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CasselBrewery
08-26-2015, 05:09 AM
Hi!

We've notice major biofilm development on the hot side (pre- hx). We wash with caustic and sanitize with PAA. It requires complete tear down from kettle to HX and scrubbing to get it off. We soften it with phosphoric/nitric cycle but it doesn't get it off. If tearing the whole assembly down every week is the only to do it is fine by me but with all the chemicals in the world I can't imagine their wouldn't be a product that will get rid of it without scrubbing.

Any suggestions?

Thanks!

gbrower
08-26-2015, 06:00 AM
When you say biofilm do you mean the protein and mineral deposits on your kettle?

If so then you need to do an acid cycle first for about 20 minutes. You should have most of it come off in flaky leaf like parts. If it comes off then stop they cycle and if not run for another 5 minutes. If it has built up a lot then you might be clogging your spray ball. If so then you might need to rinse it down the drain and run one more cycle. We like to double dose our acid so we do 2 oz per gallon.

After this you will still have a line around the kettle and a few spots but not much else for junk. If you do have a lot of protein spots then it will lower the ph of the caustic and make cleaning not as effective. Most chemical providers will provide you with a ph test kit for free if you ask for it to see if your product is in effective cleaning concentration. You should use a chlorinated caustic. I know the "dangers" of chlorine but after 10 years of chlorinated caustic cleaning we have had no issues. I have also tried a ton of none chlorinated caustics and they just don't do the job. I suggest afco 5236 for effectiveness and cost.

CasselBrewery
08-26-2015, 06:33 AM
When you say biofilm do you mean the protein and mineral deposits on your kettle?

If so then you need to do an acid cycle first for about 20 minutes. You should have most of it come off in flaky leaf like parts. If it comes off then stop they cycle and if not run for another 5 minutes. If it has built up a lot then you might be clogging your spray ball. If so then you might need to rinse it down the drain and run one more cycle. We like to double dose our acid so we do 2 oz per gallon.

After this you will still have a line around the kettle and a few spots but not much else for junk. If you do have a lot of protein spots then it will lower the ph of the caustic and make cleaning not as effective. Most chemical providers will provide you with a ph test kit for free if you ask for it to see if your product is in effective cleaning concentration. You should use a chlorinated caustic. I know the "dangers" of chlorine but after 10 years of chlorinated caustic cleaning we have had no issues. I have also tried a ton of none chlorinated caustics and they just don't do the job. I suggest afco 5236 for effectiveness and cost.

No as far as the kettle is concern we use Zep Lac 45 which is phosphoric acid and the kettle comes out spotless.

What I was referring to is a thin film inside lines including hoses that has a copper/gold color. Here's a picture https://drive.google.com/file/d/0B71_pRRwpZ73NmxNWFFpQnVhaEk/view?usp=sharing This occurs only on the suction line -> pump -> line to HX. Obviously the cold side is fine.

gbrower
08-27-2015, 07:06 AM
Do you run a hose to your hlt or is it hard piped? You really shouldn't be getting buildup like that. I would look at maybe trying some different chemicals or changing your cleaning regiment. Chem providers will be more than happy to send you free samples.

Mike Elliott
08-27-2015, 07:38 AM
We use Loeffler Chemical, and they recommend the occasional use of an extra oxidizer (lerasept-o, I think it's called) along with caustic. Since we started that, the hot side has been perfectly spotless.

Couple it with a run of a good phos/nitric blend weekly or so and your film won't stand a chance.

CasselBrewery
08-27-2015, 09:32 AM
We use Loeffler Chemical, and they recommend the occasional use of an extra oxidizer (lerasept-o, I think it's called) along with caustic. Since we started that, the hot side has been perfectly spotless.

Couple it with a run of a good phos/nitric blend weekly or so and your film won't stand a chance.

Thanks Mike! Will contact our chemical suppliers to find an equivalent

Matt Falco
08-27-2015, 02:10 PM
What strength caustic solution are you using? Bump it up to 4% and see if that helps... You should not need to scrub. Cycle at 160 deg F.

CasselBrewery
08-27-2015, 02:26 PM
What strength caustic solution are you using? Bump it up to 4% and see if that helps... You should not need to scrub. Cycle at 160 deg F.

Using 2% for now we could bump it up and see how it goes. After the brewday from yesterday the biofilm hasn't come back so this tells me its over a certain period of time. Strong oxidizer after X brew would be good I think.

CasselBrewery
08-27-2015, 02:28 PM
Hey Mike, so you add the lerasept-o to the caustic mix? Or run it separately?

campbell.brian
09-18-2015, 11:45 AM
Your picture is a classic example of organic deposits. Acids will not be nearly as effective at removing these soils as an oxidative alkaline cleaner.

I recommend either a chlorinated caustic (do not exceed 145F) or even better, a non-chlorinated caustic with a non-chlorinated oxidizer such as the aforementioned LERASEPT O. If you are unable to change vendors, a highly concentrated Hydrogen Peroxide (30-50% H2O2) will work nearly as well.

Our recommended regimen to customers is:

Caustic (built) 0.3 - 0.8% by NaOH
LERASEPT O - 0.5% by volume
160-180F (70-80C)
15-30 minutes, followed by a potable water rinse

Remember to add products to the solution and not to each other. Always add chemical to solution, never solution to chemical nor chemical to chemical.

Buckley
09-18-2015, 02:53 PM
Your picture is a classic example of organic deposits. Acids will not be nearly as effective at removing these soils as an oxidative alkaline cleaner.

I recommend either a chlorinated caustic (do not exceed 145F) or even better, a non-chlorinated caustic with a non-chlorinated oxidizer such as the aforementioned LERASEPT O. If you are unable to change vendors, a highly concentrated Hydrogen Peroxide (30-50% H2O2) will work nearly as well.

Our recommended regimen to customers is:

Caustic (built) 0.3 - 0.8% by NaOH
LERASEPT O - 0.5% by volume
160-180F (70-80C)
15-30 minutes, followed by a potable water rinse

Remember to add products to the solution and not to each other. Always add chemical to solution, never solution to chemical nor chemical to chemical.

I use Brian's method with the Chemicals recommended. For days that the caustic doesn't cut it by itself. Sometimes I have to turn the kettle on for a short period to get the solution n the recommended temp range but it makes a pretty big difference on the heavy soil build up.