% of Salt Solution for freezing

I don't have the amnswer but have a question.

From what I can remember salt lowers the melting point of ice. So my question is what is the benefit of having ice melt below 0 degrees C?

R.

A reply to Robak, the salty water or "brine" in A/C or refrigeration system is simply a medium to move the heat from one point to another . eg in a large system the cost of refrigerant (freon) would be huge because of the volume required therefore chill the brine and pump it to the desired location for whatever purpose.
Cheers Dave L.

Off course once you do that to it you can't drink the water either though. In 90% of cases it's probably not an issue - but if you broke down in a remote dry area and needed to wait a few days for help it might be.

Dave

I used to use "brinies" two litre milk containers, when going deep sea fishing, just had 3-4 in an 80 litre evacool, would then tip a few litres of sea water in once we were out , the fish would come home at the end of the day nearly frozen.Just wash the bottles of and return to freezer, they worked great. Some lessons I learned , if you are going to use maxium saturation salt solution then you need a good freezer to get them solid,we had a large chest freezer and I would have to put them down the bottom up against the wall of the freezer, as for the hot water method, I used to get salt from the butcher, it was called flossy salt from memory it desolves quite easly in just cold tap water, you'll notice the difference in temperature of the water as you add the salt. Also discovered one day after washing the brinies I let them stand to drain off , at this time they were just liquid the fresh water on the outside froze. Just thought I would pass on my experience.
Cheers & good luck
Guy

its not worth the effort

Most domestic freezers only go down to -15 deg don't they. If you use too strong a brine, won't you have trouble freezing it ?

Mike

Just my two bobs worth, I bought a downunder fiberglass esky and froze two wine bladders,one with water and one with salty water(about 10%) and filled with beer and four 1litre frozen water bottles. The bladders were laid down on the bottom of the esky side by side and after two days the water bladder was still frozen solid and the salty one was completely melted,so now I just freeze water and they seem to last approx 4+ days before melting

So , what is the ACTUAL benefit , not a theoretical benefit ?

Does Salty Ice take days/week/months longer to thaw out , or is it a few hours ?

IMO , I like being able to use the cold water for other purposes , rather then just chucking it away.

This also sounds like a good way to extend the life of your water ice (the way some people use dry ice)

Cheers

I just noticed that one of my "Esky all purpose refreeze ice pack"s had sprung a leak and yep....salty water. Judging from the taste id say about 50% ......yuk.

rs

Ok Let's get practical.

Years ago my brother bought me one of those 4 bottle wine cooler/esky things. You know the one it has plstic bottles that act as dividers inside that you fill with water and freeze to keep the chardy cold. A friend also had one.

He filled his bottles with salt water for the reason expressed above. I filled mine with Cottee's Fruit Punch Cordial. It may have been some other flavour but you get the idea.

At the end of the day my mates kids were drinking salt water and mine had a nice drop of Cottee's. We both had nice cold chardy for the entire day, but my kids love me.

Duncs

And for those that got lost in the tech details - KISS - the point of this post is to get your Tinnies colder for longer

MY SUMMARY ON THIS POST WOULD BE:-

Firstly thanks to all who chipped in, it has been very informative and interesting.

I have learned a few things, and tried a few things, regarding the salt issue.

Firstly from direct practical test I found that it is indeed true that a 20% salt solution will take a long time and very low temps to freeze. (feel good nudie? you were to an extent correct! LOL)

Also it was noted a couple of posters found salt water inside reuseable freezer blocks... interesting

Freezer blocks dont take forever to freeze (you know the blue ones)

It would also appear that the only real advantage apart from a minor time extension, is a colder esky, which may not be all that great.

The above said, I would conclude that it COULD be advantageous to use a SMALL concentration of salt, more like 5%, which is probably similair to what you get in the freezer bricks, that way you will get slightly better temps without needing an ice age to freeze it solid.

And one other point, I would never use it in free blocks, ie always in a sealed container for reuse.

THE END

Rgds

Ron

PS My next question is a long debated one, so dont want to start another thread but wondered can you do a poll on here? so you just state your pref A or B?

prhaps someone can tell me?

My question is to drain your esky water or not? I've heard all the sides, I'm just interested in numbers on each side rather than individual ideas?