloration also reminds me of chlorine damage we've seen from using chlorinated city water during CIP, I would make sure you are carbon filtering all of your water

    Is the stain the same shapes and in the same exact locations every week?    You could try another brand of caustic for a week or two or you could try rinsing with acidic water  after your caustic cleaning and see if the problem goes away completely.

    ------------------------------
    Curtis Holmes
    Alaskan Brewing Co
    ------------------------------



  • 9.  RE: Staining/Deposits after caustic CIP

    Posted 07-29-2022 10:13
    Hi Curtis,

    We do not use chlorinated caustic, we do rinse with HLT water which is around 195F.

    The stains are not the same shape or in the same spots. They are random and sometimes they are a ring around the bottom of the cone.

    ------------------------------
    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
    ------------------------------



  • 10.  RE: Staining/Deposits after caustic CIP

    Posted 07-29-2022 14:13

    It looks like it could be Calcium Oxalate.  The best results removing that type of Scale is an MSA based acid.  It's the same type of acid that is used in cleaning under pressure, Methane Sulfonic Acid.  Common acids using Phosphoric/nitric acid  blends, are not effective against this type of scale.rochester Midland has a product HDA6600 for use in removing Calcium Oxalate, and cleaning under pressure, particularly unfilter products.  Perfect of conserving CO2 during these shortages.  

     

    Sent from Mail for Windows

     






  • 11.  RE: Staining/Deposits after caustic CIP

    Posted 07-29-2022 18:28
    Hi Zack,
    That is a very hot rinse for a tank.  Aside from putting a lot of stress on your tank welds and cooling jackets due to the high heat expansion that stainless has, the water will evaporate off the surface very fast when you quit rinsing and could be leaving chemical deposits behind.  I would keep around 100-120 degrees for your caustic and your rinse water at most, or slowly bring the rinse water temperature down at the end of rinsing so you finish with cool water and see if that helps!

    ------------------------------
    Curtis Holmes
    Alaskan Brewing Co
    ------------------------------



  • 12.  RE: Staining/Deposits after caustic CIP

    Posted 08-01-2022 17:53
    I would try keeping the cleaning and rinsing temp in the 160-180 d. F. range and see if it helps.  195 d. F. water may indeed be be causing the issue as Curtis pointed out.

    Dana

    --

    Dana Johnson

    Technical Director, Craft Brewing | Birko - A Diversey Company

    C: 720 346 1562

    P: 303 289 1090

    dana.johnson@diversey.com

     

    www.diversey.com

    www.birkocorp.com

    9152 Yosemite Street, Henderson, CO 80640

      

    This e-mail is intended for the exclusive use of the recipients named above and may constitute confidential or proprietary information.  If you have received this e-mail in error, please notify me immediately by reply e-mail or telephone and completely delete or destroy any and all electronic or other copies of the original message and any attachments to it. Thank you for your cooperation.







  • 13.  RE: Staining/Deposits after caustic CIP

    Posted 07-27-2022 13:38
    Zack

    This may be the start of chlorobutyl breakdown in your hose. Not sure how old your hoses are but this could be the issue. It's very hard to get off of stainless steel. I high concentrate citric acid may help.


    ------------------------------
    Rob Williams
    Sales Manager
    Alliance Hose & Rubber
    Elmhurst, Il
    708-932-8386
    rwilliams@alliancehose.com
    ------------------------------



  • 14.  RE: Staining/Deposits after caustic CIP

    Posted 07-28-2022 13:41
    Did you try an acid cycle?  If so when was the last time you ran acid?   Looks like salt build up from what I can see.  The Chemstation caustic has done something like this to us when we used to use it and we found that we needed to rinse immediately and not let the caustic dry at all on the tank.  We had to run a powdered alkaline cycle to get it off.   Just some thoughts

    ------------------------------
    Landon Swanson
    Head Brewer
    Pueblo Vida Brewing
    Tucson AZ
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  • 15.  RE: Staining/Deposits after caustic CIP

    Posted 08-19-2022 09:29
    Update: I think I solved the problem by running the caustic and rinse cycles at a lower temperature, around 130F.

    Thanks for all the input.

    ------------------------------
    Zachary Gordon
    Old Thunder Brewing
    Pittsburgh PA
    ------------------------------