Don't add chemicals to hot water???

[Sir Brewsalot]

Just got off the phone with my chemical supplier, who made a strong recommendation to me: Don't add chemicals to hot water. Instead, add them to ambient water, and heat them up to operating temps.

This was a new one to me - has anyone ever heard of this before? And do you follow this recommendation?

I'm no chemist, but what's the thinking here?

Thanks,
Scott

[Jephro]

I have seen some explosive reactions adding chemicals to hot water. Once with a Five Star caustic, and once with i think a nitric acid. Never had a problem with the chemicals i use now, but better safe than sorry.

I think i remember reading on the Five Star label that you can add hot water to the chem but not the chem to the hot water but dont quote me on that.

[tarmadilo]

Never had a problem adding chemicals to hot water, but I have to say that the water was usually in some kinda tank or kettle, often being circulated, and I was always wearing goggles and gloves...

Cheers, Tim

[crassbrauer]

cool and slow

When sodium hydroxide dissolves in water, heat is given off AND solid sodium hydroxide becomes freely mobile in the water. This occurs very rapidly leading to a violent reaction. Hence, on the MSDS of most caustic sodas, it states: "Adding water to caustic solution generates large amounts of heat." The hotter the water, the more violent the reaction. A guy from my home town lost his sight because he added sodium hydroxide powder too quickly to water. Take home message: Add it slowly and add it to cool to lukewarm water.

[BeersmithMT]

I would have to believe that your chemical supplier is referring specifically to caustic soda. The explosive reaction between dry Sodium Hydroxide and water is one reason why we have always used Five Star PBW instead - it is much more people friendly. We have never had any issues with directly adding PBW to water or vice versa. As with any dry powder however, there is some inhalation risk.

[mr.jay]

I'm with Tarmadilo on this one. Take precautionary measures, and add slowly to moving hot liquid.
If I waited for my water to heat up everytime I clean something (P.S. how do you heat your water in a glycol cooled FV that doesen't have a heat source?)I've never had a problem (Thank God), but I treat that stuff like it's...well, like it's causic. Remember what you learned in Chem class, never add water to a chemical (especially an acid) and always wear googles and gloves.

[Ted Briggs]

googles

Mr Jay
I thought I had all the safety equipment I needed...can you tell me where to buy a pair of googles??

[Jephro]

LSS.com "Lab Safety Supply"
Thats where i got my boots, glasses, Leatherman and PH meter.

[Sir Brewsalot]

Ted, if I were you, I'd try searching on www.Google.com...and then again on www.Google.com. (It's plural, right?)

Yes, it's PBW not caustic, and that was still the recco.

"how do you heat your water in a glycol cooled FV that doesen't have a heat source?" - INDEED! That's my question... heat it in a dedicated water heating, chem storage tank? Not quite sure we've all got those kicking around.

Thanks for the help everyone.

Cheers,
S

[Greenbrewmonkey]

Hello All,

Following the thread a little off topic, you can build a spiffy little hot (or cold) chemical at cleaning concentration holding tank in an old keg, or any stainless drum (if you need more than 15 gal of solution at a time). I took an "extra" converted Hoff Stevens, welded in a threaded piece on one side and a long stem sanitary tri clamp fitting on the other. Set it on a stand fitted with castors, threaded in an electric heating element, wired it up, and whammo. Portable chem tank ready for use.

Cheers,
Ron
Jolly Pumpkin Artisan Ales

[hoprocketeer]

Chemicals to hot water

Good advice from jolly pumpkin. On the pub side we felt it best to save as much chemical $ as possible. We used a 55 gal. ss drum, with an 3" extension place 3" off the bottom of the tank, to allow any sludge to settle. We would then place an immersion heater throught the bung on the drum top to heat the chelated sodium hydroxide to 150 degrees. We would then test this every time we used it and dose it up to around 3% Naoh, using 50% chelated caustic from our local chemical supplier. The caustic for dosing would be added directly to the kettle during whirlpool cleaning cycle, an easy addition. Others have been correct in noting that adding caustic to water creates problems through chemical reactions and intensified heating. After our cleaning cycle, we would then recapture our caustic back to the tank and hold it there until our next cleaning cycle. Don't for get to turn off the element when emptying the tank!!!!!

cheers...