Dry ice -- How do the stores keep it from evaporating?

[LT72884]

Ok, how do stores keep dry ice from sublimation(i think i spelled that correctly) or evaporating?

Are the coolers at my local walmart some sort of special type of mechanism?

thanks

 

[Bystander]

They don't.

 

[LT72884]

They don't.

How do they keep it longer than i can at my house? a 5lb block is gone with in 30 hours, but yet, at the store, a 5 pound block has been in there for a while.

 

[Bystander]

The store runs its refrigerators at a lower temperature.

 

[LT72884]

The store runs its refrigerators at a lower temperature.

so your saying the cooler that they store the dry ice in is a powered refrigerator, like a meat freezer? thus keeping it longer? So if i put in a deep freezer, with no other food, would that be ok then?

 

[Tom.G]

The coolers I've seen locally (Southern californias) in the retails stores are just very heavily insulated boxes, no power or refrigeration used at all.

The plants that make the dry ice are a whole nother story! (they must have one heck of an electric bill!)

 

[Bystander]

https://en.wikipedia.org/wiki/Carbon_dioxide

 

[Klystron]

Leading to this.

Dry ice sublimates at 194.65 K (−78.5 °C; −109.3 °F), at Earth atmospheric pressures. This extreme cold makes the solid dangerous to handle without protection due to burns caused by freezing (frostbite). While generally not very toxic, the outgassing from it can cause hypercapnia (abnormally elevated carbon dioxide levels in the blood) due to buildup in confined locations.

 

[LT72884]

https://en.wikipedia.org/wiki/Carbon_dioxide

Thats a good read. I have red it in the past. I was just curious how my walmart stores it and what type of machine they use. Next time I am there, ill take a peek at it

 

[256bits]

so your saying the cooler that they store the dry ice in is a powered refrigerator, like a meat freezer? thus keeping it longer? So if i put in a deep freezer, with no other food, would that be ok then?

It will keep your freezer nice and cold.
The freezer will just act as an insulated storage box, with the motor not coming on until just about all the dry ice has sublimated. That depends of course on how big a chunk you put in there. A certain amount of dry ice has to sublimate to counter the heat flow into the freezer.

 

[256bits]

Leading to this.

Well, you can handle it as the dry ice does not conduct heat very well. Just don't put it down someone's back as a stupid joke, or squeeze a chunk in your fist.

 

[256bits]

Thats a good read. I have red it in the past. I was just curious how my walmart stores it and what type of machine they use. Next time I am there, ill take a peek at it

I didn't know Walmart or any other retailer had dry ice for sale to the public. We usually has to buy the bags from the "dry ice company". My guess is that they buy it in bulk every week and just store it some out of the place area.