PBW question

[Rictanica]

Hello BN'ers!
I recently listened to the old session sanitation show and a question about PBW.

I buy it at my LBS, and use it sparingly due to it's price. They mentioned you could reuse it in that show. I have always just poured it down the drain after every use. It states on the lable to use it at least 100f. I guess due to the film it's supposed to leave at lower temps. Do you just need to rinse with the same temp water used to clean equiptment, or does it keep working at all temps and rinse it at the temp it drops to?

[Hoppy Brewah]

I use PBW with hot water and rinse with hot water. If I have a carboy with lots of old krasuen stuck to it, I will let it sit overnight and then scrub it the next day and rinse with hot water. I would say always rinse with hot water to get the PBW (alkaline) off before using starsan (acid) to sanitize.

[thatguy314]

Hello BN'ers!
I recently listened to the old session sanitation show and a question about PBW.

I buy it at my LBS, and use it sparingly due to it's price. They mentioned you could reuse it in that show. I have always just poured it down the drain after every use. It states on the lable to use it at least 100f. I guess due to the film it's supposed to leave at lower temps. Do you just need to rinse with the same temp water used to clean equiptment, or does it keep working at all temps and rinse it at the temp it drops to?

I find that it needs to be rinsed with the SAME temp as the PBW. it only leaves a film if the PBW is hot and you rinse cold. I regularly make a dilute PBW, let it sit overnight and rinse it with little to no residue. Still hot water works better.

With regards to reusability. PBW is 3 things:
1) Oxygen-reagent (percarbonate) which is basically dehydrated hydrogen peroxide. when it reacts with water you'll get oxygen formation. this will eventually run out, and you will lose this activity
2) surfactant - a compound that lowers the surface tension of the liquid. they describe it as making the water"more wet" but what it actually does is it makes water stick to itself less, so it doesn't form menisci. Have you ever noticed how water curves on the top of a glass or forms beads? this reduces that so it spreads itself out better over surfaces.
3) chelators: compounds that pull metal ions out of solution, and help break up salt deposits. these in theory could be spent, but i doubt they will be affected very much by most tap water.

So you can use it continuously, but it will lose some activity.

I tend to find if you m ake it up to an appropriate concentrationa nd you don't have too much gunk, it does it's job within 30 minutes or so. Generally it's still hot and I can transfer it to another container that needs cleaning (e.g., 2 carboys).

Hope that's helpful

[Rictanica]

thanks hoppy and guy. Iv'e spent a lot of dough on that stuff.

[lunitick1976]

Thanks for asking man I had this same question, I was going to post but decided to search it first. good info guy's.

[thatguy314]

thanks hoppy and guy. Iv'e spent a lot of dough on that stuff.

You can buy a cheap oxyclean and toss it back in if you want to get the oxygen activity active again. It's like 1/5 the price of the PBW.

Very often I mix it with PBW 50/50 to make the pbw last longer.

[Rictanica]

thanks hoppy and guy. Iv'e spent a lot of dough on that stuff.

You can buy a cheap oxyclean and toss it back in if you want to get the oxygen activity active again. It's like 1/5 the price of the PBW.

Very often I mix it with PBW 50/50 to make the pbw last longer.

nice idea. I have seen, on other forums in the past, where folks mix TSP and oxyclean. Its supposed to be close to PBW, but I would probably poison my family if I tried mixing chemicals....

[krizwit]

I generally try to clean several things at once, generally multiple kegs or carboys. You dont need to use as much as is prescribed if you get the surface looking clean before you even put the PBW in. In other words, I will use a carboy brush to get my carboys looking clean and then I add a little PBW with hot water and let it sit for 10-20min. I havent had a problem and I am saving myself some coin and not putting so many chemicals down the drain...